Deformation directional lighting device

Abstract

A deformable directional lighting device may provide a near-eye display device or a vehicle exterior light device. The morphing near-eye display device includes a spatial light modulator having asymmetric pixels; inputting a transverse deformation lens; and an extraction waveguide that passes input light in a first direction between the polarization sensitive reflector and the front guide surface to the lateral deformation reflector and reflects light back through the extraction waveguide to guide between the rear guide surface and the front guide surface. The reflection extraction feature is arranged to extract the reflected light toward the viewer's pupil, thereby maintaining the directionality of the sector of the light from the spatial light modulator and the morphing imaging system. Thin, transparent and efficient morphing display devices for augmented reality and virtual reality displays as well as for scene illumination are provided.

Description

Technical Field

[0001] The present disclosure generally relates to near-eye display devices and illumination systems for near-eye display devices. Background Art

[0002] Head-mounted displays incorporating near-eye display devices can be arranged to provide fully immersive imagery (as in virtual reality (VR) displays) or augmented imagery superimposed on a view of the real world (as in augmented reality (AR) displays). If the superimposed imagery is aligned or superimposed with the real world, it can be referred to as mixed reality (MR). In VR displays, the near-eye display device is typically opaque to the real world, while in AR displays, the optical system is partially transmissive to light from the real world.

[0003] Near-eye display devices for AR and VR displays are intended to provide images to at least one eye of a user in full color, high resolution, high brightness, and high contrast, and with a wide field of view (angular size of the image) and large eyebox size (geometry over which the eye can move while having visibility of the entire image field of view). Such displays are desirable in a slim form factor, light weight, and for low manufacturing cost and complexity.

[0004] Further, AR near-eye display devices are intended to have high transmission of real-world light without image distortion or degradation, and reduced glare from stray light away from the wearer of the display. AR optics can be roughly classified as either reflective combiner type or waveguide type. The waveguide type typically achieves reduced form factor and weight due to the folding of the light path within the waveguide. Known methods for injecting images into waveguides can use a spatial light modulator and a projection lens arrangement with a prism or grating to couple light into the waveguide. The pixel sites in the spatial light modulator are converted into a fan of light directions by the projection lens. In other arrangements, a laser scanner can provide a fan of light directions. The angular position is propagated through the waveguide and output to the user's eye. The optical system of the eye collects the angular position and provides a spatial image at the retina. Summary of the invention

[0005] According to a first aspect of the present disclosure, a deformable near-eye display device is provided, the deformable near-eye display device comprising: an illumination system, the illumination system comprising a spatial light modulator, the illumination system being arranged to output light; and an optical system, the optical system being arranged to guide the light from the illumination system to the eyes of a viewer, wherein the optical system has an optical axis and has a deformable property in a lateral direction and a transverse direction perpendicular to each other and perpendicular to the optical axis, wherein the spatial light modulator comprises pixels distributed in the lateral direction, and the optical system comprises: a transverse deformable component, the transverse deformable component having a positive optical power in the transverse direction, wherein the transverse deformable component is arranged to receive light from the spatial light modulator, and the illumination system is arranged so that the light from the transverse deformable component is output to the eyes of a viewer. The light output by the component is guided to a direction distributed in a lateral direction; an extraction waveguide, the extraction waveguide is arranged to receive light from the lateral deformation component; a lateral deformation component, the lateral deformation component has a positive optical power in the lateral direction, the extraction waveguide is arranged to guide the light from the lateral deformation component along the extraction waveguide to the lateral deformation component in a first direction; and a light reverse reflector, the light reverse reflector is arranged to reflect the light guided along the extraction waveguide in the first direction to form light guided along the extraction waveguide in a second direction opposite to the first direction, wherein: the extraction waveguide includes: a front guiding surface; a polarization-sensitive reflector, the polarization-sensitive reflector is opposite to the front guiding surface; and an extraction element, the extraction element is arranged at the polarization-sensitive The optical system further comprises a polarization conversion retarder disposed between the polarization-sensitive reflector and the light reverse reflector, wherein the polarization conversion retarder is arranged to convert the polarization state of light passing through the polarization conversion retarder between a linear polarization state and a circular polarization state, and the polarization conversion retarder and the light reverse reflector are arranged in combination to rotate the input linear polarization state of the light guided in the first direction, so that light guided in the second direction and output from the polarization conversion retarder has an orthogonal linear polarization state orthogonal to the input linear polarization state; the polarization-sensitive reflector is arranged to reflect light with the input linear polarization state guided in the first direction and transmit light with the orthogonal linear polarization state guided in the second direction, so that the front guiding surface and the polarization-sensitive reflector are arranged to guide light in the first direction, and the front guiding surface and the rear guiding surface are arranged to guide light in the second direction; and the array of extraction features is arranged to extract light guided along the extraction waveguide in the second direction through the front guiding surface toward the viewer's eyes, and the array of extraction features is distributed along the extraction waveguide to provide exit pupil expansion in the lateral direction.

[0006] The deformable near-eye display device can provide an image with a wide field of view with high brightness and high efficiency. The compact physical orientation and low weight of the deformable near-eye display device can be implemented to provide high comfort of use and extend viewing time. High transparency can be provided. Images can be provided with reduced color blur. Large-sized eye boxes can be implemented to relax the restrictions of pupil positioning at the desired visual relief distance, and vignetting-free images can be achieved over a wide range of observer pupil positions and for a wide field of view. The deformable near-eye display device can be suitable for augmented reality applications and virtual reality applications.

[0007] The polarization sensitive reflector may include a reflective linear polarizer. High efficiency may be advantageously achieved. The reflective linear polarizer may be provided with low thickness and high flatness to advantageously achieve high resolution output. The reflective linear polarizer may be conveniently manufactured at low cost on the region of the extraction waveguide. Light propagating along the second direction may be efficiently transmitted to the extraction feature. High efficiency and uniformity may be achieved. The exit pupil size may be increased. High image brightness uniformity over a wide field of view may be achieved.

[0008] The polarization conversion retarder may have a quarter wavelength retardation at a visible light wavelength (e.g., 550 nm). High polarization conversion efficiency for light propagating along the extraction waveguide in the second direction may be achieved. Advantageously, high efficiency image contrast and image uniformity may be improved.

[0009] The input linear polarization state may be a p-polarization state in an extraction waveguide, or the input linear polarization state may be an s-polarization state in an extraction waveguide. The optical system may further include an input linear polarizer, which may be disposed between the spatial light modulator and the polarization-sensitive reflector and arranged to pass light having the input linear polarization state. Light propagating along the extraction waveguide in the first direction and the second direction may experience reduced oblique ray depolarization. Advantageously, uniformity and efficiency may be improved.

[0010] An input linear polarizer may be arranged between the spatial light modulator and the extraction waveguide.Manufacturing costs may advantageously be reduced.

[0011] An input linear polarizer may be disposed within the extraction waveguide. Advantageously, depolarization along the extraction waveguide may be reduced and efficiency may advantageously be improved.

[0012] The input linear polarizer may be arranged behind the lateral anamorphic assembly, and the optical system may further include a polarization conversion retarder arranged between the lateral anamorphic assembly and the input linear polarizer, the polarization conversion retarder being arranged to convert the polarization state of light passing through the polarization conversion retarder between a linear polarization state and a circular polarization state. The illumination system may be arranged to output light which may be unpolarized, or the illumination system may be arranged to output light having the input linear polarization state. Stray light from back reflections falling on the input end may be reduced. Advantageously, image contrast may be improved.

[0013] The extraction features may be elongated in the lateral direction. The lateral size of the exit pupil may be increased. Advantageously, viewer comfort may be improved.

[0014] The rear guiding surface may include extraction facets, which may be extraction features, each of which is arranged to reflect light directed in the second direction through the front guiding surface toward the eye of the viewer. Light propagating in the second direction may be output from the extraction waveguide. After imaging through the lateral deformation component and the side deformation component, the image may be provided on the retina of the user. Advantageously, a wide field of view and a high resolution image with high brightness may be achieved.

[0015] The rear guiding surface comprises a plurality of outwardly protruding prisms, each of the prisms comprising at least one extraction facet and at least one draft facet. The prisms can advantageously be provided by a low cost and low complexity tooling and replication process with high surface reproducibility and accuracy.

[0016] At least one of the prisms may comprise a plurality of draft facets, and an intermediate guiding facet disposed between each adjacent pair of the plurality of draft facets.Advantageously, spatial uniformity across the exit pupil may be improved.

[0017] The prisms may each further include a primary guiding facet between the at least one extraction facet and the at least one draft facet.A metal-free coating may be provided on the prisms, advantageously reducing cost and complexity, and improving transmission efficiency.

[0018] The rear guiding surface may include guiding portions between the prisms. Transmission efficiency may be improved. Output uniformity in the lateral direction across the exit pupil may be improved, and image vignetting may be reduced.

[0019] The rear directing surface may comprise a surface relief grating comprising said extraction features.Advantageously, the aperture size of the optical element is increased and diffraction from the aperture is reduced.

[0020] The extraction element may comprise an array of extraction reflectors arranged inside the extraction waveguide.Advantageously, improved efficiency may be achieved and tolerance to surface damage may be improved.

[0021] The array of extraction reflectors may be arranged between the polarization-sensitive reflector and the rear light guiding surface. Advantageously, improved efficiency may be achieved and tolerance to surface damage may be improved.

[0022] The array of reflectors may have a reflectivity defined across their entire area that increases with increasing distance along the optical axis.Advantageously, the uniformity of the output image for varying eye locations within the exit pupil may be improved.

[0023] The extraction reflector may include extraction surfaces separated by a partially reflective coating. Advantageously, an image may be provided without missing corner regions. Efficiency, brightness and contrast may be improved, and the visibility of artifacts (including ghosting and ghost images) caused by stray light may be reduced.

[0024] The partially reflective coating may comprise at least one dielectric layer. Advantageously, manufacturing costs may be reduced.

[0025] The at least one dielectric layer may comprise a stack of dielectric layers. Advantageously, brightness and uniformity may be improved.

[0026] The partially reflective coating may be metallic.Advantageously, manufacturing costs may be reduced.

[0027] The extraction reflector may extend partially across the extraction waveguide, between the opposite rear and front guiding surfaces of the extraction waveguide, in a continuously shifted position. Advantageously, the manufacturing cost of the extraction waveguide may be reduced. High uniformity with viewing angles may be achieved for pupil locations across a moving headbox.

[0028] The anamorphic near-eye display device may further include an intermediate reflector extending along the extraction waveguide between adjacent pairs of extraction reflectors. Advantageously, manufacturing costs may be reduced.

[0029] The partially reflective coating may comprise at least one dielectric layer. Advantageously, manufacturing costs may be reduced.

[0030] The at least one dielectric layer may comprise a stack of dielectric layers. Advantageously, brightness, efficiency and uniformity may be improved.

[0031] The polarization-sensitive reflector may include a nematic liquid crystal layer. The liquid crystal layer may include a liquid crystal material disposed between opposing first and second orientation layers. A component of an optical axis of the liquid crystal layer in the plane of the liquid crystal layer may be parallel or orthogonal to a first direction along the extraction waveguide. Advantageously, a low thickness reflector may be provided with low scattering and high transparency.

[0032] The polarization-sensitive reflector may include a cholesteric liquid crystal layer. The deformable near-eye display device may further include a polarization conversion retarder arranged between the front guiding surface and the cholesteric liquid crystal retarder, wherein the polarization conversion retarder may be arranged to convert the polarization state of light passing through the polarization conversion retarder between a linear polarization state and a circular polarization state, and the polarization conversion retarder and the cholesteric liquid crystal layer may be arranged in combination to reflect the input linear polarization state of light guided in a first direction and transmit the linear polarization state of light guided in a second direction. The deformable near-eye display device may further include a polarization conversion retarder arranged between the rear guiding surface and the cholesteric liquid crystal retarder, wherein the polarization conversion retarder may be arranged to convert the polarization state of light passing through the polarization conversion retarder between a linear polarization state and a circular polarization state. Advantageously, high reflectivity can be achieved over a wide field of view for light having a linear polarization state propagating in the first direction, and high transmittance can be achieved for light propagating in the second direction. The cholesteric liquid crystal layer may have a low thickness.

[0033] The extraction waveguide may have an input end extending in a lateral direction and a transverse direction, the extraction waveguide being arranged to receive light from the illumination system through the input end. The direction of the optical axis through the transverse deformation component may be tilted relative to a first direction and a second direction along the extraction waveguide. The input end may be tilted relative to the first direction and the second direction along the extraction waveguide. An input linear polarizer may be disposed between the spatial light modulator and the input end of the extraction waveguide. The polarization conversion retarder may have a quarter wavelength delay at a visible light wavelength. Light may be input into the extraction waveguide at an angle where it can be extracted without ghosting. Image contrast may advantageously be improved.

[0034] The light retro-reflector may be a reflective end of an extraction waveguide. The laterally deformable assembly may include a light retro-reflector. Advantageously, manufacturing costs and complexity may be reduced. Interface losses may be reduced.

[0035] The lateral anamorphic assembly may include a lens. The lens of the lateral anamorphic assembly may be a composite lens. Advantageously, aberrations in the lateral direction may be reduced.

[0036] The optical system may include an input section including an input reflector, which is a laterally deformable component and may be arranged to reflect light from the illumination system and guide the light along an extraction waveguide. Advantageously, manufacturing complexity, cost may be reduced, and weight may be reduced.

[0037] The lateral anamorphic assembly may further include a lens. Advantageously, aberrations may be reduced, image fidelity may be improved, and the size of the dynamic head frame may be increased.

[0038] The input section may further include an input face, the input face being disposed on the front side or the rear side of the waveguide and facing the input reflector, and the input section may be arranged to receive light from the illumination system through the input face. In the case where the input face is on the front side of the waveguide, the input face may extend to the front guide surface at an acute angle, or in the case where the input face is on the rear side of the waveguide, the input face may extend to the rear guide surface at an acute angle. In the case where the input face is on the front side of the waveguide, the input face may extend parallel to the front guide surface, or in the case where the input face is on the rear side of the waveguide, the input face may extend parallel to the rear guide surface. In the case where the input face is on the front side of the waveguide, the input face may be coplanar with the front guide surface, or in the case where the input face is on the rear side of the waveguide, the input face may be coplanar with the rear guide surface. The input face may be disposed outside one of the front guide surface or the rear guide surface. The input section may further include a separation face, the separation face extending outwardly from one of the front guide surface or the rear guide surface to the input face. Advantageously, an improved mechanical arrangement of the illumination system and the optical system may be achieved.

[0039] The input section may be integral with the waveguide.Advantageously, manufacturing complexity may be reduced and lower costs may be achieved.

[0040] The waveguide may have an end which is an input face, the waveguide being arranged to receive light from the illumination system through the input face, and the input section may be a separate element from the waveguide, the separate element may further comprise an output face and be arranged to guide light reflected by the input reflector through the output face and into the waveguide through the input face of the waveguide. Advantageously, improved aberrations may be achieved. The reflective surface may be protected.

[0041] The pixels of the spatial light modulator may also be distributed in a lateral direction so that light output from the lateral anamorphic component may be directed in a direction that may be distributed in a lateral direction. Advantageously, image rows may be provided simultaneously. Image splitting artifacts may be reduced.

[0042] The lighting system may further comprise a deflector element arranged to deflect light output from the lateral deformation assembly by a selectable amount, the deflector element being selectively operable to direct light output from the lateral deformation assembly into a direction that may be distributed in a lateral direction. Advantageously, the complexity of the lighting system may be reduced.

[0043] The spatial light modulator may include pixels having a pitch in the lateral direction and the transverse direction, and the ratio of the pitch may be the same as the inverse of the ratio of the optical powers of the lateral anamorphic optical element and the transverse anamorphic optical element. Advantageously, an observer may perceive square pixels. Image fidelity may be improved.

[0044] The anamorphic near-eye display device may further comprise a control system arranged to operate the illumination system to provide light input in accordance with image data representing the image. Advantageously, the image data may be perceived to provide an augmented reality image or a virtual reality image.

[0045] According to a second aspect of the present disclosure, a head mounted display device is provided, the head mounted display device comprising the deformable near eye display device according to the first aspect, arranged to fix the deformable near eye display device on the head of a wearer, wherein the deformable near eye display device extends across at least one eye of the wearer. Virtual reality images and augmented reality images can be conveniently provided to a moving observer.

[0046] The head mounted display device may further include a lens having optical power, the anamorphic near eye display device overlying one or each lens. The nominal viewing distance of the virtual image may be adjusted to achieve a reduced difference between focusing and converging depth cues in the stereoscopic display device. Correction for the visual characteristics of the viewer's eyes may be provided.

[0047] The head mounted display device may include a pair of glasses. Advantageously, a light weight transparent head mounted display device suitable for augmented reality applications may be achieved.

[0048] According to a third aspect of the present disclosure, a deformable directional lighting device is provided, the deformable directional lighting device comprising: a lighting system, the lighting system comprising a light source array, the lighting system being arranged to output light; and an optical system, the optical system being arranged to guide the light from the lighting system, wherein the optical system has an optical axis, and has a deformable property in a lateral direction and a transverse direction perpendicular to each other and perpendicular to the optical axis, wherein the light source array comprises light sources distributed in the lateral direction, and the optical system comprises: a transverse deformable component, the transverse deformable component having a positive optical power in the transverse direction, wherein the transverse deformable component is arranged to receive light from the light source array, and the lighting system is arranged so that the light from the transverse deformable component The output light is guided to a direction distributed in the lateral direction; an extraction waveguide, the extraction waveguide is arranged to receive light from the lateral deformation component; a lateral deformation component, the lateral deformation component has a positive optical focal length in the lateral direction, the extraction waveguide is arranged to guide the light from the lateral deformation component along the extraction waveguide to the lateral deformation component in a first direction; and a light reverse reflector, the light reverse reflector is arranged to reflect the light guided along the extraction waveguide in the first direction to form light guided along the extraction waveguide in a second direction opposite to the first direction, wherein: the extraction waveguide includes: a front guiding surface; a polarization-sensitive reflector, the polarization-sensitive reflector is opposite to the front guiding surface; and an extraction element, The extraction element is arranged outside the polarization-sensitive reflector, and the extraction element includes: a rear guiding surface, the rear guiding surface is opposite to the front guiding surface; and at least one extraction feature; the deformed directional lighting device is arranged to provide an input linear polarization state for the light guided along the extraction waveguide in the first direction before the light guided along the extraction waveguide in the first direction reaches the polarization-sensitive reflector; and the optical system further includes a polarization conversion retarder arranged between the polarization-sensitive reflector and the light reverse reflector, wherein the polarization conversion retarder is arranged to convert the polarization state of the light passing through the polarization conversion retarder between a linear polarization state and a circular polarization state, and the polarization conversion retarder and the light reverse reflector are arranged in combination The invention relates to a method for producing an optical waveguide having an optical waveguide having an optical waveguide structure and a plurality of optical waveguides, wherein the optical waveguide structure comprises a plurality of optical waveguides, wherein the plurality of optical waveguides are arranged to rotate an input linear polarization state of light guided in a first direction so that light guided in a second direction and output from the polarization conversion retarder has an orthogonal linear polarization state orthogonal to the input linear polarization state; a polarization-sensitive reflector is arranged to reflect light guided in the first direction having the input linear polarization state and transmit light guided in the second direction having the orthogonal linear polarization state, so that the front guiding surface and the polarization-sensitive reflector are arranged to guide light in the first direction, and the front guiding surface and the rear guiding surface are arranged to guide light in the second direction; and at least one extraction feature is arranged to extract light guided in the second direction along the extraction waveguide through the front guiding surface. Additional illumination devices can be provided in a compact arrangement at low cost. A high-resolution output beam that can be controllable and has high efficiency can be provided.

[0049] According to a fourth aspect of the present disclosure, there is provided a vehicle exterior lamp device, comprising: a deformed directional lighting device according to the third aspect. The height of the emission aperture can be reduced to advantageously achieve a desired aesthetic appearance. High illumination of the illuminated scene can be achieved by high resolution imaging of addressable light cones in one or two dimensions. High image contrast can be achieved for adjustable beam shaping. Image glare for an oncoming viewer of the lighting device can be reduced, while improved visibility of the scene surrounding the oncoming viewer can be achieved.

[0050] Any of the various aspects of the present disclosure may be applied in any combination.

[0051] Embodiments of the present disclosure can be used in various optical systems. Embodiments can include various projectors, projection systems, optical components, displays, microdisplays, computer systems, processors, self-contained projector systems, vision and / or audio-visual systems, and electrical devices and / or optical devices, or work together with various projectors, projection systems, optical components, displays, microdisplays, computer systems, processors, self-contained projector systems, vision and / or audio-visual systems, and electrical devices and / or optical devices. Aspects of the present disclosure can be used together with almost any equipment related to optical devices and electrical devices, optical systems, demonstration systems, or any equipment that can include any type of optical system. Therefore, embodiments of the present disclosure can be used in optical systems, devices used in visual presentation and / or optical presentation, visual peripherals, etc., and in several computing environments and automotive environments.

[0052] Before continuing to discuss the disclosed embodiments in detail, it should be understood that the present disclosure is not limited to the details of the specific arrangements shown in its application or creation, as the present disclosure is capable of other embodiments. Moreover, various aspects of the present disclosure may be set forth in different combinations and arrangements to define their own unique embodiments. In addition, the terms used herein are for the purpose of description rather than limitation.

[0053] These and other advantages and features of the present disclosure will become apparent to those of ordinary skill in the art after reading this disclosure in its entirety. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The embodiments are illustrated by way of example in the accompanying drawings, in which like reference numerals indicate similar parts, and in which:

[0055] Figure 1A is a schematic diagram illustrating a front perspective view of a morphing near-eye display device;

[0056] Figure 1B is a graphic illustration used for Figure 1AA schematic diagram of a front perspective view of a coordinate system arrangement of a deformed near-eye display device;

[0057] Figure 1C is a schematic diagram illustrating, in side view, the operation of a near-eye display in a transverse plane;

[0058] Figure 1D is a schematic diagram illustrating, in side view, operation of a near-eye display in a lateral plane orthogonal to the transverse plane;

[0059] Figure 1E is a graphic illustration used for Figure 1A A schematic diagram of a front perspective view of a coordinate system mapping of a deformable near-eye display device;

[0060] Figure 1F It is a graphic illustration Figure 1A A schematic diagram of a field of view plot of an output of a deformable near-eye display device for multi-color illumination;

[0061] Figure 2A , Figure 2B and Figure 2C is illustrated in front view for Figure 1A Schematic diagram of an arrangement of a spatial light modulator including spatially multiplexed red, green and blue sub-pixels used in a deformed near-eye display device;

[0062] Figure 2D is illustrated in front view for Figure 1A Schematic diagram of a spatial light modulator for use with time-multiplexed spectral illumination used in a deformable near-eye display device;

[0063] Figure 3A is a schematic diagram illustrating a side view of light input into an extraction waveguide;

[0064] Figure 3B is a schematic diagram illustrating a side view of light propagation along a first direction in an extraction waveguide;

[0065] Figure 3C The illustration is from Figure 1A A schematic diagram of a side view of light extraction of a deformed near-eye display device;

[0066] Figure 4A is a schematic diagram illustrating a side view of light output from a morphing near-eye display device for a single extraction feature;

[0067] Figure 4B is a schematic diagram illustrating a side view of light output from an anamorphic near-eye display device for a plurality of extraction features to achieve a full cone of light input into a pupil of a viewer in a lateral direction;

[0068] Figure 4C is a schematic diagram illustrating a side view of light output from an anamorphic near-eye display device for multiple locations for a viewer moving in a lateral direction;

[0069] Figure 5A It is a diagram illustrating Figure 1A A schematic diagram of a front view of light output by a deformed near-eye display device;

[0070] Figure 5B This is a diagram illustrating the position of a single pupil. Figure 1A A schematic diagram of a front view of a deformed near-eye display device;

[0071] Figure 5C is a diagram illustrating the position of the pupil for multiple Figure 1A A schematic diagram of a front view of a deformed near-eye display device;

[0072] Figure 5D is a schematic diagram illustrating a front view of an extraction waveguide and an exit pupil;

[0073] Figure 5E is a schematic diagram illustrating a side view of an expanded imaging system arranged for imaging in a lateral direction, wherein a reflection extraction feature is not provided;

[0074] Fig. 5F is a schematic diagram illustrating a top view of a deployed imaging system arranged to image in a lateral direction;

[0075] Figure 5G is a schematic diagram illustrating a side view of an expanded imaging system arranged for imaging in a lateral direction, wherein the array of extraction features is provided as reflective extraction features;

[0076] Fig. 6A It is a graphic illustration Figure 1A A schematic diagram of a side view of polarized light propagation in a deformed near-eye display device;

[0077] Figure 6B It is a graphic illustration Fig. 6A Schematic diagram of a front view of polarized light propagation in a deformed near-eye display device;

[0078] Figure 6C It is illustrated by FIG. 6A to FIG. 6B Schematic diagram of the alignment direction of the polarization control component;

[0079] Fig.6D is a schematic diagram illustrating a side view of polarized light propagation in a deformable near-eye display device, wherein the polarization state propagating along a first direction is orthogonal to Fig. 6A Arrangement;

[0080] Fig. 6EIt is a graphic illustration Fig.6D Schematic diagram of a front view of polarized light propagation in a deformed near-eye display device;

[0081] Fig. 6F It is illustrated by FIG. 6D to FIG. 6E Schematic diagram of the alignment direction of the polarization control component;

[0082] Fig. 7A is a schematic diagram illustrating a side view of the operation of an alternative polarization-sensitive reflector including a thin film stack;

[0083] Figure 7B is a schematic graph illustrating the variation of thin film stack transmission versus wavelength for incident s-polarized light and p-polarized light;

[0084] Figure 7C is a flow chart illustrating pixel-level compensation for correction of transmission of a thin film stack polarization-sensitive reflector;

[0085] Fig. 8A is a schematic diagram illustrating a front view of a deformed near-eye display device including an alternative polarization-sensitive reflector including an in-plane liquid crystal layer;

[0086] Figure 8B is illustrated in top view Fig. 8A Schematic diagram of a liquid crystal layer of a polarization-sensitive reflector;

[0087] Figure 8C is illustrated in side view Fig. 8A Schematic diagram of a liquid crystal layer of a polarization-sensitive reflector;

[0088] Fig. 9A is a schematic diagram illustrating a side view of the operation of an alternative polarization-sensitive reflector including an in-plane liquid crystal layer for p-polarized light propagating along an extraction waveguide in a first direction;

[0089] Fig. 9B is a schematic diagram illustrating a side view of the operation of an alternative polarization-sensitive reflector of 9A for light propagating along an extraction waveguide in a second direction;

[0090] Fig. 10A is a schematic diagram illustrating a side view of the operation of an alternative polarization-sensitive reflector including a cholesteric liquid crystal layer for light propagating along an extraction waveguide in a first direction;

[0091] Fig. 10B It is a graphic illustration Fig. 10A A schematic diagram of a side view of an alternative polarization-sensitive reflector for operation of light propagating along an extraction waveguide in a second direction;

[0092] Fig.11A , Fig. 11B and Fig. 11C is a schematic diagram illustrating side views of various arrangements of polarization-sensitive reflectors;

[0093] Fig. 12A is a schematic diagram illustrating a side view of the operation of an array of extraction features, the extraction features each comprising a prism, the prisms comprising an extraction facet, a guiding facet, and a draft facet, wherein a pitch of the prisms varies along an extraction waveguide;

[0094] Fig. 12B is a schematic diagram illustrating a side view of the operation of an array of extraction features, the extraction features each comprising a prism including an extraction facet and a draft facet;

[0095] Fig. 12C is a schematic diagram illustrating a side view of the operation of an array of extraction features, each of which includes an extraction facet and a draft facet;

[0096] Fig.12D is a schematic diagram illustrating a side view of the operation of an alternative array of extraction features, each of which includes an extraction facet and a draft facet;

[0097] Fig.12E is a schematic diagram illustrating a side view of the operation of an array of extraction features, the extraction features including extraction features of different shapes;

[0098] Fig.12F is a schematic diagram illustrating a side view of the operation of an array of extraction features, the extraction features including a rear guide surface including a stepped extraction feature;

[0099] Fig.13A is a schematic diagram illustrating a side view of light output from an extraction waveguide including an array of extraction features having a draft facet arranged for each extraction facet;

[0100] Fig. 13B is a schematic diagram illustrating a side view of light output from an extraction waveguide including an array of extraction features having intermediate draft facets and intermediate guiding facets arranged for each extraction facet;

[0101] Fig. 13C is a schematic diagram illustrating a side view of an extraction waveguide including an array of extraction features having intermediate draft facets and intermediate guiding facets arranged for one of the extraction facets;

[0102] Fig.14A is a schematic diagram illustrating a side view of the operation of a stepped reflective layer including an array of extraction features;

[0103] Fig. 14B is a schematic graph illustrating the variation of reflectivity versus wavelength for light propagating through an extraction reflector including the dielectric layers listed in Table 4;

[0104] Fig.15 is a schematic diagram illustrating a side view of operation wherein an array of extraction features includes an inclined partially reflective surface;

[0105] Fig.16 is a diagram illustrating the reflectivity of a partially reflecting surface along Fig.15 Schematic diagram of the changes of the extraction waveguide;

[0106] Fig.17A is a schematic diagram illustrating, in a perspective front view, an alternative arrangement of a anamorphic near-eye display device in which some of the polarizing beam splitters do not extend the entire thickness of the extraction waveguide;

[0107] Fig. 17B is illustrated in side view Fig.17A A schematic diagram of the operation of a deformed near-eye display device;

[0108] Fig.18A is a schematic diagram illustrating, in a perspective front view, an alternative arrangement of an anamorphic near-eye display device in which a polarizing beam splitter is patterned;

[0109] Fig.18B is illustrated in side view Fig.18A A schematic diagram of the operation of a deformed near-eye display device;

[0110] Fig.19A is a schematic diagram illustrating, in side view, an arrangement of an extraction waveguide including an alternative array of extraction features;

[0111] Fig.19B is a schematic graph illustrating the variation of reflectivity with incident angle for polarized light from a dichroic stack;

[0112] Fig.19C is a schematic diagram illustrating, in side view, an arrangement of an extraction waveguide including an alternative array of extraction features;

[0113] Fig.19D is a schematic diagram illustrating, in side view, an arrangement of an extraction waveguide including an alternative array of extraction features;

[0114] Fig. 20A is a schematic diagram illustrating a side view of the operation of an array of extraction features including a surface relief grating;

[0115] Fig. 20Bis a schematic diagram illustrating a side view of the operation of an array of extraction features including a volume diffractive optical element;

[0116] Fig. 20C is a schematic diagram illustrating a side view of the operation of an array of extraction features including different types of extraction features;

[0117] Fig.21A is a schematic diagram illustrating a side view of optical isolation for a morphed near-eye display device including an emissive spatial light modulator;

[0118] Fig.21B It is illustrated by Fig.21A Schematic diagram of the optical axis alignment direction of the polarization control component;

[0119] Fig. 21C is a schematic diagram illustrating a side view of optical isolation for a morphed near-eye display device including a transmissive or reflective spatial light modulator;

[0120] Fig.21D It is illustrated by Fig. 21C Schematic diagram of the optical axis alignment direction of the polarization control component;

[0121] Fig.22A is a schematic graph of stepped surface height as a function of position along an extraction waveguide for various illustrative arrangements of steps for the stepped surface;

[0122] Fig. 22B is a schematic graph of facet width as a function of position along an extraction waveguide for various illustrative arrangements of steps for a stepped surface;

[0123] Fig. 22C is a schematic diagram illustrating, in front view, an arrangement of chirp extraction features for a monocular near-eye anamorphic display device;

[0124] Fig.22D is a schematic diagram illustrating, in front view, an arrangement of chirp extraction features for a binocular near-eye anamorphic display device;

[0125] Fig.23A is a schematic diagram illustrating an augmented reality head mounted display device in a perspective front view, the augmented reality head mounted display device including a right eye anamorphic display device having a spatial light modulator arranged at an eyebrow position;

[0126] Fig. 23B is a schematic diagram illustrating an augmented reality head mounted display device in a perspective front view, the augmented reality head mounted display device including a left eye anamorphic display device and a right eye anamorphic display device having spatial light modulators arranged at eyebrow locations;

[0127] Fig.23C is a schematic diagram illustrating, in a perspective front view, an eyepiece arrangement for an augmented reality head mounted display device;

[0128] Fig.24A is a schematic diagram illustrating, in a perspective front view, a deformable near-eye display device having a spatial light modulator at the temple location;

[0129] Fig. 24B is a schematic diagram illustrating an augmented reality head mounted display device in a perspective front view, the augmented reality head mounted display device including a left eye anamorphic display device having a spatial light modulator disposed at a temple position;

[0130] Fig.24C is a schematic diagram illustrating an augmented reality head mounted display device in a perspective front view, the augmented reality head mounted display device including a left eye anamorphic display device and a right eye anamorphic display device having spatial light modulators arranged at temple positions;

[0131] Fig.25A is a schematic diagram illustrating, in front view, a virtual reality head mounted display device including a left eye anamorphic display device and a right eye anamorphic display device;

[0132] Fig.25B is a schematic diagram illustrating, in side view, a virtual reality head mounted display device including a morphing near eye display device;

[0133] Fig.25C is a schematic diagram illustrating, in front view, a morphed near-eye display device including a single waveguide adapted for use with both eyes of a display user;

[0134] Fig.25D is a schematic diagram illustrating, in side view, a head mounted display device including two deformed near-eye display devices;

[0135] Fig.25E is a schematic diagram illustrating a composite image;

[0136] Fig.26A is a schematic diagram illustrating, in side view, a virtual reality head mounted display device including a deformable near eye display device arranged to receive light from a magnifying lens and an attached spatial light modulator;

[0137] Fig.26B is a schematic diagram illustrating, in side view, a virtual reality head mounted display device including an anamorphic near eye display device disposed between an anamorphic spatial light modulator and a magnifying lens of a non-anamorphic near eye display device;

[0138] Fig.27Ais a schematic diagram illustrating, in side view, an arrangement of a virtual image distance for a virtual reality display device;

[0139] Fig.27B and Fig.27C This diagram is for Fig.27A a schematic diagram of an arrangement of displayed images;

[0140] Fig.28A is a schematic diagram illustrating in front view an anamorphic near-eye display device including a reflective end, the reflective end including a Pancharatnam-Berry lens;

[0141] Fig.28B is a schematic diagram illustrating the optical structure of a Pancharatnam-Berry lens in end view;

[0142] Fig.28C is illustrated in front view Fig.28B Schematic diagram of the optical structure of the Pancharatnam-Berry lens;

[0143] Fig.29 This diagram is for Fig.28B Schematic diagram of the variation of the phase difference of an illustrative Pancharatnam-Berry lens with lateral position;

[0144] Fig.30 is illustrated in side view Fig.28A Schematic diagram of the operation of the Pancharatnam-Berry lens;

[0145] Fig.31A is a schematic diagram illustrating, in side view, the operation of an anamorphic near-eye display device further including a corrective eyeglass lens;

[0146] Fig.31B is a schematic diagram illustrating, in side view, the operation of an anamorphic near-eye display device further comprising a corrective Pancharatnam-Berry lens and a corrective eyeglass lens;

[0147] Fig.32A is a schematic diagram illustrating, in side view, a head mounted display device including a first focal plane modifying lens and a second focal plane modifying lens;

[0148] Fig.32B is a schematic diagram illustrating, in side view, a head mounted display device, the head mounted display device including a plurality of extraction waveguides and further including a first focal plane modifying lens and a second focal plane modifying lens;

[0149] Fig.32C is a schematic diagram illustrating, in side view, a head mounted display device including a plurality of extraction waveguides and three focal plane modifying lenses;

[0150] Fig.32Dis a schematic diagram illustrating, in side view, a head mounted display device including a non-deformed near-eye display device and a deformed extraction waveguide;

[0151] Fig.32E is a schematic diagram illustrating, in side view, a head mounted display device including a non-anamorphic near eye display device, an anamorphic extraction waveguide, and a focal plane modifying lens disposed between the non-anamorphic near eye display device and the anamorphic near eye display device;

[0152] Fig.32F is a schematic diagram illustrating, in side view, a head mounted display device including a non-anamorphic near eye display device, an anamorphic extraction waveguide, and a focal plane modifying lens arranged to receive light from the non-anamorphic near eye display device and the anamorphic near eye display device;

[0153] Figure 32G is a schematic diagram illustrating, in side view, a head mounted display device including a non-deformed near-eye display device, a deformed extraction waveguide, and two focal plane modifying lenses;

[0154] Fig.32H is a schematic diagram illustrating, in side view, a head mounted display device including a non-deformed near-eye display device, two deformed extraction waveguides, and a focal plane modifying lens;

[0155] Fig.33A is a schematic diagram illustrating details of the arrangement of an input focusing lens in side view;

[0156] Fig.33B is illustrated in front view Fig.33A A schematic diagram of details of the arrangement of the input focusing lens;

[0157] Fig.34A is a schematic diagram illustrating, in side view, an arrangement of spatial light modulators for use in the anamorphic near-eye display device of FIG. 1 , the anamorphic near-eye display device including separate red, green and blue spatial light modulators and a beam combining element;

[0158] Fig.34B is a schematic diagram illustrating, in side view, an illumination system for use in the modified near-eye display device of FIG. 1 including a birdbath folding arrangement;

[0159] Fig.34C is a schematic diagram illustrating, in side view, a spatial light modulator arrangement for use in an anamorphic near-eye display device including a laterally anamorphic component, the laterally anamorphic component including a reflector;

[0160] Fig.35Ais a schematic diagram illustrating a front perspective view of a deformed near-eye display device including an input reflector;

[0161] Fig.35B It is a graphic illustration Fig.35A A schematic diagram of a side view of a deformed near-eye display device;

[0162] Fig.35C It is a graphic illustration Fig.35A A schematic diagram of a front view of a deformed near-eye display device;

[0163] Fig.35D is a schematic diagram illustrating a side view of an alternative deformable near-eye display device including an input reflector;

[0164] Fig.35E is a schematic diagram illustrating a side view of a deformed near-eye display device including an alternative input reflector;

[0165] Fig.35F is a schematic diagram illustrating a side view of a deformed near-eye display device including an alternative input reflector;

[0166] Figure 35G is a schematic diagram illustrating a side view of a deformed near-eye display device including an alternative input reflector;

[0167] Fig.36A is a schematic diagram illustrating an alternative arrangement of an input focusing lens in a perspective front view;

[0168] Fig.36B is a schematic diagram illustrating, in side view, a spatial light modulator arrangement for use in the anamorphic near-eye display device of FIG. 1 , the anamorphic near-eye display device including a spatial light modulator including a laser scanner and a light diffusing screen;

[0169] Fig.37A is a schematic diagram illustrating in side view an input of an extraction waveguide including a laser source and a scanning arrangement;

[0170] Fig.37B is a schematic diagram illustrating in front view a spatial light modulator arrangement comprising a Fig.37A An array of laser light sources for use in an arrangement;

[0171] Fig.37C is a schematic diagram illustrating in side view a spatial light modulator arrangement including an array of laser light sources, a beam expander, and a scanning mirror;

[0172] Fig.38Ais a schematic diagram illustrating, in a perspective front view, a deformable near-eye display device, the deformable near-eye display device including a stepped extraction interface and an eye tracking arrangement;

[0173] Fig.38B is a schematic diagram illustrating in side view an anamorphic near-eye display device including an eye tracking arrangement having a transmissive aperture disposed at a reflective end;

[0174] Fig.38C is a schematic diagram illustrating, in side view, an anamorphic near-eye display device including an eye tracking arrangement having a partially transmissive mirror disposed at a reflective end;

[0175] Fig.39A is a schematic diagram illustrating a front perspective view of a deformed directional lighting device; and

[0176] Fig.39B is a schematic diagram illustrating a side view of a road scene including a vehicle, the vehicle including a vehicle exterior light device, the vehicle exterior light device including Fig.39A Deformed directional lighting device. DETAILED DESCRIPTION

[0177]

[0046] The terminology associated with optical retarders for the purposes of the present disclosure will now be described.

[0178] In a layer comprising a uniaxial birefringent material, there is a direction that controls the optical anisotropy, while all directions perpendicular to it (or at a given angle thereto) have equivalent birefringence.

[0179] The optical axis of an optical retarder refers to the direction of propagation of light rays in a uniaxial birefringent material where no birefringence is experienced. This is different from the optical axis of an optical system which may be, for example, parallel to the line of symmetry or perpendicular to the display surface along which the principal rays propagate.

[0180] For light propagating in a direction orthogonal to the optical axis, when linearly polarized light with an electric vector direction parallel to the slow axis propagates at the slowest speed, the optical axis is the slow axis. The slow axis direction is the direction with the highest refractive index at the design wavelength. Similarly, the fast axis direction is the direction with the lowest refractive index at the design wavelength.

[0181] For a uniaxial birefringent material with positive dielectric anisotropy, the slow axis direction is the extraordinary axis of the birefringent material. For a uniaxial birefringent material with negative dielectric anisotropy, the fast axis direction is the extraordinary axis of the birefringent material.

[0182] The terms half-wavelength and quarter-wavelength refer to the retarder's 0 The design wavelength of operation is λ 0Typically it may be between 500 nm and 570 nm. In this illustrative embodiment, unless otherwise specified, exemplary retardation values ​​are provided for a wavelength of 550 nm.

[0183] The retarder provides a phase shift between two perpendicular polarization components of a light wave incident thereon, and the phase shift is characterized by the relative phase amount Γ it imparts to the two polarization components; the relative phase amount Γ is related to the birefringence Δn and thickness d of the retarder with a retardation Δn.d by the following equation:

[0184] Γ=2.π.Δn.d / λ 0 Equation 1.

[0185] In Equation 1, Δn is defined as the difference between the extraordinary refractive index and the ordinary refractive index, that is,

[0186] Δn=n e -n o Equation 2.

[0187] For a half-wave retarder, d, Δn, and λ 0 The relationship between is chosen so that the phase shift between the polarization components is Γ = π. For a quarter-wave retarder, d, Δn, and λ 0 The relationship between is chosen so that the phase shift between the polarization components is Γ=π / 2.

[0188] Some aspects of the propagation of light through a transparent retarder between a pair of polarizers will now be described.

[0189] The polarization state (SOP) of light is described by relative amplitude and phase shift between any two orthogonal polarization components. Transparent retarder does not change the relative amplitude of these orthogonal polarization components, but only acts on their relative phase. Net phase shift between the orthogonal polarization components is provided to change SOP, and keeps net relative phase to keep SOP. In current specification, SOP can be referred to as polarization state.

[0190] The linear SOP has a polarization component with non-zero amplitude and an orthogonal polarization component with zero amplitude. The p polarization state is a linear polarization state located in the incident plane of the light including the p polarization state, and the s polarization state is a linear polarization state located orthogonal to the incident plane of the light including the p polarization state. For the linearly polarized SOP incident on the retarder, the relative phase Γ is determined by the angle between the optical axis of the retarder and the direction of the polarization component.

[0191] A linear polarizer transmits a unique linear SOP having a linear polarization component parallel to the electric vector transmission direction of the linear polarizer, and attenuates light having a different SOP. The term "electric vector transmission direction" refers to the non-directional axis of the polarizer, parallel to which the electric vector of the incident light is transmitted, even though the transmitted "electric vector" always has an instantaneous direction. The term "direction" is often used to describe this axis.

[0192] An absorbing polarizer is a polarizer that absorbs one polarization component of incident light and transmits a second, orthogonal polarization component. An example of an absorbing linear polarizer is a dichroic polarizer.

[0193] A reflective polarizer is a polarizer that reflects one polarization component of incident light and transmits a second orthogonal polarization component. An example of a reflective polarizer that is a linear polarizer is a multilayer polymer film stack (such as DBEF from 3M Company). TM or APF TM ) or a wire-grid polarizer (such as the ProFlux from Moxtek TM ). The reflective linear polarizer may further comprise a cholesteric reflective material and a quarter wave retarder arranged in series.

[0194] A retarder disposed between a linear polarizer and a parallel linear analyzing polarizer that introduces no relative net phase shift provides total transmission of light except for residual absorption within the linear polarizer.

[0195] A retarder providing a relative net phase shift between the orthogonal polarization components changes the SOP and provides attenuation at the analyzing polarizer.

[0196] An achromatic retarder may be provided, wherein the material of the retarder is provided with a retardation Δn.d that varies with wavelength λ as follows:

[0197] Δn.d / λ=κEquation 3

[0198] where κ is essentially a constant.

[0199] Examples of suitable materials include modified polycarbonates from Teijin Films.As will be described below, an achromatic retarder may be provided in embodiments of the present application to advantageously minimize color variation between extreme angle viewing directions with low brightness reduction and extreme angle viewing directions with increased brightness reduction.

[0200] Various other terms related to retarders and liquid crystals used in the present disclosure will now be described.

[0201] The liquid crystal cell has a retardation given by Δn.d, where Δn is the birefringence of the liquid crystal material in the cell and d is the thickness of the cell, independent of the orientation of the liquid crystal material in the cell.

[0202] In-plane orientation refers to the orientation of the liquid crystal in a switchable liquid crystal display, where the molecules are oriented substantially parallel to the substrate. In-plane orientation is sometimes referred to as planar orientation. In-plane orientation can typically be provided with a small pre-tilt angle, such as 2 degrees, so that the molecules at the surface of the orientation layer of the liquid crystal cell are slightly tilted as will be described below. The pre-tilt angle is arranged to minimize degeneracy in the switching of the cell.

[0203] In the present disclosure, homeotropic orientation is a state in which rod-like liquid crystal molecules are oriented substantially perpendicular to a substrate. In discotic liquid crystals, homeotropic orientation is defined as a state in which the axis of a columnar structure formed by discotic liquid crystal molecules is oriented perpendicular to a surface. In homeotropic orientation, a pretilt angle is a tilt angle of a molecule close to an alignment layer, and is generally close to 90 degrees, and may be, for example, 88 degrees.

[0204] In a twisted liquid crystal layer, a twisted configuration (also known as a helix structure or a helix) of nematic liquid crystal molecules is provided. The twist can be achieved by means of a non-parallel orientation of the orientation layer. In addition, cholesteric dopants can be added to the liquid crystal material to destroy the degeneracy of the twist direction (clockwise or counterclockwise) and further control the pitch of the twist in the relaxed (usually undriven) state. Super twisted liquid crystal layers have a twist greater than 180 degrees. The twisted nematic layers used in spatial light modulators typically have a twist of 90 degrees.

[0205] Liquid crystal molecules with positive dielectric anisotropy are switched from a planar alignment (such as an A-plate retarder orientation) to a homeotropic alignment (such as a C-plate or O-plate retarder orientation) by means of an applied electric field.

[0206] Liquid crystal molecules with negative dielectric anisotropy are switched from a homeotropic orientation (such as a C-plate or O-plate retarder orientation) to a planar orientation (such as an A-plate retarder orientation) by means of an applied electric field.

[0207] Rod-shaped molecules have positive birefringence, so that as described in Equation 2, n e >n o The discotic molecule has negative birefringence, so that n e <n o .

[0208] Positive retarders (such as A-plate, positive O-plate and positive C-plate) can usually be provided by stretching films or rod-like liquid crystal molecules. Negative retarders (such as negative C-plate) can be provided by stretching films or discotic liquid crystal molecules.

[0209] Parallel cell orientation refers to the orientation directions of the planar alignment layers that are parallel or, more usually, antiparallel. In the case of a pre-tilted homeotropic orientation, the alignment layers may have substantially parallel or antiparallel components. A hybrid oriented cell may have one planar alignment layer and one homeotropic alignment layer. Twisted cells may be provided by alignment layers that do not have a parallel orientation (e.g., oriented at 90 degrees to each other).

[0210] The structure and operation of various variant near-eye display devices will now be described. In this description, common elements have common reference numerals. Note that the disclosure associated with any element is applicable to each device in which the same or corresponding element is provided, after appropriate modification. Therefore, for the sake of brevity, such disclosure is not repeated. Similarly, the various features of any of the following examples can be combined together in any combination.

[0211] It would be desirable to provide an anamorphic near-eye display device 100 having a slim form factor, large freedom of movement, high resolution, high brightness, and a wide field of view. The anamorphic near-eye display device 100 will now be described.

[0212] Figure 1A is a schematic diagram illustrating a front perspective view of a deformed near-eye display device 100; and Figure 1B is a graphic illustration used for Figure 1A Schematic diagram of a front perspective view of a coordinate system arrangement of a deformed near-eye display device 100.

[0213] Figure 1A The figure illustrates a deformable directional lighting device 1000, which is a deformable near-eye display device 100. In the present description, the deformable near-eye display device 100 is provided in the vicinity of the eye 45 to provide light to the eye 45 of the viewer 47. In the illustrative embodiment, the eye 45 can be arranged at a nominal viewing distance e between 5 mm and 100 mm, and preferably between 8 mm and 25 mm, from the output surface of the deformable near-eye display device 100. R Such displays differ from direct-view displays in that the viewing distance is typically greater than 100 mm. R It can be called visual clearance.

[0214] The anamorphic near-eye display device 100 includes an illumination system 240 including a spatial light modulator 48 and arranged to output light, and an optical system 250 arranged to direct light from the illumination system 240 to an eye 45 of a viewer 47. The illumination system 240 is arranged to output light rays 400 including illustrative light rays 401, 402 input into the optical system 250.

[0215] In operation, it is desirable that the spatial pixel data provided on the spatial light modulator 48 be directed as angular pixel data to the pupil 44 of the eye 45. The lens of the viewer's eye 45 relays the angular spatial data to the spatial pixel data at the retina 46 of the eye 45 so that an image is provided by the deformed near-eye display device 100 to the viewer 47.

[0216] The pupil 44 is located in a volume of space (often referred to as the exit pupil 40 or oculomotor box) near the anamorphic near-eye display device 100. When the pupil 44 is located within the exit pupil 40, the viewer 47 is provided with the entire image without missing portions of the image, that is, the image does not appear vignetted at the viewer's retina 46. The shape of the exit pupil 40 is determined at least by the anamorphic imaging properties of the anamorphic near-eye display device and the respective aberrations of the anamorphic optical system. The nominal eye relief distance e is R The exit pupil 40 at may have a dimension e in the lateral direction 195 L and the dimension e in the transverse direction 197 T . Maximum visual clearance distance e Rmax Refers to the maximum distance of the pupil 44 from the deformed near-eye display device 100 where there is no image vignetting. In the embodiment of the present application, increasing the size of the exit pupil 40 refers to increasing the size e L 、e T As will be referred to hereinafter, for example FIG. 4A to FIG. 4C As further described, the enlarged exit pupil 40 enables increased viewer freedom and Rmax increase.

[0217] As hereinafter (for example in FIG. 2A to FIG. 2D and Fig.37B As will be further described in the text, the spatial light modulator 48 includes pixels 222 distributed at least in the lateral direction 195. Figure 1A In the illustrative embodiment of , the illumination system 240 includes a transmissive spatial light modulator 48 that includes an array of spatially separated pixels 222 distributed in a lateral direction 195 (48) and a transverse direction 197 (48). Figure 1A In an embodiment of the present invention, the spatial light modulator 48 is a TFT-LCD, and the illumination system 240 further includes a backlight source 20 arranged to illuminate the spatial light modulator 48.

[0218] The anamorphic near-eye display device 100 further comprises a control system 500 arranged to operate the illumination system 240 to provide light that is spatially modulated in accordance with image data representing an image.

[0219] As described below, the optical system 250 includes a lateral deformation assembly 60, which includes Figure 1AThe lateral lens 61 in the embodiment of the present invention. In this example, the lateral lens 61 includes a cylindrical lens.

[0220] Lateral morphing assembly 60 is arranged to receive light 400 from spatial light modulator 48. Light system 250 is arranged such that light output from laterally morphing assembly 60 is directed in directions distributed in a lateral direction 197 (60).

[0221] exist Figure 1A In an embodiment of the present invention, lateral anamorphic component 60 is a lateral lens 61 extending in a lateral direction 195(60) parallel to lateral direction 195(48) of spatial light modulator 48. Lateral anamorphic component 60 (being lens 61) has positive optical power in a lateral direction 197(60) parallel to direction 197(48) and orthogonal to lateral direction 195(60); and has no optical power in lateral direction 195(60).

[0222] In this disclosure, as will be described below, for example, in FIG. 35 , the term lens most often refers to a single lens element, or most often to a compound lens (group of lens elements); and is arranged to provide optical power. For example, as will be described below Fig.34C As illustrated in , the lens may include a single refractive surface, multiple refractive surfaces, a reflective surface, or may include a catadioptric lens element that combines refractive surfaces and reflective surfaces. The lens may further or alternatively include a diffractive optical element. A transverse lens is a lens that provides optical power in the transverse direction. Typically, a transverse lens does not provide optical power in the lateral direction. A transverse lens may be referred to as a cylindrical lens, although the profile in the cross-section of the surface or surfaces that provide optical power may be different from a segment of a circle, such as parabolic, elliptical, or aspherical.

[0223] The optical system 250 further comprises an extraction waveguide 1 arranged to receive light from the lateral lens 61 and arranged to direct light rays 400 in a cone 491 from the lateral lens 61 in a first direction 191 along the extraction waveguide 1 to the lateral anamorphic component 110. The lateral anamorphic component 110 has a positive optical power in a lateral direction 195.

[0224] The extraction waveguide 1 has opposing rear and front guiding surfaces 6 and 8, and a polarization-sensitive reflector 700 opposite the front guiding surface 8. An example of the polarization-sensitive reflector 700 is a reflective linear polarizer 702. Other types of polarization-sensitive reflectors 700 will be further described below.

[0225] The extraction waveguide 1 further has an input end 2 extending in a lateral direction 195 (60) and a transverse direction 197 (60), the extraction waveguide 1 being arranged to receive light 400 from the illumination system 240 through the input end 2. The input end 2 extends between the edges 22, 24 of the extraction waveguide 1 in the lateral direction 195 and between the opposite rear guide surface 6 and the front guide surface 8 of the extraction waveguide 1 in the transverse direction.

[0226] The deformable near-eye display device 100 is arranged to provide an input linear polarization state 902 for the light 400 guided along the extraction waveguide 1 in the first direction 191 before the light 400 guided along the extraction waveguide 1 in the first direction 191 reaches the polarization-sensitive reflector 700 , and the polarization-sensitive reflector 700 includes a reflective linear polarizer 702 .

[0227] The optical system 250 further comprises a light retro-reflector 140 arranged to reflect light rays 400 in a light cone 491 that has been guided along the extraction waveguide 1 in a first direction 191. The reflected light rays 400 having a polarization state 904 in the light cone 493 are formed to be guided along the extraction waveguide 1 in a second direction 193 opposite to the first direction 191, and such that the reflected cone 493 is guided back through the extraction waveguide 1.

[0228] exist Figure 1A In an embodiment of the present invention, the light retro-reflector 140 is the reflective end 4 of the extraction waveguide 1. In addition, the lateral deformable component 110 includes the light retro-reflector 140. The reflective end 4 of the extraction waveguide 1 has a curved shape in the lateral direction 195 that provides positive optical power, thereby affecting the light in the cone 491 in the lateral direction 195 (110), and does not provide positive optical power in the transverse direction 197 (110). The optical system 250 is therefore arranged so that the light output from the lateral deformable component 110 is guided to directions distributed in the transverse direction 197 (110) and the lateral direction 195 (110). As will be further described below, the curved shape of the reflective end 4 can be a shape of a cross-section of a sphere, ellipse, parabola or other non-spherical shape to achieve the desired imaging of the light from the spatial light modulator 48 to the pupil 44 of the eye 45.

[0229] The extraction element 270 is disposed outside the polarization-sensitive reflector 700 , and includes: a rear guiding surface 6 , which is opposite to the front guiding surface 8 ; and an array of extraction features 170 .

[0230] An array of extraction features 170 is arranged on the rear guide surface 6, which includes a plurality of outwardly protruding prisms 171. The prisms 171 each include at least one extraction facet 172 and at least one draft facet 174. At least one main guide facet 176 may be arranged between the respective at least one extraction facet 172 and at least one draft facet 174. The rear guide surface 6 further includes a guide portion 178 between the prisms 171.

[0231] The array of extraction features 170 comprises extraction facets 172A to 172D, each extraction facet 172 being arranged to reflect light 401 , 402 directed in the second direction 193 through the front guiding surface 8 towards the eye 45 of the viewer 47 .

[0232] As will be referred to hereinafter, for example FIG. 4A to FIG. 4C As further described, an array of extraction facets 172A to 172D are distributed along the extraction waveguide 1 to provide an expansion of the exit pupil 40 in a lateral direction.

[0233] The optical system 250 further includes a polarization conversion retarder 72 disposed between the reflective linear polarizer 702 and the optical retroreflector 140; wherein the operation of the polarization conversion retarder 72 will be described below (e.g., in FIG. 3B to FIG. 3C ) is further described, and is arranged to convert between a linear polarization state 902 propagating in a first direction 191 and a linear polarization state 194 propagating in a second direction 193.

[0234] The operating principle of the anamorphic near-eye display device 100 will now be further described. The optical system 250 has an optical axis 199 and has anamorphic properties in a lateral direction 195 and a transverse direction 197 that are perpendicular to each other and perpendicular to the optical axis 199 .

[0235] Expressed mathematically, for any location within the anamorphic near-eye display device 100, the optical axis direction 199 may be referred to as the O unit vector, the lateral direction 197 may be referred to as the T unit vector, and the lateral direction 195 may be referred to as the L unit vector, where the optical axis direction 199 is the cross product of the lateral direction 197 and the lateral direction 195:

[0236] O=T×L Equation 4.

[0237] The various surfaces of the anamorphic near-eye display device 100 transform or replicate the optical axis direction 199; however, for any given ray, the expression of Equation 4 may be applied.

[0238] Figure 1BThe diagram illustrates the changes in the direction of the optical axis 199, the lateral direction 195, and the transverse direction 197 as the light propagates through the optical system 250. In this description, the lateral direction 195 and the transverse direction 197 are defined relative to the direction of the optical axis 199 in any part of the illumination system 240 or the optical system 250, and are not in constant directions in space. Figure 1B In an embodiment of the present invention, lateral direction 197(60) illustrates lateral direction 197 at lateral anamorphic component 60 formed by lateral lens 61; lateral direction 197(110) illustrates lateral direction 197 at lateral anamorphic component 110; and lateral direction 197(44) illustrates lateral direction 197 at eye 45 of viewer 47. Lateral anamorphic component 60 has lateral direction 195(60) that is the same as lateral direction 195(110) of lateral anamorphic component 110 and lateral direction 195(44) at pupil 44 of eye 45. The Euclidean coordinate system illustrated by the x-direction, y-direction, and z-direction is invariant, while lateral direction 197, lateral direction 195, and optical axis direction 199 may be transformed at various optical components, particularly by reflection from optical components of anamorphic near-eye display device 100.

[0239] We will now describe Figure 1A Further features of the arrangement.

[0240] The optical system 250 may include an input linear polarizer 70 disposed between the spatial light modulator 48 and the extraction feature 170 and between the spatial light modulator 48 and the polarization-sensitive reflector 700 of the extraction waveguide 1; and arranged to pass light having an input linear polarization state 902. Figure 1A In FIG. 5 , an input linear polarizer 70 is arranged between the transverse deformation component 60 and the extraction waveguide 1. The input linear polarizer 70 is an absorbing polarizer, such as a dichroic iodine polarizer arranged to transmit a linear polarization state and absorb an orthogonal polarization state.

[0241] Further, the optical system 250 may include a polarization conversion retarder 72 disposed between the light retro-reflector 140 and the array of extraction features 170. The polarization conversion retarder 72 may be an A-plate having an optical axis direction, which is arranged to convert linearly polarized light into circularly polarized light and to convert circularly polarized light into linearly polarized light. FIG. 6A to FIG. 6B The operation of the input linear polarizer 70 and the polarization conversion retarder 72 will be further described in detail.

[0242] In operation, the extraction waveguide 1 is arranged to guide a light ray 400 propagating in a first direction 191 between the reflective linear polariser 702 and the front guiding surface 8 as illustrated by the zigzag path of the guided light rays 401 , 402 .

[0243] The waveguide 1 further comprises a reflective end 4, which is arranged to receive the guided light rays 401, 402 from the input end 2. The lateral deformation component 110 comprises the reflective end 4 of the extraction waveguide 1, wherein a reflective material is provided on the reflective end 4. The reflective material may be a reflective film, such as ESR from 3M. TM , or it can be a evaporated or sputtered metal material, such as aluminum or silver. Figure 1A In an embodiment, the lateral deformation component 110 is therefore a curved mirror having positive optical power in the lateral direction 195 and no optical power in the transverse direction 197.

[0244] For light rays 400 propagating in the second direction 193, the extraction waveguide is arranged to provide guidance between the front guiding surface 8 and the guiding facets 174 or between the front guiding surface 8 and the guiding portion 178. In the second direction 193, the light is transmitted through the reflective linear polarizer 702.

[0245] For a cone of light 493 propagating in a second direction 193 , the extraction facets 172A to 172D are oriented to extract light directed back along the extraction waveguide 1 in the second direction 193 through the front guide surface 8 and toward the pupil 44 of an eye 45 disposed in the oculomotor box 40 .

[0246] The operation of the near-eye display device 100 as an augmented reality display will now be further described.

[0247] The extraction waveguide 1 is transmissive for light passing through the intermediate surface of the rear guiding surface 6 (including the main guiding facet 176 and the guiding portion 178) so that an on-axis real image point 31 on the real world object 30 is directly viewed via the extraction waveguide 1 by light ray 32. Similarly, a virtual image 34 with aligned on-axis virtual pixels 36 is desirably viewed using virtual light rays 37. Such virtual light rays 37 are provided by on-axis light rays 401 after reflection from the extraction facet 172C to the pupil 44 of the eye 45. Similarly, off-axis virtual light rays 39 for viewing the virtual pixels 38 are provided by off-axis light rays 402 after reflection from the extraction facet 172D. An augmented reality display advantageously having a high transmission of external light rays 32 can be provided.

[0248] The imaging properties of the anamorphic near-eye display device 100 will now be further described using an expanded schematic illustration, in which the described transformation of the coordinate system is removed for illustrative purposes.

[0249] Figure 1C is a schematic diagram illustrating operation of the anamorphic near-eye display device 100 in a transverse plane in side view; Figure 1D is a schematic diagram illustrating, in side view, the operation of the anamorphic near-eye display device 100 in a lateral plane orthogonal to the transverse plane; and Figure 1E is a graphic illustration used for Figure 1A Schematic diagram of a front perspective view of a coordinate system mapping of a deformed near-eye display device 100. Figure 1C to Figure 1E Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0250] For the purpose of illustration, Figure 1C to Figure 1D In Figure 1A to Figure 1B The change in the optical axis direction 199 illustrated in the figure is omitted. Figure 1C to Figure 1D Illustration with expanded illustrative arrangement Figure 1A The deformed near-eye display device 100 is configured to have the same lateral field of view φ as the viewer 47. T and the lateral field of view φ L The operating principle of implementing a near-eye image, that is, for illustration purposes, a square image is provided to the retina 46. The pupil 44 is shown at a common viewing distance e from the output light directing surface 8 of the optical system 250. R Place.

[0251] Figure 1C The diagram illustrates the lateral imaging properties of the anamorphic near-eye display device 100. An illumination system 240 is provided with top illuminated pixels 222T, center illuminated pixels 222C, and bottom illuminated pixels 222B across a lateral direction 197, wherein light rays are output to a lateral anamorphic component 60 having optical power only in the lateral direction, collimating the output from each pixel 222L, 222C, 222R and directing it toward the eye 45. Light ray 460T passes through the pupil 44 of the eye 45 onto the retina 46 of the eye 45 and creates an off-axis image point 461T. Light ray 460C passes onto the retina 46 and creates a center image point 461C, and light ray 460B passes onto the retina 46 and creates an off-axis image point 461B.

[0252] Figure 1DThe diagram illustrates the lateral imaging properties of the anamorphic near-eye display device 100. The illumination system 240 is provided with a right illuminated pixel 222L, a middle illuminated pixel 222M, and a left illuminated pixel 222R across a lateral direction 195, wherein light rays are output to the lateral anamorphic component 110, which has optical power only in the lateral direction, collimates the output from each pixel 222L, 222M, 222R and directs it toward the pupil 44 of the eye 45. Light ray 460L passes through the pupil 44 of the eye 45 onto the retina 46 of the eye 45 and creates an off-axis image point 461L. Light ray 460M passes onto the retina 46 and creates an image point 461M, and light ray 460R passes onto the retina 46 and creates an image point 461R.

[0253] The viewer perceives a magnified virtual image having the same field of view φ in each of the lateral direction 195 and the transverse direction 197 using an optical system 250 arranged between the virtual image 34 and the eye 45 .

[0254] In the deformable near-eye display device 100 of the embodiment of the present application, the distance f between the first principal planes of the lateral deformation component 60 of the optical system 250 is T The distance f between the first principal planes of the lateral deformation component 110 of the optical system 250 is different from L Similarly, for a square output field of view (φ T With φ L The same), the interval D between pixels 222T and 222B in the lateral direction T Different from the spacing D between pixels 222R and 222L in the lateral direction 195 L .

[0255] In this description, the lateral angular magnification M provided by the lateral deformation component 110 of the optical system 250 is L can be given as:

[0256] M L =φp L / P L Equation 5

[0257] And the lateral angular magnification M provided by the lateral deformation component 60 of the optical system 250 T can be given as:

[0258] M T =φp T / P T Equation 6

[0259] where φp L is the angular size of the virtual pixel 36 seen by the eye in the lateral direction 195, P Lis the pixel pitch in the lateral direction 195, φp T is the angular size of the virtual pixel 36 seen by the eye in the lateral direction 197, and P T is the pixel pitch in the lateral direction 197. In the case where the angular virtual pixel 36 is a square, then φp L and φp T are equal, and the angular magnification provided by the lateral deformation component 110 can be given as:

[0260] M L =M T *P T / P L Equation 7.

[0261] The angular magnification M of the lateral anamorphic optical element 110 and the transverse anamorphic optical element 60 is L 、M T The respective optical powers K of the elements 60 and 110 L , K T The spatial light modulator 48 may include a plurality of light beams having a pitch P in the lateral direction 195 and the transverse direction 197. L , P T The pixels are 222, with a pitch of P L , P T The ratio P L / P T With K T / K L Same, K T / K L is the inverse of the ratio of the optical powers of the laterally anamorphic optical element 110 and the transversely anamorphic optical element 60.

[0262] The output coordinate system is Figure 1E , where output light from a center pixel 225 is directed along optical axis 199 ( 60 ) through the lateral deformation component 60 and into the extraction waveguide 1 , from which the light is visible along the optical axis 199 ( 44 ) at the pupil 44 .

[0263] The row 221Tc of pixels 222 extending in the lateral direction 195 through the central pixel 225 is a light fan 493 L Outputted, each ray represents a virtual pixel 38 across a lateral direction 195 at the angle at which it is presented to the pupil 44 .

[0264] The column 221Lc of pixels 222 extending in the lateral direction 197 through the central pixel 225 is a light fan 493 T Outputted, each ray represents a virtual pixel 38 across a lateral direction 197 at the angle at which it is presented to the eye 45.

[0265] For pixels 227 arranged in a quadrant of spatial light modulator 48 , output light 427 is provided to pupil 44 , which is imaged first by lateral anamorphic component 60 and then by lateral anamorphic component 110 .

[0266] We will now describe Figure 1A Illustrative imaging properties of deformed near-eye display device 100.

[0267] Figure 1F It is a graphic illustration Figure 1A Schematic diagram of a field of view plot of the output of a deformed near-eye display device 100 for multi-color illumination.

[0268] Figure 1F is a graph of lateral viewing angles compared to sideways viewing angles. Sideways viewing angle φ L is 60 degrees, and the lateral field of view φ T It is 30 degrees.

[0269] The point with 0 degree lateral field of view is located at the lateral light cone 493 L The point with a 0 degree lateral field of view is located in the lateral light cone 493 T The relative aberrations at various image points are illustrated by blur ellipses 452.

[0270] When output to the eye 45, the width 455 of each blur ellipse 452 indicates the relative blur of a single pixel 227, and therefore represents the relative spot size at the retina 46 of the eye 45 in the lateral direction 195. For illustrative purposes, the height 454 and width 455 of the blur ellipse 452 are illustrated as being 1 / 4 in height. Figure 1F The scale of the drawing is exaggerated and does not represent the actual angular magnitude of the blur at each angular pixel at the pupil 44 .

[0271] The width 455 is the same for each color of the output light because the laterally deforming component 110 is a mirror and therefore its imaging is advantageously achromatic.

[0272] The vertical height 454 of each ellipse indicates the relative blur of a single pixel 227 from the spatial light modulator 48 when output to the eye 45 as an angular cone, and therefore represents the relative spot size at the retina 46 of the eye 45 in the lateral direction 197. Figure 1A The lateral anamorphic component 60 is a refractive optical element, such as a compound lens, and therefore exhibits chromatic aberration. Therefore, the height 454R of the blurred region for the red pixel 222R is different from the height 454B for the blue pixel 222B.

[0273] Thus, when looking up or down, an eye 45 looking at the white point off-axis will see some color blurring for off-axis virtual pixels, but Figure 1A are not side by side in their geometric construction.

[0274] An illustrative arrangement of pixels 222 of spatial light modulator 48 for spatial multiplexing will now be described.

[0275] FIG. 2A to FIG. 2C is illustrated in front view for Figure 1A Schematic diagram of a spatial light modulator 48 including spatially multiplexed red sub-pixels 222R, green sub-pixels 222G, and blue sub-pixels 222B used in a modified near-eye display device 100. FIG. 2A to FIG. 2C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0276] The spatial light modulator 48 may be a transmissive spatial light modulator, such as Figure 1A 22. Alternatively, the spatial light modulator 48 may be a reflective spatial light modulator such as a liquid crystal on silicon (LCOS) or a micro-opto-electromechanical (MOEMS) array of micro-mirrors (such as a DMD from Texas Instruments). Alternatively, the spatial light modulator 48 may be an emissive spatial light modulator using a material system such as an OLED or an inorganic micro-LED. A silicon backplane may be provided to enable high speed addressing of a high resolution array of pixels 222.

[0277] exist FIG. 2A to FIG. 2C , the pixels 222 of the spatial light modulator 48 are distributed in the lateral direction 195 (48) and also in the transverse direction 197 (48), so that the light output from the transverse deformation component 60 is guided to the direction distributed in the transverse direction 197, and the light output from the lateral deformation component 110 is guided to the direction distributed in the lateral direction 195 when it is output toward the pupil 44 of the eye 45.

[0278] The white pixel 222 including the red sub-pixel 222R, the green sub-pixel 222G and the blue sub-pixel 222B is provided spatially separately in the lateral direction 195, and the sub-pixels 222R, 222G, 222B are elongated with a pitch P in the lateral direction. L , spacing P L Greater than the spacing P in the transverse direction 197 T .

[0279] consider FIG. 2A to FIG. 2D implementation plan and Figure 1C to Figure 1D , it may be desirable to provide square white pixels in the final perceived virtual image 34. The pitch P LMagnified by the lateral deformation component to an angle of φ L (with a spatial spacing δ at the retina 46 L ), and the spacing P T Magnified by the lateral deformation component to an angle of φ T (with a spatial spacing δ at the retina 46 T ). Spacing P L , P T The different angular magnifications may be determined to advantageously achieve square angle pixels from the anamorphic near-eye display device 100 .

[0280] The pixels 222 are arranged into columns 211L, wherein the columns 221L are distributed in the lateral direction 195 , and the pixels along the columns 221L are distributed in the transverse direction 197 ; and the pixels 222 are further arranged into rows 221T, wherein the rows 221T are distributed in the transverse direction 197 , and the pixels along the rows 221T are distributed in the lateral direction 195 .

[0281] exist Figure 2A In the embodiment of the present invention, sub-pixels 222R, 222G, 222B are distributed in columns of red pixels, green pixels and blue pixels. Advantageously, vertical image lines and horizontal image lines can be provided with high fidelity.

[0282] exist Figure 2B In an alternative embodiment, sub-pixels 222R, 222G, 222B are distributed along a diagonal line. Advantageously, Figure 2A Compared to the embodiment of the present invention, the reproduction of natural images can be improved.

[0283] Sub-pixels 222R, 222G, 222B may be provided by white light emission and patterned color filters, or may be provided by direct emission of respective colored light. L , the sub-pixel 222 pitch P L Larger than other known arrangements including symmetrical input lenses for thin waveguides.

[0284] exist Figure 2C In an alternative embodiment, a plurality of blue pixels 222B1 and 222B2 may be provided. The blue pixels 222B1, 222B2 may be driven with a reduced current for a desired output brightness. Advantageously, the life of the pixel may be improved, for example when the spatial light modulator 48 is provided by an OLED microdisplay. In other embodiments, additional or alternative white pixels (e.g., without a color filter) or a fourth color (e.g., yellow) may be provided. Color gamut and / or brightness and efficiency may be advantageously achieved.

[0285] Figure 2Dis illustrated in front view for Figure 1A Schematic diagram of a modified near-eye display device 100 having a spatial light modulator 48 for use with pixels 222 for use with time-multiplexed spectral illumination. Figure 2D Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0286] The spatial light modulator 48 may be used for monochromatic illumination. In an alternative embodiment, wide color gamut images may be provided by time sequential illumination (e.g., by red, green, and blue illumination synchronized with red, green, and blue image data provided on the spatial light modulator 48). Advantageously, image resolution may be improved.

[0287] Compared to a non-deformed image projector (in which equal angular magnification is provided between the lateral direction 195 and the transverse direction 197), the present embodiment provides a pixel pitch P L , for a given angular image size and magnification in the lateral direction 197, the pixel pitch P L Such an increased size can advantageously achieve increased brightness, increased efficiency, and reduced alignment tolerances for the spatial light modulator 48 and the illumination system 240.

[0288] In a color filter type spatial light modulator 48, the size of the color filter can be increased. Advantageously, the cost and complexity of the color filter can be reduced. The aperture ratio of the pixel 222 can be improved. In a direct emission display, the size of the emission area can be increased. Advantageously, the cost and complexity of making the pixel can be reduced, and the brightness can be improved. In an inorganic micro-LED spatial light modulator 48, the efficiency loss due to recombination losses at the edges of the pixel can be reduced, and the system efficiency and brightness can be advantageously improved.

[0289] The input to Figure 1A Light input and extraction in the extraction waveguide 1.

[0290] Figure 3A is a schematic diagram illustrating a side view of light input into the extraction waveguide 1; Figure 3B is a schematic diagram illustrating a side view of light propagation along a first direction 191 in an extraction waveguide 1; and Figure 3C is a schematic diagram illustrating a side view of light extraction from the extraction waveguide 1 . FIG. 3A to FIG. 3C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0291] The extraction waveguide 1 includes a waveguide member 111A between the front guide surface 8 and the polarization-sensitive reflector 700 , and a waveguide member 111B between the polarization-sensitive reflector 700 and the rear guide surface 6 .

[0292] Now refer to Figure 3A To describe the lateral light cone 491 input into the extraction waveguide 1 T Input.

[0293] exist Figure 3A In the illustrative embodiment, the input end 2 of the extraction waveguide 1 is inclined, in particular, has a surface normal inclined at an angle δ relative to the surface perpendicular to the rear guide surface 6 and the front guide surface 8, that is, the input end 2 is inclined at an angle δ relative to the first direction 191 and the second direction 193 along the extraction waveguide 1.

[0294] The spatial light modulator 48 and the transverse deformation assembly 60 formed by the transverse lens 61 are tilted at an angle δ relative to the normals of the rear guide surface 6 and the front guide surface 8. The direction of the optical axis 199 (60) passing through the transverse deformation assembly 60 is therefore tilted relative to the first direction 191 and the second direction 193 along the extraction waveguide 1. The direction of the optical axis 199 (60) is generally parallel to the surface normal of the input end 2, so that the optical axis direction 199 (60) is tilted at an angle of 90-δ relative to the first direction 191 and the second direction 193. Figure 1F Advantageously, improved aberrations may be achieved and the height 454 of the pixel blur ellipse 452 may be reduced in at least the lateral direction 197 .

[0295] The optical system 250 further includes a tapered surface 18, which is a surface inclined at an angle x provided near the input end 2 to guide the light beam in the transverse direction 197 from the transverse deformation component 60 into the extraction waveguide 1 at a desired propagation angle. The tapered surface 18 is arranged between the input end 2 and the light guiding surface 8, wherein the surface normal direction is inclined at an angle x relative to a surface perpendicular to the light guiding surface 8. In an alternative embodiment, the tapered surface 18 may be arranged on the rear guiding surface 6.

[0296] Table 1 shows Figure 3A The geometric configuration of the arrangement is for an illustrative embodiment where the extraction waveguide 1 has a refractive index of 1.5.

[0297] Angle compared to the direction 191 along the extraction waveguide 1 Illustrative Embodiments Input 2 tilt angle δ 60° Conical surface 18 inclination angle x 44° <![CDATA[Extract the cone 491 in the material of the waveguide T Half angle, τ]]> 10° Extract the inclination angle α of facet 172 60° Inclination angle ν of the intermediate surfaces 176, 178 0° The incident angle κ of the central output light ray 460C at the output surface 8 is 90°

[0298] Table 1

[0299] The center pixel 222C provides illumination to the lateral deformation component 60 with illustrative light rays 460CA, 460CB. Light ray 460CA is input through the input end 2 without deflection and is guided to just miss the interface 19 of the tapered surface 18 and the front guide surface 8 and is therefore not deflected. However, light ray 460CB is incident on the area of ​​the rear guide surface 6 opposite the tapered surface 18 and is reflected by total internal reflection into the same interface 19, where it is just totally internally reflected, so that light rays 460CA, 460CB overlap and are guided in the first direction 191 along the extraction waveguide 1.

[0300] The extracted facet 172 desirably has a surface normal direction n 172 , surface normal direction n 172 Angle α' (which is inclined at a direction 191 along the extraction waveguide) in the range of 20 to 40 degrees Figure 3A 90-α), preferably at an angle within the range of 25 to 35 degrees, and most preferably at an angle within the range of 27.5 to 32.5 degrees. Advantageously, such an arrangement reduces stray light.

[0301] In an alternative embodiment, the extraction facet 172 can have an angle α' in the range of 50 to 70 degrees, preferably in the range of 55 to 65 degrees, and most preferably in the range of 57.5 to 62.5 degrees. Such an arrangement guides the light ray 460C through the light guiding surface 8 when the light ray 460C has not been reflected from the intermediate surfaces 176, 178 after reflecting from the front light guiding surface 8.

[0302] The embodiment of Table 1 illustrates a design for a refractive index of 1.5. The refractive index of the extraction waveguide 1 can be increased, for example to a refractive index of 1.7 or more. Advantageously, the size of the light cone φ T can be enlarged, and a larger angular image can be seen in the lateral direction.

[0303] The outer pixels 222T, 222B in the lateral direction 195 (48) define a light cone 491 that propagates at an angle τ on both sides of the light rays 460CA, 460CB. T A. 491 T The outer limit of B. The conical surface 18 is provided so that the entire light cone 491 T A is not deflected near the input terminal 2, thereby advantageously achieving reduced crosstalk and high efficiency. T A. 491 T After B passes through the interface 19 , they then recombine to propagate along the extraction waveguide 1 .

[0304] Now refer to Figure 3BTo describe the transverse light cone 491 T Propagation along the extraction waveguide 1 in a first direction 191 .

[0305] consider Figure 3B , the propagation of light rays distributed in the lateral direction 197 in the cone 491 is illustrated. The on-axis light rays 401 from the central pixel 222 of the spatial light modulator 48 are directed by the lateral deformation component 60 into the extraction waveguide.

[0306] The direction of the optical axis 199 ( 60 ) passing through the lateral deformation component 60 is tilted at an angle δ and is tilted at an angle 90-δ with respect to the first direction 191 along the extraction waveguide 1 .

[0307] After interface 19, the light cone 491 T is incident on the reflective linear polarizer 702 at an angle of incidence δ and is reflected so that the replicated light cone 491 T f is provided to propagate along the extraction waveguide 1 in direction 191.

[0308] Figure 3C Illustration of the corresponding reflected light cone 493 T ,493 T f propagation after reflection at the light-reversing component 140. In the transverse direction 197, the lateral deformation component 110 has no optical power and has a surface normal direction n 4 , surface normal direction n 4 Desirably parallel to the first directions 191, 193. The visibility of artifacts caused by stray light (including double images and ghost images) may be reduced.

[0309] Reflected Light Cone 493 T ,493 T f propagates along a second direction 193 at an angle τ about the optical axis 199(60), 199f(60). The corresponding lateral directions 197(60), 197f(60) are also indicated.

[0310] Two cones 493 T ,493 T f includes image data, which is in the cone 493 T ,493 T f, is flipped about direction 191, thus providing degeneracy in the direction of light rays for a given pixel 222 on the spatial light modulator 48. It is desirable to remove such degeneracy so that the cone 493 T ,493 T Only one of f is extracted and the secondary image is not directed to the pupil 44 of the eye 45 .

[0311] Output light 401 propagates by total internal reflection off opposing surfaces 6, 8 until it is incident on guide surface 176 where at least some of the light is reflected, and then incident on extraction facet 172 where at least some of the light is further reflected as will be further described below to cause light cone 493 to T is preferentially directed toward the front guiding surface 8. After refraction at the light guiding surface 8, the cone 495 T The light is directed toward the eye 45 to have a cone 493 T The cone angle is extracted compared to the increased size.

[0312] The extraction facets 172A to 172E are tilted at the same angle α so that Figure 1A Each of the light extraction facets 172A to 172E has a light cone 493 T are parallel, and image blur for light rays 401 extracted to the pupil 44 from different extraction facets 172 across the extraction waveguide 1 is advantageously reduced.

[0313] By comparison, the light cone 493 surrounding the ray 461 T f has an incident angle different from the incident angle δ, and the light ray 461 is incident on the surface 8 and then directly incident on the extraction facet 172 without first reflecting from the guiding surface 176. The difference in the incident angle provides preferential transmission through the extraction facet 172, and the light cone 493 T f is not directed toward the eye 45. Degeneracy is reduced or removed, and image crosstalk or reflected images are advantageously reduced.

[0314] The inclined input end 2 and the inclined lateral deformation component 60 thus provide non-overlapping cones 493 T ,493 T f, wherein one of the cones is preferentially extracted toward the eye 45 and the other is preferentially retained within the extraction waveguide. The tilted input end 2 and the tilted lateral deformation component 60 thus advantageously achieve a single image visible to the eye 45, and ghosting is minimized. In some of the illustrative embodiments described below, the surface normal of the input end 2 is not tilted toward the first direction 191 and the second direction 193, but this is to simplify the illustrations described below and is not a typical arrangement.

[0315] In an alternative embodiment (not shown), the central output light ray 401 may be tilted toward a surface perpendicular to the light guiding surface 8, for example to adjust the extracted light cone 495. T The angular location of the center of the field of view.

[0316] The present embodiment enables improved uniformity of output compared to the near-eye display system described in U.S. Pat. No. 10,048,500 (which is incorporated herein by reference in its entirety). Output uniformity for light from a single extraction facet 172 can be considered, at least in part, by evaluating the angular range over which the light is received after reflection at the light retro-reflector 140. For light propagating along the extraction waveguide 1 in the first direction 191, the light cone 491 is substantially uniform due to the guidance between the polarization-sensitive reflector 700 and the front lightguide surface 8. T and 491 T All ray angles within f are preserved. Such guidance preserves visibility of the ray angles so that the extraction facet 172 provides output for all ray angles. Missing ray angles are reduced or eliminated, and the uniformity of the ray angle field seen by the eye 45 is advantageously increased. Further, for a given desired thickness, the size of the lateral deformable component 60 in the lateral direction is increased. Advantageously, brightness can be increased and / or the thickness of the extraction waveguide 1 can be reduced.

[0317] Pupil dilation in the lateral direction 197 will now be described.

[0318] Figure 4A is a schematic diagram illustrating a side view of light output from a deformed near-eye display device 100 for a single extraction facet 172; Figure 4B is a schematic diagram illustrating a side view of light output from the anamorphic near-eye display device 100 for a plurality of extraction facets 172A-172M to achieve a full light cone input into a viewer's pupil 44 in a lateral direction 197(44); and Figure 4C is a schematic diagram illustrating a front view of light output from an anamorphic near-eye display device 100 for a plurality of extraction facets 172A- 172N for a viewer 47 moving in a lateral direction 197 ( 44 ). FIG. 4A to FIG. 4C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0319] As will now be described, the array of extraction facets 172 is distributed along the extraction waveguide 1 to provide an exit pupil 40 expansion, that is, to increase the size of the eye box 40 in the lateral direction 197. T .

[0320] consider Figure 4A , the single extraction facet 172 is arranged to output a light cone 495 toward the pupil 44 T However, the limited size of pupil 44 determines that only part of the light cone 496 TOnly those rays within the extraction waveguide 1 are received by the eye 45, and the field of view of the image observed on the retina in the lateral direction 197 (44) is smaller than the field of view input into the extraction waveguide 1. It would be desirable to increase the observed field of view.

[0321] consider Figure 4B , a plurality of extraction facets 172A to 172M are provided sufficient to provide extraction from the entire cone 495 T The pupil 44 has a height greater than the pitch of the extraction facets 172. For example, the pitch of the extraction facets 172 may be 1 mm, and the nominal diameter of the pupil 44 may be 3 mm to 6 mm. The pupil receives light from the plurality of extraction facets 172A to 172M, and the observed field of view φ T The same field of view is input into the extraction waveguide 1 at the input. In this restricted case, the exit pupil 40 has a size e T , e T The same height as the pupil 44 .

[0322] consider Figure 4C Further, extraction facets 172A to 172N are provided sufficient to provide movement of pupil 44 between pupil 44A and pupil 44B. T is increased, and the exit pupil expansion in the lateral direction is achieved. T Providing it at the site of the extended pupil 44 advantageously achieves increased comfort of use and full image visibility.

[0323] As in the following FIG. 5A to FIG. 5E As will be described in the following, the lateral deformation component 110 further provides for the expansion of the exit pupil 40 in the lateral direction 195, that is, increasing the size of the eye box 40 in the lateral direction 195. L .

[0324] The imaging properties of the anamorphic near-eye display device 100 in the lateral direction 195 will now be further considered.

[0325] FIG. 5A to FIG. 5C It is a diagram illustrating Figure 1A Schematic diagram of a front view of the light output of a deformed near-eye display device. FIG. 5A to FIG. 5C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0326] Figure 5AThe illustration shows that the non-extraction light guiding region 179A is arranged between the tapered surface 18 and the first extraction facet 172 of the array of extraction facets 172A to 172N; and the non-extraction light guiding region 179B is arranged between the array of extraction facets 172A to 172N and the lateral deformation component 110. The non-extraction guiding sections 179A, 179B can provide an increased height of the extraction waveguide 1 in the first direction 191 without the extraction facets 172. The extraction efficiency is advantageously increased, and the aberration performance of the lateral deformation component 110 is further improved.

[0327] exist Figure 5A In the embodiment of the invention, the eye 45 is aligned in a plan view and out-of-plane rays are not shown, however, such a description provides insight into the operation of the deformable near-eye display device 100 in the lateral direction 195. More than one extraction facet 172 covers the pupil 44 of the eye 45. For example, the extraction facets 172 are spaced 1 mm apart and three to six extraction facets 172 are provided across the pupil 44 of the eye 45, depending on the dilation of the pupil 44 of the eye 45. Advantageously, brightness can be reduced as the eye position 45 changes.

[0328] Pupil 44 receives off-axis light from pixels 222L at the edge of spatial light modulator 48 after reflection from region 478L of anamorphic component 110, which is reflective end 4 of extraction waveguide 1. Although anamorphic component 110 as a whole is a relatively fast optical element, and is therefore susceptible to aberrations, particularly from its edges, the region 478 of anamorphic component 110 that directs light into pupil 44 for any one eye 45 is small, so aberrations from anamorphic component 110 are correspondingly reduced. Consider Figure 1F , a desirably small width 455 of the blur ellipse 452 can be achieved.

[0329] exist Figure 5B In an embodiment, the eye 45 is aligned with the out-of-plane light rays to illustrate the expansion of the exit pupil 40 in the lateral direction 195.

[0330] Light rays 470, 471 are directed from the central pixel 222M of the spatial light modulator 48 across the lateral direction 195 and are transmitted through the lateral anamorphic component 60 formed by a lateral lens 61 having no optical power in the lateral direction 195 and into the extraction waveguide 1. The light rays 470, 471 propagate in the first direction 191 of the extraction waveguide 1 to the light retro-reflector 140, which provides positive optical power in the lateral direction 195 by means of the reflective end 4, which provides the lateral anamorphic component 110.

[0331] Such light rays 470, 471 are reflected from region 478MA of the lateral deformation component 110 into the extraction waveguide 1 in the second direction 193 and are reflected from a plane away from the extraction waveguide 1 at the extraction facet 172A to a viewing distance e R The pupil 44 of the eye 45A is at . The eye 45 collects the light rays 470, 471 and directs them to the same point on the retina 46 to provide a virtual pixel site as described elsewhere herein.

[0332] Similarly for an off-axis pixel 222L offset in the lateral direction 195 (48), light rays 472, 473 are provided at the edge of the spatial light modulator 48 which are directed into the extraction waveguide 1, reflected at region 478LA of the lateral deformation component 110, and reflected by the extraction facet 172A to the eye 45A to provide an off-axis image point on the retina 46 in the lateral direction 195 (44).

[0333] The lateral anamorphic component 110 has positive optical power in the lateral direction 195, which provides collimated light from each image point 222L, 222M. In this way, a lateral distribution of field points is provided across the retina 46 by means of the optical power of the lateral anamorphic component 110, while the transverse anamorphic component 60 has optical power to provide a lateral distribution of field points across the retina 46. Figure 1E At the diagonal field angles illustrated in the imaging diagram for pixel 227, the field point is provided by a combination of the lateral and lateral optical powers of the lateral and lateral deformation components 110 and 60, respectively.

[0334] Figure 5C The diagram illustrates the exit pupil expansion in the lateral direction 195 and in the transverse direction 197. Light rays 474, 475 for pixels 222R, 222L are directed to pupil 44B by reflecting from regions 478RB, 478LB, respectively, of lateral deformation component 110. Pupil 44B is offset from pupil 44A in the lateral direction 195, wherein light rays 474, 475 are reflected by at least extraction facet 172A. The width e of exit pupil 40 is L Therefore, the relatively large width of the lateral deformation component 110 is increased so that the area 478 can be arranged at the desired width. The viewing freedom of the eye 45 in the exit pupil 40 is improved, which advantageously improves the viewing comfort for the eye 45 while achieving the entire field of view in the lateral direction.

[0335] Figure 5C Further illustration of pupil expansion in the lateral direction 197. Figure 4C As discussed, light reflected from extraction facet 172D is directed to pupil 44C, which has a different height than pupil 44A.

[0336] Figure 5D is a schematic diagram illustrating a front view of the extraction waveguide 1 and the aligned exit pupil 40. Figure 5D Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0337] Figure 5D The illustrative embodiment of FIG. 4 illustrates the position of the exit pupil 40 with edge positions 41L, 41R and with edge positions 41T, 41B, as shown in FIG. Figure 5B As illustrated in FIG. 1 , the edge positions 41L, 41R are provided by the expansion of the exit pupil 40 in the lateral direction 195, as shown in FIG. Figure 4B As illustrated in FIG, edge positions 41T, 41B are provided by expansion of exit pupil 40 in lateral direction 197 .

[0338] The size of the exit pupil 40 is at least partially determined by the desired field of view φ. L ,φ T and visual clearance R was further determined.

[0339] Exit pupil 40 expansion will now be further described using the illustrated expanded geometry.

[0340] Figure 5E is a schematic diagram illustrating a side view of an expanded imaging system arranged to image in a lateral direction 197, wherein reflective extraction features (e.g., extraction facets 172) are provided; Fig. 5F is a schematic diagram illustrating a top view of a deployed imaging system arranged to image in a lateral direction; and Figure 5G is a schematic diagram illustrating a side view of an expanded imaging system arranged for imaging in a lateral direction, in which an array of extraction facets 172 is provided, but the description applies similarly to other reflective extraction features. Figure 5E to Figure 5G Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0341] Figure 5E to Figure 5G yes Figure 1A 1 is an expanded representation of a deformed near-eye display device 100 and is provided for illustration purposes only.

[0342] consider Figure 5E, light from the spatial light modulator 40 illuminates the lateral anamorphic component 60 and inputs the light into the expanded waveguide member 111A in direction 191. The light passes through the lateral anamorphic component 110 without modification and is transmitted to the expanded waveguide member 111B in direction 193. Light beams 420T, 420C, 420B are provided across the lateral direction for pixels 222T, 222C, 222B, respectively, on the spatial light modulator 48. The pupil 44 of the eye 45 observes the entire cone of light if located in the cone 422, which is close to the lens and is therefore invisible to the eye 45. This is similar to Figure 4A Illustrative embodiments of the present invention.

[0343] consider Fig. 5F , light from the spatial light modulator 40 illuminates the lateral morphing component 110 and inputs the light into the expanded waveguide member 111A in the direction 191. The light cones in the lateral direction from the pixels 222L, 222M, 222R are collimated by the lateral morphing component 110 and transmitted to the expanded waveguide member 111B in the direction 193. Light beams 420L, 420M, 420R are provided across the lateral direction. The pupil 44 of the eye 45 observes the entire light cone if located in the cone 424, which is visible to the eye outside the expanded waveguide member 111B because the width of the lateral morphing component 110 is much larger than the width of the lateral morphing component 60. This is similar to Figure 5B Illustrative embodiments of the present invention.

[0344] The effect of the extracted features 170 on pupil dilation in the lateral direction 197 will now be further illustrated.

[0345] and Figure 5E compared to, Figure 5G The diagram illustrates an array of extraction features 170 distributed along the extraction waveguide 1 to provide an expansion of the exit pupil 40. Each of the extraction features 170A to 170N effectively provides a replicated image 48R, 60R of the spatial light modulator 48 and the lateral deformation component 60, respectively. Such replicated images 48R, 60R further provide Figure 5E The replicated light cone 420 expands the effective width of the final light cone 420TR, 420BR. Such replication provides a replicated cone 426, and the pupil 44 receives light from within the cone 426 for the full field angle.

[0346] Cones 422, 424, 426 schematically represent the exit pupil 40 of the deformable near-eye display device in the lateral direction 195 or transverse direction 197. Thus, compared to the exit pupil 40 represented by cone 422 (by comparison, the exit pupil 40 would be provided to a conventional micro-projector without pupil expansion), the exit pupil 40 expansion is achieved by the lateral deformable component 110 and by the Figure 1AThis is achieved by including an array of extraction features 170A to 170N that extract facets 172A to 172N.

[0347] We will now describe Figure 1A Polarized light propagation in an illustrative embodiment of.

[0348] Fig. 6A It is a graphic illustration Figure 1A Schematic diagram of a side view of polarized light propagation in a deformed near-eye display device 100; Figure 6B It is a graphic illustration Figure 1A A schematic diagram of a front view of polarized light propagation in a deformed near-eye display device 100; and Figure 6C It is illustrated by FIG. 6A to FIG. 6B Schematic diagram of the alignment direction of the polarization control components. FIG. 6A to FIG. 6C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0349] The illumination system 240 is arranged to output unpolarized light, or is arranged to output light having an input linear polarization state 902; and the optical system 250 includes an input linear polarizer 70 disposed between the spatial light modulator 48 and the polarization-sensitive reflector 700, the polarization-sensitive reflector 700 including the reflective linear polarizer 702. Further, the input linear polarizer 70 is disposed between the spatial light modulator 48 and the extraction waveguide 1.

[0350] The input linear polarizer 70 is arranged to pass light having an input linear polarization state 902, FIG. 6A to FIG. 6C In an embodiment, the input linear polarization state 902 is an s-polarization state in the extraction waveguide 1; that is, the polarization state 902 has an electric vector transmission direction 900, which provides a linear polarization state 902 of s-polarization parallel to the lateral direction 195.

[0351] The reflective linear polarizer 702 is arranged to reflect light having an input linear polarization state 902 directed in a first direction 191 so that the polarization-sensitive reflector 700 is arranged to direct light in the first direction 191. Reflection of the directed light from the front light directing surface 8 is provided by total internal reflection, while reflection of the directed light from the reflective linear polarizer 702 is by means of metal reflection in the case of a wire grid type reflective polarizer (such as from Moxtek), or by means of a stack of Fresnel reflections in the case of a dielectric stack type reflective polarizer (such as APF from 3M Company).

[0352] The polarization-converting retarder 72 is disposed between the light retro-reflector 140 and the array of extraction features 170, and is further disposed between the light retro-reflector 140 and the reflective linear polarizer 702. The polarization-converting retarder 72 has a quarter-wavelength retardation at a visible wavelength (e.g., 550 nm), or may be tuned for another visible wavelength, for example, to match the peak brightness of a monochrome display.

[0353] The retardation of the polarization-converting retarder 72 may be different from a quarter wavelength, but may be selected to provide the same effect. For example, the polarization-converting retarder 72 may have a retardation of, for example, three quarter wavelength or five quarter wavelength.

[0354] The retarder 72 may include a stack of composite retarders arranged to achieve operation of a quarter wave retarder over an increased spectral band, for example including a Pancharatnam stack (which is different from the Pancharatnam-Berry lens described below). Advantageously, color uniformity may be improved. The polarization converting retarder 72 may be provided with additional retarder layers to increase the field of view of the quarter wave retarder function to advantageously achieve improved uniformity across the viewing field.

[0355] Polarization conversion retarder 72 is most commonly used to provide polarization modification to provide a conversion from polarization state 902 to polarization state 904 for light 401 .

[0356] Figure 6C The diagram illustrates the propagation of polarization states and the alignment of various optical components. The polarizer 70 has an electric vector transmission direction 870 at 0 degrees, the reflective linear polarizer 702 has an electric vector transmission direction 701 at 90 degrees, and the polarization conversion retarder 72 is a quarter wave retarder with an optical axis direction 872 aligned at 45 degrees. In operation, the polarization state 902 is guided by reflection from the reflective linear polarizer 702 and converted to a left circular polarization state 922 by the polarization conversion retarder 72. The phase change upon reflection by the mirror of the optical retroreflector 140 provides a reflected right circular polarization state 924. During the second pass through the polarization conversion retarder 72 to propagate the light in the second direction 193, the polarization state 924 is converted to a linear polarization state 904, which is transmitted to the rear guiding surface 6 by the reflective linear polarizer 702.

[0357] exist FIG. 6A to FIG. 6BIn an alternative embodiment, the polarization conversion retarder 72 is provided within the extraction waveguide 1 and across the input aperture of the lateral deformation component 110. Such an arrangement may be suitable for an extraction waveguide 1 in which the light retro-reflector 140 is assembled as a separate component separate from the extraction region of the extraction waveguide 1 including the extraction features 170. In such an arrangement, the reflector surface of the light retro-reflector 140 is not arranged on the polarization conversion retarder 72. The surface quality of the light retro-reflector 140 can be improved. The modulation transfer function contrast can be advantageously improved and a clearer image can be achieved. For illustrative purposes, in Figure 6B , the extraction facet 172 is shown, and the draft facet 174 and the major guide surface 176, as well as the guide portion 178 are omitted.

[0358] consider FIG. 6A to FIG. 6B , for the exemplary light ray 401, the polarization conversion retarder 72 is arranged to convert the polarization state 902 of the light passing through the polarization conversion retarder 72 between the linear polarization state 902 and the circular polarization state 922, and convert the polarization state 902 of the light passing through the polarization conversion retarder 72 between the circular polarization state 924 and the linear polarization state 904 after reflection at the light retro-reflector 140 of the laterally deformable component 110. The polarization conversion retarder 72 and the light retro-reflector 140 are arranged in combination to rotate the input linear polarization state 902 of the light directed in the first direction 191 so that the light directed in the second direction 193 and output from the polarization conversion retarder 72 has an orthogonal linear polarization state 904 that is orthogonal to the input linear polarization state 902.

[0359] Fig. 6A The illustration shows that the front guiding surface 8 and the polarization-sensitive reflector 700 are arranged to guide light in a first direction 191. The polarization-sensitive reflector 700 is further arranged to pass light rays 401, 404, 406 having orthogonal linear polarization states 904 guided in a second direction 193.

[0360] The main guiding facets 176 and the guiding portions 178 of the front guiding surface 8 and the rear guiding surface 6 are arranged to guide the light rays 404, 406 in the second direction 193. Figure 6B In the regions 179A, 179B illustrated in FIG. 1 , the polarization-sensitive reflector 700 and the extraction facet 170 may be omitted, and the guidance in the first direction 191 and the second direction 193 is between the front guiding surface 6 and the rear guiding surface 8 , which may be planar and parallel.

[0361] In other words, the optical system 250 includes an input linear polarization state 70 and a polarization conversion retarder 72, the input linear polarizer 70 being disposed between the spatial light modulator 48 and the array of extraction features 170, the polarization conversion retarder 72 being disposed between the light retroreflector 140 and the array of extraction facets 170, the polarization conversion retarder 72 being arranged to convert the polarization state of light passing through the polarization conversion retarder 72 between linear polarization states 902, 904 and circular polarization states 922, 924, respectively. Light 401 is extracted at the extraction facet 172 in polarization state 904.

[0362] In operation, light rays 401 are not incident on the rear light directing surface 6. Light losses and stray light are reduced. Advantageously, efficiency and image contrast are improved. Glow directed towards an external observer is reduced.

[0363] During manufacturing, the extraction waveguide 1 can be formed and the reflective linear polarizer 702 is formed over at least the planar portion 6P of the rear surface 6. The plurality of prisms 171 can be formed, for example, by embossing, UV casting, injection molding or other known techniques. The plurality of prisms 171 can be attached to the reflective linear polarizer 702 after molding, or can be molded in situ. Alternatively, the plurality of prisms 171 can be formed on the reflective linear polarization state 702, and the reflective linear polarizer 702 can be attached to the planar portion 6P of the extraction waveguide 1.

[0364] Considering an external object 30, unpolarized light from the real world object 30 is guided through the extraction waveguide 1. An optional external polarizer 90 having a p-polarized electric vector transmission direction 90 can be provided, the optional external polarizer 90 transmits a linear polarization state 920 aligned with the polarization state 904, and can be arranged so that the extraction waveguide 1 is arranged between the object 30 and the eye 45. The external polarizer 90 can further reduce the background object brightness compared to the brightness of the deformable near-eye display device 100. Advantageously, the image contrast of the superimposed virtual image can be improved and double imaging can be reduced. Further, reflections from the reflective linear polarizer 702 can be reduced, thereby advantageously improving the visibility of the eye 45 to increase social interaction.

[0365] Fig.6D is a schematic diagram illustrating a side view of polarized light propagation in a deformed near-eye display device 100, wherein the polarization state 902 propagating along the first direction 191 is orthogonal to Fig. 6A Arrangement; Fig. 6E It is a graphic illustration Fig.6D A schematic diagram of a front view of polarized light propagation in a deformed near-eye display device 100; and Fig. 6F It is illustrated by FIG. 6D to FIG. 6E Schematic diagram of the alignment direction of the polarization control components. FIG. 6D to FIG. 6F Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0366] exist FIG. 6D to FIG. 6E In an alternative embodiment, the input linear polarizer 70 is arranged in the extraction waveguide 1. FIG. 6A to FIG. 6B Compared to the embodiment of FIG. 1 , depolarization that may occur from scattering in region 179A of the extraction waveguide 1 can be reduced, thereby advantageously improving contrast. Further, the polarization conversion retarder 72 is arranged on the end 4 of the extraction waveguide 1. Advantageously, the complexity of the construction can be reduced.

[0367] Furthermore, FIG. 6A to FIG. 6B Compared with the s-polarization state of the input linear polarization state 902, the p-polarization state in the extraction waveguide 1 is extracted, and FIG. 6A to FIG. 6B Compared to the p-polarization state, the linear polarization state 904 is an s-polarization state.

[0368] The transmission and reflectivity characteristics of reflective linear polarizer 702 may be different for incident s-polarized light and p-polarized light. FIG. 6D to FIG. 6E In the illustrative example of FIG. 1 , for light propagating in the second direction 193, some of the s-polarized light of polarization state 904 may be reflected by the reflective linear polarizer 702, rather than being transmitted, and may be guided between the reflective linear polarizer 702 and the front guiding surface 8, thereby FIG. 6A to FIG. 6B Compared to the embodiment of the present invention, improved extraction uniformity is advantageously achieved.

[0369] Alternative embodiments of the polarization-sensitive reflector 700 will now be described. In the following examples, specific examples of the polarization-sensitive reflector 700 are shown (e.g., Figure 1A The reflective linear polarizer 702, Fig. 7A The dielectric stack 712 and Fig. 8A In the embodiment of the present invention, the nematic liquid crystal layer 722 in the embodiment of the present invention is shown, but this is not limiting, and in general, any of the polarization-sensitive reflectors disclosed herein can be applied to the following examples alternatively. Similarly, the various features of the following examples can be combined in any combination.

[0370] The polarization-sensitive reflector 700 including a stack of dielectrics will now be described.

[0371] Fig. 7A is a schematic diagram illustrating a side view of the operation of an alternative polarization-sensitive reflector 700 that includes a thin-film dichroic stack 712 . Fig. 7AFeatures of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0372] The polarization-sensitive reflector 700 may include at least one dielectric layer 714 having a different refractive index than the waveguide members 111A, 111B and arranged to provide polarization-sensitive reflection to incident illumination having polarization states 902, 904, such as by Fresnel reflection or total internal reflection, and Fig. 7A In an embodiment, at least one dielectric layer 714 includes a stack 712 of dielectric layers 714A to 714E.

[0373] For the illustrative embodiment in Table 2, the dielectric stack 712 includes a plurality of dielectric layers 714A to 714E. Light ray 401 (191) having a polarization state 902 of s-polarization propagating in a first direction 191 is incident on the dielectric stack 712 and is reflected as light ray 411. Light ray 401 (193) propagating through the extraction waveguide 1 in a polarization state 904 of p-polarization in a second direction 193 is at least partially transmitted through the dielectric stack 712.

[0374] item Illustrative Materials Refractive Index Thickness(nm) Waveguide member 11A PMMA 1.50 - Dielectric layer 174A <![CDATA[TiO 2 ]]> 2.6 54 Dielectric layer 174B <![CDATA[SiO 2 ]]> 1.5 181 Dielectric layer 174C <![CDATA[TiO 2 ]]> 2.6 55 Dielectric layer 174D <![CDATA[SiO 2 ]]> 1.5 181 Dielectric layer 174E <![CDATA[TiO 2 ]]> 2.6 55 Waveguide member 11B PMMA 1.49 -

[0375] Table 2

[0376] Figure 7B is a schematic graph illustrating the variation of thin film stack transmission versus wavelength for incident s-polarized polarization state 902 and p-polarized polarization state 904 . Figure 7B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0377] The profiles 716S and 716P are respectively the normal n from the dielectric layer 712 for the s-polarization state 902 and the p-polarization state 904. 712 Average transmission over a 20 degree cone angle at a nominal angle of incidence of 60 degrees. At visible wavelengths, the dielectric stack 712 can achieve high reflectivity for light 401 (191) propagating in the first direction 191 and high transmission for light 401 (193) propagating in the second direction 191.

[0378] The arrangement of Table 2 achieves high efficiency of light propagation in the first direction. Compared to a wire grid polarizer, the dielectric stack 712 can be conveniently provided on the waveguide member 111A or the waveguide member 111B by known deposition techniques. The dielectric stack 712 can have a low thickness and does not require a thermally and mechanically stable substrate for deposition, thereby advantageously achieving reduced costs. The absorption losses in the dielectric stack can be lower than those for a wire grid polarizer, thereby advantageously achieving improved efficiency.

[0379] The number and thickness of the layers of Table 2 can be modified to achieve reduced cost or increased bandwidth in wavelength and reflectivity for a desired illumination angle cone.

[0380] Further, some of the polarization states 904 may be reflected by the dielectric stack 712 so that the length over which uniform extraction occurs may be increased.

[0381] It would be desirable to provide improved uniformity across the dielectric stack 712 .

[0382] Figure 7C is a flow chart illustrating pixel-level compensation for correcting transmission of the dielectric stack 712 and, more generally, for the polarization-sensitive reflector 700 described elsewhere herein. Figure 7C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0383] For a given ray angle in a lateral direction 193 within the extraction waveguide 1, the reflectivity of the dielectric stack 712 can be varied. Such a variation can provide a brightness variation in the lateral direction. In a first step S1, the angle of incidence of the ray 401 for the lateral pixel 222 in the row 221T onto the dielectric stack 712 is calculated. In a second step S2, the transmission of the ray 401 in the first direction 191 and the second direction 193 is calculated. In a third step S3, the output of the pixel 222 in the row 221T is modified to compensate for the varying transmission at the dielectric stack 712 corresponding to the ray 401 for the row 221T. Advantageously, improved uniformity of the image at the retina 47 of the eye 45 can be achieved.

[0384] The polarization-sensitive reflector 700 including a liquid crystal layer will now be described.

[0385] Fig. 8A is a schematic diagram illustrating a front view of a deformed near-eye display device 100 including an alternative polarization-sensitive reflector 700 including an in-plane nematic liquid crystal layer 722; Figure 8B is illustrated in top view Fig. 8A A schematic diagram of a liquid crystal layer of a polarization-sensitive reflector; and Figure 8C is illustrated in side view Fig. 8A Schematic diagram of the liquid crystal layer of the polarization-sensitive reflector. FIG. 8A to FIG. 8C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0386] and Figure 1A (wherein the polarization-sensitive reflector 700 is a reflective linear polarizer 702) or Fig. 7A Compared to the embodiment of FIG. 7 (wherein the polarization-sensitive reflector 700 is a dielectric stack 712), in FIG. 8A to FIG. 8C In an alternative embodiment of the invention, the polarization-sensitive reflector 700 includes a liquid crystal layer 722 including liquid crystal molecules 724 having an optical axis direction 725. The liquid crystal molecules may be nematic liquid crystal molecules and are arranged in an aligned layer. The liquid crystal molecules 724 are arranged between opposing first and second alignment layers 726A and 726B, the first and second alignment layers 726A and 726B having alignment directions 727A and 727B, respectively having pretilt angles 728A and 728B that provide alignment of the optical axis direction 725 of the liquid crystal molecules 724.

[0387] The liquid crystal molecules may be uncured. Alternatively, the molecules may include cured liquid crystal molecules, such as reactive polyarylate molecules that have been cured in UV illumination after alignment. The alignment layers 726A, 726B may be removed after curing so that the nematic liquid crystal layer 722 does not include the alignment layers 726A, 726B.

[0388] The pretilt angles 728A, 728B may be, for example, 2 degrees, and may be anti-parallel to reduce the presence of alignment disclination, thereby advantageously reducing scattering. In alternative embodiments, the pretilt angles 728A, 728B may be larger, for example 88 degrees, or may be different. The liquid crystal molecules may have a FIG. 8A to FIG. 8C The dielectric anisotropy may be positive as illustrated in FIG, or it may have negative dielectric anisotropy. Fig. 8A , the optical axis direction 725 is aligned with a component 725p in the plane of the liquid crystal layer 722, the component 725p being orthogonal to the direction 191 along the extraction waveguide 1. In other embodiments (not illustrated), the optical axis direction 725 may be aligned with a component 725p in the plane of the liquid crystal layer 722, the component 725p being parallel to the direction 191 along the extraction waveguide.

[0389] We will now further describe Fig. 8AOperation of the extraction waveguide 1.

[0390] Fig. 9A is a schematic diagram illustrating a side view of the operation of an alternative polarization-sensitive reflector 700 including a nematic liquid crystal layer 722 for a p-polarized light polarization state 902 propagating along an extraction waveguide 1 in a first direction 191; and Fig. 9B It is a graphic illustration Fig. 9A Schematic diagram of a side view of the operation of an alternative polarization-sensitive reflector 700 for an s-polarized light polarization state 904 propagating along the extraction waveguide 1 in the second direction 193 . FIG. 9A to FIG. 9B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0391] An illustrative embodiment of a polarization-sensitive reflector 700 including a nematic liquid crystal layer 722 is shown in Table 3.

[0392] item Descriptive Value Refractive index of waveguide member 111A 1.80 <![CDATA[Ordinary refractive index of liquid crystal molecules 725, n o > 1.50 <![CDATA[Extraordinary refractive index of liquid crystal layer molecules 725, n e > 1.80 Refractive index of waveguide member 111A 1.80 The critical angle at the interface between the component 111A and the nematic liquid crystal layer 722, qc 56°

[0393] Table 3

[0394] exist Fig. 9A In an alternative embodiment of the present invention, the polarization state 902 of the light ray 401 (191), 472 (191) sees the ordinary refractive index of the liquid crystal molecule 724 and undergoes total internal reflection. For the incident polarization state 902, the light cone 491 T The critical angle θ at the interface between the waveguide member 111A and the nematic liquid crystal layer 722 is c Limit the cone size.

[0395] Therefore, cone 491 T The light ray 401 ( 191 ) inside is guided between the polarization-sensitive reflector 700 and the light guiding surface 8 .

[0396] Fig. 9B The diagram illustrates that light 401 ( 193 ) propagating in the second direction 193 is index matched at the interface with the nematic liquid crystal layer 722 , and is transmitted for incidence on the rear guiding surface 6 .

[0397] Advantageously, the nematic liquid crystal layer 722 can be conveniently manufactured with high uniformity and low cost, and is provided in a thin layer between the waveguide members 111A, 111B.

[0398] It may be desirable to provide an increased field of view in the lateral direction 197 .

[0399] Fig. 10Ais a schematic diagram illustrating a side view of the operation of an alternative polarization-sensitive reflector 700 including a cholesteric liquid crystal layer 732 for a p-polarized light polarization state 902 propagating along an extraction waveguide 1 in a first direction 191; and Fig. 10B It is a graphic illustration Fig. 9A Schematic diagram of a side view of the operation of the cholesteric liquid crystal layer 732 on the polarization state 904 of s-polarized light propagating in the second direction 193 along the extraction waveguide 1. FIG. 10A to FIG. 10B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0400] and Fig. 9A Compared with the implementation scheme, Fig. 10A In an alternative embodiment of , the polarization-sensitive reflector 700 includes a cholesteric liquid crystal reflector 732 including a layer 733 of a cholesteric liquid crystal material 734 .

[0401] The deformable near-eye display device 100 further includes a polarization conversion retarder 736A arranged between the front guiding surface 8 and the cholesteric liquid crystal retarder 733, wherein the polarization conversion retarder 736A is arranged to convert the polarization state of light passing through the polarization conversion retarder 736A between the linear polarization state 902 and the circular polarization state 938, and the polarization conversion retarder 736A and the cholesteric liquid crystal layer 733 are arranged in combination to reflect the input linear polarization state 902 of the light guided in the first direction 401 (191) and transmit the linear polarization state 904 of the light 401 (193) guided in the second direction. The deformable near-eye display device further includes a polarization conversion retarder 736B arranged between the rear guiding surface 6 and the cholesteric liquid crystal retarder 733, wherein the polarization conversion retarder 736B is arranged to convert the polarization state of light passing through the polarization conversion retarder 736B between the linear polarization state 904 and the circular polarization state 939.

[0402] In other words, layer 733 is arranged between opposing polarization-converting retarders 736A, 736B, which are arranged to convert off-axis polarization state 902 to circular polarization state 938 and circular polarization state 938 to linear polarization state 902; and to convert off-axis polarization state 904 to circular polarization state 939 and circular polarization state 939 to linear polarization state 904. Polarization-converting retarders 736A, 736B may be quarter-wave retarders when considering off-axis illumination of light 401, and thus may have a different retardation than quarter-wave retarders for on-axis light.

[0403] Polarization conversion retarders 736A, 736B advantageously provide linear polarization states guided within the extraction waveguide 1, which improves efficiency and uniformity. By comparison, guiding of circular polarization states (where polarization conversion retarders 736A, 736B are omitted) causes depolarization of light during guiding and reduces efficiency.

[0404] In operation, incident polarization state 902 is incident on polarization conversion retarder 736A, and polarization state 938 is output and incident on layer 733 of cholesteric phase material 734, which is aligned with the polarizing force and pitch to reflect incident light ray 401. The reflected polarization state from layer 733 has not undergone a phase shift (as would occur with a mirror), and so is not as good as, for example, Fig. 6A Compared to the reflected polarization states 922, 924 described in FIG. 1 , polarization state 938 is not reflected when reflected from layer 933.

[0405] The cholesteric liquid crystal layer 733 may have a chirped pitch structure to achieve increased bandwidth, and may have different orientations to improve angular reflectivity.

[0406] As described elsewhere herein, output polarization state 902 is provided after light 401 ( 191 ) makes a second pass through polarization-converting retarder 736A and the light is guided along extraction waveguide 1 between cholesteric liquid crystal reflector 732 and front light guiding surface 8 .

[0407] Fig. 10B Propagation in the second direction 193 is illustrated with polarization state 904 incident on cholesteric liquid crystal reflector 732. Circular polarization state 939 is incident on layer 939 and is transmitted and output into waveguide member 111B as the same polarization state 904 for illuminating a second light guiding surface.

[0408] and FIG. 9A to FIG. 9B Compared with the implementation scheme, the cone angle 491 T The size can be increased, and the field of view φ in the lateral direction T Further, the refractive index of the waveguide members 111A, 111B can be reduced, thereby advantageously reducing the cost.

[0409] It may be desirable to improve the efficiency and uniformity of the polarization-sensitive reflector 700 .

[0410] FIG. 11A to FIG. 11C is a schematic diagram illustrating side views of various arrangements of the polarization-sensitive reflector 700 . FIG. 11A to FIG. 11C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0411] The polarization-sensitive reflector 700 may further include a plurality of polarization-sensitive reflector elements. Fig.11A The diagram illustrates a dual-layer polarization-sensitive reflector 700, Fig. 11B The diagram illustrates a three-layer polarization-sensitive reflector 700, and Fig. 11C A four-layer polarization-sensitive reflector 700 is illustrated. Each of the polarization-sensitive reflectors 700A to 700D may include a reflective linear polarizer 702, a dielectric stack 712, a nematic liquid crystal layer 722, or a cholesteric liquid crystal layer 732. Other known polarization-sensitive reflective layers may alternatively be provided.

[0412] Advantageously, the efficiency of differentiation between polarization states 902, 904 propagating in the first direction 191 and the second direction 193 may be improved or modified. System efficiency and image uniformity across the exit pupil 40 may be improved.

[0413] In an illustrative embodiment, the polarization-sensitive reflector 700A may include a reflective linear polarizer 702, and the polarization-sensitive reflector 700B may include a dielectric stack 712. The dielectric stack 712 of the polarization-sensitive reflector 700B may have a high reflectivity for the light 401 (191), and any remaining light that passes through the dielectric stack is reflected by the reflective linear polarizer 702. Advantageously, the light is efficiently guided in the first direction 191 between the polarization-sensitive reflector 700 and the front light guiding surface 8. Because most of the reflectivity is provided by the dielectric stack 712, absorption losses from reflection at the reflective linear polarizer 702 are reduced, and the efficiency of the guidance along the extraction waveguide 1 is improved.

[0414] For light ray 401 (193), dielectric stack 712 can be arranged to provide a residual reflectivity of the incident p-polarization state. Such residual reflectivity provides increased light guided along extraction waveguide 1 in the second direction after first reflection at polarization-sensitive reflector 700, and advantageously achieves improved uniformity.

[0415] We will now describe Figure 1A In the following examples, specific examples of arrays of extraction features 170 are shown (e.g., Figure 1A Prism 171, Fig.12F Steps 12, Fig.15 Plate 174, Fig. 20B ), but this is not limiting, and in general, any one of the extraction features 170 disclosed herein can be applied to the following examples alternatively. Similarly, the various features of the following examples can be combined together in any combination.

[0416] Fig. 12A is a schematic diagram illustrating a side view of the operation of an array of extraction features 170, each of which includes a prism 171, the prism 171 including an extraction facet 172, a guiding facet 176, and a draft facet 174, wherein a pitch p(x) of the prisms 171 varies with a distance x from the light retroreflector 140 along the extraction waveguide 1; and wherein a surface normal direction n of the draft facet 174 174 The surface normal direction n of the guide portion 178 of the rear light guide surface 6 178 Tilt at a 90 degree angle. Fig. 12A Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0417] exist Fig. 12A In an alternative embodiment, the facets 172 are extracted with respect to the direction n 178 Tilt at angle α (and Figure 3A ) to provide a deflection of light 460C (193) propagating in a second direction 193 from the center pixel row 222C in a lateral direction 197 so that the light reflected by the total internal reflection at the main guiding facet 176 and then the extraction facet 172 is guided perpendicular to the front light guiding surface 8. The center pixel row 222C will then be provided along the center line of the viewer. In an alternative embodiment (not shown), the center pixel can have an adjusted direction that is adjusted by adjustment of the angle α. Advantageously, the nominal viewing direction can be adjusted.

[0418] The length I of the main guide facet 176 176 can be arranged to provide an incident light cone 493 T Reflections are reflected from the extraction facet 172 in a lateral direction.

[0419] Fig. 12A It is further illustrated that the pitch p(x) of the extraction facets 172 may vary with distance x from the light retro-reflector 140. In operation, light passing through the polarization-sensitive reflector 700 may be preferentially transmitted at lower distances x, and thus, the extraction efficiency along the extraction waveguide 1 in the direction 193 may decrease with distance x. The pitch p(x) may be arranged to provide improved extraction uniformity in the direction 193 such that the pitch p(x) decreases with distance x. Advantageously, image uniformity may be improved across the exit pupil 40.

[0420] Fig. 12Bis a schematic diagram illustrating a side view of the operation of an array of extraction features 170, each of which includes a prism 171 in which a draft facet 176 is inclined with a surface normal direction n 176 The surface normal direction n of the guide portion 178 of the rear light guide surface 6 178 At an angle δ. Fig. 12B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0421] and Fig. 12A In comparison, Fig. 12B In an alternative embodiment, the angle δ is adjusted so that the light cone 493 T Reflections at the facets 176, 172 are uniformly extracted. Advantageously, vignetting across the image as seen at the user's retina 47 is reduced and image uniformity is improved.

[0422] It may be desirable to reduce glow from the extraction waveguide in the direction of light 461.

[0423] Fig. 12C 1 is a schematic diagram illustrating a side view of the operation of an array of extraction features, each extraction feature including an extraction facet 172 and a draft facet 174 . Fig. 12C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0424] and Fig. 12A In comparison, Fig. 12C In an alternative embodiment, the main guiding facet 176 is omitted from each prism 171, and the reflective material 175 is arranged at least on the extraction facet 172 having a smaller angle α.

[0425] In operation, light ray 460C (193) is reflected by reflection from reflective material 175, rather than by total internal reflection. Advantageously, Fig. 12A The extracted light 461 does not exist, thereby reducing output stray light.

[0426] Fig.12D is a schematic diagram illustrating a side view of the operation of an alternative array of extraction features, each extraction feature comprising an extraction facet 172 and a draft facet 174 , and arranged in groups 173 . Fig.12D Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0427] and Fig. 12C Compared to the embodiment of the present invention, the prisms 171 are arranged in groups 173, wherein the number n(x) of prisms 171 in each group can vary with the distance x from the light retroreflector 140. Further, the pitch p(x) of the groups 173 can vary with the distance x from the light retroreflector 140. Advantageously, the extraction uniformity across the exit pupil 40 can be improved.

[0428] Fig.12E is a schematic diagram illustrating a side view of the operation of an array of extraction features 170 including extraction prisms 171 of varying shapes and sizes. Fig.12E Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0429] and FIG. 12A to FIG. 12D Compared with the implementation scheme, Fig.12E In an alternative embodiment of the present invention, the extraction features 170 include extraction prisms 171A, 171B, 171C of different shapes and sizes, with respective extraction facets 172A, 172B, 172C to reflect light rays 460CA (193) and 460CB (193) to a desired output direction. Some of the prisms 171C can be arranged in groups 173, and the pitch p(x) can be arranged to provide a lateral direction 197 across the exit pupil 40 T Improved uniformity.

[0430] Diffraction of the output image on the retina, uniformity across the exit pupil 40, efficiency, and output stray light can be controlled to advantageously achieve a desired performance tradeoff.

[0431] It may be desirable to reduce stray light output from the extraction waveguide 1 .

[0432] Fig.12F is a schematic diagram illustrating a side view of the operation of an array of extraction features, including a stepped extraction feature 170 . Fig.12F Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0433] exist Fig.12F In an alternative embodiment of FIG. 1 , the extraction feature 170 comprises inclined step facets 12 of the stepped rear guiding surface 6. Intermediate light guiding tread facets 10 are disposed between the steps 12.

[0434] In operation, some of the input light rays 460C (191) may pass through the polarization-sensitive reflector 700 and be incident on the rear light-guiding surface 6. By interacting with, for example, Fig. 12A In comparison, such light is not incident on draft facet 174, and instead is incident on tread portion 10, with step facet 12 being hidden in first direction 191. Stray light for light propagating in first direction 191 is advantageously reduced.

[0435] For light rays propagating in the second direction 193 , some light rays 460C ( 193 ) are reflected by total internal reflection at the tread facets 10 and then the step facets 12 to be output through the front light guiding surface 8 .

[0436] Fig.12F The stepped light guide surface 6 can advantageously be manufactured at low cost. In an alternative embodiment (not shown), Fig.12F The stepped structure can be Fig.12E Advantageously, further optimization improvements can be achieved.

[0437] The structure of the extraction facets 172 arranged to achieve improved image uniformity will now be described.

[0438] Fig.13A is a schematic diagram illustrating a side view of light output 466 from an extraction waveguide 1 including an array of extraction facets 172A- 172B having a draft facet 174 arranged for each extraction facet 172; Fig. 13B is a schematic diagram illustrating a side view of light output from an extraction waveguide 1 including an array of extraction facets 172A-172B having intermediate draft facets 274Aa, 274Ab and intermediate guiding facets 276Aa, 276Ab, 276Ac arranged for extraction facet 172A, and having intermediate draft facets 274Ba, 274Bb and intermediate guiding facets 276Ba, 276Bb, 276Bc arranged for extraction facet 172B; and Fig. 13C is a schematic diagram illustrating a side view of an extraction waveguide 1, which includes an array of extraction facets 172, the extraction facets 172 having intermediate draft facets 274Ba, 274Bb and intermediate guiding facets 276Aa, 276Ab, 276Ac arranged for the extraction facet 172A, and the remaining extraction facets among the extraction facets 172B to 172J include a single draft facet 174A to 174J, respectively. FIG. 13A to FIG. 13CFeatures of the embodiments of the present invention that are not discussed in further detail may be assumed to correspond to features having like reference numerals as discussed above, including any possible variations in the features. The inhomogeneities caused by the arrangement of the prisms 171 will now be described.

[0439] Fig.13A The embodiment diagram illustrates light 460T (193), which is composed of, for example, Figure 1C , and propagates from the light retro-reflector 140 along the extraction waveguide 1 in the second direction 193 .

[0440] At the first prism 171A, a region 273A is created from which no light is directed from the rear guiding surface 6 to the front guiding surface 8, thereby providing missing light in a "hole" region 272Aa at the front guiding surface 8.

[0441] In a similar manner, region 275A of the rear guiding surface 6 is illuminated, and light from region 275A is guided from the rear guiding surface 6 to the front guiding surface 8 to provide a "source" region 271Aa. In this description, the source region is not a physical source, but rather is the active region of the front guiding surface 8 that illuminates the extraction facet 172, and is a result of light propagation through the geometry of the extraction waveguide 1.

[0442] Light rays 460T(193) from source region 271Aa incident on extraction facet 172A are extracted through front guiding surface 8 as ray bundle 466T(44)A. However, "aperture" region 272Aa provides a non-illuminated area from front guiding surface 8 to extraction facet 172A that does not reflect light toward eye 45.

[0443] In a similar manner, aperture regions 272Ba, 272Ca and source region 271Ba are arranged at front guide surface 8. Output ray bundle 466T(44)B is output by reflection of light from source region 271Ba by extraction facet 172A. The brightness of the output from extraction facet 172 will vary with respect to: (i) position along extraction waveguide 1 in direction 193; and (ii) ray angle (representing pixel 222 angular position). Such non-uniformity can provide a pattern in the image that varies with eye position across exit pupil 40.

[0444] It would be desirable to reduce image non-uniformity and to reduce the variation in non-uniformity for eye 45 pupil 44 locations across exit pupil 40 .

[0445] exist Fig. 13BIn an alternative embodiment of the present invention, the prism 171A includes a plurality of draft facets 274Aa, 274Ab, 274Ac and intermediate guide facets 276Aa, 276Ab, and the intermediate guide facets 276Aa, 276Ab are arranged between each adjacent pair of the plurality of draft facets 274Aa, 274Ab, 274Ac. The prism 171B similarly includes a plurality of draft facets 274Ba, 274Bb, 274Bc and intermediate guide facets 276Ba, 276Bb, and the intermediate guide facets 276Ba, 276Bb are arranged between each adjacent pair of the plurality of draft facets 274Ba, 274Bb, 274Bc.

[0446] Through Fig.13A By comparison, such intermediate facets 274 provide an increased number of source regions 271Aa, 271Ab, 271Ac, 271Ba, 271Bb to illuminate respective extraction features such that light beams 466T(44)Aa, 466T(44)Ab are output from extraction feature 172A and light beams 466T(44)Ba, 466T(44)Bb are output from extraction feature 172B. Such an increased number of source regions 271 can advantageously reduce non-uniformity of image output and reduce variations in non-uniformity for movement of eye 45 within exit pupil 40. The number and location of intermediate draft facets 274 and intermediate guiding facets 276 can be modified to achieve desired uniformity characteristics.

[0447] Through Fig. 13B For comparison, Fig. 13C In an alternative embodiment of the present invention, intermediate draft facets 274Aa, 274Ab, 274Ac are provided for the first extraction facet 172A, but not for the subsequent extraction facets 172B to 172J. Such an arrangement preconditions the light propagating along the extraction waveguide 1 in the second direction 193 so that uniformity can be improved. Such an arrangement further reduces the amount of light that would be generated by, for example, Fig. 13B The small source region 271Ca provides a small-sized light beam. The small source region 271Ca provides an output with a small diffraction aperture, and therefore, image blur is increased. Fig. 13C Alternative arrangements may advantageously reduce image blur while achieving desired uniformity. Fig. 13C Further illustrated are chirped extraction facets 172 having a pitch p(x) to further reduce moiré fringe jumps between source regions 271 and respective extraction facets 172 .

[0448] Intermediate draft facets 274 and intermediate guiding facets 276 may be provided with other embodiments of the presently described extraction features 170 to advantageously achieve improved image uniformity. The inner extraction features 170 will now be described.

[0449] Fig.14A is a schematic diagram illustrating a side view of the operation of an array of extraction features including a buried partially reflective stepped extraction feature 170 . Fig.14A Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0450] exist Fig.14A In an alternative embodiment, the extraction element 270 includes an array of extraction reflectors 186 disposed inside the extraction waveguide 1 and arranged between the polarization-sensitive reflector 700 and the rear light guiding surface 6 .

[0451] As illustrated in the enlarged cross-sectional view, the stepped extraction reflector 186 includes extraction surfaces 187A, 187B separated by a partially reflective coating 189. The partially reflective coating 189 may include at least one dielectric layer, such as an adhesive material or other dielectric material. Alternatively, as will be described below, the partially reflective coating 189 may include a stack of dielectric layers, or may be metal-containing, such as aluminum or silver.

[0452] The stepped extraction reflectors 186 extend partially across the extraction waveguide 1 at continuously displaced positions between the relative rear guide surface 6 and front guide surface 8 of the extraction waveguide 1, and the partially reflective layer 184 further includes an intermediate reflector 188 extending along the extraction waveguide 1 between adjacent pairs of stepped extraction reflectors 186.

[0453] In e.g. FIG. 12A to FIG. 12F In an embodiment, the extraction element 270 includes an array of extraction features 170 formed on the rear light guiding surface 6.

[0454] By comparison, in Fig.14A In an alternative embodiment of the invention, the extraction element 270 includes waveguide members 111BA, 111BB separated by a dielectric partially reflective layer 184, which includes a partially reflective stepped extraction reflector 186 and a partially reflective tread facet 188. The dielectric partially reflective layer 184 can be a dielectric stack, the operation principle of which is similar to, for example Fig. 7A The dielectric stack 712 of the dielectric stack can be arranged to achieve a desired reflectivity of the partially reflective layer 184.

[0455] The stepped extraction reflectors 186 are another example of a reflective extraction feature 170, and each stepped extraction reflector 186 includes a set of layers, which are reflective layers described below.

[0456] The extraction waveguide 1 is further arranged to receive the light cone 493 from the lateral deformation component 60 and the lateral deformation component 110 T ; and includes an array of stepped extraction reflectors 186A to 186N arranged inside the extraction waveguide 1.

[0457] The extraction feature 170 includes stepped extraction reflectors 186A to 186N, each of which is inclined at an angle α relative to a first direction 191 and a second direction 193 along an optical axis 199(1) of the extraction waveguide 1. The extraction feature 170 extends partially across the extraction waveguide 1 between the opposing rear guide surface 6 and the front guide surface 8. Fig.14A In the embodiment of the invention, the partially reflective surfaces of the stepped extraction reflectors 186A to 186D extend between the polarization-sensitive reflector 700 and the rear light guiding surface 6. The extraction waveguide 1 includes an intermediate surface 188 extending along the extraction waveguide 1 between adjacent pairs of stepped extraction reflectors 186.

[0458] exist Fig.14A In an alternative embodiment, the partially reflective coating 184 may include a stack 184 of dielectric layers 186A to 186E having alternating high and low refractive indices. Illustrative embodiments are provided in Table 4. A stack 185 of dielectric layers 189A to 189E may be formed on one or both of the waveguide members 111BA, 111BB by, for example, evaporation or sputtering, and the extraction waveguide 1 is assembled by alignment of the waveguide members 111BA, 111BE.

[0459] item Illustrative Materials Refractive Index Thickness(nm) Waveguide member 111BA PMMA 1.50 - Dielectric layer 189A <![CDATA[TiO 2 ]]> 2.6 7 Dielectric layer 189B <![CDATA[SiO 2 ]]> 1.5 79 Dielectric layer 189C <![CDATA[TiO 2 ]]> 2.6 21 Dielectric layer 189D <![CDATA[SiO 2 ]]> 1.5 30 Dielectric layer 189E <![CDATA[TiO 2 ]]> 2.6 45 Waveguide member 111BB PMMA 1.49 -

[0460] Table 4

[0461] The polarization selectivity of the reflection at the partially reflective surface 180 will now be further considered.

[0462] Fig. 14Bis a schematic graph illustrating the variation of reflectivity versus wavelength for light propagating through an extraction reflector including the dielectric layers listed in Table 4. Contour 810 illustrates the total p-polarization state 902 reflectivity for a single reflection from dielectric stack 184, while contour 812 illustrates the total s-polarization state 904 reflectivity for a single reflection from dielectric stack 185, where the thicknesses of Table 2 are arranged to provide approximately 25% reflectivity for each reflection. Adjustment of thickness and / or increasing the number of layers can be used to adjust the reflectivity to achieve a desired reflectivity for s-polarization state 904 light 460C (193).

[0463] In other embodiments (not illustrated), the dielectric stack may include a single layer of material, such as air or an adhesive having a desired refractive index, disposed between members 111BA, 111BB. Advantageously, cost and complexity may be reduced while desired reflectivity and transmission are achieved.

[0464] Considering the material of the waveguide members 111A, 111B in this embodiment and other embodiments described elsewhere herein, materials with higher refractive indices (such as polycarbonate or high refractive index glass) may be used. Advantageously, the increased field of view φ T May be provided in landscape orientation.

[0465] In operation, some light rays 465 (193) are transmitted through the partially reflective stepped extraction reflector 186 and the partially reflective tread facets 188 and are directed between the rear guide surface 6 and the front guide surface 8. Some light passed by the polarization-sensitive reflector 700 is transmitted along the extraction waveguide 1 and is not extracted near the light retro-reflector 140. Other light rays 467 (193) are reflected by the partially reflective tread facets 188 and are not extracted near the light retro-reflector 140. Advantageously, improved uniformity can be achieved across the exit pupil 40.

[0466] Further, each of the stepped extraction reflectors 186 may see light in a lateral direction from the entire light retroreflector 140. Vignetting across the field of view may be reduced, and uniformity in the output image seen on the retina 47 may be advantageously improved.

[0467] It may be desirable to increase the size of the extraction feature 170 .

[0468] Fig.15 is a schematic diagram illustrating a side view of operation, wherein an array of extraction features 170 includes an inclined partially reflective surface 180; and Fig.16 is a diagram illustrating a partially reflective surface 180 along Fig.15 Schematic diagram of a variation of the extraction waveguide 1. Figure 15 to Figure 16Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0469] exist Fig.15 and Fig.16 In an alternative embodiment of the extraction waveguide 1, the extraction waveguide 1 includes an array of extraction features 170, the extraction features 170 including a partially reflective surface 180 disposed inside the extraction waveguide 1, the partially reflective surface 180 being arranged to transmit light 400 guided along the extraction waveguide 1 in a first direction 191 and to extract light guided along the extraction waveguide 1 in a second direction 193 towards an eye 45 of a viewer disposed in the exit pupil 40. The array of extraction features 170 is distributed along the extraction waveguide 1 so as to provide an expansion of the exit pupil 40 in a lateral direction 197.

[0470] Partially reflective surface 180 is another example of a reflective extraction feature 170, and each partially reflective surface includes a set of layers that are Fig.14A Reflective layers similar to those illustrated in Table 4.

[0471] The extraction waveguide 1 is further arranged to receive the light cone 493 from the lateral deformation component 60 and the lateral deformation component 110 T .

[0472] The extraction features 170, including the partially reflective surfaces 180A to 180D, are each inclined at an angle α relative to a first direction 191 and a second direction 193 along an optical axis 199(1) of the extraction waveguide 1. The extraction features 170 extend partially across the extraction waveguide 1 between the opposing rear guide surface 6 and front guide surface 8. Fig.15 In an embodiment of the present invention, the partially reflective surfaces 180A to 180D extend between the polarization-sensitive reflector 700 and the rear light guiding surface 6.

[0473] The dielectric stack of partially reflective surface 180 may be formed on one or both surfaces of adjacent plates 181. In other embodiments, the dielectric stack may be replaced with a single dielectric layer, metal, or gap.

[0474] The partially reflective surfaces 180A to 180D are arranged to cause a light cone 491 to be guided along the extraction waveguide 1 in a first direction 191. T At least some of the light 468 is transmitted, and at least some of the light cone 493 that is guided back along the extraction waveguide 1 in the second direction 193 is extracted toward the eye 45 of a viewer 47 arranged in the exit pupil 40.

[0475] The partially reflective surface 180 includes a dielectric stack including dielectric layers that may vary between different partially reflective surfaces 180A- 180D.

[0476] Fig.16 is a diagram illustrating that, in the case where the extraction waveguide includes four partially reflective surfaces 180A-180D, the reflectivity of the partially reflective surface 180 is along Fig.15 Schematic diagram of the extraction waveguide 1 in a first direction 191 and with variations of the illustrative embodiment of Table 5. Fig.16 Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0477]

[0478] Table 5

[0479] exist Fig.16 In an alternative embodiment of the invention, the partially reflective surfaces 180 extend across the extraction waveguide 1 and have the same reflective area. The reflectivity of the partially reflective surfaces 180 is defined across their entire area and increases with increasing distance along the optical axis 199(1) (that is, along the extraction waveguide 1 along the second direction 193) for light reflected from the light retro-reflector 140. In other words, the reflectivity of the partially reflective surfaces 180 is defined across their entire area and increases with increasing distance along the extraction waveguide 1 in the direction 193 from the light retro-reflector 140.

[0480] The stack reflectivity profile of Table 5 achieves uniform output power δ for light rays 469A-469D so that, advantageously, uniform image brightness is seen for different pupil 44 locations across exit pupil 40. Such a reflectivity profile can be achieved by adjusting the dielectric stack to be different at each partially reflective surface 180. Such differences can be achieved by adjusting the number, thickness, and material of dielectric layers 186.

[0481] An illustrative embodiment of Table 5 is Fig.15 and Fig.16 The partially reflective surface 180 is substantially transparent to light 460C having the p-polarization state 902 because the partially reflective surface 180 is substantially transparent to the light 460C having the p-polarization state 902. Thus, the reflector 180D is substantially blocking to the transmitted s-polarization state 904, but is transmissive to the p-polarization state 902 and is therefore, in a general sense, partially transmissive.

[0482] and Fig.12E , Fig.12F or Fig.14AThe width w of the extraction feature 170 including the partially reflective surface 180 along the extraction waveguide 1 in the direction 193 is increased compared to the arrangement of FIG. Advantageously, diffraction from the aperture of the partially reflective surface 180 is reduced and image fidelity is improved.

[0483] Alternative arrangements of the reflective extraction element 270 will now be described.

[0484] Fig.17A is illustrated in a perspective front view Fig.17A Schematic diagram of an alternative arrangement of a deformed near-eye display device 100 in which some of the partially reflective surfaces 180 do not extend the entire thickness of the extraction waveguide 1 between the polarization-sensitive reflector 700 and the rear light guiding surface 6; and Fig. 17B is illustrated in side view Fig.17A Schematic diagram of the operation of a deformed near-eye display device 100. FIG. 17A to FIG. 17B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0485] exist FIG. 17A to FIG. 17B In an alternative embodiment of the reflective extraction feature 170 is a partially reflective surface 180 extending across a portion of the extraction waveguide 1, the array of partially reflective surfaces 180 having a reflectivity defined across their entire area that increases with increasing distance along the optical axis 199 in the direction 193 along the extraction waveguide 1. In other words, the partially reflective surfaces 180 are patterned to have different reflective areas that provide a reflectivity defined across their entire area that increases with increasing distance along the optical axis 199 (60) in the second direction 193. In the region 183 of the interface between the plates 181, it is arranged to be transmissive. Alternatively or in addition, the partially reflective surfaces 180 can be patterned to have different reflective areas that provide a reflectivity defined across their entire area that increases with increasing distance along the optical axis 199 (60) in the second direction 193.

[0486] Such a partially reflective surface 180 can be manufactured by masking the plate 180 during the formation of the dielectric layers 186A to 186N (e.g., by deposition). Some areas 181 of the plate's surface may therefore be free of dielectric stacks. As illustrated in Table 4, the total focal power δ extracted at each facet may be constant across the array of partially reflective surfaces 180A to 180D. Fig.18B In contrast, the dielectric stack composition may be the same for each of the partially reflective surfaces 180A to 180D. Advantageously, the deposition cost and complexity of deposition onto the plate 180 may be reduced.

[0487] Fig.18Ais illustrated in a perspective front view Fig.17A A schematic diagram of an alternative arrangement of a deformed near-eye display device 100 in which the partially reflective surface 180 includes a patterned reflector 187; and Fig.18B is illustrated in side view Fig.18A Schematic diagram of the operation of a deformed near-eye display device 100. FIG. 18A to FIG. 18B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0488] exist FIG. 18A to FIG. 18B In an alternative embodiment, for example as illustrated in Table 4, the partially reflective surface 180 has a density of patterned areas of reflectors 187 separated by transmissive regions 183 that increases with distance along the extraction waveguide 1 in direction 193 away from the light retroreflector 140 to achieve a desired reflectivity profile.

[0489] Patterning of the partially reflective surface 180 may enable reduced manufacturing complexity of the plate 180 .

[0490] Further, the partially reflective surface 180 can include a patterned reflector 187 that includes a high reflectivity metal compared to the dielectric stacks discussed elsewhere herein. Advantageously, the manufacturing cost of the partially reflective surface 180 can be reduced.

[0491] Fig.19A is a schematic diagram illustrating, in side view, an arrangement of an extraction waveguide 1 comprising an alternative array of extraction features 270; and Fig.19B is a schematic graph illustrating the variation of reflectivity with incident angle for polarized light from a dichroic stack. FIG. 19A to FIG. 19B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0492] exist Fig.19A In an alternative embodiment of the invention, the polarization-sensitive reflector 700 includes a dichroic stack 712, and the extraction element 270 includes an array of tilted dichroic stacks 389. The dichroic stack 389 is an example of a partially reflective coating 189 as described elsewhere above, and is provided in a zigzag arrangement with dichroic stack facets 289A, 289B. The dichroic stack 389 is provided by alternating layers of high and low refractive index materials, such as dichroic materials used in the manufacture of polarizing beam splitters similar to those illustrated in Table 2 above.

[0493] The light extraction element 270 may be formed by depositing the dielectric layer 174 of the dichroic stack 389 onto the prism array 286. After depositing the dichroic stack 389, a planarization layer 288 may be provided and further, a front guiding surface 8 is provided.

[0494] Fig.19B Illustration of SiO 2 and TiO 2 2, 389. FIG. 2 shows an example of Fresnel reflectivity 903, 905 for s-polarized light polarization state 902 and p-polarized light polarization state 904, respectively, at a single interface between . At the Brewster angle, the reflectivity of p-polarized light polarization state 904 is close to zero, and so the light is transmitted by the dichroic stack 389, and the s-polarized light polarization state 902 is at least partially reflected. By comparison, for coaxial incidence (such as coaxial incidence at the dichroic stack 712), the light is transmitted for both polarization states 902, 904. In practice, for the dichroic stacks 712, 389, a multilayer stack (such as the illustrative multilayer arrangement of Table 2) can be provided.

[0495] consider Fig.19A In operation, light ray 460C (193) having p-polarized light polarization state 904 is returned from light retroreflector 140 and polarization conversion retarder 72. Light ray 460C (193) is transmitted from waveguide member 111A through dichroic stack 712 of polarization-sensitive reflector 700.

[0496] Light 460C (193) is converted from linear p-polarization state 904 to linear s-polarization state 902 by polarization conversion retarder 73. Polarization conversion retarder 73 may include a half-wave plate for a design wavelength (e.g., 550 nm) and may include a Pancharatnam stack of retarders to achieve improved spectral uniformity. Optical axis direction 773 may be arranged to provide a rotation of linear polarization state 904 to linear polarization state 902 at the design wavelength.

[0497] Light 460C (193) from polarization conversion retarder 73 is incident on dichroic stack facet 289A at near normal incidence and is transmitted. Light is directed from rear guiding surface 6 and at dichroic stack facet 289B at an incident angle β close to the Brewster angle, which in the illustrative example is 60 degrees, and some of the light having polarization state 902 is transmitted as light 463C. R (193) is reflected toward the user's eyes 45.

[0498] The dichroic stack 712, 389 may be conveniently provided by dichroic material deposition at low cost.The dichroic stack 712, 389 may be provided by the same coating stack design to achieve the desired light propagation properties, thereby advantageously providing reduced manufacturing costs.

[0499] The dimensions f of the facets 289A, 289B may be arranged to minimize diffraction blur in the image seen by the user. Advantageously, improved fidelity of image quality may be achieved.

[0500] Fig.19C is a schematic diagram illustrating, in side view, an arrangement of an extraction waveguide including an alternative array of extraction features 270; and Fig.19D is a schematic diagram illustrating an arrangement of an extraction waveguide including an alternative array of extraction features 270 in side view. FIG. 19C to FIG. 19D Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0501] Through Fig.19A For comparison, Fig.19C Alternative embodiments illustrate that facet 289B may not be provided with a dichroic stack. Such an arrangement can be achieved by dichroic stacking being deposited obliquely onto facet 289A, thereby minimizing the coating on facet 289B. In operation, light 460C (193) is transmitted at the site of facet 289B and is reflected by facet 289A. Advantageously, efficiency is improved, and stray light is reduced, thereby achieving reduced glare.

[0502] Through Fig.19A For comparison, Fig.19D An alternative embodiment includes additional planar facets 289C in the dichroic layer 389 to achieve some guiding of light from the front guiding surface 8. Advantageously, image uniformity may be improved.

[0503] The extraction features 170 comprising the diffractive structures will now be described.

[0504] Fig. 20A is a schematic diagram illustrating a side view of the operation of an array of extraction features 170 including a surface relief grating 280 . Fig. 20A Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0505] exist Fig. 20AIn an alternative embodiment, the rear guiding surface 6 includes a surface relief grating 280, which includes extraction features 170 provided by the surface structure of the surface relief grating. The pitch Δ of the surface relief grating 280 is arranged to provide incident light reflected through the front light guiding surface 8 to reach the exit pupil 40.

[0506] and Fig.12E Compared with the prismatic structure 171 including the reflective facet 172, Fig. 20A Embodiments of provide reduced blurring due to diffraction from the large aperture width w of the reflective extraction features 170. Advantageously, image resolution may be improved.

[0507] Fig. 20B is a schematic diagram of a side view illustrating the operation of an array of extraction features 170 including a volume diffractive optical element 282. Fig. 20B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0508] and Fig. 20A Compared with the implementation scheme, Fig. 20B In an alternative embodiment, the volume diffraction optical element 282 may include a diffraction structure including a modulated phase grating (which includes an array of reflective extraction features) disposed within the extraction waveguide 1, such that the volume diffraction optical element 282 is arranged to provide incident light reflection through the front light guiding surface 8 to reach the exit pupil 40.

[0509] Fig. 20B The extraction waveguide 1 may be formed by forming a polarization-sensitive reflector 700 on the rear surface of the waveguide member 111 and forming a volume diffractive optical element 282 on the polarization-sensitive reflector 700. Advantageously, the thickness may be reduced.

[0510] and Fig.12E Compared with the prismatic structure 171 including the reflective facet 172, Fig. 20B Embodiments of provide reduced blurring due to diffraction from the large aperture width w of the reflective extraction features 170. Advantageously, image resolution may be improved.

[0511] The spectral bandwidth of the reflection can be increased by providing chirp or multiple volume diffractive optical elements 282.

[0512] Fig. 20C is a schematic diagram illustrating a side view of the operation of an array of extraction features 170 including different types of extraction features. Fig. 20CFeatures of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0513] exist Fig. 20C In an alternative embodiment, in a first direction 191, light 460C (191) is guided between the polarization-sensitive reflector 700 and the front light guiding surface 8. In a second direction 193, at least some of the light 460C (193) is transmitted through the polarization-sensitive reflector 700 and is incident on an extraction element 270, which includes a rear guiding surface 6 and an array of extraction features 170, the extraction features 170 including reflective facets 172, diffractive optical elements 282, partially reflective surfaces 180, and stepped extraction reflectors 186 for extracting light through the front light guiding surface 8 to reach the exit pupil 40.

[0514] In alternative embodiments, other combinations of extracted features may be used. For example Fig. 20C The embodiments illustrate different types of extraction features that achieve improved image resolution, efficiency, and uniformity for the user's eye 45.

[0515] like Figure 3C As illustrated in , some light may return to input 2. It would be desirable to minimize crosstalk and improve the contrast of the anamorphic near-eye display device 100.

[0516] Fig.21A is a schematic diagram illustrating a side view of optical isolation near input 2 of a deformed near-eye display device 100 including an emissive spatial light modulator 48; and Fig.21B It is illustrated by Fig.21A Schematic diagram of the optical axis alignment direction of the polarization control assembly. FIG. 21A to FIG. 21B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0517] exist FIG. 21A to FIG. 21B In an alternative embodiment, the optical system 250 further includes: an input linear polarizer 70, which is arranged between the transverse optical component 60 and the input end 2 of the extraction waveguide 1; and a polarization conversion retarder 71 having an orientation of an optical axis 871, which is arranged between the transverse optical component 60 and the input linear polarizer 70, and the polarization conversion retarder 71 is arranged to convert the polarization state of light passing through the polarization conversion retarder 71 between linear polarization states 934, 939 and circular polarization states 936, 938, respectively.

[0518] In other words, the input linear polarizer 70 is disposed behind the lateral deformation component 60, and the optical system 250 further includes a polarization conversion retarder 71 disposed between the lateral deformation component 60 and the input linear polarizer 70, and the polarization conversion retarder 71 is arranged to convert the polarization state of light passing through the polarization conversion retarder 71 between a linear polarization state and a circular polarization state.

[0519] The polarization conversion retarder 71 has a retardation of a quarter wavelength at a visible wavelength (e.g., 550 nm) and can be, for example, a Pancharatnam stack of retarders. The retardation of the polarization conversion retarder 71 can be different from a quarter wavelength, but is selected to provide the same effect. For example, the polarization conversion retarder 71 can have a retardation of, for example, three quarters of a wavelength or five quarters of a wavelength.

[0520] In operation, light 401 from spatial light modulator 48 is output in an unpolarized light state 930 and then polarized by input linear polarizer 70 to provide linear polarization state 902 in extraction waveguide 1. Some light 35 may return toward input end 2 and be transmitted through input linear polarizer 70 as described elsewhere herein.

[0521] The light 35 returning toward the input end 2 along the extraction waveguide 1 in the second direction 193 may have been partially depolarized within the extraction waveguide 1 and has an incident polarization state 932, which can be considered as a superposition of the polarization state of p-polarization and the polarization state of s-polarization. The linear polarization state 934 (which is p-polarized) is transmitted by the input linear polarizer 70, while the orthogonal (s-polarized) polarization state is absorbed. The light 35 with the p-polarization state 934 is converted to a circular polarization state 936 by the polarization conversion retarder 71 and is incident on the surface of the transverse lens 61 and the spatial light modulator 48. The Fresnel reflection of the light 35F at the surface is reflected back toward the additional polarization conversion retarder 71 with a π phase shift so that the orthogonal polarization state 938 is reflected. The polarization conversion retarder 71 provides a polarization state 939 of s-polarization that is absorbed by the input linear polarizer 70. Back reflections from the spatial light modulator 48 and the transverse lens 61 are advantageously reduced. The additional polarization converting retarder 71 thus provides optical isolation of such return light rays 35, so that light rays 35F reflected back from the surface of the transverse lens 61 into the extraction waveguide 1 are reduced. Advantageously, image contrast is improved.

[0522] An input linear polariser 70 and an additional polarisation converting retarder 71 may be incorporated into the input 2. Advantageously, an improved reduction of reflections from the input may be achieved.

[0523] Fig. 21Cis a schematic diagram illustrating a side view of optical isolation for a deformed near-eye display device 100 including a transmissive or reflective spatial light modulator 48; and Fig.21D It is a diagram showing the Fig. 21C Schematic diagram of the optical axis alignment direction of the polarization control assembly. FIG. 21C to FIG. 21D Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0524] and Fig.21A In comparison, Fig. 21C In an alternative embodiment of the spatial light modulator 48, the output linear polarizer 70S and a further polarization conversion retarder 71S having an optical axis direction 871S are provided. In operation, the input linear polarizer 70 and the polarization conversion retarder 71S are provided as for Fig.21A The output linear polarizer 70S provides a linear polarization state 941 which is transmitted through a further polarization conversion retarder 71S to provide a circular polarization state 943. The polarization state 943 is converted back to a linear polarization state 902 by the polarization conversion retarder 71S and transmitted through the input linear polarizer 70. Advantageously, brightness and contrast can be improved in a spatial light modulator 48 that includes a polarized output, such as an LCD and LCOS.

[0525] Further illustrative arrangements of the extraction features 170 will now be described. In the embodiments below, the most typical extraction features 170 are illustrated as extraction facets 172. However, other types of extraction features, such as step facets 12, partially reflective stepped extraction reflectors 186, partially reflective surfaces 180, surface relief gratings 280, or volume diffractive optical elements 282 may be provided in addition or alternatively. Similarly, the polarization-sensitive reflector 700 may be provided as described elsewhere herein.

[0526] Fig.22A is a schematic graph of the profile of the rear guide surface 6 as a function of distance x along the extraction waveguide 1 in the direction 191 for various illustrative arrangements of the extraction features 170; Fig. 22B is a schematic graph of facet width w as a function of position along the extraction waveguide 1 for various illustrative arrangements of steps for a stepped surface; and Fig. 22C is a schematic diagram illustrating an arrangement of a chirp extraction feature 170 for a monocular near-eye anamorphic display device 100 in front view. FIG. 22A to FIG. 22C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0527] Fig.22A The profile 370 illustrates the rear guide surface 6, as Fig. 22B As illustrated by the profile 371 in FIG. 1 , the rear guiding surface 6 includes 60 degree tilted extraction features 170 arranged at a uniform 1 mm pitch, with a step height h of approximately 0.49 mm and a uniform step range w of 0.28 mm. The step range w provides a diffraction aperture for the light 401 directed toward the pupil 44 of the eye, so diffraction blur is added to the image data in the lateral direction 197. It would be desirable to increase the range w, thereby reducing the diffraction blur in the lateral direction, so that Figure 1F The blur ellipse height 454 in the lateral direction 197 is minimized.

[0528] Fig.22A The outline of 372 Fig. 22B and Fig. 22C The profile 373 illustrates an alternative embodiment in which the extraction features 170 have a varying spacing s along the extraction waveguide 1 in the direction 191. Further, the extraction features 170 have a varying range w along the extraction waveguide 1 in the direction 191. Thus, considering the center extraction feature 170C, the range w is 0.5 mm, while the top extraction feature 170T has a range of 0.15 mm. Diffraction blur is reduced for light from the center of the extraction waveguide 1, which can be the preferred viewing location for the pupil 44. Thus, high image quality can be achieved for the preferred viewing location, while off-axis images from the top extraction feature 170T and the bottom extraction feature 170B are degraded. The best image quality is provided in the preferred viewing direction, advantageously achieving high image performance for the most commonly used image data.

[0529] Fig.22A 7D . The range w is increased for each step while maintaining a constant 1 mm spacing. Advantageously, diffraction blur is reduced compared to the embodiment of profile 370. Further, for a given range w, the overall thickness t of the extraction waveguide 1 can be advantageously reduced while achieving a desired spacing p such that multiple extraction features 170 overlap the pupil 44.

[0530] It would be desirable to further reduce the occurrence of image blur due to diffraction in the lateral direction 197 from the range w of the extraction features 170 .

[0531] Fig.22D is a schematic diagram illustrating, in front view, an arrangement of a chirp extraction feature 170 for a binocular near-eye anamorphic display device 1 . Fig.22DFeatures of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0532] exist Fig.22D In an alternative embodiment, extraction features 170RA to 170RN for pupil 44R of right eye 45R have a first profile of pitch s and extent w along extraction waveguide 1 in direction 191. Further, extraction features 170LA to 170LN have a second profile of pitch s and extent w different from the first profile.

[0533] exist Fig.22D In an illustrative embodiment of the invention, the top extraction features 170RT for directing light toward the right pupil 44R have a large spacing, so the diffraction blur is low, while the bottom extraction features 170RB for directing light toward the right pupil 44R have a small spacing, so the diffraction blur is increased. Further, the top extraction features 170LT for directing light toward the left pupil 44L have a small spacing, so the diffraction blur is higher, while the bottom extraction features 170LB for directing light toward the left pupil 44L have a larger spacing, so the diffraction blur is reduced. In operation, the human visual system can combine two different blurs for the left eye image and the right eye image. Such a combination can achieve an improved perceived blur compared to an arrangement in which the first profile and the second profile have the same spacing s and range w. Advantageously, improved image quality can be perceived.

[0534] A headgear 600 including the deformed near-eye display device 100 will now be described.

[0535] Fig.23A is a schematic diagram illustrating an augmented reality head mounted display device 600 in a perspective front view, the augmented reality head mounted display device 600 comprising a monocular anamorphic display device having a spatial light modulator 48 and a lateral anamorphic component 60 arranged at an eyebrow position, the lateral anamorphic component 60 being formed by a lateral lens 61; and Fig. 23B is a schematic diagram illustrating an augmented reality head mounted display device 600 in a perspective front view, the augmented reality head mounted display device 600 comprising binocular deformable display devices 100L, 100R having spatial light modulators 48R, 48L and lateral deformable components 60R, 60L arranged at eyebrow locations. FIG. 23A to FIG. 23B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0536] FIG. 23A to FIG. 23BThe head-mounted display devices 600 each include at least one deformable near-eye display device 100 and a head fixing arrangement 602 arranged to fix the deformable near-eye display device 100 on the wearer's head, wherein the deformable near-eye display device 100 extends across at least one eye 45 of the wearer.

[0537] The head mounted display device 600 may include a pair of glasses including a deformed near-eye display device 100 described elsewhere herein, the deformed near-eye display device 100 being arranged to extend across at least one eye 45 of a viewer 47 when the head mounted display device 600 is worn. The head mounted display device 600 may include a pair of glasses including a glasses frame having a head fixed arrangement 602, the head fixed arrangement 602 including a frame 603 and an arm 604. In general, any other head fixed arrangement may be provided alternatively. The frame 602 and / or the arm 604 may include an electrical system for power supply, sensing and control of at least the lighting system 240. The deformed near-eye display device 100 of the embodiment of the present application may be provided with a light weight and may be transparent. The head mounted display device 600 may be tied to a remote control system by a wire, or may not be tied for wireless control. Advantageously, comfortable viewing of augmented reality content, mixed reality content, or virtual reality content may be provided.

[0538] It may be desirable to provide an aesthetically pleasing appearance for the anamorphic near-eye display device 100 .

[0539] Fig.23C is a schematic diagram illustrating an eyepiece arrangement 102 for an augmented reality head mounted display device 600 including an embedded display device 100 in a perspective front view. Fig.23C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0540] The eyepiece arrangement 102 may be arranged within the head mounted display device 600 and may include a deformable near eye display device 100. The extraction waveguide 1 may be embedded with a substrate 103 that extends around the components 111A, 110 of the deformable near eye display device 100. The shape of the substrate 103 may be contoured to fit various shaped head mounted display devices, such as glasses. Advantageously, the aesthetic appearance may be improved.

[0541] The edge 105 of the substrate 103 may be provided with a light absorbing surface that absorbs incident light from the deformable near-eye display device 100. The light absorbing surface may be a structured anti-reflective surface coated with an absorbing material. Advantageously, image contrast may be improved.

[0542] It may be desirable to change the positioning of lighting system 240 in head mounted display device 600 .

[0543] The eyepiece arrangement 102 including the substrate 103 may further be provided to other embodiments among the embodiments of the present disclosure.

[0544] Fig.24A is a schematic diagram illustrating a deformed near-eye display device 100 having a spatial light modulator 48 at the temple site in a perspective front view; Fig. 24B is a schematic diagram illustrating an augmented reality head mounted display device 600 in a perspective front view, the augmented reality head mounted display device 600 including a left eye anamorphic display device having a spatial light modulator disposed at a temple position; and Fig.24C is a schematic diagram illustrating an augmented reality head mounted display device 600 in a perspective front view, the augmented reality head mounted display device 600 including a left eye anamorphic display device and a right eye anamorphic display device with spatial light modulators arranged at the temple positions. FIG. 24A to FIG. 24C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0545] and Figure 1A Compared to the arrangement of , the illumination system 240 is arranged to the side of the extraction waveguide 1 and in the direction 191, in which the extraction waveguide 1 extends in a horizontal direction to the user's eye 45. Therefore, the lateral direction 195 to the pupil 44 is vertical and the lateral direction 197 is horizontal. The deformable near-eye display device 100 can be arranged in the arm of the head mounted component 600, reducing the volume of the frame of the head mounted display device. Advantageously, the aesthetic appearance of the head mounted display device can be improved. Further, the connection between the illumination system 240 and the control electronics arranged in the arm 604 can be provided with reduced complexity, thereby reducing costs.

[0546] It would be desirable to provide a virtual reality head mounted display device 600 in which the head mounted display device is not transparent to external images.

[0547] Fig.25A is a schematic diagram illustrating a virtual reality head mounted display device 600 including a left eye deformable display device 100R and a right eye deformable display device 100L in a front view; and Fig.25B is a schematic diagram illustrating a virtual reality head mounted display device 600 including a deformable near-eye display device 100 in a side view. FIG. 25A to FIG. 25BFeatures of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0548] Fig.25A An alternative embodiment of the head mounted display device 600 may include display devices 100R, 100L, the size of the display devices 100R, 100L is greater than Fig. 23B The desired size of the glasses head mounted display device 600. Figure 1F , aberrations can be reduced for a given field angle, and the field of view can be increased for a given elliptical blur 452 limit. Further, image brightness can be improved.

[0549] Fig.25B The diagram illustrates an alternative arrangement in which a light trap layer 609 is provided between the head mounted display device 600 housing 606 and the extraction waveguide 1 to receive stray light 607 output from the extraction waveguide 1. Advantageously, image contrast is improved.

[0550] It may be desirable to reduce the number of illumination systems in a binocular near-eye display.

[0551] Fig.25C is a schematic diagram illustrating, in front view, a deformed near-eye display device 100 comprising a single waveguide 1 suitable for use with both eyes of a display user. Fig.25C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0552] The array of extraction features 170 comprises two separate regions 177L, 177R, each region 177L, 177R being arranged to extract light guided along the extraction waveguide 1 towards a respective eye 45L, 45R of a viewer 47. Non-extraction regions 179A to 179C are arranged in the extraction waveguide 1 outside the separate regions 177L, 177R.

[0553] Thus, a single illumination system 240 including a spatial light modulator 48 may be arranged to provide illumination to both eyes 45R, 45L. Advantageously, cost and complexity are reduced.

[0554] It may be desirable to improve the performance and functionality of head mounted display device 600.

[0555] Fig.25D is a schematic diagram illustrating, in side view, a head mounted display device including two deformed near-eye display devices; and Fig.25E It is illustrated by Fig.25DSchematic diagram of a composite image provided to eye 45 by head-mounted display device 600. FIG. 25D to FIG. 25E Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0556] exist Fig.25D In an alternative embodiment, the deformed near-eye display device 100A is a first near-eye display device, and the head-mounted display device 600 further includes a second near-eye display device 100B, wherein the second near-eye display device 100B is arranged in series with the first near-eye display device 100A and is arranged to receive light from the first near-eye display device 100A.

[0557] The near-eye anamorphic display device 100A includes a spatial light modulator 48A having a first size and density of pixels 222; a laterally anamorphic component 60A having a first lateral optical power; and an extraction waveguide 1A, which includes a laterally anamorphic component 110A having a first lateral optical power. The near-eye anamorphic display device 100B includes a spatial light modulator 48B, which may have the same or different size and density of pixels 222 as the spatial light modulator 48A; a laterally anamorphic component 60B having a second lateral optical power, which may be the same or different from the first lateral optical power; and an extraction waveguide 1A, which includes a laterally anamorphic component 110A having a second lateral optical power, which may be the same or different from the first lateral optical power.

[0558] The spatial light modulators 48A, 48B, the lateral deformation components 60A, 60B, the side deformation components 110A, 110B, and the extraction features 170 can be arranged to provide desired improved optical performance, including at least one of the following: (i) improved image resolution; (ii) improved brightness; (iii) increased exit pupil 40 size; (iv) reduced image diffraction; (v) increased field of view; and (vi) multiple focal planes.

[0559] exist Fig.25D In the illustrative embodiment of , the spatial light modulators 48A, 48B are identical, but the lateral anamorphic components 60A, 60B and the side anamorphic components 110A, 110B are different so that the magnification provided by the respective anamorphic display devices 100A, 100B is different. Fig.25EThe diagram illustrates that an outer image region 448A having a boundary 449A is provided by the anamorphic near-eye display device 100A, and a central image region 448B having a boundary 449B is provided by the anamorphic near-eye display device 100B. Advantageously, a high-resolution image can be provided in the central region 448A, overlaid on a lower-resolution image in the outer region 448B. Such an arrangement can advantageously achieve improved image fidelity for the most common viewing directions while providing a large field of view.

[0560] Fig.25D It is also illustrated that the extraction features 170 may be provided with different alignments to achieve increased exit pupil 40 size and reduce diffraction blur.

[0561] It may be desirable to improve the performance of virtual reality display systems.

[0562] Fig.26A is a schematic diagram illustrating in side view a virtual reality head mounted display device 600 including a deformed near eye display device 100 arranged to receive light from a magnifying lens 610; and Fig.26B is a schematic diagram illustrating, in side view, a virtual reality head mounted display device including an anamorphic near eye display device disposed between an anamorphic spatial light modulator and a magnifying lens of a non-anamorphic display device. FIG. 26A to FIG. 26B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0563] exist Fig.26A In an alternative embodiment, the head-mounted display device 600 further includes a non-deformation near-eye display device 610, wherein the non-deformation near-eye display device 610 includes a non-deformation spatial light modulator 648 and a non-deformation magnification optical system, such as a lens 660; and wherein at least one near-eye display device 100 is arranged in series with the non-deformation near-eye display device 610 and is arranged to receive light from the non-deformation near-eye display device 610.

[0564] Fig.26A 6 is an example of a head mounted display device 600 including a lens 660 having optical power, with the anamorphic near-eye display device 100 covering the lens 660. The lens 660 may include a refractive lens, or may be catadioptric, such as a pancake lens.

[0565] exist Fig.26BIn an alternative embodiment of the present invention, the deformable near eye display device 100 can be arranged in series with the non-deformed spatial light modulator 648, arranged between the non-deformed spatial light modulator 648 and the non-deformed near eye display device 610. The deformable near eye display device can be arranged substantially at the pupil of the magnification optical system 660 to provide no optical power to the light from the non-deformed near eye display device 100. Alternatively, some small optical power for the light from the deformable near eye display device 100 can be provided to modify the virtual image distance. The overall thickness of the optical system can be reduced, advantageously achieving a reduced volume.

[0566] exist FIG. 26A to FIG. 26B In an embodiment of the present invention, non-anamorphic magnification optical system 660 may include a lens, such as a Fresnel lens, a pancake lens, or other known non-anamorphic magnification lens, and is arranged to provide a virtual image of the spatial light modulator 648 to the eye 45. Compared to the anamorphic near-eye display device 100, the non-anamorphic near-eye display device 610 provides equal magnification of the pixels 622 on the non-anamorphic spatial light modulator 648 in the lateral direction 195 and the transverse direction 197. The non-anamorphic magnification optical system 660 is generally circularly symmetric.

[0567] In operation, the top pixel 620T of the non-deformed spatial light modulator 648 provides light 662T, the center pixel 620C provides light 662C, and the bottom pixel 620B provides light 662B. The viewer's eye 45 collects the light 460T, 460C, 460B and generates an image on the retina of the eye so that the image is perceived at an angular size that is magnified compared to the angular size of the spatial light modulator 48.

[0568] The spatial light modulator 48, 648, the non-anamorphic magnification optical system 660, the lateral anamorphic component 60; the lateral anamorphic component 110 and the extraction features 170 can be arranged to provide desired improved optical performance, including at least one of the following: (i) improved image resolution; (ii) improved brightness; (iii) increased exit pupil 40 size; (iv) reduced image diffraction; (v) increased field of view; and (vi) multiple focal planes.

[0569] Fig.27A is a schematic diagram illustrating, in side view, an arrangement of a virtual image distance for a virtual reality display device. Fig.27A Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0570] consider Fig.26AIn an embodiment, the virtual image distance 61 from the eye 44 to the virtual image 34 provided by the deformable near-eye display device 100 can be at a distance 663 from the infinite conjugate plane 33, and by controlling the back working distance F of the spatial light modulator 648 to the non-deformation magnification system 660, the virtual image 634 provided by the non-deformation near-eye display device 610 can be at a distance 661 from the infinite conjugate plane 633.

[0571] More generally, the virtual image distance for light from the first near eye display device 100A, 100 may be different than the virtual image distance for light from the second near eye display device 100B or the non-deformed near eye display device 610, respectively.

[0572] Advantageously, the comfort of using the display can be improved.

[0573] FIG. 27B to FIG. 27C This diagram is for Fig.27A Schematic diagram of an arrangement of displayed virtual images. FIG. 27B to FIG. 27C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0574] Fig.27B The diagram illustrates an image 448A having a boundary 449A provided by the deformed near-eye display device 100. Fig.27C The diagram illustrates an image 448B provided by a non-deformed near-eye display device 610 having a boundary 449B.

[0575] Background image 448A and foreground image 448B are provided such that image 448A may further include an occlusion image 77 which, in operation, is aligned with foreground image 448B, which overlays the background image.An opaque foreground image may advantageously be implemented.

[0576] An alternative arrangement of the laterally anamorphic assembly 110 including a Pancharatnam-Berry lens will now be described.

[0577] Fig.28A is a schematic diagram illustrating, in front view, a deformed near-eye display device 100 including a reflective end 4 including a Pancharatnam-Berry lens 350 . Fig.28A Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0578] exist Fig.28AIn an alternative embodiment of the deformable near-eye display device 100, the lens 95 of the lateral deformable component 110 is a Pancharatnam-Berry lens 350, and the light retro-reflector 140 is a plane mirror. Therefore, the Pancharatnam-Berry lens 350 is arranged between the extraction waveguide 1 and the reflective end 4.

[0579] exist Fig.28A In an alternative embodiment, the extraction waveguide 1 is shown having an extraction reflector 174 arranged between a plurality of plates 180, but other extraction reflectors described hereinbefore may be provided as an alternative.

[0580] In operation, the Pancharatnam-Berry lens 350 provides optical power in the lateral direction 195 (350) and provides no optical power in the transverse direction 197 (350). The Pancharatnam-Berry lens 350 thus provides similar operation to the curved reflective end 4 and the curved reflective end 4 with lens 95 described above. In an alternative embodiment (not shown), the reflective end 4 may include a curved mirror, and the optical power of the laterally anamorphic assembly 110 may be shared between the Pancharatnam-Berry lens 350 and the curved reflective end 4. Advantageously, aberrations may be improved.

[0581] Fig.28B is a schematic diagram illustrating the optical structure of the Pancharatnam-Berry lens 350 in end view; and Fig.28C is illustrated in front view Fig.28B Schematic diagram of the optical structure of the Pancharatnam–Berry lens. FIG. 28B to FIG. 28C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0582] Fig.28B and Fig.28C An alternative embodiment of the invention illustrates a Pancharatnam-Berry lens 350 that includes liquid crystal molecules 354 disposed on an orientation layer 352 and a supporting substrate 355. The orientation layer 354 provides a component 357 of the director direction (generally the direction of the extraordinary refractive index) of the liquid crystal molecules 354 that varies across the Pancharatnam-Berry lens 350 in the lateral direction 195. In the lateral direction 197 (350), there is no variation in the component 357 of the director direction, so the Pancharatnam-Berry lens 350 does not provide phase shift modulation.

[0583] During fabrication, the orientation layer 352 may be formed, for example, by exposing and curing the photo-orientation layer with circularly polarized light having a desired phase profile to achieve a change in the optical axis direction 357. More specifically, an interference pattern is created between two oppositely circularly polarized wavefronts that creates localized linearly polarized light whose orientation varies in the plane of the orientation layer to provide the desired orientation profile through the orientation layer 352. The orientation layer is thus oriented with linearly polarized light to provide the optical axis direction 357 in the layer of liquid crystal material 354, which provides the desired optical power profile.

[0584] The layer of liquid crystal material 354 may have a thickness g, which has a half-wave thickness at a desired wavelength of light (e.g., 550 nm). Liquid crystal material 354 may be a solidified liquid crystal material such as a liquid crystal polymer, or may be a nematic liquid crystal material disposed between opposing alignment layers.

[0585] Fig.29 This diagram is for Fig.28B Schematic plot of the phase difference of an illustrative Pancharatnam-Berry lens as a function of lateral position. Fig.29 The figure illustrates a profile 358A of phase delay across the Pancharatnam-Berry lens 350 across the end 4 in the lateral direction 195 for a monochromatic circularly polarized plane wave incident on the Pancharatnam-Berry lens 350. The spacing Λ of the profile of the phase across the Pancharatnam-Berry lens 350 varies across the lateral direction 195 to achieve the profile 358A, with a large spacing at location 161, which may be the center of the Pancharatnam-Berry lens 350, and a decreasing spacing Λ on both sides. Fig.28B As illustrated in , the liquid crystal material director rotates across the spacing Λ, which provides a phase difference to circularly polarized incident light and therefore provides a deflection of the incident wavefront.

[0586] At one site 161 of the Pancharatnam-Berry lens 350 (typically the center of the end 4 of the extraction waveguide 1), the liquid crystal molecules 354 are oriented so that there is no relative phase difference. Contour 358A illustrates phase modulation for a first circular polarization state (which may be a right-handed circular polarization state), and contour 358B illustrates phase modulation for a second circular polarization state (which may be a left-handed circular polarization state) orthogonal to the first polarization state.

[0587] Fig.30 A schematic diagram illustrating the operation of the lateral deformation assembly 110 is illustrated in a front view with a portion of the Pancharatnam-Berry lens 350 providing a lateral deformation assembly 110 across the end 4 of the extraction waveguide 1 in the lateral direction 195 . Fig.30 Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0588] Light rays 440 , 442 incident on the Pancharatnam-Berry lens 350 and propagating along the direction 191 of the extraction waveguide 1 are polarized in a linear polarization state 902 .

[0589] For light ray 440 at location 161, incident polarization state 902 is transmitted with a phase difference by polarization control retarder 72 to provide circular polarization state 922. The Pancharatnam-Berry lens 350 uses polarization control retarder 72 (which is the same retarder used to optimize transmission and reflectivity) for polarized light that extracts the dielectric layer of reflectors 170, 174, thereby advantageously achieving improved efficiency.

[0590] The Pancharatnam-Berry lens 350 does not provide relative phase modulation at position 161 so that reflection of the light 440 from the optical retroreflector 140 provides an orthogonal circular polarization state 924, which is transmitted as polarization state 924 along direction 193 back toward the extraction element 270, which can be a reflector of the extraction reflectors 170, 174, 218 described above.

[0591] For the offset distance X from the site 161 in the lateral direction 195 L 902 is transmitted again by the polarization control retarder 72 with a phase difference to provide a circular polarization state 922. The Pancharatnam-Berry lens 350 provides a phase difference gradient so that the light ray 442 representing the plane phase front is deflected compared to the illustrative undeflected light ray 444. After reflection from the light retro-reflector 140, a further phase shift is provided by the Pancharatnam-Berry lens 350 so that the light ray 442 undergoes further deflection. The reflected light ray 442 propagating in the direction 193 along the extraction waveguide 1 is parallel to the returning light ray 440. Thus, the Pancharatnam-Berry lens 350, the light retro-reflector 140 and the polarization control retarder 72 achieve the desired optical function of the lateral deformation component 110.

[0592] Advantageously, the physical size of the lateral morphing component 110 is reduced and a more compact arrangement is achieved. The phase profile may further provide correction for aberrations of the lateral morphing component 110 .

[0593] In other embodiments, a plurality of Pancharatnam-Berry lenses 350 or a plurality of Pancharatnam-Berry lenses 350 may be used in conjunction with, for example, Fig.25A A Pancharatnam-Berry lens 350 in combination with the refractive lens 95 and the curved reflective end 4 illustrated in FIG. 1 may be provided, the refractive lens 95 and the curved reflective end 4 may be separated in the direction 191 along the extraction waveguide 1. Improved aberration control may be achieved, and the exit pupil 40 may be expanded in the lateral direction 195. Advantageously, Figure 1FThe blurred ellipse may have a reduced width of 455.

[0594]

[0046] Lenses for use with anamorphic near-eye display device 100 will now be described.

[0595] Fig.31A is a schematic diagram illustrating the operation of the anamorphic near-eye display device 100 further including a lens 290 in a side view. Fig.31A Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0596] Fig.31A and other embodiments disclosed herein are further examples of a head mounted display device 600 including a lens 660 having optical power, with the deformable near-eye display device 100 covering the lens 660 .

[0597] The anamorphic near-eye display device 100 described above provides a virtual image 36 located in the far field so that the nominal viewing distance Z v It may be desirable to provide a distance Z to the virtual image plane 33 of the virtual image 36 provided by the anamorphic near-eye display device 100 v Modifications.

[0598] The head mounted display device 600 further includes at least one lens 290, which may be a corrective lens having an optical power for correcting vision. The correction of vision may, for example, correct presbyopia, astigmatism, myopia, or hyperopia of the display user 45.

[0599] Lens 290 may further or alternatively be used to provide virtual image 33 so that distance Z v is a focal plane modifying lens at infinite distance. Such an arrangement can provide focus cues suitable for the display user 47 so that the virtual image desired to be close to the user 47 is provided at the desired focus distance. In stereoscopic display applications, the focus correction of the lens 290 can be arranged to approximate the convergence distance of the image. Focus-convergence mismatch can be reduced, and advantageously, visual stress is reduced, thereby improving comfort of use.

[0600] Such a lens 290 can be used, for example, FIG. 23A to FIG. 23B Glasses head mounted display device 600 or Fig.25A In a virtual reality head mounted display device 600.

[0601] It may be desirable to adjust the focus distance Z of the virtual image v .

[0602] Fig.31Bis a schematic diagram illustrating the operation of the anamorphic near-eye display device 100 further including a Pancharatnam-Berry lens 386 in side view. Fig.31B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0603] exist Fig.31B In an alternative embodiment, the deformable near-eye display device 100 is arranged to direct the output light 401 into a lens 290, which includes a switchable optical stack.

[0604] The switchable optical stack comprises an input polarizer 380, transparent substrates 381A, 381B having an electrically switchable liquid crystal layer 384 provided therebetween, and a quarter wave retarder 382. In a first state, the liquid crystal layer 384 is arranged to provide no polarization rotation of polarized light from the polarizer 380, and the switchable optical stack provides a first circularly polarized output polarization state 383A. In a second state, the liquid crystal layer 384 is arranged to provide polarization rotation of polarized light from the polarizer 380, and the switchable optical stack provides a second circularly polarized output polarization state 383B orthogonal to the polarization state 383A.

[0605] The Pancharatnam-Berry lens 386 includes the Fig.29 The circularly symmetric orientation of the liquid crystal molecules across each radius of the circularly symmetric orientation is similar to the orientation illustrated in A across the lateral direction 195 but different. The Pancharatnam-Berry lens 386 thus provides a circularly symmetric first phase radius profile and a circularly symmetric second phase radius profile, the circularly symmetric first phase radius profile being similar to Fig.29 B for light having polarization state 383A, the circularly symmetric second phase radius profile is similar to Fig.29 B for light having polarization state 383B. The output polarization state from Pancharatnam-Berry lens 386 is analyzed by quarter wave retarder 387 and linear polarizer 388.

[0606] The output light from lens 290A (having either positive or negative power modification of the wavefront from the anamorphic near-eye display device 100) is then incident on fixed lens 290B so that eye 45 observes one of two power corrections.

[0607] Considering the virtual image 34, the absence of lens 290A will be at distance Z v In the first state of the liquid crystal layer 384, a virtual image 334A is provided at a distance Z. v With interval ΔZ A; and in the second state of the liquid crystal layer 384, the virtual image 334B is provided with a distance Z v With interval ΔZ B .

[0608] In an alternative embodiment, lens 290B may be provided by a Pancharatnam-Berry lens. Advantageously, the thickness may be reduced.

[0609] The lenses 290A, 290B thus achieve an adjustable focus distance for the virtual images 334A, 334B. A stack of lenses 290A with, for example, a geometric sequence of power adjustments can be provided to achieve improved fidelity at the location of the virtual image 334. Focus conflicts with the provided image can be advantageously reduced, and image comfort can be improved. Comfortable use time for the head mounted display device 600 can be extended.

[0610] It may be desirable to provide a virtual image 34 that does not have infinite conjugation while not modifying the real image 30 magnification or distance Z. R .

[0611] Fig.32A is a schematic diagram illustrating, in side view, a head mounted display device 600 including a first focal plane modifying lens 290A and a second focal plane modifying lens 290B. Fig.32A Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0612] exist Fig.32A In an alternative embodiment, the deformable near-eye display device 100 is arranged between focal plane modification lenses 290A, 290B. Lens 290A is arranged to modify the distance Z to the virtual image 34 by deflecting light 482 from the deformable near-eye display device 100. v The focal plane of the lens is modified.

[0613] Lens 290B is a correction lens arranged to correct the optical power of lens 290A so that light rays 484 from real image 30 are not deflected by head mounted display device 600. Advantageously, virtual image 34 can be provided in the vicinity of the eye, for example to provide a user interface superimposed with the real world image, thereby advantageously reducing degradation of real world image 30.

[0614] Lenses 290A, 290B may be Pancharatnam-Berry lenses as described above, such that the distance Z Vcan be modified corresponding to the desired image data. Lenses 290A, 290B can have the same optical design, and lens 290B can be driven in an opposite output to lens 290A to achieve a resulting zero focus of lenses 290A, 290B. Advantageously, cost and complexity can be reduced.

[0615] Fig.32B is a schematic diagram illustrating a head mounted display device 600 in side view, the head mounted display device 600 including a plurality of extraction waveguides and further including a first focal plane modifying lens and a second focal plane modifying lens. Fig.32B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0616] exist Fig.32B In an alternative embodiment, two deformable near-eye display devices 100A, 100B are provided to realize multiple virtual images 34A, 34B. The performance of the head-mounted display device can be improved, for example, as described above for Fig.25D Further, the focal plane modifying lenses 290A, 290B are provided with Fig.32A Advantageously, the real world image 30 may be provided with reduced degradation.

[0617] It may be desirable to provide a plurality of optical components having different focal lengths Z. v A. Z v Virtual images 34A and 34B of B.

[0618] Fig.32C is a schematic diagram illustrating a head mounted display device 600 in side view, the head mounted display device 600 including a plurality of extraction waveguides and three focal plane modifying lenses 290A, 290B, 290C. Fig.32C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0619] and Fig.32B Compared with the implementation scheme, Fig.32C In an alternative embodiment of , a further focal plane modifying lens 290C is provided to receive light from the anamorphic near eye display device 100A and pass the light to the further anamorphic near eye display device 100B. Virtual image distance Z for light from one of the anamorphic near eye display devices 100A v A is different from the virtual image distance Z for light from at least one other near-eye display device 100B v B. Multiple focal planes 33A, 33B may advantageously enable increased image comfort.

[0620] Lens 290C cooperates with lens 290A to provide second virtual image 34B, and lens 290B cooperates with lenses 290A, 290C to provide zero total optical power. In an alternative embodiment (not shown), lens 290B can be omitted, for example for virtual reality applications. Advantageously, cost and complexity can be reduced.

[0621] It may be desirable to improve the performance of a virtual reality head mounted display device by providing enhanced control of the focal plane 33 , 633 .

[0622] Fig.32D is a schematic diagram illustrating a head mounted display device 600 in side view, the head mounted display device 600 including a non-deformed near eye display device 610 and a deformed near eye display device 100 . Fig.32D Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0623] and Fig.26A Compared with the implementation scheme, Fig.32D In an alternative embodiment of the present invention, the non-anamorphic near eye display device 610 includes an actuator 612 arranged to move the further spatial light modulator 648 in relation to the non-anamorphic magnification optical system 660 to adjust the magnification of the non-anamorphic near eye display device 100. The virtual image distance 663 provided by the light rays 482 for light from the anamorphic near eye display device 100 is different from the virtual image distance 661 provided by the light rays 482 for light from the non-anamorphic near eye display device 610. The distance F may be adjusted corresponding to the desired image data that may be responsive to the measured viewing direction of the eye 45.

[0624] Advantageously, user comfort may be improved.

[0625] Fig.32E is a schematic diagram illustrating a head mounted display device 600 in side view, the head mounted display device 600 including a non-deformed near eye display device 610 , a deformed near eye display device 100 , and a focal plane modifying lens 290 . Fig.32E Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0626] exist Fig.32DIn an alternative embodiment, an additional focal plane modifying lens 290 is provided between the non-deformed near eye display device 610 and the deformed near eye display device 100. The lens 290 may include a controllable Pancharatnam-Berry lens. The actuator 612 may optionally be omitted. The range of focal lengths ΔZ v A can be increased and the control speed can be improved. User comfort can advantageously be improved.

[0627] Fig.32F is a schematic diagram illustrating a head-mounted display device in a side view, the head-mounted display device including a non-deformed near-eye display device 610, a deformed near-eye display device 100, and a focal plane modifying lens 290, wherein the focal plane modifying lens 290 is arranged to receive light from the non-deformed near-eye display device and the deformed near-eye display device. Fig.32F Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0628] exist Fig.32F In an alternative embodiment of the invention, the focal plane modification lens 290 is arranged to provide a finite virtual image distance 33, 633. Further, the focal plane modification lens 290 may be controllable to achieve a variable focal plane distance ΔZ from the display 610, 100, respectively. v A. ΔZ v B. User comfort can advantageously be improved.

[0629] Figure 32G is a schematic diagram illustrating, in side view, a head mounted display device 600 including a non-deformed near eye display device 610, a deformed near eye display device 100, and two focal plane modifying lenses 290A, 290B. Figure 32G Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0630] and FIG. 32E to FIG. 32F Compared with the implementation scheme, Figure 32G In an alternative embodiment, the focal plane modifying lenses 290A, 290B are arranged with an anamorphic near-eye display device 100 provided therebetween. A focal plane control of the two virtual images 33, 633 may be provided. Advantageously, user comfort may be further improved.

[0631] Fig.32His a schematic diagram illustrating, in side view, a head mounted display device 600 including a non-deformed near-eye display device 610, two deformed extraction waveguides 1100A, 110B, and focal plane modifying lenses 290A, 290B. Fig.32H Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0632] exist Fig.32H In an alternative embodiment, multiple images 33A, 33B, 634 may be provided with multiple focus ranges ΔZ that may overlap. v A. ΔZ v B. ΔZ v C. A focal plane control of the virtual image 33A, 33B, 633 may be provided. Advantageously, user comfort may be further improved.

[0633] Alternative arrangements of the lighting system and the lateral deformation assembly 60 will now be described.

[0634] Fig.33A is a schematic diagram illustrating details of an arrangement of a transverse lens 61 in side view, the transverse lens 61 forming the transverse optical assembly 60; and Fig.33B is illustrated in front view Fig.33A Schematic diagram of a detail of the arrangement of the lateral lens 61. FIG. 33A to FIG. 33B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0635] exist Fig.33A In an alternative embodiment, the lateral lens 61 forming the lateral deformation assembly 60 comprises a composite lens 61A to 61C. Further, the composite lens 61A to 61C may comprise a lens 61D, which comprises the curved input end 2 of the extraction waveguide 1 . Fig.33B The illustration shows that the illumination system 240 and the lateral deformation assembly 60 do not provide optical focal length in the lateral direction 195, that is, the composite lenses 61A to 61D are cylindrical or elongated with an aspheric surface profile (e.g., an aspheric surface as illustrated by the shape of lenses 61A to 61B) to achieve improved field aberrations and advantageously increase the MTF at higher field angles.

[0636] Advantageously, aberrations in the lateral direction 197 ( 60 ) may be improved.

[0637] Further, the illumination system may include a reflective spatial light modulator 48, an illumination array 302 including light sources 304, and a beam combiner cube arranged to illuminate the spatial light modulator 48. The illumination array 302 may include light sources of different colors so that the spatial light modulator 48 may provide time-sequential colored illumination.

[0638] Fig.33A Further illustrating that the lateral anamorphic component 60 may include a lateral diffractive component 67 provided with optical power in a lateral direction 197. Component 67 may have an angle-dependent chromatic aberration to correct for chromatic aberration from refractive components 60A to 60D in the lateral direction 197. Color blur in the lateral direction 197 may advantageously be reduced.

[0639] Fig.34A is a schematic diagram illustrating in side view a spatial light modulator arrangement 50 for use in the deformed near-eye display device 100 of FIG. 1 including separate red, green, and blue spatial light modulators 48R, 48G, 48B and a beam combining element 82 . Fig.34A Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0640] Fig.34A An alternative embodiment of the illustrated illumination system 240 may include a red spatial light modulator 48R, a green spatial light modulator 48G, and a blue spatial light modulator 48B and a color combining prism arranged to direct light rays 412R, 412G, 412B toward the lateral anamorphic assembly 60. Such an arrangement may be used to provide a high resolution color image from, for example, the emissive spatial light modulator 48. The emissive display may be, for example, an OLED on silicon or a micro-LED on silicon spatial light modulator. Advantageously, a high resolution color virtual image may be provided.

[0641] Fig.34B is a diagram illustrating in side view a method for folding a birdbath in a manner including a birdbath arrangement Figure 1A Schematic diagram of the illumination system 240 and the lateral deformation component 60 used in the deformable near-eye display device 100. Fig.34B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0642] exist Fig.34BIn an alternative embodiment of the invention, the spatial light modulator 48 illuminates a catadioptric illumination system 240 comprising an input lens 79, a curved mirror 86A and a partial reflector 81 so that the light 412 is directed into the input side 2 of the extraction waveguide 1. Advantageously, chromatic aberrations in the lateral direction 197 can be reduced. The partial reflector 81 can be a polarizing beam splitter or can be, for example, a thin metallized layer.

[0643] Additionally or alternatively, a curved mirror 86B may be provided to improve operating efficiency.

[0644] Fig.34C is a schematic diagram illustrating, in side view, an arrangement of a spatial light modulator 48 for use in an anamorphic near-eye display device including a laterally anamorphic component 60 that includes a reflector 62 . Fig.34C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0645] and Figure 1A Compared to the embodiment of the present invention, the illumination system 240 includes a spatial light modulator 48, a reflector 62, and a curved input end 2. The lateral anamorphic component 60 is an illustrative example of a catadioptric optical element, which includes a reflective surface and a refractive surface of the reflector 62 and the input end 2, respectively. In other embodiments (not shown), the refractive component can be omitted, and the lateral anamorphic component 60 can include only a reflective surface with optical power, and the input end 2 can be planar. Compared to the refractive lens 61 described above, the chromatic aberration of the light 414 input into the extraction waveguide 1 can be advantageously reduced.

[0646] An alternative arrangement of the lateral deformation assembly 60 including the input reflector 62 will now be described.

[0647] Fig.35A is a schematic diagram illustrating a front perspective view of a deformed near-eye display device 100 including an input reflector 62; Fig.35B It is a graphic illustration Fig.35A A schematic diagram of a side view of a deformed near-eye display device 100; and Fig.35C It is a graphic illustration Fig.35A Schematic diagram of a front view of a deformed near-eye display device 100. FIG. 35A to FIG. 35C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0648] In order to clearly explain the input section 12, FIG. 35A to FIG. 35GIn an alternative embodiment, the polarization-sensitive reflector 700 and the array of extraction features 170 are not illustrated. In construction, various embodiments of the polarization-sensitive reflector 700 and the array of extraction features 170 as described elsewhere herein are provided with the waveguide 1 to achieve light extraction.

[0649] Compared with Figure 1, FIG. 35A to FIG. 35C In an alternative embodiment of the optical system 250, the input section 12 includes an input reflector 62, which is a transverse deformation component 60 and is arranged to reflect light from the illumination system 240 and guide it along the waveguide 1. The input section 12 further includes an input face 122, which is arranged on the front side 8 or the rear side 6 of the waveguide 1 and faces the input reflector 62, and the input section 12 is arranged to receive light from the illumination system 240 through the input face 122, wherein the input face 122 is arranged outside one of the front guide surface 8 or the rear guide surface 6, and the input section 12 is integral with the waveguide 1. The input section 12 further includes a separation face 28, which extends outwardly from one of the front guide surface 8 or the rear guide surface 6 to the input face 122. The extraction features in the extraction region 284 can be of the type illustrated elsewhere herein.

[0650] FIG. 35A to FIG. 35G Embodiments of the present invention can be made using a molding process, and the reflective material 66 is formed on the curved surface 65 to provide an input reflector, such as by sputtering, evaporation or other known coating methods. Alternatively, the reflective material 66 may include a reflective film, such as ESR from 3M Company. TM Advantageously, the cost and complexity of production can be reduced.

[0651] It may be desirable to provide further control of optical aberrations in the lateral direction 197 .

[0652] Fig.35D is a schematic diagram illustrating a side view of an alternative deformable near-eye display device 100 including an alternative input reflector 62 and lens 61 . Fig.35D Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0653] exist Fig.35DIn an alternative embodiment, the waveguide 1 has an end 2, which is an input face, the waveguide 1 is arranged to receive light from the illumination system 240 through the input face, and the input section 12 is an element separated from the waveguide 1, which further includes an output face 23 and is arranged to guide the light reflected by the input reflector 62 through the output face 23 and into the waveguide 1 through the input face 2 of the waveguide 1.

[0654] The lateral deformation assembly 60 further includes a lens 61, wherein the lens 61 of the lateral deformation assembly 60 is a composite lens 61. The lens 61 may include a refractive element 61A. Further, the lens 61 may include a lens 61B, and the lens 61B includes the curved input surface 2 of the waveguide 1. Further, the lens 61 may include a curved surface 61C and a material 61D, and the material 61D may be air or a material having a refractive index different from the refractive index of the waveguide 1 material. The lenses 61A to 61D may be arranged to reduce Figures 1A to 1D The aberration of the input reflector 62 of the lateral deformation component 60 is thus a catadioptric optical element including a refractive optical function and a reflective optical function. Advantageously, the fidelity of the image can be improved in the lateral direction.

[0655] Fig.35D An alternative embodiment is further illustrated in which the input reflector 62 is disposed on a surface of member 68 A. The surface of the input reflector 62 may advantageously be further protected. Fig.35D An alternative embodiment is further illustrated in which the lateral deformation component 110 is a reflector disposed on a surface of the member 68B. The surface of the extraction reflector 140 can advantageously be further protected. Coatings 66, 67 can be formed on the members 68A, 68B, respectively. Higher temperature processing conditions can be achieved compared to coatings for the polymer waveguide 1. Advantageously, costs can be reduced and operating efficiency can be improved. A gap 69D can be provided between the waveguide 1 end 4 and the member 68B, wherein the gap 69D can include air or a bonding material (such as an adhesive).

[0656] exist Fig.35D In an alternative embodiment, the input section 12 is not integral with the waveguide 1. The waveguide 1 has an end, the end being the input face 2, the waveguide 1 being arranged to receive light from the illumination system 240 through the input face 2, and the input section 12 is an element separate from the waveguide 1, the element further comprising an output face 23, and being arranged to guide light reflected by the input reflector 62 through the output face 23 and into the waveguide 1 through the input face 2 of the waveguide 1. Further, the lateral deformation component 60 is disposed outside the waveguide 1, and the waveguide 1 is arranged to receive light 400 from the lateral deformation component 60 through the input face 2. In other words, Fig.35DFurther illustrating an alternative embodiment, in which the input section 12 and the guide section 10 of the waveguide 1 are formed of separate components 69A, 69B, respectively, and aligned across a gap 69C, which may include air or a bonding material (such as an adhesive). The components 69A, 69B can be formed separately during manufacturing, thereby reducing the processing complexity of the surface of the waveguide 1 and advantageously improving production yields.

[0657] It may be desirable to increase the size of spatial light modulator 48 in the lateral direction.

[0658] FIG. 35E to FIG. 35G is a schematic diagram illustrating an alternative embodiment of a deformed near-eye display device 100 including an input reflector 62 in side view. FIG. 35E to FIG. 35G Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0659] exist FIG. 35E to FIG. 35F In an alternative embodiment, the input face 122 extends parallel to the front guide surface 8 when the input face 122 is on the front side of the waveguide 1, or extends parallel to the rear guide surface 6 when the input face 122 is on the rear side of the waveguide 1. Fig.35E The input face 122 is comprised, which is coplanar with the front guide surface 8 in the case where the input face 122 is on the front side of the waveguide 1, or coplanar with the rear guide surface 6 in the case where the input face 122 is on the rear side of the waveguide 1. Advantageously, the spatial light modulator 48 can be provided on a driver board of larger size.

[0660] exist Fig.35F In an alternative embodiment, the input face 122 is offset and parallel to the front guide surface 8 in the case where the input face 122 is on the front side of the waveguide 1, or is offset and parallel to the rear guide surface 6 in the case where the input face 122 is on the rear side of the waveguide 1. Advantageously, the spatial light modulator 48 can be provided in or near the arm 604 of the headgear 600.

[0661] exist Figure 35G In an alternative embodiment, the input face 122 extends at an acute angle θ to the front guide surface 8 in case the input face 122 is on the front side of the waveguide 1, or extends at an acute angle θ to the rear guide surface 6 in case the input face 122 is on the rear side of the waveguide 1. Advantageously, a more convenient mechanical arrangement may be provided.

[0662] exist FIG. 35E to FIG. 35G In an alternative embodiment, the extracted features can be of the type illustrated elsewhere herein.

[0663] Fig.36A is a schematic diagram illustrating an alternative arrangement of the input focusing lens 61 in a perspective front view. Fig.36A Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0664] Spatial light modulator 48 includes active region 49A and boundary 49B, and is aligned with the lenses of lateral anamorphic assembly 60, which is a composite lens including lenses 60A to 60F. Some of lenses 60A to 60F may include surfaces with constant radius, and some may include variable radius surfaces so that aberration correction is advantageously improved in combination.

[0665] Alternative arrangements of spatial light modulator 48, illumination system 240, and optical system 250 will now be described.

[0666] Fig.36B is a schematic diagram illustrating in side view a spatial light modulator arrangement for use in the deformed near-eye display device of FIG. 1 , the spatial light modulator arrangement comprising a spatial light modulator 48 including a laser 50 , a scanning arrangement 51 and a light diffusing screen 52 . Fig.36B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0667] exist Fig.36B In an alternative embodiment, the spatial light modulator 48 comprises a laser 50 arranged to direct a light beam 490 towards a scanning arrangement 51 which may be, for example, a rotating mirror having an oscillation 53 which is synchronized with the image data.

[0668] The light beam 490 is arranged to illuminate the screen 52 to provide a diffuse light source 55 at the screen. The screen 52 may include a diffusing arrangement so that the transmitted light is diffused into a light cone 491 arranged to provide input light rays 492 into the lateral deformation component 60 and the extraction waveguide 1.

[0669] The screen 52 may alternatively comprise a light emitting layer, such as a phosphor laser, with the laser beam 490 being arranged to produce emission from the light emitting layer at the phosphor laser. The output color may advantageously be independent of the emission wavelength of the laser 50. Further, laser speckle may be reduced.

[0670] Laser 50 may include a one-dimensional array of lasing pixels 222 across rows 221T, and scanning arrangement 51 may provide a one-dimensional array of light sources 55 for each addressable row of spatial light modulator 48 at screen 52. The scanning speed of scanning arrangement 51 is reduced, thereby advantageously achieving reduced cost and complexity.

[0671] Alternatively, the laser 50 may comprise a single laser emitter, and the scanning arrangement 51 may provide two-dimensional scanning of the light beam 490 to achieve a two-dimensional array of pixels of the emitter 55 at the screen 52. Advantageously, the laser 50 cost may be reduced.

[0672] A further arrangement comprising a laser source will now be described.

[0673] Fig.37A is a schematic diagram illustrating, in side view, the input of an extraction waveguide 1 comprising a spatial light modulator 48 including a laser source and a deflector element 50; Fig.37B is a schematic diagram illustrating a spatial light modulator 48 in front view, the spatial light modulator 48 comprising Fig.37A A row of laser light sources 222A to 222N used in an arrangement of; and Fig.37C is a schematic diagram illustrating alternative lighting arrangements. FIG. 37A to FIG. 37C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0674] Fig.37A An alternative embodiment comprises a lateral deformation assembly 60 formed by a deflector element 50 comprising a scanning mirror 51 .

[0675] Fig.37B The diagram illustrates a spatial light modulator 48 comprising a one-dimensional array of pixels 222A to 222N suitable for use in the arrangement of Figure 37, wherein the pixels 222A to 222N each comprise a laser source. The control system 500 is arranged to supply image data one row at a time to the spatial light modulator 48 controller 505, which outputs the pixel data to the laser pixels 222A to 222N by means of a driver 509, and outputs the position data to the deflector element 50 by means of a scanner driver 511. The laser pixels 222A to 222N are arranged to have a pitch P in the lateral direction 195. L A row, with a spacing P in the lateral direction 195 L With e.g. Figure 2D The spacing is the same as shown in the figure.

[0676] Return to Fig.37A1 , in operation, image data for a first addressed row of image data is applied to laser pixels 222A to 222N, and deflector element 50 is adjusted so that laser light from spatial light modulator 48 is directed as light ray 490A in a first direction across transverse direction 197. At different times, image data for different addressed rows of image data are applied to laser pixels 222A to 222N, and deflector element 50 is adjusted so that laser light from spatial light modulator 48 is directed as light ray 490B in different directions across transverse direction 197. Laterally morphing assembly 60 is thus arranged to receive light from spatial light modulator 48, and illumination system 240 is arranged so that light output from laterally morphing assembly 60 is directed in cone 491 in directions as illustrated by light rays 490A, 490B distributed across transverse direction 197.

[0677] In other words, the deflector element 50 is scanned about the lateral direction 197 (60) and is used to sequentially provide the illustrative light rays 490A, 490B. By means of the sequential scanning, the deflector element 50 effectively has a positive optical focal length in the lateral direction 197 (60) for the light from the spatial light modulator 48, thereby realizing the output cone 491 in a sequential manner. In this way, the deflector element 50 guides the light into directions distributed in the lateral direction so that it can be used as a lateral deformation component 60. The scanning of the deflector element 50 can be arranged not to guide the light near or parallel to the direction 191 along the extraction waveguide 1. Advantageously, double imaging is reduced.

[0678] Advantageously, the cost and complexity of the lighting system 240 and the lateral deformation assembly 60 may be reduced.

[0679] Fig.37C An alternative embodiment provides a beam expander 61A, 61B that increases the width 63 of the output beam from the illumination system 240. Fig.37C , the illumination system 240 further comprises a deflector element 50 arranged to deflect light output from the lateral morphing assembly 60 by a selectable amount, the deflector element 50 being selectively operable to direct light output from the lateral morphing assembly 60 into directions distributed in the lateral direction 197. Advantageously, uniformity of the output image from across the exit pupil 40 is provided.

[0680] It may be desirable to provide tracking sensors to determine the location of the viewer's pupils.

[0681] Fig.38A is a schematic diagram illustrating, in a perspective front view, an anamorphic near-eye display device 100 including an eye tracking arrangement 750; Fig.38B is a schematic diagram illustrating in side view an anamorphic near-eye display device 100 including an eye-tracking arrangement 750 having a transmissive aperture 752 arranged at a reflective end; and Fig.38C is a schematic diagram illustrating an anamorphic near-eye display device 100 in side view including an eye tracking arrangement 750 having a partially transflective reflector arranged with an optical retroreflector 140 . FIG. 38A to FIG. 38C Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0682] exist Fig.38C In an alternative embodiment, the extraction waveguide 1 is shown having a stepped extraction feature 170, but other extraction reflectors (such as those described above) may be provided as an alternative.

[0683] exist FIG. 38A to FIG. 38B In an alternative embodiment of the invention, an aperture is provided in the light retro-reflector 140. In operation, some light from the eye 45 may be reflected into the extraction waveguide 1 and directed toward the light retro-reflector 140. Some light rays 760 incident on the aperture 752 are directed onto an optional lens 756 and an optical sensor 754, which is arranged to collect received image data for the locations 745 at the sensor of the image of the eye 45. The image of the eye 45 may be directed to the plurality of locations 745 from the respective extraction features 170 and from the guidance of light in the extraction waveguide 1. A machine learning algorithm may be executed in the position location estimation unit 545 to determine the most likely eye 45 location based on the image with the location 745 from the sensor 754. The eye location data is returned to the control system 500. The control system may be adjusted to optimize the image quality for the measured eye 45 location, thereby advantageously improving the image quality.

[0684] exist Fig.38C In an alternative embodiment, the light retroreflector 140 may be partially transmissive, for example for infrared illumination of the eye 45 by light rays 707 provided by a light source 756 disposed at the input end 2 of the extraction waveguide 1. Advantageously, improved uniformity of image data output to the eye 45 may be achieved.

[0685] The lighting system 240 and the optical system 250 of the above embodiment may be provided for a modified directional lighting device for illumination of an external scene 479 .

[0686] Fig.39Ais a schematic diagram illustrating a deformed directional lighting device 1000 in a front perspective view, the deformed directional lighting device 1000 being arranged to illuminate a scene 479. Fig.39A Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0687] Fig.39A An alternative embodiment of the invention illustrates a deformed directional lighting device 1000, which includes an illumination system 240, which includes an array of light sources 948, and the illumination system is arranged to output light. The light source array 948 can, for example, include an array of light emitting diodes, or can be provided by a spatial light modulator 48 as described elsewhere herein.

[0688] The optical system 250 is arranged to direct light from the illumination system 240. Light in the light cone 499 may be directed toward an external illuminated scene 479. The illuminated scene 479 may include, but is not limited to, a road, a room, an exterior space, processing equipment, a metrology environment, a theatrical stage, a human body (e.g., for facial lighting for facial detection and measurement purposes).

[0689] The optical system 250 has an optical axis 199 and has deformation properties in a lateral direction 195 and a transverse direction 197 that are perpendicular to each other and perpendicular to the optical axis 199, wherein the light source array 948 includes light sources 949a to 949n distributed in the lateral direction 195, and as described elsewhere in this document, the light sources 949a to 949n can be further distributed in the transverse direction 197.

[0690] The optical system 250 further includes a lateral deformation component 60 having positive optical power in the lateral direction 197, wherein the lateral deformation component 60 is arranged to receive light from the light source array 948, and the illumination system 250 is arranged so that the light output from the lateral deformation component 60 is guided in a direction distributed in the lateral direction 197.

[0691] The optical system 250 further includes an extraction waveguide 1 and a lateral deformation component 110, wherein the extraction waveguide 1 is arranged to receive light from the lateral deformation component 60, the lateral deformation component 110 has positive optical power in the lateral direction 195, and the extraction waveguide 1 is arranged to guide the light in the light cone 491 along the extraction waveguide 1 to the lateral deformation component 110 in the first direction 191.

[0692] The light retro-reflector 140 is arranged to reflect light that has been guided along the extraction waveguide 1 in a first direction 191 such that reflected light in the light cone 493 is guided along the extraction waveguide 1 in a second direction 193 opposite to the first direction 191 .

[0693] The extraction waveguide 1 includes: a front guiding surface 8; a polarization-sensitive reflector 700, which is opposite to the front guiding surface 8; and an extraction element 270, which is arranged outside the polarization-sensitive reflector 700, and the extraction element 270 includes: a rear guiding surface 6, which is opposite to the front guiding surface 8; and at least one extraction feature 970; the deformed directional lighting device 1000 is arranged to provide an input linear polarization state 902 for the light in the cone 491 guided along the extraction waveguide 1 in the first direction 191 before the light in the cone 491 guided along the extraction waveguide 1 in the first direction 191 reaches the polarization-sensitive reflector 700; and the optical system further includes a polarization conversion retarder 72 arranged between the polarization-sensitive reflector 700 and the light reverse reflector 140, wherein the polarization conversion retarder 72 is arranged to convert the light passing through the polarization conversion retarder 72 between the linear polarization state and the circular polarization state. The polarization state of light, and the polarization conversion delay 72 and the light reverse reflector 140 are combinedly arranged to rotate the input linear polarization state 902 of the light guided in the first direction 191, so that the light guided in the second direction 193 and output from the polarization conversion delay 72 has an orthogonal linear polarization state 904 orthogonal to the input linear polarization state 902; the polarization-sensitive reflector 700 is arranged to reflect the light in the cone 491 having the input linear polarization state 902 guided in the first direction 191 and transmit the light having the orthogonal linear polarization state 904 guided in the second direction 193, so that the front guiding surface 8 and the polarization-sensitive reflector 700 are arranged to guide the light in the first direction 191, and the front guiding surface 8 and the rear guiding surface 6 are arranged to guide the light in the second direction 193; and at least one extraction feature 970 is arranged to extract the light guided along the extraction waveguide 1 in the second direction 193 through the front guiding surface 8.

[0694] Fig.39A Variations of directional lighting device 1000 may include various embodiments arranged to improve efficiency and image quality as described elsewhere herein.

[0695] By comparison with the anamorphic near-eye display device 100 described above, the output light from the anamorphic directional lighting device 1000 is provided as an illumination cone 951a-951n for illuminating the scene 479, as compared to angular pixel information for illuminating the pupil 44 and the retina 46. High resolution imaging of the illuminated scene 479 can be achieved in a compact package with high efficiency and low cost.

[0696] Light source 949 may output light that is visible or infrared. Advantageously, directional illumination of scene 479 may be provided for visible illumination or scene illumination of other detectors such as a LIDAR detector. Light source 949 may have different spectral outputs. The different spectral outputs may include: a white light spectrum, a plurality of different white light spectra, red light, orange light, and / or infrared light. Visible illumination may be provided, and further illumination for detection purposes may also be provided, which may have different illumination structures to achieve an improved signal-to-noise ratio for detection.

[0697] In an alternative embodiment, scene 479 may include a projection screen, and deformable directional lighting device 1000 may provide projection of the image onto the projection screen. Advantageously, a lightweight portable image projector with high efficiency may be provided in a thin package.

[0698] Fig.39A The reflective extraction feature 970 may alternatively be provided by an array of light extraction features 970a to 970n. Advantageously, the aesthetic appearance of the directional lighting appearance may be modified. Alternatively, the reflective extraction feature 970 may be provided by at least one of the reflective extraction features 270 as described elsewhere hereinabove, and may include at least one feature such as, but not limited to, extraction reflectors 170, 172, 12, 186, 180, 289 and diffractive extraction features 280, 282. Alternative embodiments of the light source array 948 may be provided by an array of light extraction features 970a to 970n as described hereinabove (e.g., in FIG. 2A to FIG. 2D , Figure 36 and FIG. 37A to FIG. 37C The lateral deformation component 60 may alternatively include the embodiment of the spatial light modulator 48 described in FIG. 17D, Fig.36A , FIG. 33A to FIG. 33B , FIG. 34A to FIG. 34B and one or more lenses illustrated in FIG35. Aberration control and power of the anamorphic assemblies 60, 110 may be achieved by using a lens for use in the lateral anamorphic assembly 110 and / or the transverse anamorphic assembly 60. FIG. 28A to FIG. 28C , Fig.29 and Fig.30 The above features may be provided individually or in combination.

[0699] Further alternative embodiments of the waveguide 1 arrangement, the lateral deformation component 60 arrangement, the lateral deformation component 110 arrangement and the extraction feature 970 arrangement may be provided as described elsewhere hereinabove.

[0700] Fig.39B is a schematic diagram illustrating a side view of a road scene 479 including a vehicle 600, the vehicle 600 including a vehicle exterior light device 106, the vehicle exterior light device 106 including Fig.39A A deformed directional lighting device 1000. Fig.39B Features of the embodiments that are not discussed in further detail may be assumed to correspond to features as discussed above with equivalent reference numerals, including any possible variations in features.

[0701] Fig.39B An alternative embodiment of the present invention illustrates a vehicle exterior light device 106, which includes a vehicle exterior light device 106 as shown in FIG. Fig.39A The deformed directional lighting device 1000 illustrated in the figure is a vehicle exterior light device mounted on a housing 108 for mounting to a vehicle 600. The vehicle exterior light device 106 is arranged to illuminate an external scene 479 (such as a road environment). The vehicle exterior light device 106 provides an output light cone 499 so that a horizontal plane 499 and a road surface 494 can be illuminated. Fig.39B In the example of FIG. 4 , the cross-section of the light cone 499 is distributed across the lateral direction 197 . In an alternative embodiment, the cross-section of the light cone 499 can be distributed across the lateral direction 195 .

[0702] The light source array 948 can be controlled by the controller 500 in response to the location of objects (such as other drivers or road hazards in the illuminated scene 479). The light cones 499 can be arranged to illuminate a two-dimensional array of light cones 951 corresponding to the respective light sources 949. The light sources 949a to 949n can be individually controllable or jointly controllable so that some portions of the scene 479 are illuminated and other portions are not illuminated or illuminated at different illumination levels. Advantageously, glare for other drivers can be reduced while providing an increased level of illumination of the road scene 479.

[0703] Although various embodiments according to the principles disclosed herein have been described above, it should be understood that they are presented as examples only, not limitations. Therefore, the breadth and scope of the present disclosure should not be limited by any of the above exemplary embodiments, but should only be defined in accordance with any claims published from the present disclosure and their equivalents. In addition, the above advantages and features are provided in the described embodiments, but the application of such published claims should not be limited to the process and structure that achieves any or all of the above advantages.

[0704] In addition, the paragraph titles of this article are provided for the suggested consistency under 37CFR 1.77, or for providing organizational clues. These titles should not limit or characterize the one or more embodiments that can be set forth in any claims published from this disclosure. Specifically and as an example, although the title refers to "technical field", the claims should not be limited to describing the so-called technical field by the language selected under the title. Further, the description of the technology in the "background technology" section is not to be interpreted as admitting that a certain technology is the prior art of any one or more embodiments in this disclosure. "Summary of the invention" is also not to be considered as a feature description of one or more embodiments set forth in the published claims. In addition, any reference to the singular "invention" in this disclosure should not be used to prove that there is only one novel point in this disclosure. According to the limitations of multiple claims published from this disclosure, multiple embodiments can be set forth, and these claims accordingly define one or more embodiments protected by them, and their equivalents. In all cases, the scope of these claims should be understood according to the essence of these claims themselves according to this disclosure, and should not be limited by the titles listed herein.

Claims

1. A deformable near-eye display device, the deformable near-eye display device comprising: an illumination system, the illumination system comprising a spatial light modulator, the illumination system being arranged to output light; as well as An optical system arranged to direct light from the illumination system to an eye of a viewer, wherein the optical system has an optical axis and has an anamorphic property in a lateral direction and a transverse direction perpendicular to each other and perpendicular to the optical axis, wherein the spatial light modulator comprises pixels distributed in the lateral direction, and the optical system comprises: a transverse anamorphic component having positive optical power in the transverse direction, wherein the transverse anamorphic component is arranged to receive light from the spatial light modulator, and the illumination system is arranged such that light output from the transverse anamorphic component is directed in directions distributed in the transverse direction; an extraction waveguide arranged to receive light from the lateral deformation component; a lateral anamorphic component having positive optical power in the lateral direction, the extraction waveguide being arranged to guide light from the lateral anamorphic component along the extraction waveguide to the lateral anamorphic component in a first direction; and a light retro-reflector arranged to reflect light directed along the extraction waveguide in the first direction to form light directed along the extraction waveguide in a second direction opposite to the first direction, in: The extraction waveguide comprises: front guide surface; a polarization-sensitive reflector opposite the front directing surface; and an extraction element disposed outside the polarization-sensitive reflector, The extraction element comprises: a rear guide surface, the rear guide surface being opposite to the front guide surface; and Extracting arrays of features; The anamorphic near-eye display device is arranged to provide an input linear polarization state for light guided along the extraction waveguide in the first direction before the light reaches the polarization-sensitive reflector; and The optical system further comprises a polarization conversion retarder disposed between the polarization-sensitive reflector and the light retro-reflector, wherein the polarization conversion retarder is arranged to convert the polarization state of light passing through the polarization conversion retarder between a linear polarization state and a circular polarization state, and the polarization conversion retarder and the light retro-reflector are arranged in combination to rotate an input linear polarization state of light directed in the first direction so that light directed in the second direction and output from the polarization conversion retarder has an orthogonal linear polarization state orthogonal to the input linear polarization state; the polarization-sensitive reflector being arranged to reflect light having the input linear polarization state directed in the first direction and to pass light having the orthogonal linear polarization state directed in the second direction, such that the front guiding surface and the polarization-sensitive reflector are arranged to guide light in the first direction, and the front guiding surface and the rear guiding surface are arranged to guide light in the second direction; and The array of extraction features is arranged to extract light guided along the extraction waveguide in the second direction through the front guide surface towards an eye of a viewer, the array of extraction features being distributed along the extraction waveguide to provide an exit pupil expansion in the lateral direction.

2. The anamorphic near-eye display device of claim 1, wherein the polarization-sensitive reflector comprises a reflective linear polarizer.

3. A morphing near-eye display device according to claim 1 or 2, wherein the polarization-converting retarder has a retardation of one quarter wavelength at a visible light wavelength.

4. A deformable near-eye display device according to any one of the preceding claims, wherein the input linear polarization state is a p-polarization state in the extraction waveguide, or the input linear polarization state is an s-polarization state in the extraction waveguide.

5. A deformable near-eye display device according to any of the preceding claims, wherein the optical system further comprises an input linear polarizer, which is disposed between the spatial light modulator and the polarization-sensitive reflector and is arranged to pass light having the input linear polarization state.

6. The anamorphic near-eye display device of claim 5, wherein the input linear polarizer is disposed between the spatial light modulator and the extraction waveguide.

7. The anamorphic near-eye display device of claim 5, wherein the input linear polarizer is disposed within the extraction waveguide.

8. The deformable near-eye display device according to any one of claims 5 to 7, wherein The input linear polarizer is disposed after the transverse anamorphic component, and The optical system further comprises a polarization-converting retarder disposed between the lateral anamorphic component and the input linear polarizer, the polarization-converting retarder being arranged to convert the polarization state of light passing through the polarization-converting retarder between a linear polarization state and a circular polarization state.

9. A morphing near-eye display device according to any one of claims 5 to 8, wherein the illumination system is arranged to output unpolarized light.

10. A morphing near-eye display device according to any one of claims 1 to 8, wherein the illumination system is arranged to output light having the input linear polarization state.

11. A morphing near-eye display device according to any preceding claim, wherein the extraction features are elongated in the lateral direction.

12. A deformable near-eye display device according to any one of the preceding claims, wherein the rear guiding surface includes extraction facets, the extraction facets being the extraction features, each extraction facet being arranged to reflect light guided in the second direction through the front guiding surface toward the viewer's eyes.

13. The anamorphic near-eye display device of claim 12, wherein the rear guiding surface comprises a plurality of outwardly protruding prisms, each of the prisms comprising at least one extraction facet and at least one draft facet.

14. The anamorphic near-eye display device of claim 13, wherein at least one of the prisms comprises a plurality of draft facets, and an intermediate guiding facet disposed between each adjacent pair of the plurality of draft facets.

15. The anamorphic near-eye display device of claim 13, wherein the prisms each further include a primary guiding facet between the at least one extraction facet and the at least one draft facet.

16. A anamorphic near-eye display device according to any one of claims 13 to 15, wherein the rear guide surface comprises a guide portion between the prisms.

17. The anamorphic near-eye display device of any one of claims 1 to 10, wherein the rear directing surface comprises a surface relief grating comprising the extraction features.

18. A morphing near-eye display device according to any one of the preceding claims, wherein the extraction element comprises an array of extraction reflectors arranged inside the extraction waveguide.

19. The anamorphic near-eye display device of claim 18, wherein the array of extraction reflectors is disposed between the polarization-sensitive reflector and the rear light directing surface.

20. A morphing near-eye display device according to claim 18 or 19, wherein the array of extraction reflectors has a reflectivity defined across their entire area that increases with increasing distance along the extraction waveguide in the second direction.

21. The anamorphic near-eye display device of any one of claims 18 to 20, wherein the extraction reflector comprises extraction surfaces separated by a partially reflective coating.

22. The anamorphic near-eye display device of claim 21, wherein the partially reflective coating comprises at least one dielectric layer.

23. The anamorphic near-eye display device of claim 22, wherein the at least one dielectric layer comprises a stack of dielectric layers.

24. The anamorphic near-eye display device of claim 19, wherein the partially reflective coating is metallic.

25. A deformable near-eye display device according to any one of claims 18 to 24, wherein the extraction reflector extends partially across the extraction waveguide, between the opposing rear guide surface and the front guide surface of the extraction waveguide at a continuously shifted position.

26. The anamorphic near-eye display device of claim 25, further comprising an intermediate reflector extending along the extraction waveguide between adjacent pairs of extraction reflectors.

27. The anamorphic near-eye display device of any preceding claim, wherein the polarization-sensitive reflector comprises at least one dielectric layer.

28. The anamorphic near-eye display device of claim 27, wherein the at least one dielectric layer comprises a stack of dielectric layers.

29. A morphing near-eye display device according to any preceding claim, wherein the polarization-sensitive reflector comprises a nematic liquid crystal layer.

30. The anamorphic near-eye display device of claim 29, wherein the liquid crystal layer comprises a liquid crystal material disposed between opposing first and second alignment layers.

31. A morphing near-eye display device according to claim 29 or 30, wherein a component of the optical axis of the liquid crystal layer in the plane of the liquid crystal layer is parallel or orthogonal to the first direction along the extraction waveguide.

32. A morphing near-eye display device according to any preceding claim, wherein the polarization-sensitive reflector comprises a cholesteric liquid crystal layer.

33. The anamorphic near-eye display device of claim 32, further comprising a polarization-converting retarder disposed between the front guiding surface and the cholesteric liquid crystal retarder, wherein The polarization-converting retarder is arranged to convert the polarization state of light passing through the polarization-converting retarder between a linear polarization state and a circular polarization state, and the polarization-converting retarder and the cholesteric liquid crystal layer are arranged in combination to reflect the input linear polarization state of light guided in the first direction and transmit the linear polarization state of light guided in the second direction.

34. A morphing near-eye display device according to claim 32 or 33, further comprising a polarization-converting retarder arranged between the rear directing surface and the cholesteric liquid crystal retarder, wherein The polarization-converting retarder is arranged to convert the polarization state of light passing through the polarization-converting retarder between a linear polarization state and a circular polarization state.

35. A deformable near-eye display device according to any one of the preceding claims, wherein the extraction waveguide has an input end, the input end extends in the lateral direction and the transverse direction, and the extraction waveguide is arranged to receive light from the illumination system through the input end.

36. The anamorphic near-eye display device of claim 35, wherein the input linear polarizer is disposed between the spatial light modulator and the input end of the extraction waveguide.

37. A deformable near-eye display device according to claim 35 or claim 36, wherein the direction of the optical axis through the lateral deformable component is inclined relative to the first direction and the second direction along the extraction waveguide.

38. A morphing near-eye display device according to any one of claims 35 to 37, wherein the input end is tilted relative to the first direction and the second direction along the extraction waveguide.

39. The anamorphic near-eye display device of claim 38, wherein the polarization-converting retarder has a quarter-wavelength retardation at visible light wavelengths.

40. A morphing near-eye display device according to any preceding claim, wherein the light retro-reflector is a reflective end of the extraction waveguide.

41. A deformable near-eye display device according to any of the preceding claims, wherein the laterally deformable component includes the light retro-reflector.

42. A morphing near-eye display device according to any preceding claim, wherein the laterally morphing component comprises a lens.

43. The anamorphic near-eye display device of claim 42, wherein the lenses of the lateral anamorphic assembly are composite lenses.

44. A deformable near-eye display device according to any of the preceding claims, wherein the optical system includes an input section, the input section includes an input reflector, the input reflector is the lateral deformable component and is arranged to reflect light from the illumination system and guide the light along the extraction waveguide.

45. The anamorphic near-eye display device of claim 44, wherein the lateral anamorphic component further comprises a lens.

46. ​​A deformable near-eye display device according to claim 44 or 45, wherein the input segment further includes an input surface, which is arranged on the front side or the rear side of the extraction waveguide and faces the input reflector, and the input segment is arranged to receive light from the illumination system through the input surface.

47. A deformable near-eye display device according to claim 46, wherein when the input surface is on the front side of the extraction waveguide, the input surface extends at an acute angle to the front guide surface, or when the input surface is on the rear side of the extraction waveguide, the input surface extends at an acute angle to the rear guide surface.

48. A deformable near-eye display device according to claim 46, wherein when the input surface is on the front side of the extraction waveguide, the input surface extends parallel to the front guide surface, or when the input surface is on the rear side of the waveguide, the input surface extends parallel to the rear guide surface.

49. A deformable near-eye display device according to claim 48, wherein when the input surface is on the front side of the extraction waveguide, the input surface is coplanar with the front guide surface, or when the input surface is on the rear side of the waveguide, the input surface is coplanar with the rear guide surface.

50. The anamorphic near-eye display device of any one of claims 46 to 48, wherein the input surface is disposed outside one of the front guide surface or the rear guide surface.

51. The anamorphic near-eye display device of claim 50, wherein the input section further comprises a separation surface extending outwardly from one of the front guide surface or the rear guide surface to the input surface.

52. A morphing near-eye display device according to any one of claims 44 to 51, wherein the input section is integral with the extraction waveguide.

53. A deformable near-eye display device according to any one of claims 44 to 51, wherein The extraction waveguide has an end that is an input face, the extraction waveguide being arranged to receive light from the illumination system through the input face, and The input section is a separate element from the extraction waveguide, the separate element further comprising an output face and arranged to guide light reflected by the input reflector through the output face and into the extraction waveguide through the input face of the extraction waveguide.

54. A deformable near-eye display device according to any of the preceding claims, wherein the pixels of the spatial light modulator are also distributed in the lateral direction so that light output from the lateral deformable component is guided in a direction distributed in the lateral direction.

55. A deformable near-eye display device according to any one of claims 1 to 53, wherein the illumination system further comprises a deflector element arranged to deflect light output from the lateral deformable component by a selectable amount, the deflector element being selectively operable to direct light output from the lateral deformable component into a direction distributed in the lateral direction.

56. A deformable near-eye display device according to any of the preceding claims, wherein the spatial light modulator comprises pixels having spacings in the lateral direction and the transverse direction, the ratio of the spacings being the same as the inverse of the ratio of the optical focal lengths of the lateral deformable optical element and the transverse deformable optical element.

57. A deformable near-eye display device according to any preceding claim, further comprising a control system arranged to operate the illumination system to provide light input in accordance with image data representing an image.

58. A head-mounted display device, comprising a deformable near-eye display device according to any one of the preceding claims and a head fixing arrangement, wherein the head fixing arrangement is arranged to fix the deformable near-eye display device on the head of a wearer, wherein the deformable near-eye display device extends across at least one eye of the wearer.

59. A head mounted display device according to claim 58, the head mounted display device further comprising lenses having optical power, the deformable near eye display device overlying one or each lens.

60. A head mounted display device according to claim 58 or 59, wherein the head mounted display device comprises a pair of glasses.

61. A deformable directional lighting device, the deformable directional lighting device comprising: a lighting system comprising an array of light sources, the lighting system being arranged to output light; as well as An optical system arranged to guide light from the illumination system, wherein the optical system has an optical axis and has an anamorphic property in a lateral direction and a transverse direction perpendicular to each other and perpendicular to the optical axis, wherein the light source array comprises light sources distributed in the lateral direction, and the optical system comprises: a transverse anamorphic component having positive optical power in the transverse direction, wherein the transverse anamorphic component is arranged to receive light from the array of light sources, and the illumination system is arranged so that light output from the transverse anamorphic component is directed in directions distributed in the transverse direction; an extraction waveguide arranged to receive light from the lateral deformation component; a lateral anamorphic component having positive optical power in the lateral direction, the extraction waveguide being arranged to guide light from the lateral anamorphic component along the extraction waveguide to the lateral anamorphic component in a first direction; and a light retro-reflector arranged to reflect light directed along the extraction waveguide in the first direction to form light directed along the extraction waveguide in a second direction opposite to the first direction, in: The extraction waveguide comprises: front guide surface; a polarization-sensitive reflector opposite the front directing surface; and an extraction element disposed outside the polarization-sensitive reflector, The extraction element comprises: a rear guide surface, the rear guide surface being opposite to the front guide surface; and at least one extracted feature; The anamorphic directional illumination device is arranged to provide an input linear polarization state to light guided along the extraction waveguide in the first direction before the light reaches the polarization-sensitive reflector; and The optical system further comprises a polarization conversion retarder disposed between the polarization-sensitive reflector and the light retro-reflector, wherein the polarization conversion retarder is arranged to convert the polarization state of light passing through the polarization conversion retarder between a linear polarization state and a circular polarization state, and the polarization conversion retarder and the light retro-reflector are arranged in combination to rotate an input linear polarization state of light directed in the first direction so that light directed in the second direction and output from the polarization conversion retarder has an orthogonal linear polarization state orthogonal to the input linear polarization state; the polarization-sensitive reflector being arranged to reflect light having the input linear polarization state directed in the first direction and to pass light having the orthogonal linear polarization state directed in the second direction, such that the front guiding surface and the polarization-sensitive reflector are arranged to guide light in the first direction, and the front guiding surface and the rear guiding surface are arranged to guide light in the second direction; and The at least one extraction feature is arranged to extract light guided along the extraction waveguide in the second direction through the front guide surface.

62. A vehicle exterior lamp device, comprising the deformed directional lighting device according to claim 61.

63. A vehicle exterior light device, the vehicle exterior light device comprising: a housing for mounting on a vehicle; as well as According to the vehicle exterior light device according to claim 62, the vehicle exterior light device is mounted on the housing.

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