Reflective polarizer hologram layer in augmented reality / virtual reality optical components

Abstract

The invention relates to a reflective polarizer hologram layer in an augmented reality / virtual reality optical assembly. Combination of a reflective polarizer hologram (rPVH) layer and a quarter-wave plate (QWP) may be used to provide optical power and correct chromatic aberration in optical components of augmented reality and / or virtual reality (AR / VR) near-eye display devices. The rPVH layer introduces more degrees of freedom to further improve the contrast of the optical system and reduce the thickness / weight of the optical assembly. The rPVH layer is flexible, thus allowing for bending lamination on the optical lens. In addition, the rPVH layer is sensitive to circular polarization. Thus, the rPVH layer can filter right-handed circular polarization (RHCP) or left-handed circular polarization (LHCP) without the need for QWP.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims the priority of U.S. Non - Provisional Patent Application No. 18 / 392,749, filed on December 21, 2023, the entire content of which is incorporated herein by reference. Technical Field

[0003] This patent application generally relates to Augmented Reality and / or Virtual Reality (AR / VR) display devices. In particular, it relates to providing higher optical power and higher - order aberration correction through a reflective Polarization Volume Hologram (rPVH) layer in an optical component. Background Art

[0004] In recent years, with the latest technological advancements, the prevalence and dissemination of content creation and delivery have increased significantly. In particular, interactive content such as virtual reality (VR) content, augmented reality (AR) content, mixed reality (MR) content, and content within and associated with real and / or virtual environments (e.g., "metaverse") has become attractive to consumers.

[0005] To facilitate the delivery of these and other related contents, service providers have strived to provide various forms of wearable display systems. One such example can be a Head - Mounted Display (HMD) device, such as a wearable eyewear, a wearable headset, or glasses. In some examples, the Head - Mounted Display (HMD) device can project or direct light to display virtual objects in, for example, virtual reality (VR) applications, augmented reality (AR) applications, or mixed reality (MR) applications, or to combine an image of a real object with virtual objects. For example, in an AR system, a user can view both an image of a virtual object (e.g., a Computer - Generated Image (CGI)) and an image of the surrounding environment. The Head - Mounted Display (HMD) device can also present interactive content, where the gaze of the user (wearer) can be used as an input to the interactive content. Summary of the Invention

[0006] According to one aspect of the present disclosure, there is provided an optical component for an augmented reality / virtual reality (AR / VR) display system, the optical component comprising: a reflective polarization volume hologram (rPVH) layer; a quarter-wave plate (QWP) layer; and one or more optical elements, wherein the rPVH layer and the QWP layer are flexible, and the rPVH layer and the QWP layer are applied to one of the one or more optical elements to provide optical power and correct aberrations in the optical component.

[0007] According to another aspect of the present disclosure, there is provided an augmented reality / virtual reality (AR / VR) near-eye display device, the AR / VR near-eye display device comprising a light source, an optical component, and a display, the optical component comprising: a reflective polarization volume hologram (rPVH) layer; a quarter-wave plate (QWP) layer; and one or more optical elements, wherein the rPVH layer and the QWP layer are flexible, and the rPVH layer and the QWP layer are applied to one of the one or more optical elements to provide optical power and correct aberrations in the optical component; the display projects light into an eye box.

[0008] According to yet another aspect of the present disclosure, there is provided a method for assembling an augmented reality / virtual reality (AR / VR) near-eye display device, the method comprising: applying a reflective polarization volume hologram (rPVH) layer to a quarter-wave plate (QWP) layer; adjusting the curvatures of the rPVH layer and the QWP layer to match the curvature of an optical element of an optical component of the AR / VR near-eye display device; assembling the optical component together with the rPVH layer, the QWP layer, and one or more optical elements; and assembling the AR / VR near-eye display device to combine the optical component with a light source and one or more additional components. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The features of the present disclosure are illustrated by way of example and are not limited to the following drawings, in which like reference numerals refer to like elements. Those skilled in the art will readily recognize from the following that alternative examples of the structures and methods shown in the drawings may be employed without departing from the principles described herein.

[0010] Figure 1 A block diagram showing an artificial reality system environment including a near-eye display according to an example is shown.

[0011] Figures 2A to 2C Various views of a near-eye display device in the form of a head-mounted display (HMD) device according to an example are shown.

[0012] Figure 3Shows a perspective view of a near-eye display in the form of a pair of glasses according to an example.

[0013] Figure 4A And Figure 4B Shows light projection in an AR / VR near-eye display device by an optical component according to an example.

[0014] Figure 5 Shows the modulation transfer function (MTF) of an optical component with an rPVH layer and the modulation transfer function of an optical component without an rPVH layer according to an example.

[0015] Figure 6 Shows an rPVH layer structure with in-plane periodicity and vertical periodicity according to an example.

[0016] Figure 7 Shows a flowchart of a method for forming a near-eye display device having an rPVH-QWP layer in its optical component according to an example. Detailed Description

[0017] For purposes of simplicity and illustration, the present application is described primarily with reference to examples of the present application. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent that the present application may be practiced without limitation to these specific details. In other instances, some methods and structures that are readily understood by those of ordinary skill in the art are not described in detail so as not to unnecessarily obscure the present application. As used herein, the terms "a" and "an" are intended to denote at least one of a particular element, the term "include" means including but not limited to, the term "including" means including but not limited to, and the term "based on" means at least partially based on.

[0018] Augmented and / or virtual reality (AR / VR) systems typically utilize an optical component (also referred to as a pancake system or an optical stack) with a reflective polarizer to achieve the capabilities of refractive optics. Reflective polarizers are typically used in conjunction with a quarter-wave plate (QWP) and are less flexible for being bent and laminated (e.g., on an optical lens). Additionally, for optical lenses with a reflective polarizer and optical lenses without a reflective polarizer (both of which have positive optical power), some systems use the same material, which may result in in-band chromatic aberration.

[0019] Some traditional systems use a cholesteric liquid crystal (CLC) layer to replace the combination of a reflective polarizer - quarter-wave plate, or use a Pancharatnam-Berry phase (PBP) lens for chromatic aberration correction. Both methods pose challenges in terms of increasing the thickness and / or weight of the optical components and the performance of the optical components.

[0020] In some examples of the present disclosure, a reflective polarizer hologram (rPVH) layer can be used to provide optical power and correct chromatic aberration in the optical components of an augmented reality and / or virtual reality (AR / VR) near-eye display device. The rPVH layer introduces more degrees of freedom to further improve the contrast of the optical system and reduce the thickness / weight of the optical components. In addition, the rPVH layer is flexible, thus allowing bending and lamination on an optical lens. In addition, the rPVH layer is sensitive to circular polarization. Therefore, the rPVH layer can filter right-handed circular polarization (RHCP) or left-handed circular polarization (LHCP) without the need for a QWP.

[0021] While some advantages and benefits of the present disclosure are obvious, other advantages and benefits can include increased optical power, shrinkage, reduction in the thickness and / or weight of the optical components in an AR / VR near-eye display device, and reduction of the risk of bending and lamination (e.g., on an optical lens).

[0022] Figure 1 A block diagram of an artificial reality system environment 100 including a near-eye display according to an example is shown. As used herein, a "near-eye display" can refer to a device (e.g., an optical device) that can be very close to a user's eyes. As used herein, "artificial reality" can refer to aspects such as "virtual reality", or an environment of real elements and virtual elements, and can include the use of technologies associated with virtual reality (VR), augmented reality (AR), and / or mixed reality (MR). As used herein, a "user" can refer to a user or wearer of a "near-eye display".

[0023] As Figure 1As shown, the artificial reality system environment 100 may include a near-eye display 120, an optional external imaging device 150, and an optional input / output interface 140, each of which may be coupled to a console 110. In some cases, the console 110 may be optional as the functions of the console 110 may be integrated into the near-eye display 120. In some examples, the near-eye display 120 may be a head-mounted display (HMD) that presents content to a user.

[0024] In some cases, for a near-eye display system, it may generally be desirable to expand the comfortable viewing area, reduce display haze, improve image quality (e.g., resolution and contrast), reduce physical size, increase power efficiency, and increase or expand the field of view (FOV). As used herein, "field of view (FOV)" may refer to the angular extent of an image as seen by a user, which is typically measured in degrees as viewed by a single eye (for a monocular head-mounted display (HMD)) or both eyes (for a binocular head-mounted display (HMD)). Additionally, as used herein, "comfortable viewing area" may be a two-dimensional box that can be located in front of a user's eyes from which the displayed image from an image source can be viewed.

[0025] In some examples, in a near-eye display system, light from the surrounding environment may pass through the "see-through" region (e.g., a transparent substrate) of a waveguide display to reach the user's eyes. For example, in a near-eye display system, light of a projected image may be coupled into the transparent substrate of a waveguide, propagate within the waveguide, and be coupled out or extracted from the waveguide at one or more locations to replicate an exit pupil and expand the comfortable viewing area.

[0026] In some examples, the near-eye display 120 may include one or more rigid bodies that may be rigidly or non-rigidly coupled to each other. In some examples, a rigid coupling between the rigid bodies may cause the coupled rigid bodies to act as a single rigid entity, while in other examples, a non-rigid coupling between the rigid bodies may allow the rigid bodies to move relative to each other.

[0027] In some examples, the near-eye display 120 may be implemented in any suitable form factor, including a head-mounted display (HMD), a pair of glasses, or other similar wearable eyewear or wearable device. Reference will be made hereinafter to Figure 2A and Figure 3A further example of the near-eye display 120 is described. Additionally, in some examples, the functionality described herein can be used in a head-mounted display (HMD) or head-mounted viewer that combines an image of the environment external to the near-eye display 120 and artificial reality content (e.g., computer-generated images). Thus, in some examples, the near-eye display 120 can enhance an image of the physical real-world environment external to the near-eye display 120 with generated and / or superimposed digital content (e.g., images, videos, sounds, etc.) to present augmented reality to the user.

[0028] In some examples, the near-eye display 120 can include any number of display electronics 122, display optics 124, and an eye-tracking unit 130. In some examples, the near-eye display 120 can also include one or more locators 126, one or more position sensors 128, and an Inertial Measurement Unit (IMU) 132. In some examples, the near-eye display 120 can omit any one of the eye-tracking unit 130, one or more locators 126, one or more position sensors 128, and the IMU 132, or can include additional elements.

[0029] In some examples, the display electronics 122 can display an image to the user or assist in displaying an image to the user based on data received from, for example, an optional console 110. In some examples, the display electronics 122 can include one or more display panels. In some examples, the display electronics 122 can include any number of pixels that emit light of a dominant color such as red, green, blue, white, or yellow. In some examples, the display electronics 122 can display a three-dimensional (3D) image, for example, using a stereoscopic effect generated by a two-dimensional panel to create a subjective perception of image depth.

[0030] In some examples, the near-eye display 120 can include a projector (not shown) that can form an image in an angular field for direct viewing by the viewer's eye through the pupil. The projector can employ a controllable light source (e.g., a laser source) and a Micro-Electromechanical System (MEMS) beam scanner to generate a light field from, for example, a collimated beam. In some examples, the same projector or a different projector can be used to project a fringe pattern onto the eye, which can be captured and analyzed by a camera (e.g., by the eye-tracking unit 130) to determine the position, gaze, etc. of the eye (pupil).

[0031] In some examples, the display optical device 124 may optically display image content (e.g., using optical waveguides and / or couplers), or magnify received image light from the display electronics 122, correct optical errors associated with the image light, and / or present the corrected image light to a user of the near-eye display 120. In some examples, the display optical device 124 may include a single optical element or any number of combinations of various optical elements, as well as mechanical couplers for maintaining the relative spacing and orientation of the optical elements in the combination. In some examples, one or more of the optical elements in the display optical device 124 may have optical coatings, such as anti-reflection coatings, reflective coatings, filter coatings, and / or combinations of different optical coatings.

[0032] In some examples, the display optical device 124 may also be designed to correct one or more types of optical errors, such as two-dimensional optical errors, three-dimensional optical errors, or any combination thereof. Examples of two-dimensional errors may include barrel distortion, pincushion distortion, longitudinal chromatic aberration, and / or lateral chromatic aberration. Examples of three-dimensional errors may include spherical aberration, chromatic aberration, field curvature, and astigmatism.

[0033] In some examples, one or more locators 126 may be objects located at specific positions relative to each other and relative to a reference point on the near-eye display 120. In some examples, the optional console 110 may identify one or more locators 126 in an image captured by the optional external imaging device 150 to determine the position, orientation, or both the position and orientation of the artificial reality head-mounted viewer. Each of the one or more locators 126 may be a light-emitting diode (LED), a corner cube reflector, a reflective marker, a class of light sources that contrast with the environment in which the near-eye display 120 operates, or any combination thereof.

[0034] In some examples, the external imaging device 150 may include one or more cameras, one or more video cameras, any other device capable of capturing an image including one or more locators 126, or any combination thereof. The optional external imaging device 150 may be configured to detect light emitted or reflected from one or more locators 126 in the field of view of the optional external imaging device 150.

[0035] In some examples, one or more position sensors 128 may generate one or more measurement signals in response to movement of the near-eye display 120. Examples of the one or more position sensors 128 may include any number of accelerometers, gyroscopes, magnetometers, and / or other motion detection sensors or error correction sensors, or any combination thereof.

[0036] In some examples, the inertial measurement unit (IMU) 132 can be an electronic device that generates fast calibration data based on received measurement signals from one or more position sensors 128. One or more position sensors 128 can be located external to the inertial measurement unit (IMU) 132, inside the inertial measurement unit (IMU) 132, or any combination thereof. Based on one or more measurement signals from one or more position sensors 128, the inertial measurement unit (IMU) 132 can generate fast calibration data that represents an estimated position of the near-eye display 120 relative to an initial position of the near-eye display 120. For example, the inertial measurement unit (IMU) 132 can integrate the received measurement signals from an accelerometer over time to estimate a velocity vector, and integrate the velocity vector over time to determine an estimated position of a reference point on the near-eye display 120. Alternatively, the inertial measurement unit (IMU) 132 can provide sampled measurement signals to an optional console 110, which can determine the fast calibration data.

[0037] The eye tracking unit 130 can include one or more eye tracking systems. As used herein, "eye tracking" can refer to determining the position or relative position of an eye, including the orientation, position, and / or gaze of a user's eye. In some examples, an eye tracking system can include an imaging system that acquires one or more images of the eye, and can optionally include a light emitter that can generate light (e.g., a stripe pattern) that is directed toward the eye such that the light reflected by the eye can be acquired by the imaging system (e.g., a camera). In other examples, the eye tracking unit 130 can acquire reflected radio waves emitted by a micro radar unit. This eye-related data can be used to determine or predict the position, orientation, movement, location, and / or gaze of the eye.

[0038] In some examples, the near-eye display 120 can use the orientation of the eye to introduce depth cues (e.g., blurring an image outside of the user's primary line of sight), gather heuristic information about user interactions in virtual reality (VR) media (e.g., the time spent on any particular object, item, or frame as a function of the experienced stimuli), some other function based at least in part on the orientation of at least one of the user's eyes, or any combination thereof. In some examples, since the orientation can be determined for both of the user's eyes, the eye tracking unit 130 can be able to determine where the user is looking or predict any user patterns, etc.

[0039] In some examples, the input / output interface 140 can be a device that allows a user to send action requests to the optional console 110. As used herein, an "action request" can be a request to perform a specific action. For example, an action request can be to start an application or end an application, or to perform a specific action within an application. The input / output interface 140 can include one or more input devices. Example input devices can include a keyboard, a mouse, a game controller, gloves, buttons, a touch screen, or any other suitable device for receiving an action request and transmitting the received action request to the optional console 110. In some examples, the action request received by the input / output interface 140 can be transmitted to the optional console 110, which can perform an action corresponding to the requested action.

[0040] In some examples, the console 110 can provide content to the near-eye display 120 for presentation to a user based on information received from one or more of an external imaging device 150, the near-eye display 120, and the input / output interface 140. For example, in Figure 1 the example shown, the optional console 110 can include an application repository 112, a head-mounted viewer tracking module 114, a virtual reality engine 116, and an eye tracking module 118. Some examples of the optional console 110 can include modules different from or additional to the modules described in connection with Figure 1 The functions described further below can be distributed among the components of the optional console 110 in a manner different from the manner described herein.

[0041] In some examples, the optional console 110 can include a processor and a non-transitory computer-readable storage medium that stores instructions executable by the processor. The processor can include multiple processing units that execute instructions in parallel. The non-transitory computer-readable storage medium can be any memory, such as a hard disk drive, a removable memory, or a solid-state drive (e.g., flash memory or dynamic random access memory (DRAM)). In some examples, the modules of the optional console 110 described in connection with Figure 1 can be encoded as instructions in the non-transitory computer-readable storage medium, which, when executed by the processor, cause the processor to perform the functions described further below. It should be understood that the optional console 110 may or may not be required, or the optional console 110 can be integrated with or separate from the near-eye display 120.

[0042] In some examples, the application repository 112 may store one or more applications for execution by the optional console 110. An application may include a set of instructions that, when executed by a processor, generate content for presentation to a user. Examples of applications may include gaming applications, conferencing applications, video playback applications, or other suitable applications.

[0043] In some examples, the head-mounted viewer tracking module 114 may use slow calibration information from the external imaging device 150 to track the movement of the near-eye display 120. For example, the head-mounted viewer tracking module 114 may use locators observed from the slow calibration information and a model of the near-eye display 120 to determine the position of a reference point of the near-eye display 120. Additionally, in some examples, the head-mounted viewer tracking module 114 may use multiple portions of the following: fast calibration information, slow calibration information, or any combination thereof, to predict a future position of the near-eye display 120. In some examples, the head-mounted viewer tracking module 114 may provide the estimated or predicted future position of the near-eye display 120 to the virtual reality engine 116.

[0044] In some examples, the virtual reality engine 116 may execute an application within the artificial reality system environment 100 and receive position information of the near-eye display 120, acceleration information of the near-eye display 120, velocity information of the near-eye display 120, a predicted future position of the near-eye display 120, or any combination thereof, from the head-mounted viewer tracking module 114. In some examples, the virtual reality engine 116 may also receive information on the estimated eye position and orientation from the eye tracking module 118. Based on the received information, the virtual reality engine 116 may determine the content to be provided to the near-eye display 120 for presentation to the user.

[0045] In some examples, the position of the projector of the display system may be adjusted to enable any number of design modifications. For example, in some cases, the projector may be located in front of the viewer's eyes (i.e., "front-mounted" placement). In some examples, in a front-mounted placement, the projector of the display system may be located at a position away from the user's eyes (i.e., "world-side"). In some examples, a head-mounted display (HMD) device may utilize a front-mounted placement to direct light towards one or both eyes of the user to project an image.

[0046] As mentioned herein, the combination of a reflective polarizing volume hologram (rPVH) layer and a quarter-wave plate (QWP) can be used to provide optical power and correct chromatic aberration in the optical components of an augmented reality and / or virtual reality (AR / VR) near-eye display device. The rPVH layer can introduce additional degrees of freedom to further improve the contrast of the optical system and reduce the thickness / weight of the optical components.

[0047] Figures 2A to 2C Various views of a near-eye display device in the form of a head-mounted display (HMD) device according to an example are shown. In some examples, the head-mounted display (HMD) device 200 can be part of a virtual reality (VR) system, an augmented reality (AR) system, a mixed reality (MR) system, other systems using displays or wearable devices, or any combination thereof. As Figure 2A shown in schematic view 200A, the head-mounted display (HMD) device 200 can include a body 220 and a headband 230. A front perspective view of the head-mounted display (HMD) device 200 also shows the bottom side 223, the front side 225, and the right side 229 of the body 220. In some examples, the headband 230 can have an adjustable or extendable length. In particular, in some examples, there can be sufficient space between the body 220 of the head-mounted display (HMD) device 200 and the headband 230 to allow a user to wear the head-mounted display (HMD) device 200 on the user's head. For example, the length of the headband 230 can be adjustable to accommodate a range of user head sizes. In some examples, the head-mounted display (HMD) device 200 can include additional, fewer, and / or different components, such as a display 210 for presenting augmented reality (AR) / virtual reality (VR) content to the wearer and a camera for capturing images or videos of the wearer's environment.

[0048] As Figure 2B shown in the bottom perspective view of schematic view 200B, the display 210 can include one or more display components and present media or other digital content to a user (wearer), the media or other digital content including a virtual view and / or an augmented view of the physical real-world environment with computer-generated elements. Examples of the media or digital content presented by the head-mounted display (HMD) device 200 can include images (e.g., two-dimensional images (2D) or three-dimensional images (3D)), videos (e.g., 2D videos or 3D videos), audio, or any combination thereof. In some examples, the user can interact with the presented images or videos through an eye-tracking sensor encapsulated in the body 220 of the head-mounted display (HMD) device 200. The eye-tracking sensor can also be used to adjust and improve the quality of the presented content.

[0049] In some examples, a head-mounted display (HMD) device 200 can include various sensors (not shown), such as depth sensors, motion sensors, position sensors, and / or eye-tracking sensors. Some of these sensors can use any number of structured light patterns or unstructured light patterns for sensing purposes. In some examples, the head-mounted display (HMD) device 200 can include an input / output interface for communicating with a console communicatively coupled to the head-mounted display (HMD) device 200 by wire or wirelessly. In some examples, the head-mounted display (HMD) device 200 can include a virtual reality engine (not shown) that can execute applications within the head-mounted display (HMD) device 200 and receive depth information, position information, acceleration information, velocity information, predicted future positions, or any combination thereof of the head-mounted display (HMD) device 200 from various sensors.

[0050] In some examples, the information received by the virtual reality engine can be used to generate signals (e.g., display instructions) to the display 210. In some examples, the head-mounted display (HMD) device 200 can include locators (not shown) that can be located at fixed positions on the body 220 of the head-mounted display (HMD) device 200 relative to each other and relative to a reference point. Each of these locators can emit light that can be detected by an external imaging device. This can be useful for head-tracking purposes or other movement / orientation purposes. It should be understood that other elements or components can be used in addition to or in place of such locators.

[0051] It should be understood that in some examples, projectors mounted in a display system can be placed near and / or close to a user's eyes (i.e., "eye-side"). In some examples, as discussed herein, projectors for a display system shaped like glasses can be mounted or positioned in the temple arms of the glasses (i.e., the top far corner on the lens side). It should be understood that in some cases, using a back-mounted projector placement can help reduce the size or volume of any required housing for the display system, which can also significantly improve the user experience.

[0052] In some examples, the display subsystem of a near-eye display device can include an optical component having a reflective polarization hologram (rPVH) layer and / or a quarter-wave plate (QWP) to provide optical power and correct chromatic aberration.

[0053] Figure 3Shows a perspective view of a near-eye display 300 in the form of a pair of glasses (or other similar eye-wearable device) according to an example. In some examples, the near-eye display 300 can be a Figure 1 specific example of the near-eye display 120 and can be configured to operate as a virtual reality display, an augmented reality (AR) display, and / or a mixed reality (MR) display.

[0054] In some examples, the near-eye display 300 can include a frame 305 and a display 310. In some examples, the display 310 can be configured to present media or other content to a user. In some examples, the display 310 can include display electronics and / or display optics similar to the components described with respect to Figure 1 and Figures 2A to 2C described. For example, as described above with respect to Figure 1 the near-eye display 120, the display 310 can include a liquid crystal display (LCD) display panel, a light emitting diode (LED) display panel, or an optical display panel (e.g., a waveguide display assembly). In some examples, the display 310 can also include any number of optical components, such as waveguides, gratings, lenses, mirrors, etc. In other examples, the display 310 can include a projector, or instead of the display 310, the near-eye display 300 can include a projector.

[0055] In some examples, the near-eye display 300 can also include various sensors located on or within the frame 305. In some examples, as shown, the various sensors can include any number of depth sensors, motion sensors, position sensors, inertial sensors, and / or ambient light sensors. In some examples, the various sensors can include any number of image sensors configured to generate image data representing different fields of view in one or more different directions. In some examples, the various sensors can be used as input devices to control or affect the content displayed by the near-eye display and / or to provide an interactive virtual reality (VR), augmented reality (AR), and / or mixed reality (MR) experience to a user of the near-eye display 300. In some examples, the various sensors can also be used for stereoscopic imaging or other similar applications.

[0056] Figure 4A and Figure 4BShows light projection in an AR / VR near-eye display device through an optical component according to an example. Schematic diagram 400A shows the light projection part of the eye tracking system 402, which may include a light source 404, an optical component (optical stack) 406, and the light reaching the projection plane 410 transmitted by the light source 404 and processed by the optical component 406. The optical component 406 may include elements for focusing or defocusing incident light, filtering light, correcting aberrations, or dealing with other optical problems, so as to provide high-quality projection to the projection plane 410.

[0057] Schematic diagram 400B shows an example detailed configuration of the optical component 406 having an rPVH layer 424, a QWP 426, and an optical lens 428, which provides the light from the light source 422 onto the projection plane 410. The optical component 406 having an rPVH layer 424, a QWP 426, and an optical lens 428 provides optical power and corrects chromatic aberration without introducing negative optical power. The rPVH layer 424 introduces more degrees of freedom to further improve the contrast of the optical system and reduce the thickness / weight of the optical component 406. Since the rPVH introduces more degrees of freedom for bending light (e.g., compared with RP+QWP), it corrects monochromatic aberration. In addition, the rPVH layer 424 and the QWP 426 are flexible, thus allowing bending lamination on the optical lens 428. In addition, the rPVH layer 424 is sensitive to circular polarization and can filter right-handed circular polarization (RHCP) or left-handed circular polarization (LHCP). The light source 422 can be any coherent light source and incoherent light source (such as VCSEL or LED), or multiple light sources (such as a VCSEL array, a micro-LED array, etc.). In some examples, the optical component may include other elements (such as filters, diffractive optical elements (DOE), and similar elements). In some examples, by moving the flat plate (required for the RP+QWP system), the system can introduce adjustment capabilities.

[0058] In an augmented reality (AR) / virtual reality (VR) system, a pancake system (optical component) targeting retinal-level resolution requires in-band chromatic aberration correction and a good modulation transfer function (MTF). The MTF of a lens or any optical system is a measure of its ability to transfer contrast from an object to an image at a specific resolution. Therefore, the MTF is a way to combine resolution and contrast into a single specification. Resolution is the ability of an imaging system to distinguish object details. Contrast (also called modulation) can be defined as the degree of truthfulness in transferring the minimum intensity value and the maximum intensity value from the object plane to the image plane.

[0059] Figure 5Shows the modulation transfer function (MTF) of an optical component with an rPVH layer and the modulation transfer function of an optical component without an rPVH layer according to an example.

[0060] Schematic diagram 500 shows the modulation transfer function (MTF) 502 of an optical component without rPVH. This diagram shows the MTF on the spatial frequency (cycles / mm) axis and the modulus axis of the optical transfer function (OTF) in the wavelength range from 510 nm to 550 nm. Schematic diagram 500 also shows the modulation transfer function (MTF) 504 of the same optical component with rPVH on the spatial frequency (cycles / mm) axis and the modulus axis of the optical transfer function (OTF) in the wavelength range from 510 nm to 550 nm. As shown by the comparison of the two curves, the MTF of the optical component configuration with rPVH is significantly improved.

[0061] Figure 6 Shows an rPVH layer structure with in-plane periodicity and vertical periodicity according to an example.

[0062] Schematic diagram 600 shows an example internal structure of the rPVH layer 602, where the liquid crystal (LC) is in a helical twisted alignment and the helical axis is perpendicular to the substrate. The in-plane periodicity is represented as Λx, and the vertical periodicity is represented as Λy, where the helical pitch P = 2Λy. The rPVH layer is essentially similar to an inclined multilayer structure of circularly polarized light with the same handedness as the helical twist. Due to the inherent high refractive index contrast (>0.15), the rPVH layer provides high efficiency and a large reflection bandwidth. The thickness of the rPVH layer is directly related to the efficiency.

[0063] Figure 7 Shows a flowchart of a method for manufacturing a near-eye display device having an rPVH-QWP layer in its optical component according to an example. Method 700 is provided by way of example, but there can be various ways to perform the methods described herein. Method 700 can be executed by one or more processing components of a system or a combination of systems or otherwise executed to implement other models. Figure 7 Each box shown in can further represent one or more processes, methods, or subroutines, and one or more of these boxes can include machine-readable instructions that are stored on a non-transitory computer-readable medium and executed by a processor or other type of processing circuit to perform one or more operations described herein.

[0064] At block 702, the rPVH layer can be applied to the QWP layer, although in some examples, the rPVH layer can be used without a QWP layer. Since both layers are flexible, the combination (or just the rPVH layer) can be directly applied to a curved surface.

[0065] At block 704, the curvature of the rPVH-QWP layer can be adjusted to match the curvature of the substrate (such as an optical lens) to which they will be applied. At block 706, the optical component can be combined with additional elements (such as one or more optical lenses, filters, diffractive optical elements (DOEs), etc.). Subsequently, at block 708, a near-eye display device for an AR / VR display can be assembled using the optical component and other components (such as a frame and one or more displays, one or more light sources, one or more power modules, one or more processors, one or more transceivers, etc.).

[0066] According to an example, a method of manufacturing an AR / VR display device having an optical component including an rPVH and a QWP layer is described herein. A system for manufacturing an AR / VR display device is also described herein. A non-transitory computer-readable storage medium can have an executable program stored thereon that, when executed, instructs a processor to perform the methods described herein.

[0067] In the foregoing description, various examples have been described, which include devices, systems, methods, etc. For purposes of explanation, specific details have been set forth in order to provide a thorough understanding of the examples of the present disclosure. However, it will be apparent that the various examples can be practiced without these specific details. For example, devices, systems, structures, components, methods, and other elements can be shown in block diagram form as components so as not to obscure the examples in unnecessary detail. In other instances, well-known devices, processes, systems, structures, and techniques can be shown without unnecessary detail in order to avoid obscuring these examples.

[0068] The drawings and the specification are not intended to be restrictive. The terms and expressions employed in this disclosure are used as descriptive terms and not of limitation, and in using such terms and expressions, it is not intended to exclude any equivalents of the features shown and described or portions of such features. The word "example" as used herein means "serving as an example, instance, or illustration". Any embodiment or design described herein as an "example" is not necessarily to be construed as preferred or superior to other embodiments or designs.

[0069] Although the methods and systems described herein may be primarily directed to digital content (such as, for example, video or interactive media), it should be understood that the methods and systems described herein may also be used for other types of content or scenarios. Other applications or uses of the methods and systems described herein may also include social networks, marketing, content-based recommendation engines, and / or other types of knowledge or data-driven systems.

Claims

1. An optical component for an augmented reality / virtual reality (AR / VR) display system, the optical component comprising: Reflective polarization volume hologram rPVH layer; Quarter wave plate QWP layer; as well as One or more optical elements, wherein the rPVH layer and the QWP layer are flexible and are applied to one of the one or more optical elements to provide optical power and correct aberrations in the optical assembly.

2. The optical assembly according to claim 1, wherein: The rPVH layer and the QWP layer are used to correct chromatic aberration without introducing negative optical power.

3. The optical assembly according to claim 1, wherein: Compared to the combination of a reflective polarizer and a QWP, the rPVH layer introduces more degrees of freedom for bending light to correct monochromatic aberrations.

4. The optical assembly according to claim 1, wherein: The rPVH layer is sensitive to circular polarization to filter right-hand circular polarization RHCP or left-hand circular polarization LHCP.

5. The optical assembly according to claim 1, wherein: The rPVH layer and the QWP layer are applied to a positive power optical lens by flex lamination.

6. The optical assembly according to claim 1, wherein: The rPVH layer and the QWP layer are applied to a negative power optical lens by flex lamination.

7. The optical assembly according to claim 1, wherein: The rPVH layer comprises liquid crystals LC in a helical twist alignment, wherein the helical axis is perpendicular to the substrate.

8. The optical assembly according to claim 7, wherein: The in-plane periodicity of the rPVH layer is represented as Λx, and the vertical periodicity of the rPVH layer is represented as Λy, where the helical pitch of the rPVH layer is P=2Λy.

9. The optical assembly according to claim 1, wherein: The one or more optical elements of the optical assembly include at least one of an optical lens, an optical filter, or a diffractive optical element (DOE).

10. An augmented reality / virtual reality (AR / VR) near-eye display device, the AR / VR near-eye display device comprising: light source; An optical component, the optical component comprising: Reflective polarization volume hologram rPVH layer; Quarter wave plate QWP layer; and one or more optical elements, wherein the rPVH layer and the QWP layer are flexible and the rPVH layer and the QWP layer are applied to one of the one or more optical elements to provide optical power and correct aberrations in the optical assembly; and A display projects light into the eye zone.

11. The AR / VR near-eye display device according to claim 10, wherein: The light source includes a coherent light source or an incoherent light source.

12. The AR / VR near-eye display device according to claim 10, wherein: The rPVH layer and the QWP layer are used for: Correcting chromatic aberration without introducing negative optical power; and Monochromatic aberrations are corrected by increasing the degrees of freedom for bending light.

13. The AR / VR near-eye display device according to claim 10, wherein: The rPVH layer is sensitive to circular polarization to filter right-hand circular polarization RHCP or left-hand circular polarization LHCP.

14. The AR / VR near-eye display device according to claim 10, wherein: The rPVH layer and the QWP layer are applied to a positive power optical lens by flex lamination.

15. The AR / VR near-eye display device according to claim 10, wherein: The rPVH layer and the QWP layer are applied to a negative power optical lens by flex lamination.

16. The AR / VR near-eye display device according to claim 10, wherein: The rPVH layer comprises liquid crystals LC in a helical twist alignment, wherein the helical axis is perpendicular to the substrate.

17. The AR / VR near-eye display device according to claim 10, wherein: The one or more optical elements of the optical assembly include at least one of an optical lens, an optical filter, or a diffractive optical element (DOE).

18. A method for assembling an augmented reality / virtual reality (AR / VR) near-eye display device, the method comprising: Applying a reflective polarizer volume hologram rPVH layer to a quarter wave plate QWP layer; Adjusting the curvature of the rPVH layer and the QWP layer to match the curvature of an optical element of an optical assembly of the AR / VR near-eye display device; assembling the optical assembly with the rPVH layer, the QWP layer, and one or more optical elements; and Assemble the AR / VR near-eye display device to combine the optical assembly with the light source and one or more additional components.

19. The method according to claim 18, further comprising: The rPVH layer and the QWP layer are applied to the optical element by flex lamination.

20. The method according to claim 19, wherein: The optical element is a positive power optical lens or a negative power optical lens.

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