Novel waveguide systems for near-eye displays

Abstract

A waveguide system for a near-eye display may include a first waveguide section and a second waveguide section. The first waveguide section may include a first set of at least partially reflective surfaces configured to coupled output light corresponding to an image from the first waveguide section so as to extend the aperture to a first dimension. The second waveguide section may include a second set of partially reflective surfaces positioned beside the first waveguide section and configured to receive light from the first waveguide section and to coupled output light corresponding to an image so as to extend the aperture to a second dimension non-parallel to the first dimension.

Description

Technical Field

[0001] The present disclosure relates to the field of near-eye display systems such as head-mounted displays. More particularly, the present disclosure relates to a compact waveguide system designed for near-eye displays (NEDs).

Background Art

[0002] Consumer demand for improved human-computer interfaces has increased interest in high-quality image head-mounted displays (HMDs) or near-eye displays (NEDs), commonly known as smart glasses. These devices can provide virtual reality (VR) or augmented reality (AR) experiences and improve the way users interact with digital content and their surrounding environment.

[0003] When using an HMD, consumers seek better image quality, immersive experiences, and higher comfort. Consumers expect displays that are high-resolution, have vivid colors, minimal distortion, and create a realistic and enjoyable viewing experience. Additionally, comfort is an important factor as users often wear these devices for long periods. Consumers desire a lightweight and sophisticated design that is not overly obtrusive to wear and is more convenient in various scenarios. Also, miniaturization of the device improves portability and makes it easier to carry and use in different environments. Therefore, there is an increasing demand for higher-performance yet smaller and more compact HMDs.

[0004] A key element in conventional near-eye display systems is the waveguide. The waveguide is the device that guides light from the system image projector to the user's eyes. The waveguide relies on total internal reflection along the main surface within the device to propagate light. There are inherent limitations to the miniaturization of waveguides, which in turn limit the miniaturization of head-mounted displays. For example, conventional features that support more efficient waveguide illumination tend to increase the size of the waveguide. In another example, conventional features that support waveguide miniaturization tend to degrade the image quality or visual appeal of the near-eye display system.

[0005] Another important element of near-eye display systems is the projector. In the context of HMDs and NEDs, an image projector is a device that generates visual content and projects it onto an intermediate medium (i.e., a waveguide) to reach the eyes. Its purpose is to provide the user with the perception of an image or video, often to create the illusion of depth or three-dimensionality. Conventional projectors did not contribute to the miniaturization that is the goal of HMDs.

[0006] Therefore, there is a need for a compact waveguide system that contributes to the miniaturization of NEDs, as well as an innovative compact lighting system including a novel projector. [Overview of the project]

[0007] This disclosure relates to the use of reflective elements to reduce the size of waveguide systems. In one embodiment, the reflective element makes it possible to fold the interface between the first waveguide section (HLOE) and the second waveguide section (LOE) in the waveguide system, thereby reducing its overall size. In another embodiment, the reflective element makes it possible to introduce an illumination enhancement element hidden within the frame of a near-eye display.

[0008] Furthermore, this disclosure also covers projector designs that enable miniaturization of waveguide elements by selectively and efficiently projecting a light beam corresponding to the projected image.

[0009] The accompanying drawings incorporated herein and constituting part thereof illustrate various exemplary systems, methods, etc., illustrating various exemplary embodiments of aspects of the present invention. It will be understood that the boundaries of elements shown in the drawings (e.g., boxes, groups of boxes, or other shapes) represent examples of boundaries. Those skilled in the art will understand that one element may be designed as multiple elements, or multiple elements may be designed as one element. An element shown as an internal component of another element may be implemented as an external component, and vice versa. Furthermore, elements may not be drawn to scale. [Brief explanation of the drawing]

[0010] [Figure 1A] This figure shows an example of a near-eye display (NED). [Figure 1B] This diagram schematically illustrates the concept of two-dimensional aperture expansion (aperture doubling) in NED. [Figure 2] This figure shows a novel waveguide system for NED. [Figure 3] This figure shows a novel waveguide system for NED. [Figure 4] This figure shows a novel waveguide system for NED. [Figure 5] This figure shows a waveguide system for two-dimensional aperture expansion. [Figure 6A] This figure shows an alternative waveguide system for 2D aperture expansion. [Figure 6B] This figure shows an alternative waveguide system for 2D aperture expansion. [Figure 6C] This figure shows an alternative waveguide system for 2D aperture expansion. [Figure 7] This is a schematic diagram of an exemplary projector for controlling the light beam distribution in the projector aperture. [Figure 8A] This is a schematic diagram of another exemplary projector for controlling the light beam distribution in the projector aperture. [Figure 8B] This is a schematic diagram of another exemplary projector, corresponding to the projector in Figure 8A, but using LCOS technology and a polarizing beam splitter (PBS). [Figure 9A] This is a schematic diagram of another exemplary projector designed to control the light beam distribution in the projector aperture. [Figure 9B] This is a schematic diagram of another exemplary projector that corresponds to the projector in Figure 9A, but uses LCOS technology and a polarizing beam splitter (PBS). [Figure 10A] A schematic diagram of another exemplary projector for controlling the light beam distribution in the projector aperture is shown. [Figure 10B] This is a schematic diagram of another exemplary projector that uses a polarizing beam splitter (PBS), corresponding to the projector in Figure 10A. [Figure 11] This figure shows an alternative waveguide system similar to the system in Figure 5, but modified so that the waveplate is located at the edge of the waveguide system. [Figure 12] Figure 12A shows an alternative waveguide system similar to the system in Figure 11A, but modified to include at least one modified partial reflector. Figure 12B is a close-up of the first alternative to the system in Figure 12A. [Figure 13A] This figure shows a waveguide system corresponding to the configuration in Figure 12A. [Figure 13B] This figure shows a waveguide system corresponding to the configuration in Figure 12A. [Figure 13C] This figure shows a waveguide system corresponding to the configuration in Figure 12A. [Figure 14] This figure shows an exemplary manufacturing process for constructing a system like the one shown in Figure 12A. [Figure 15] This figure shows a waveguide system similar to the system in Figure 12A, but here the reflecting surfaces are segmented as parallel reflecting surfaces. [Figure 16] This figure shows a waveguide system that combines the features of the system in Figure 6 and the system in Figure 12A.

Embodiments for Carrying Out the Invention

[0011] Certain embodiments of the present invention provide an optical system and a light projection system for achieving optical aperture expansion for the purpose of a near-eye display, such as a head-mounted display (HMD) or a near-eye display, which may generally be known as smart glasses, for example, a virtual reality display or an augmented reality display. Consumers' demands for a better and more comfortable human-computer interface have stimulated the demands for better image quality and smaller devices.

[0012] An exemplary embodiment of a device in the form of a near-eye display according to the teachings of an embodiment of the present invention, generally indicated at 1 and using a waveguide system 10, is schematically shown in FIG. 1A. The near-eye display (NED) 1 uses a compact image projector (or “POD”) 12 optically coupled to inject an image into a waveguide system (alternatively referred to as a “substrate” or “slab”) 10, within which the image light is confined in one dimension by internal reflection at a set of flat outer surfaces parallel to each other.

[0013] Optical aperture expansion is achieved within the waveguide system 10 by one or more devices for gradually redirecting image illumination, which typically use a set of partially reflective surfaces (alternatively referred to as “facets”) that are parallel to each other and may be inclined obliquely with respect to the propagation direction of the image light, and each successive facet deflects a portion of the image light in a deflection direction. As shown in FIG. 1A, the two-dimensional aperture expansion is achieved using a first waveguide section 14 that transmits light along the X direction and a set of first facets within the waveguide section 14 for gradually redirecting the image illumination within the waveguide system 10 in the Y direction, and this image illumination is also confined / guided by internal reflection.

[0014] Next, the deflected image illumination enters a second waveguide section 16, which may be implemented as adjacent separate substrates or as a continuous single substrate, and a coupled output device (e.g., an additional set of partial reflection facets) progressively coupled a portion of the image illumination in the Z direction toward the observer's eye located within the section defined as an eye motion box (EMB), thereby achieving two-dimensional optical aperture expansion. Similar functionality can be obtained using diffractive optical elements (DOEs) for redirection and / or coupled output of the image illumination within one or both of sections 14 and 16.

[0015] The entire device may be implemented separately for each eye, preferably supported against the user's head with each waveguide system 10 directed towards the user's corresponding eye. In one particularly preferred option shown here, the support device is implemented as a spectacle frame 18 having sides for supporting the device against the user's ears. Other forms of support devices may be used, but are not limited to these, such as a headband, visor, or device suspended from a helmet.

[0016] In this specification, in the drawings and claims, the X-axis extends horizontally (or, in an alternative embodiment, vertically) in the overall extension direction of the first section 14 of the waveguide system 10, the Y-axis is perpendicular to it, i.e., vertically (or, in an alternative embodiment, horizontally) in Figure 1A, and the Z-axis is perpendicular to these, i.e., horizontally toward the user's eye. Very broadly speaking, the first section 14 of the waveguide system 10 may be considered to achieve aperture expansion in the X-direction, while the second section 16 of the waveguide system 10 achieves aperture expansion in the Y-direction. Details of the angular spread in which different parts of the field of view propagate will be described more precisely below. The orientation shown in Figure 1A may be considered a “top-down” embodiment, where the image illumination entering the second section 16 of the waveguide system 10 enters from the top edge, while the alternative orientation may be considered a “side-injection” embodiment, where it should be noted that the axis referred to as the Y-axis is horizontally positioned.

[0017] In the remaining drawings, similar to Figure 1A, various features of a particular embodiment of the present invention are shown in a “top-down” orientation context. However, it should be understood that all of these features are equally applicable to side-injection embodiments, and these are also included within the scope of the invention. In specific cases, other intermediate orientations are also applicable and are included within the scope of the invention unless explicitly excluded. While the two-dimensional expansion embodiments shown herein are merely illustrative, the present invention is also applicable to embodiments in which only single-dimensional aperture expansion is performed by the waveguide system 10.

[0018] The near-eye display 1 will be understood to include various additional components, typically including a controller 19 for operating the image projector 12, and typically using power from a small onboard battery (not shown) or some other suitable power source. The controller 19 will be understood to include all necessary electronic components, such as at least one processor or processing circuit, for driving the image projector 12.

[0019] Large-field waveguides for NEDs, such as waveguide system 10, require a large surface area that is not always ergonomically feasible. Figure 1B schematically illustrates the concept of two-dimensional aperture expansion (aperture doubling) in NEDs. An image projector 12 projects a collimated light beam representing an image at infinity (the two arrows represent the light beams at the edges of the image). Light from the projector 12 enters the waveguide system 10 and propagates by total internal reflection (TIR) ​​in one dimension and diverging in the other dimension (different beams diverging from different parts of the image). The beam propagates through the waveguide system 10, specifically the first section 14 (also called HLOE), by total internal reflection, as shown in the top view of Figure 1B(a). The beam enters the embedded partial reflector 14a of the first section 14, as shown in the front view of Figure 1B(b), and is redirected toward the partial reflector 16a of the second section 16 (also called the LOE), which reflects the beam from the waveguide system 10 toward the observer or the eye-motion box (EMB) 17, as shown in the side view of Figure 1B(c).

[0020] Partial reflectors 14a and 16a increase the aperture in the transverse and longitudinal directions, respectively. The length, position, and spacing of facets 14a and 16a may be varied to achieve an optimal and uniform projected image (shown as the same distance for clarity). Facets 14a and 16a may be perpendicular or oblique to the outer surfaces of HLOE 14 and LOE 16, respectively. To improve reflectivity, a waveplate may be introduced between HLOE 14 and LOE 16. For better image uniformity, a longitudinal partial reflector (homogenizer) may be introduced before HLOE 14 (improved light injection) or after HLOE 14.

[0021] Solutions for 2D extensions utilizing the aforementioned HLOE and LOE are commercially available from Lumus Ltd. (Israel), and details of such waveguide systems can be found, for example, in International Publication No. 2020 / 049542, owned by the same applicant.

[0022] The waveguide system 10 in Figures 1A and 1B has a relatively large height (Y) dimension, which in turn makes the corresponding NED 1 relatively large and bulky. However, NED users are seeking greater comfort. Comfort is an important factor because users often wear these devices for extended periods. Consumers want a lightweight, sophisticated design that is less conspicuous to wear, more convenient, and suitable for various scenarios. Furthermore, miniaturization of the device improves portability, making it easier to carry and use in various environments. Therefore, there is a growing demand for smaller and more compact NEDs. Miniaturization of the waveguide enables smaller and more comfortable NEDs. However, conventionally, there have been limitations to waveguide miniaturization, which in turn limits the miniaturization of NEDs.

[0023] Figure 2 shows a novel waveguide system 20 for NED1. Figure 2 shows that the first waveguide section 24 of the waveguide system 20 (optically corresponding to the first section 14 of the waveguide system 10 in Figures 1A and 1B) can be folded to achieve an ergonomic configuration. The first waveguide section 24 has an aperture 24c into which a light beam corresponding to an image from the image projector 12 enters the waveguide system 20. In the first waveguide section 24, the light beam propagates in a first dimension (e.g., X) and a second dimension (e.g., Z) that is non-parallel to the first dimension (e.g., orthogonal). The first waveguide section 24 guides the light to the Y dimension by total internal reflection.

[0024] The first section 24 includes a redirection component 24b (e.g., a folding mirror) at its end that redirects the light beam toward a partial reflector 24a to propagate in a third dimension (e.g., Y) that is non-parallel (e.g., orthogonal) to the first dimension (e.g., X) and the second dimension (e.g., Z). The partial reflector 24a expands the aperture to the first dimension (e.g., X) and redirects the beam toward the partial reflector 26a of the second section 26. The second waveguide section 26 receives the light beam and propagates it toward the third dimension (e.g., Y). The second waveguide section 26 guides the light toward the Z dimension by total internal reflection. A second set of partially reflective surfaces 26a combines and outputs an image toward the second dimension (e.g., Z) to expand the aperture toward the third dimension (e.g., Y).

[0025] In this configuration, the height (Y) of the waveguide system 20 is significantly lower than the height (Y) of the waveguide system 10, the triangular shape of the first section 24 fits the edge of the NED 1, and there is space (in the Z dimension) between the waveguide system 20 and the user's face. The angle between section 24 and section 26 may vary depending on ergonomic requirements and optical optimization. Depending on the angle between sections 24 and 26, the reflector 24b may be replaced with a prism. The thicknesses of the guide sections 24 and 26 may differ from each other. In one embodiment, the first section 24 is thicker than the second section 26 so that section 26 can be illuminated better.

[0026] Figure 3 shows a novel waveguide system 30 for NED1. Figure 3 shows a more compact configuration (in the height Y dimension) than system 20 in Figure 2. In system 30, the partial reflector 34a is positioned above the fold (rather than below the fold, as in system 20 in Figure 2) and acts to redirect the beam in a similar manner to system 20 in Figure 2.

[0027] The first waveguide section 34 has an aperture 34c into which a light beam corresponding to an image from the image projector 12 enters the waveguide system 30. In the first waveguide section 34, the light beam propagates in a first dimension (e.g., X) and a second dimension (e.g., Z) that is non-parallel to (e.g., orthogonal to) the first dimension. The first waveguide section 34 guides the light into the Y dimension by total internal reflection. The first waveguide section 34 also has a partial reflector 34a that extends the aperture into the first dimension (e.g., X). At its end, the first section 34 includes a redirection component 34b (e.g., a folding mirror) that redirects the light beam toward the second waveguide section 36 to propagate in a third dimension (e.g., Y) that is non-parallel to (e.g., orthogonal to) the first dimension (e.g., X) and the second dimension (e.g., Z). The second waveguide section 36 receives the light beam and propagates it into a third dimension (e.g., Y). The second waveguide section 36 guides the light into the Z dimension by total internal reflection. The second waveguide section 36 has a partial reflector 36a that combines and outputs the image to the second dimension (e.g., Z) so as to extend the aperture into the third dimension (e.g., Y).

[0028] In this configuration, the height (Y) of the waveguide system 30 is significantly lower than the height (Y) of the waveguide system 10, the triangular shape of the first section 34 fits the edge of the NED 1, and there is space (in the Z dimension) between the waveguide system 30 and the user's face. The angle between section 34 and section 36 may vary depending on ergonomic requirements and optical optimization. Depending on the angle between sections 34 and 36, the reflector 34b may be replaced with a prism. The thicknesses of the guide sections 34 and 36 may differ from each other. In one embodiment, the first section 34 is thicker than the second section 36 so that section 36 can be illuminated better.

[0029] In one embodiment, the prism-supporting mirror 34b may have an interface 33a with HLOE 34 and an interface 33b with LOE 36. One or both of these interfaces may have a low refractive index with respect to their respective waveguides or air gaps. This type of interface can reduce losses and improve coupling between HLOE 34 and LOE 36.

[0030] Figure 4 shows a novel waveguide system 40 for NED1. Figure 4 shows a more compact configuration (in the height Y dimension) than system 10 in Figure 1. The HLOE partial reflectors 44a are set at an oblique angle to waveguide sections 44 and 46. These HLOE partial reflectors 44a are located at the interface between sections 44 and 46 and serve both to reflect the light beam from waveguide section 44 to waveguide section 46 and to partially transmit (partially reflect) the light beam for lateral (X dimension) extension. Thus, here the oblique HLOE facets 44a serve to perform both functions as performed by the partial reflectors 24a, 34a and reflective components 24b, 34b in Figures 2 and 3, respectively.

[0031] The first waveguide section 44 has an aperture 44c into which a light beam corresponding to an image from the image projector 12 enters the waveguide system 40. In the first waveguide section 44, the light beam propagates in a first dimension (e.g., X) and a second dimension (e.g., Z) that is non-parallel to (e.g., orthogonal to) the first dimension. The first waveguide section 44 guides the light to the Y dimension by total internal reflection. A partial reflector 44a extends the aperture to the first dimension (e.g., X). The partial reflector 44a also redirects the light beam toward the second waveguide section 46 toward a third dimension (e.g., Y) that is non-parallel to (e.g., orthogonal to) the first dimension (e.g., X) and the second dimension (e.g., Z). The second waveguide section 46 receives the light beam and propagates it toward the third dimension (e.g., Y). The second waveguide section 46 guides light into the Z dimension by total internal reflection. The second waveguide section 46 has a partial reflector 46a that combines the image into the second dimension (e.g., Z) to extend the aperture into a third dimension (e.g., Y).

[0032] In this configuration, the height (Y) of the waveguide system 40 is significantly lower than the height (Y) of the waveguide system 10, the triangular shape of the first section 44 fits the edge of the NED 1, and there is space (in the Z dimension) between the waveguide system 40 and the user's face. The angles of the facets 44a may vary depending on ergonomic requirements and optical optimization. The thicknesses of the guide sections 44 and 46 may differ from each other. In one embodiment, the first section 44 is thicker than the second section 46 so that section 46 can be better illuminated.

[0033] Figure 5 shows a waveguide system 50 for two-dimensional aperture expansion in a 1D waveguide. Here, three beams are drawn: a solid arrow representing the center of the field of view, a dashed arrow representing a ray on one edge of the field of view, and a dashed-dotted arrow representing a ray on the opposite edge of the field of view. All field rays may be injected into the waveguide system 50 through a single narrow pupil or aperture 54c. Thus, the aperture of the projector 12 (not shown) in this plane can have a relatively small aperture corresponding to aperture 54c. As the beam propagates through the HLOE 54, some of the light is reflected downward by facet 54a toward the LOE 56 and its facet 56a. The first edge reflection (dashed-dotted line) is reflected at 54aa near aperture 54c, while the center ray (solid arrow) is reflected at 54ab, and the other edge of the image is reflected at 54ac (dashed line).

[0034] A potential problem with this configuration is that it requires a relatively large HLOE section 54 (with facet 54a) which is not ergonomically optimal for use in NED embodiments.

[0035] Figure 6A shows an alternative waveguide system 60a, which differs from system 50 in Figure 5, in that the optical beams do not enter the waveguide from the same point. In this configuration, both lateral image beams enter the waveguide from point 12a, and the central image beam enters the waveguide from point 12b. As a result, the projector aperture 64c is widened to project all beams that produce the entire image. In this configuration, the HLOE facet 64a reflects the beam, but from different points 64aa, 64ab, and 64ac. The new arrangement of reflection points allows for a much smaller layout of the HLOE 64, which may be ergonomically acceptable for NED embodiments.

[0036] Waveguide system 60a has a first waveguide section 64 and a second waveguide section 66. Although this disclosure refers to the first waveguide section 64 and the second waveguide section 66 as separate sections, these waveguide sections may be implemented as part of a single waveguide or waveguide assembly. See, for example, Figure 11C.

[0037] The first waveguide section 64 has an aperture 64c into which a light beam corresponding to an image from an image projector (not shown) enters the waveguide system 60a.

[0038] The first waveguide section 64 includes a first set of at least partially reflective surfaces 64a. The first set of at least partially reflective surfaces 64a combines and outputs light corresponding to the image from the first waveguide section 64 so as to extend the aperture to a first dimension (e.g., X).

[0039] The second waveguide section 66 includes a second set of partially reflective surfaces 66a that receive light from the first waveguide section 64 and combine and output light corresponding to the image so as to extend the aperture to a second dimension (e.g., Y) that is non-parallel (e.g., orthogonal) to the first dimension (e.g., X).

[0040] As shown in Figure 6A, the first outermost light beam (corresponding to pixels on the edge of the image) is at least partially reflected by the first outermost at least partially reflective surface 64aa. The second outermost light beam (corresponding to pixels on the opposite edge of the image) is at least partially reflected by the second outermost at least partially reflective surface 64ac located at the opposite end of waveguide section 64. The central light beam (corresponding to pixels in the center of the image) is at least partially reflected by the third at least partially reflective surface 64ab located between the first and second outermost at least partially reflective surfaces 64aa and 64ab. The first set of at least partially reflective surfaces 64a combines and outputs the light corresponding to the image from the first waveguide section 64 to the second waveguide section 66.

[0041] The facet section 64g schematically shows that the spacing between facets 64a may vary along the HLOE 64 depending on the corresponding illumination aperture. The larger the aperture 64c, the greater the required spacing between facets 64a.

[0042] Figure 6B corresponds to system 60a in Figure 6A, but shows an alternative waveguide system 60b in which the input image light from the projector 12 is coupled to a preliminary waveguide 68. Waveguide 68 (which can perform double or triple light guiding) performs preliminary aperture expansion to match the expanded width of the aperture 64c of the HLOE 64. The preliminary waveguide 68 has internal partial reflective facets 68a that receive the image light from the projector 12 and perform preliminary aperture expansion to match the width of the aperture 64c.

[0043] The partial reflection facets 68a of the waveguide 68 may be designed so that the aperture illumination illuminating a section of the HLOE 64 can vary from section to section. For example, illumination from the edges (64ad or 64ae) may have a smaller aperture illumination compared to the central portion of the aperture 64c. Furthermore, the spacing between facets 64a may vary along the HLOE 64 in response to local aperture illumination. Larger aperture illumination requires a larger spacing between corresponding facets 64a.

[0044] Figure 6C shows a configuration 60c equivalent to 60a in Figure 6A, where two adjacent projectors 201a and 201b project an image in two parts instead of one, as shown in 60a. The two juxtaposed projectors 201a and 201b create a practical expanded projection aperture (corresponding to 64c in 60a) where the apertures of all projectors are fully illuminated, and all projectors illuminate different image fields and different sections of waveguide 66. Projector 201a projects a light beam 203 that reflects off 205 on the side of waveguide section 66. The same projector 201a projects the beam 207a (and the beam between them, not shown for clarity) reflected off waveguide section 64 into a beam 209 at the center of the field of view.

[0045] Projector 201b projects beam 211, which is reflected to become beam 213, and then projects beam 207b (parallel to beam 207a), which is reflected to become beam 209, so that it overlaps with beam 209 originating from beam 207a from projector 201a. Projector 201b also projects the beam between beam 209 and beam 213, thereby partially overlapping with projector 201a and projecting the other half of the field of view.

[0046] The facets of waveguide sections 64 and / or 66 in the above configuration may be replaced with diffraction gratings having substantially the same orientation. The extended input aperture (as described above) may include input coupling with a reflector, prism, or diffracting element.

[0047] As shown in Figure 6C, using two or more projectors 201a, 201b allows for the use of smaller, more easily manufactured, uniformly illuminated miniature projectors while still benefiting from a larger aperture with smaller waveguide sections 64. If multiple projectors are not desired, the light beam distribution shown in Figure 6A may require a novel projector.

[0048] Figure 7 shows a schematic diagram of an exemplary projector 72 designed to control the light beam distribution at projector aperture 73. The exemplary projector 72 generates a beam distribution corresponding to aperture 64c in Figure 6A, where the lateral image beam enters the waveguide from point 12a and the central image beam enters the waveguide from point 12b. In Figure 7, the light beams are marked with solid lines relative to the central field of view and dashed lines relative to the field of view edges, as in Figure 6A.

[0049] The image projector 72 may include a projector aperture 73 corresponding to the aperture 64c of the first waveguide section 64. The image projector 72 may also include an image generating matrix 74, such as a micro-LED, OLED, front-lit LCOS, DLP, or LCD, which is illuminated by a light source 78, such as an LED, laser, or scanning laser. The matrix 74 can generate the image to be projected and project a light beam for each pixel. The image projector 72 may also include a collimating lens 76 that receives and collimates the light corresponding to the image generated by the matrix 74. The image projector 72 may also include a phase element 75 positioned between the matrix 74 and the collimating lens 76 to control the light beam distribution in the projector aperture 73. In Figure 7, the phase element 75 is positioned between the matrix 74 and the collimating lens 76 to control the light beam distribution in the projector aperture 73.

[0050] The phase element 75 may be a transparent wafer with a relief pattern formed on it, or a diffractive optical element through which one or more light beams pass. The profile of the phase element 75 is defined to generate the desired beam distribution. One or more light beams corresponding to the central field of view of the image generated by the matrix 74 exit the projector aperture 73 at the edge of the projector aperture 73, and one or more light beams corresponding to the edge field of view of the image generated by the matrix 74 exit the projector aperture 73 at the center of the projector aperture 73. In the context of Figure 6A, this is such that the lateral image beam enters the waveguide from point 12a and the central image beam enters the waveguide from point 12b on aperture 64c.

[0051] In one preferred embodiment, the phase element 75 is positioned close to the matrix 74 so as not to distort the image. The lens 76 collimates the light beam that emerges from the phase element 75 onto the aperture 73.

[0052] Figure 8A shows a schematic diagram of another exemplary projector 82a designed to control the light beam distribution at projector aperture 73. The exemplary projector 82a generates a beam distribution corresponding to aperture 64c in Figure 6A, where the lateral image beam enters the waveguide from point 12a and the central image beam enters the waveguide from point 12b. In Figure 8A, the light beams are marked with solid lines relative to the central field of view and dashed lines relative to the field of view edges, as in Figure 6A.

[0053] The image projector 82a may include a projector aperture 73 corresponding to the aperture 64c of the first waveguide section 64. The image projector 82a may also include an image generation matrix 74 illuminated by a light source 78. The matrix 74 can generate an image to be projected and project a light beam for each pixel. The image projector 82a may also include a collimating lens 76 that receives and collimates the light corresponding to the image generated by the matrix 74. In Figure 8A, the collimating lens 76 is optically positioned between the projector aperture 73 and the matrix 74. The image projector 72a may also include a phase element 75 positioned relative to the matrix 74 and the collimating lens 76 to control the light beam distribution in the projector aperture 73. In Figure 8A, the phase element 75 is optically positioned between the light source 78 and the matrix 74 and controls the light beam distribution in the projector aperture 73. The image projector 72 may also include an optical component 86a optically positioned between the light source 78 and the phase element 75 to optimize the optical power coupling in the projector aperture 73 while minimizing the optical power required by the phase element 75.

[0054] In Figure 8A, the phase element 75 is optically positioned between the light source 78 and the matrix 74, and is located close to the matrix 74. This arrangement may also be applicable to a transparent LCD matrix 74 or LCOS, and the phase element 34 may be a unidirectional active diffuser, such as a polarization-selective diffuser. In other embodiments, the phase element 75 may be located on the other side of the matrix 74, or it may be split on both sides of the matrix 74 (it can also be applied as a simple phase element adjacent to an active LCOS before and after reflection).

[0055] Figure 8B shows a schematic diagram of another exemplary projector 82b, corresponding to projector 82a in Figure 8A, but using LCOS technology and a polarizing beam splitter (PBS) 81. Here, the phase element 75 passes twice, once before and once after being reflected by the LCOS matrix 74, so the phase of each pass is half the required phase.

[0056] Projector 82b includes a projector aperture 73 corresponding to the aperture 64c of the first waveguide section 64 in Figure 6A. Projector 82b also includes a light source 78 and an LCOS matrix 74 optically positioned between the projector aperture 73 and the light source 78. The matrix 74 receives light from the light source 78 and generates a projected image. Projector 82b also includes a phase element 75 optically positioned between the light source 78 and the matrix 74 to control the light beam distribution in the projector aperture 73. Projector 82b also includes a PBS 81 optically positioned between the light source 78 and the projector aperture 73. The PBS 81 reflects first-polarized light from the light source 78 to the matrix 74 via the phase element 75. The matrix 74 changes the polarization of the light. The PBS 81 reflects second-polarized light from the matrix 74 through the phase element 75 to a polarizing reflector 87, thereby changing the polarization of the light again. The first polarized light is reflected from the polarizing reflector 87 to the projector aperture 73. The projector 82b is optically positioned between the light source 78 and the phase element 75 and also includes an optical component 86c that optimizes the optical power coupling at the projector aperture 73 while minimizing the optical power required by the phase element 75.

[0057] Figure 9A shows a schematic diagram of another exemplary projector 92a designed to control the light beam distribution in the projector aperture 73. The exemplary projector 92a generates a beam distribution corresponding to aperture 64c in Figure 6A, where the lateral image beam enters the waveguide from point 12a and the central image beam enters the waveguide from point 12b. In Figure 9A, the light beams are marked with solid lines relative to the central field of view and dashed lines relative to the field of view edges, as in Figure 6A. Projector 92a is an extended configuration required when it is not practical to mount the phase element 75 adjacent to the matrix 74. In such a case, the phase element 75 forms a conjugate relationship with the plane of the matrix 74, and the light source 78 forms a conjugate relationship with the aperture 73.

[0058] Similar to the previous projector, here the light source 78 illuminates the phase element 75 via optical component 86a, and the phase element 75 is imaged onto the matrix 74 via optical component 86b. The image projector 92a may also include a collimating lens 76 that receives and collimates the light corresponding to the image generated by the matrix 74 and transmits the collimated light to the aperture 73.

[0059] The projector 92a may include a projector aperture 73 corresponding to the aperture 64c of the first waveguide section 64. The projector 92a may also include a light source 78 and a matrix 74 optically positioned between the projector aperture 73 and the light source 78. The matrix 74 receives light from the light source 78 and generates a projected image. The projector 92a may also include a collimating lens 76 optically positioned between the projector aperture 73 and the matrix 74. The lens 76 can receive and collimate light corresponding to the image generated by the matrix 74. The projector 92a may also include a phase element 75 optically positioned between the light source 78 and the matrix 74 to control the light beam distribution in the projector aperture 73. The projector 92a may also include optical components 86a and 86b optically positioned between the light source 78 and the phase element 75, and between the phase element 75 and the matrix 74, respectively. Optical components 86a and 86b optimize optical power coupling in the projector aperture 73 while minimizing the optical power required by the phase element 75.

[0060] Figure 9B shows a schematic diagram of another exemplary projector 92b, which corresponds to projector 92a in Figure 9A, but uses LCOS technology and a polarizing beam splitter (PBS) 81. The phase element 75 passes twice, once before and once after being reflected by the LCOS matrix 74, so the phase of each pass is half the required phase.

[0061] The projector 92b may include a projector aperture 73 corresponding to the aperture 64c of the first waveguide section 64, a light source 78, and a matrix 74 optically positioned between the projector aperture 73 and the light source 78. The matrix 74 receives light from the light source 78 and generates a projected image. The projector 92a may also include a phase element 75 optically positioned between the light source 78 and the matrix 74 to control the light beam distribution in the projector aperture 73. The projector 92a may also include a PBS 81 optically positioned between the light source 78 and the projector aperture 73, which reflects first-polarized light from the light source 78 to the matrix 74 via the phase element 75, reflects second-polarized light from the matrix 74 to a polarizing reflector 87, and reflects first-polarized light from the polarizing reflector 87 to the projector aperture 73. The projector 92a also includes an optical component 87a optically positioned between the light source 78 and the phase element 75, and an optical component 87b positioned between the phase element 75 and the matrix 74, which can optimize the optical power coupling in the projector aperture 73 while minimizing the optical power required by the phase element 75.

[0062] Alternatively, each reflective pixel element on the LCOS is generated with a slope that matches the required local phase. For example, if the reflected beam from one of the pixels in the LCOS needs to exit from the side of the aperture, the reflective element for that pixel in the LCOS is generated. On the other hand, if the beam needs to exit from the center of the aperture, the reflective element in the LCOS matrix may be flat.

[0063] Figure 10A shows a schematic diagram of another exemplary projector 102a designed to control the light beam distribution in the projector aperture 73. The exemplary projector 102a generates a beam distribution corresponding to aperture 64c in Figure 6A, where the side image beam is incident on the waveguide from point 12a and the central image beam is incident on the waveguide from point 12b. In Figure 10A, the light beams are marked with solid lines relative to the central field of view and dashed lines relative to the field of view edges, as in Figure 6A. In projector 102a, each reflective pixel element on the LCOS matrix 74a is generated with a tilt that conforms to the required local phase. For example, if a reflected beam from one of the pixels in the LCOS matrix 74a needs to exit from the side of aperture 73, the reflective element for this pixel in the LCOS matrix 74a is generated with a tilt in the direction indicated by arrow 74c. On the other hand, if that beam needs to exit from the center of aperture 73, the reflective element in the LCOS matrix 74a is flat.

[0064] The projector 102a may include a projector aperture 73 corresponding to the aperture 64c of the first waveguide section 64, a light source 78, and an LCOS matrix 74a optically positioned between the projector aperture 73 and the light source 78. The matrix 74a receives light from the light source 78 and generates a projected image. Each reflective pixel element on the matrix 74a is set to its respective tilt (in the direction indicated by arrow 74c) to control the light beam distribution in the projector aperture 73.

[0065] Here, "tilt" refers to the change in the orientation of liquid crystal molecules in the LCOS matrix that adjusts the polarization of the reflected light. By adjusting the electric field applied to each pixel, the light intensity of each pixel can be modulated. This controls the light pattern that forms the image, controlling which pixels are bright and which are dark, and effectively setting each reflective pixel element to its respective tilt to control the light beam distribution in the projector aperture 73. Therefore, the light distribution in the projector aperture 73 may be controlled by manipulating the polarization of the light reflected from each pixel in the matrix 74a. The lens 76 can receive and collimate the light corresponding to the image generated by the matrix 74a.

[0066] Each reflective pixel element on the matrix 74a may be set to a tilt such that one or more light beams corresponding to the central field of view of the image exit the projector aperture 73 at the edge of the projector aperture 73. Similarly, each reflective pixel element on the matrix 74a may be set to a tilt such that one or more light beams corresponding to the edge field of view of the image exit the projector aperture 73 at the center of the projector aperture 73.

[0067] Figure 10B shows a schematic diagram of another exemplary projector 102b, which corresponds to projector 102a in Figure 10A, but uses a polarizing beam splitter (PBS) 81. The exemplary projector 102b generates a beam distribution corresponding to aperture 64c in Figure 6A, where the side image beam enters the waveguide from point 12a and the central image beam enters the waveguide from point 12b. In projector 102b, as described above, each reflective pixel element on the LCOS matrix 74a is generated with a slope that conforms to the required local phase. If the reflected beam from one of the pixels in the LCOS matrix 74a needs to exit from the side of aperture 73, a reflective element for that pixel in the LCOS matrix 74a is generated. Conversely, if the beam needs to exit from the center of aperture 73, the reflective element in the LCOS matrix 74a is flat.

[0068] The projector 102b may include a projector aperture 73 corresponding to the aperture 64c of the first waveguide section 64, a light source 78, and a matrix 74a optically positioned between the projector aperture 73 and the light source 78. The matrix 74a receives light from the light source 78 and generates a projected image. The projector 102b may also include a PBS 81 optically positioned between the light source 78 and the projector aperture 73, which reflects first-polarized light from the light source 78 to the matrix 74a, second-polarized light from the matrix 74a to a polarizing reflector 87, and first-polarized light from the polarizing reflector 87 to the projector aperture 73. The lens 76 can receive and collimate light corresponding to the image generated by the matrix 74a.

[0069] Each reflective pixel element on the matrix 74a may be set to a tilt such that one or more light beams corresponding to the central field of view of the image exit the projector aperture 73 at the edge of the projector aperture 73. Similarly, each reflective pixel element on the matrix 74a may be set to a tilt such that one or more light beams corresponding to the edge field of view of the image exit the projector aperture 73 at the center of the projector aperture 73.

[0070] The coatings on facets such as facet 54a in Figure 5 may be polarization selective, with S-polarized light partially reflected and P-polarized light mostly transmitted. Therefore, introducing a waveplate between waveguides 54 and 56 may be beneficial, as it would cause the light beam to be incident on facet 54a in S-polarized form. However, the presence of a waveplate at that position between waveguides 54 and 56 is likely to be visible to the user, resulting in undesirable reflections and degrading the quality of the projected image.

[0071] Figures 11A, 11B, and 11C show an alternative waveguide system 110, similar to system 50 in Figure 5, but modified so that the waveplate 112 is located at the edge of the waveguide system 110, thereby preventing undesirable reflections. Waveguide system 110 also includes a reflective surface (e.g., a mirror) 114 for reflecting light back through HLOE 54 to LOE 56. As in Figure 5, three beams are drawn: a solid arrow representing the center of the field of view, a dashed arrow representing a ray on one edge of the field of view, and a dashed-dotted arrow representing a ray on the opposite edge of the field of view. Light from the projector 12 (all field of view rays) may be injected into waveguide system 110 through a single narrow pupil or aperture 54c.

[0072] Here, only beam 118 will be described in detail, but all beams follow the same optical process related to the waveplate 112 and reflector 114. Beam 118a is coupled into system 110 through aperture 54c and propagates along waveguide section 54. At this stage, beam 118 is S-polarized. Beam 118a is incident on facet 54ac (in this case, the last facet of waveguide section 54 is important), and facet 54ac is positioned at an angle to reflect beam 118a away from facet 54ac as beam 118b towards waveplate 112 and reflector 114. That is, facet 54ac (and the rest of facet 54a) is angled to reflect light in the opposite direction to the facets of system 50 in Figure 5.

[0073] In Figure 11B, dots represent S-polarized beams, curved arrows represent circularly polarized beams, and double-headed arrows represent P-polarized beams. Beam 118b reaches the quarter-wave plate 112, which changes the beam's polarization from S-polarized to circularly polarized. After passing through the quarter-wave plate 112, beam 118b is circularly polarized and reflected by the reflective surface 114 (e.g., a dielectric mirror or a metallic mirror) back to waveguide section 54. The reflected beam 118c passes through the quarter-wave plate (e.g., a retarder) 112 again, becoming P-polarized beam 118c.

[0074] The P-polarized beam 118c passes through waveguide section 54 with minimal reflection and enters facet 56a of waveguide section 56. Upon reflection by facet 56a, the polarization of beam 118c becomes S-polarized, and therefore the output reflection is optimal.

[0075] As shown in Figure 11C (perspective view of system 110), the visibility of these elements can be minimized by positioning the reflector 114 and waveplate 112 adjacent to the edge of system 110. For example, these elements 112 and 114 (positioned on the square edge shown in Figure 11C) can be placed within the frame 18 of the NED1 to cover or conceal elements 112 and 114 within the frame 18.

[0076] Therefore, the waveguide system 110 may include a first waveguide section 54 having an aperture 54c into which a light beam corresponding to an image from the image projector 12 enters the waveguide system 110. The first waveguide section 54 includes a first set of at least partially reflective surfaces 54a. The first set of at least partially reflective surfaces 54a couples the light corresponding to the image out of the first waveguide section 54 toward the reflector 114 and / or waveplate 112 toward the second waveguide section 56, so as to extend the aperture to a first dimension (e.g., X).

[0077] The waveguide system 110 may also include a second waveguide section 56 which includes a set of second partially reflective surfaces 56a for receiving light from the first waveguide section 54 and coupled outputting light corresponding to an image, so as to extend the aperture to a second dimension (e.g., Y) that is non-parallel (e.g., orthogonal) to a first dimension (e.g., X).

[0078] The waveguide system 110 may also include a quarter-wave plate 112 and one or more reflectors 114 located on the side of the first waveguide section 54 opposite to the side where the second waveguide section 56 is located, (1) a first set of at least partially reflective surfaces 54a coupled output light corresponding to the image from the first waveguide section 54 to the quarter-wave plate 112 and one or more reflectors 114; (2) the quarter-wave plate 112 rotates the polarization of the light by a quarter wavelength; (3) one or more reflectors 114 reflect the light back through the quarter-wave plate 112; (4) the quarter-wave plate 112 rotates the polarization of the light by a quarter wavelength, for example, to P-polarization; (5) the light travels through the first waveguide section 54 toward the second waveguide section 56.

[0079] Figure 12A and system 120 correspond to system 110 in Figure 11A, but are modified to include at least one modified partial reflector (also called a “homogenizer”) 116. Figure 12B shows a first alternative enlarged view. In the embodiment of Figure 12B, system 120 includes a partially reflective surface 116. In the embodiment of Figure 12C, system 120 includes two partially reflective surfaces 116a and 116b. By using the partially reflective surfaces 116 or 116a, 116b, more uniform illumination of the waveguide system 120 (compared to system 110) can be achieved with a smaller gap between the first partial reflector (116 or 116a) and the reflective surface 114. By implementing one or more partial reflectors 116 within the waveguide system 120 as shown, multiple beams are generated that make the output image more uniform. In Figures 12B and 12C, the partial reflectors 116 or 116a, 116b are positioned between the waveplate 112 and the reflector 114.

[0080] Figure 12B shows how one of the light beams is reflected and the other light beam undergoes the same optical process. The incident beam (S-polarized) is converted to circularly polarized light after passing through the waveplate 112. When this ray enters the partial reflector 116, some is reflected and some is transmitted and reflected by the reflecting surface 114. Multiple reflections follow, generating further beams with reduced intensity. All of these beams are reflected back through the waveplate 112 and emerge as P-polarized light toward facet 56a.

[0081] In some configurations, a waveplate is not required, and only the reflector 114 is present. In some configurations, only the partial reflector 116 and the reflector 114 are present. In all of the above configurations, the HLOE 54 may be located to the side or below the facet 56a of the LOE. The facet 56a is reoriented accordingly (with respect to the HLOE 54) to allow the beam to be coupled out from the waveguide section 56. In some configurations, the partial reflector 116 may be located in the optical path before the waveplate 112, thereby partially P-polarizing and partially S-polarizing the reflection, producing a substantially unpolarized beam. The reflectivity of the partial reflector 116 needs to be numerically optimized to achieve maximum and uniform output from the system 120.

[0082] Figure 13A shows system 120 corresponding to the configuration in Figure 12A. Figure 13A shows the nominal image beam path. On the other hand, Figure 13B shows the undesirable beam path (ghost). Here, beam 118 passes through the facet of HLOE 54, is first reflected at reflection point R by the reflecting surface 114 and partial reflector 116, then reflected by the facet of HLOE 54, and then reflected by the facet of LOE 56, continuing as the nominal beam and ultimately producing the undesirable "ghost" image. The reflection of the "ghost" beam at reflection point R is at a high angle, while the nominal reflection (as in Figure 13A) is at a small angle relative to reflectors 114 and 116. Therefore, as shown in Figure 13C, it is possible to design angle-selective dielectric coatings on reflectors 114 and 116. The dielectric coating is designed to experience the required reflectivity (preferably for both polarizations) at incident angles of 0 to 20 degrees, while not being reflected by reflectors 114 and 116 (i.e., being transmitted instead) at higher angles such as 60 to 80 degrees. As shown in Figure 13B, the system 120 may include a light absorber 119 to absorb any light transmitted by reflector 114 (i.e., "ghosts").

[0083] Figures 14A, 14B, and 14C illustrate exemplary manufacturing processes for constructing a system 120 as shown in Figure 12A. Figure 14A shows a stack 140 including a reflector plate 142, an HLOE stack 144, and an LOE stack 146.

[0084] The reflector plate 142 may include an upper (stacked) reflector 114, a waveplate 112, and a bottom partial reflector 116 of the reflector plate 142. As mentioned above, different orders of these components are possible.

[0085] HLOE stack 144 includes HLOE 54 and transparent section 145. HLOE stack 144 is manufactured by stacking partial reflectors (laminated plates having a partially reflective coating) and slicing the resulting structure into the shape shown in Figure 14A. The HLOE 54 facet may be perpendicular to the outer surface of the waveguide or oblique to the outer surface. Transparent section 145 is added so that the top surface of HLOE stack 144 is parallel to its bottom surface. LOE stack 146 is manufactured from a laminated plate having a partially reflective coating. LOE stack 146 is sliced ​​into the shape shown.

[0086] Figure 14B shows the combined stack (142, 144, 146). This combined stack 140 is sliced ​​on a parallel plane parallel to the reflective surfaces 114 and 116 of the sliced ​​reflective plate 143, which are perpendicular to the facets of LOE56.

[0087] As shown in Figure 14C, the generated slice corresponds to system 120 in Figure 12A. Thus, system 120 may include a plate 143 containing a quarter-wave plate 112, one or more partially reflective surfaces 116, and one or more reflectors 114. The plate 143 may be positioned on the side of the first waveguide section (HLOE) 54 opposite the second waveguide section 56 such that (1) a set of first at least partially reflective surfaces 54a coupled output light corresponding to the image from the first waveguide section 54 toward the plate 143, (2) a quarter-wave plate 112 rotates the polarization of the light by a quarter wavelength, (3) one or more partially reflective surfaces 116 partially transmit and partially reflect the light, (4) one or more reflectors 114 reflect the transmitted light back through one or more partially reflective surfaces 116 and the quarter-wave plate 112, (5) one or more partially reflective surfaces 116 partially transmit and partially reflect the reflected light, (6) a quarter-wave plate 112 further rotates the polarization of the light by a quarter wavelength, and (7) the light travels through the first waveguide section 54 toward the second waveguide section 56.

[0088] Figure 15 shows a waveguide system 150 similar to system 120, but here the reflective surface 114 (and / or plate 143) is segmented as parallel reflective surfaces 114a-e. Segmenting the reflective surface 114 allows for a shorter back reflection 118b (compared to reflection 118b in Figure 12A), and therefore a shorter HLOE 54. Furthermore, this arrangement allows for a more ergonomically and perhaps aesthetically pleasingly nearly rounded NED frame 18. By ensuring that the spacing between facets 54a of the HLOE is small, the effects of discontinuities between reflective segments 114a-e are prevented from being projected onto the image. In addition to the reflective surfaces 114a-e, the quarter plate 112, partial reflector 116, and light absorber 119 may also be segmented along the same segments shown in Figure 15.

[0089] Figures 16A, 16B, and 16C show waveguide system 160, which combines features of system 60a in Figure 6 and system 120 in Figure 12A. System 160 is an embodiment that combines inverted facets 164a and reflecting surface 114 (corresponding to facets 54a and reflecting surface 114 in system 120) with a dispersed / large aperture 164c (corresponding to aperture 64c in system 60a). In this configuration, the position of the beam in aperture 164c is different (almost opposite in the vertical direction) compared to the position of the beam in aperture 64c, but the result is the same. By combining the inverted facets 164a and reflecting surface 114 with the dispersed / large aperture 164c, the width of the HLOE section 164 can be narrowed (facet 164a compared to facet 54a). Furthermore, the length of the HLOE 54 can be shortened because the reflection path 118b at the edge of the field of view is much shorter.

[0090] As a result, a compact waveguide system 160 is obtained that can be used to manufacture smaller NEDs.

[0091] definition The following includes definitions of selected terms used herein. The definitions include various examples or forms of components that fall within the scope of the terms and may be used in embodiments. These examples are not intended to be limiting. Both singular and plural forms of terms may be present within the definitions.

[0092] A “operable connection,” or a connection to which an entity is “operable connected,” is a connection to which signals, physical communications, or logical communications can be transmitted or received. Typically, an operable connection includes a physical interface, an electrical interface, or a data interface, but it should be noted that an operable connection may include any different combination of these or other types of connections sufficient to enable operable control. For example, two entities can be operable connected by being able to communicate signals to each other directly or through one or more intermediate entities such as a processor, operating system, logic, software, or other entities. An operable connection can be created using logical or physical communication channels.

[0093] Wherever the terms “includes” or “including” are used in the detailed description or claims, they are intended to be as inclusive as the term “comprising” is when used as a transitional term in the claims. Furthermore, wherever the term “or” is used in the detailed description or claims (e.g., A or B), it is intended to mean “A or B or both.” If the applicant intends to indicate “A or B only and not both,” the term “A or B only and not both” is used. Thus, the use of the term “or” in this specification is inclusive, not exclusive. See Bryan A. Garner, A Dictionary of Modern Legal Usage 624 (2d. Ed. 1995).

[0094] Illustrative systems, methods, etc., are shown by illustrating examples, which are described in considerable detail; however, it is not the applicant's intention to limit or in any way restrict the scope to such detail. Naturally, for the purpose of illustrating the systems, methods, etc. described herein, it is impossible to describe all possible combinations of components or methodologies. Further advantages and modifications will be readily apparent to those skilled in the art. Thus, the present invention is not limited to the specific details, representative apparatus, and illustrative examples illustrated and described. Accordingly, this application is intended to encompass the changes, modifications, and variations included in the appended claims. Furthermore, the foregoing description is not intended to limit the scope of the present invention. Rather, the scope of the present invention should be determined by the appended claims and their equivalents.

Claims

1. Waveguide system for near-eye displays, A first waveguide section having an aperture into which a light beam corresponding to an image from an image projector enters the waveguide system, and including one or more first optical elements configured to couple and output light corresponding to the image from the first waveguide section so as to extend the aperture to a first dimension, A second waveguide section comprising one or more second optical elements positioned on the first side of the first waveguide section, configured to receive light from the first waveguide section, and configured to coupled output light corresponding to the image so as to extend the aperture to a second dimension nonparallel to the first dimension, One or more reflectors located on the second side of the first waveguide section opposite to the first side, wherein (1) one or more first optical elements coupled and output the light corresponding to the image from the first waveguide section toward the one or more reflectors, and (2) one or more reflectors reflected the light corresponding to the image through the first waveguide section toward the second waveguide section, A waveguide system equipped with the following features.

2. The waveguide system according to claim 1, wherein one or more first optical elements correspond to a first set of parallel partially reflective surfaces or a first diffraction grating, and one or more second optical elements correspond to a second set of parallel partially reflective surfaces or a second diffraction grating.

3. A plate comprising a quarter-wave plate and one or more reflectors, wherein (1) the one or more first optical elements coupled and output the light corresponding to the image from the first waveguide section toward the plate, (2) the quarter-wave plate rotated the polarization of the light by a quarter wavelength, (3) the one or more reflectors reflected the transmitted light back through the quarter-wave plate, (4) the quarter-wave plate rotated the polarization of the light by a further quarter wavelength, and (5) the light travels through the first waveguide section toward the second waveguide section. A waveguide system according to claim 1, including the following:

4. Waveguide system according to claim 1, wherein one or more first optical elements correspond to a first set of at least partially reflective surfaces, and one or more second optical elements correspond to a second set of at least partially reflective surfaces, and (1) the first outermost light beam of the light beam is at least partially reflected by the first outermost at least partially reflective surface of the first set of at least partially reflective surfaces, (2) the second outermost light beam of the light beam, opposite to the first outermost light beam, is at least partially reflected by the second outermost at least partially reflective surface of the first set of at least partially reflective surfaces, opposite to the first outermost at least partially reflective surface, and (3) the central light beam of the light beam is at least partially reflected by a third at least partially reflective surface of the first set of at least partially reflective surfaces, positioned between the first outermost at least partially reflective surface and the second outermost at least partially reflective surface.

5. A quarter-wave plate optically positioned between the first waveguide section and one or more reflectors, wherein (1) the one or more first optical elements coupled and output the light corresponding to the image from the first waveguide section toward the quarter-wave plate and the one or more reflectors, (2) the quarter-wave plate rotated the polarization of the light by a quarter wavelength, (3) the one or more reflectors reflected the light back through the quarter-wave plate, (4) the quarter-wave plate further rotated the polarization of the light by a quarter wavelength, and (5) the light traveled through the first waveguide section toward the second waveguide section. The waveguide system according to claim 1, comprising:

6. A plate comprising a quarter-wave plate, one or more partially reflective surfaces, and one or more reflectors, wherein (1) one or more first optical elements coupled and output the light corresponding to the image from the first waveguide section toward the plate, (2) the quarter-wave plate rotated the polarization of the light by a quarter wavelength, (3) one or more partially reflective surfaces partially transmitted and partially reflected the light, (4) one or more reflectors reflected the transmitted light back through the one or more partially reflective surfaces and the quarter-wave plate, (5) one or more partially reflective surfaces partially transmitted and partially reflected the reflected light, (6) the quarter-wave plate further rotated the polarization of the light by a quarter wavelength, and (7) the light was arranged to travel through the first waveguide section toward the second waveguide section. The waveguide system according to claim 1, comprising:

7. One or more partially reflective surfaces optically positioned between the first waveguide section and one or more reflectors, wherein (1) one or more first optical elements coupled output the light corresponding to the image from the first waveguide section through the second and third principal surfaces toward the one or more partially reflective surfaces and the one or more reflectors, (2) one or more partially reflective surfaces partially transmit and partially reflect the light, (3) one or more reflectors reflect the transmitted light back through the one or more partially reflective surfaces, (4) one or more partially reflective surfaces partially transmit and partially reflect the reflected light, and (5) one or more partially reflective surfaces through which the transmitted light travels toward the second waveguide section The waveguide system according to claim 1, comprising:

8. A first waveguide section having an aperture into which a light beam corresponding to an image from an image projector enters the waveguide system, comprising: first and second principal surfaces between which the light beam is guided by total internal reflection; and a first set of at least partially reflective surfaces configured to coupled output the light corresponding to the image from the first waveguide section so as to extend the aperture to a first dimension; A second waveguide section comprising: first and second principal surfaces configured to receive light from the first waveguide section, between which the light is guided by total internal reflection; and a second set of at least partially reflective surfaces configured to combine and output light corresponding to the image so as to extend the aperture to a second dimension nonparallel to the first dimension; Equipped with, The first waveguide section is configured such that one or more light beams corresponding to the first edge field of view of the image enter the waveguide system through the aperture at the first edge of the aperture; one or more light beams corresponding to the second edge field of view of the image enter the waveguide system through the aperture at the first edge of the aperture; and one or more light beams corresponding to the central field of view of the image enter the waveguide system through the aperture at the second edge of the aperture opposite the first edge. Waveguide system for near-eye displays.

9. The first waveguide section is configured such that one or more light beams corresponding to the first edge field of view of the image are at least partially reflected by the first at least partially reflective surface at the very edge of the first set of at least partially reflective surfaces; one or more light beams corresponding to the second edge field of view of the image are at least partially reflected by the second at least partially reflective surface at the very edge of the first set of at least partially reflective surfaces; and one or more light beams corresponding to the central field of view of the image are at least partially reflected by the third at least partially reflective surface at the very edge of the first set of at least partially reflective surfaces, which is positioned between the first at least partially reflective surface at the very edge and the second at least partially reflective surface at the very edge. Waveguide system according to claim 8.

10. A preliminary waveguide having internal facets configured to receive the image from the projector and perform preliminary aperture expansion to match the width of the aperture, The waveguide system according to claim 8, comprising:

11. The aforementioned image projector, A projector aperture corresponding to the opening of the first waveguide section, A matrix configured to generate the projected image, A collimating lens configured to receive and collimate light corresponding to the image generated by the matrix, A phase element is positioned relative to the matrix and the collimating lens to control the light beam distribution in the projector aperture, The waveguide system according to claim 8, including the following:

12. The aforementioned image projector, A projector aperture corresponding to the opening of the first waveguide section, A matrix configured to generate the projected image, A phase element is positioned in the projector to control the light beam distribution in the projector aperture such that one or more light beams corresponding to the central field of view of the image generated by the matrix are emitted from the projector aperture other than the center of the projector aperture. The waveguide system according to claim 8, including the following:

13. The aforementioned image projector, A projector aperture corresponding to the opening of the first waveguide section, A matrix configured to generate the projected image, A phase element is positioned in the projector to control the light beam distribution in the projector aperture such that one or more light beams corresponding to the edge field of view of the image generated by the matrix are emitted from the projector aperture at the center of the projector aperture. The waveguide system according to claim 8, including the following:

14. The aforementioned image projector, A projector aperture corresponding to the opening of the first waveguide section, A matrix configured to generate the projected image, A phase element disposed within the projector to control the light beam distribution in the projector aperture, A transparent wafer bordered with a relief pattern through which one or more light beams pass, or A diffractive optical element through which one or more light beams pass, A phase element which is one or both of the following, The waveguide system according to claim 8, including the following:

15. The aforementioned image projector, A projector aperture corresponding to the opening of the first waveguide section, A matrix configured to generate the projected image, A collimating lens is optically positioned between the projector aperture and the matrix, and configured to receive and collimate light corresponding to the image generated by the matrix. A phase element optically positioned between the matrix and the collimating lens to control the light beam distribution in the projector aperture, The waveguide system according to claim 8, including the following:

16. The aforementioned image projector, A projector aperture corresponding to the opening of the first waveguide section, Light source and A matrix optically positioned between the projector aperture and the light source, configured to receive light from the light source and generate the projected image, A collimating lens is optically positioned between the projector aperture and the matrix, and configured to receive and collimate light corresponding to the image generated by the matrix. A phase element optically positioned between the light source and the matrix, which controls the light beam distribution in the projector aperture, An optical component is optically positioned between the light source and the phase element, and is configured to optimize the optical power coupling in the projector aperture while minimizing the optical power required by the phase element. The waveguide system according to claim 8, including the following:

17. The aforementioned image projector, A projector aperture corresponding to the opening of the first waveguide section, Light source and A matrix optically positioned between the projector aperture and the light source, configured to receive light from the light source and generate the projected image, A phase element optically positioned between the light source and the matrix, which controls the light beam distribution in the projector aperture, A polarizing beam splitter (PBS) is optically positioned between the light source and the projector aperture, configured to reflect first-polarized light from the light source to the matrix via the phase element, reflect second-polarized light from the matrix to a polarizing reflector via the phase element, and reflect first-polarized light from the polarizing reflector to the projector aperture. An optical component is optically positioned between the light source and the phase element, and is configured to optimize the optical power coupling in the projector aperture while minimizing the optical power required by the phase element. The waveguide system according to claim 8, including the following:

18. The aforementioned image projector, A projector aperture corresponding to the opening of the first waveguide section, Light source and A matrix optically positioned between the projector aperture and the light source, configured to receive light from the light source and generate the projected image, A collimating lens is optically positioned between the projector aperture and the matrix, and configured to receive and collimate light corresponding to the image generated by the matrix. A phase element optically positioned between the light source and the matrix, which controls the light beam distribution in the projector aperture, An optical component is optically positioned between the light source and the phase element, and between the phase element and the matrix, and is configured to optimize the optical power coupling in the projector aperture while minimizing the optical power required by the phase element. The waveguide system according to claim 8, including the following:

19. The aforementioned image projector, A projector aperture corresponding to the opening of the first waveguide section, Light source and A matrix optically positioned between the projector aperture and the light source, configured to receive light from the light source and generate the projected image, A phase element optically positioned between the light source and the matrix, which controls the light beam distribution in the projector aperture, A polarizing beam splitter (PBS) is optically positioned between the light source and the projector aperture, configured to reflect first-polarized light from the light source to the matrix via the phase element, reflect second-polarized light from the matrix to a polarizing reflector, and reflect the first-polarized light from the polarizing reflector to the projector aperture. An optical component is optically positioned between the light source and the phase element, and between the phase element and the matrix, and is configured to optimize the optical power coupling in the projector aperture while minimizing the optical power required by the phase element. The waveguide system according to claim 8, including the following:

20. The aforementioned image projector, A projector aperture corresponding to the opening of the first waveguide section, Light source and A matrix optically positioned between the projector aperture and the light source, configured to receive light from the light source and generate the projected image, Includes, Each reflective pixel element on the matrix is ​​set to its respective inclination in order to control the light beam distribution in the projector aperture. Waveguide system according to claim 8.

21. The aforementioned image projector, A projector aperture corresponding to the opening of the first waveguide section, Light source and A matrix optically positioned between the projector aperture and the light source, configured to receive light from the light source and generate the projected image, Includes, Each reflective pixel element on the matrix is ​​set to its respective inclination such that one or more light beams corresponding to the central field of view of the image are emitted from the projector aperture at the edge of the projector aperture. Waveguide system according to claim 8.

22. The aforementioned image projector, A projector aperture corresponding to the opening of the first waveguide section, Light source and A matrix optically positioned between the projector aperture and the light source, configured to receive light from the light source and generate the projected image, Includes, Each reflective pixel element on the matrix is ​​set to its respective inclination such that one or more light beams corresponding to the edge field of view of the image are emitted from the projector aperture at the center of the projector aperture. Waveguide system according to claim 8.

23. The aforementioned image projector, A projector aperture corresponding to the opening of the first waveguide section, Light source and A matrix optically positioned between the projector aperture and the light source, configured to receive light from the light source and generate the projected image, A polarizing beam splitter (PBS) is optically positioned between the light source and the projector aperture, configured to reflect first-polarized light from the light source to the matrix, reflect second-polarized light from the matrix to a polarizing reflector, and reflect first-polarized light from the polarizing reflector to the projector aperture. Includes, Each reflective pixel element on the matrix is ​​set to its respective inclination such that one or more light beams corresponding to the edge field of view of the image are emitted from the projector aperture at the center of the projector aperture. Waveguide system according to claim 8.

24. The aforementioned image projector, Two or more adjacent projectors, wherein the first projector has a first projector aperture corresponding to a first portion of the opening of the first waveguide section, and the second projector has a second projector aperture corresponding to a second portion of the opening of the first waveguide section that is different from the first portion of the opening of the first waveguide section, and the first projector is configured to project a first portion of the image, and the second projector is configured to project a second portion of the image that is different from the first portion of the image. The waveguide system according to claim 8, including the following:

25. Projector aperture and A matrix configured to generate a projected image, A collimating lens configured to receive and collimate light corresponding to the image generated by the matrix, A phase element is positioned in the projector to control the light beam distribution in the projector aperture such that one or more light beams corresponding to the central field of view of the image generated by the matrix are emitted from the projector aperture at the edge of the projector aperture. An image projector equipped with the following features.

26. The image projector according to claim 25, wherein the phase element is positioned in the projector to control the distribution of light beams in the projector aperture, such that one or more light beams corresponding to the edge field of view of the image generated by the matrix are emitted from the projector aperture at the center of the projector aperture.

27. The aforementioned phase button, A transparent wafer bordered with a relief pattern through which one or more light beams pass, or A diffractive optical element through which one or more light beams pass, The image projector according to claim 25, which is one or both of the above.

28. The collimating lens is optically positioned between the projector aperture and the matrix. The phase element is optically positioned between the matrix and the collimating lens to control the light beam distribution in the projector aperture. The image projector according to claim 25.

29. Equipped with optical components, The matrix is ​​optically arranged between the projector aperture and the light source. The collimating lens is optically positioned between the projector aperture and the matrix. The phase element is optically positioned between the light source and the matrix to control the light beam distribution in the projector aperture. The optical component is optically positioned between the light source and the phase element and is configured to optimize the optical power coupling in the projector aperture while minimizing the optical power required by the phase element. The image projector according to claim 25.

30. A polarizing beam splitter (PBS) configured to reflect first polarized light from the light source to the matrix via the phase element, reflect second polarized light from the matrix to a polarizing reflector via the phase element, and reflect the first polarized light from the polarizing reflector to the projector aperture, Optical components, Equipped with, The matrix is ​​optically arranged between the projector aperture and the light source. The phase element is optically positioned between the light source and the matrix to control the light beam distribution in the projector aperture. The polarizing beam splitter (PBS) is optically arranged between the light source and the projector aperture. The optical component is optically positioned between the light source and the phase element and is configured to optimize the optical power coupling in the projector aperture while minimizing the optical power required by the phase element. The image projector according to claim 25.

31. Equipped with optical components, The matrix is ​​optically arranged between the projector aperture and the light source. The collimating lens is optically positioned between the projector aperture and the matrix. The phase element is optically arranged between the light source and the matrix. The optical components are optically arranged between the light source and the phase element, and between the phase element and the matrix, and are configured to optimize the optical power coupling in the projector aperture while minimizing the optical power required by the phase element. The image projector according to claim 25.

32. A polarizing beam splitter (PBS) configured to reflect first-polarized light from the light source to the matrix via the phase element, reflect second-polarized light from the matrix to a polarizing reflector, and reflect the first-polarized light from the polarizing reflector to the projector aperture, Optical components, Equipped with, The matrix is ​​optically arranged between the projector aperture and the light source. The phase element is optically arranged between the light source and the matrix. The polarizing beam splitter (PBS) is optically arranged between the light source and the projector aperture. The optical components are optically arranged between the light source and the phase element, and between the phase element and the matrix, and are configured to optimize the optical power coupling in the projector aperture while minimizing the optical power required by the phase element. The image projector according to claim 25.

33. A first waveguide section having first and second main surfaces and an aperture into which a light beam corresponding to an image from an image projector enters the waveguide system, wherein the first waveguide section is configured to propagate the light in the first and second dimensions while guiding the light in a third dimension nonparallel to the first and second dimensions by total internal reflection between the first and second main surfaces, A redirection component configured to receive the light beam from the first waveguide section and redirect the light beam to a third dimension that is non-parallel to the first and second dimensions, A second waveguide section having first and second main surfaces, receiving the light beam redirected by the redirecting component, and configured to guide the light beam to the second dimension by total internal reflection between the first and second main surfaces so that the light propagates to the third and first dimensions; One or more first optical elements disposed between the first waveguide section, the second waveguide section, or the first waveguide section and the second waveguide section, and configured to extend the aperture to the first dimension, One or more second optical elements arranged in the second waveguide section and configured to combine and output the second-dimensional image so as to extend the aperture to the third dimension, A waveguide system for near-eye displays, equipped with the features mentioned above.

34. The waveguide system according to claim 33, wherein the direction-changing component is one or both of a reflector and a prism.

35. The waveguide system according to claim 33, wherein the direction-changing component corresponds to one or more first optical elements.

36. The waveguide system according to claim 33, further comprising a waveplate disposed between the first waveguide section and the second waveguide section.

37. Waveguide system according to claim 33, wherein the movement of light from the aperture to the coupled output by the second set of partially reflective surfaces corresponds to an optical path, and comprises a longitudinal partial reflector positioned before or after the second waveguide section in the optical path.

38. The waveguide system according to claim 33, wherein the first waveguide section and the second waveguide section are arranged orthogonally to each other when viewed from a side view of the waveguide system.

39. Waveguide system according to claim 33, wherein the thickness between the first main surface and the second main surface of the first waveguide section is greater than the thickness between the first main surface and the second main surface of the second waveguide section.

40. The waveguide system according to claim 33, wherein the one or more second optical elements correspond to a second set of parallel, partially reflective surfaces arranged at an oblique angle to the first and second principal surfaces of the second waveguide section.

41. Waveguide system according to claim 33, wherein one or more first optical elements correspond to a first set of parallel partially reflective surfaces or a first diffraction grating, and one or more second optical elements correspond to a second set of parallel partially reflective surfaces or a second diffraction grating.

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