Extended reality systems and methods

Abstract

Extended reality display systems and methods of manufacturing for improving the compactness and manufacturability of the display system. The display systems include an integral projection lens barrel into which a lens stack is directly loaded. The display systems may also have the illuminator and spatial light modulator on opposite sides of a waveguide which reduces the overall volume of the display system. Embodiments of the displays systems and methods also include the use of structural datums for accurately positioning components of the display systems to improve the manufacturing tolerances of the display systems which ensure that the display systems function at an acceptable optical performance.

Description

EXTENDED REALITY SYSTEMS AND METHODSCross-Reference to Related Applications

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application Serial No. 63 / 619,238, entitled “EXTENDED REALITY SYSTEMS AND METHODS,” and filed on January 9, 2024. The contents of the foregoing application is hereby expressly incorporated by reference for all purposes.Incorporation By Reference

[0002] This application incorporates by reference the entirety of each of the following patent applications: U.S. Utility Patent Application Serial No. 14 / 555,585 filed on November 27, 2014 under attorney docket number ML.20011.00 and entitled “VIRTUAL AND AUGMENTED REALITY SYSTEMS AND METHODS”; U.S. Utility Patent Application Serial No. 14 / 738,877 filed on June 13, 2015 under attorney docket number ML.20019.00 and entitled “METHODS AND SYSTEMS FOR CREATING VIRTUAL AND AUGMENTED REALITY”; U.S. Utility Patent Application Serial No. 15 / 683,677 filed on August 22, 2017 under attorney docket number ML-0341 US and entitled “VIRTUAL, AUGMENTED, and MIXED REALITY SYSTEMS AND METHODS”; and U.S. Utility Patent Application Serial No. 16 / 215,477 filed on December 10, 2018 under attorney docket number 101782-013710US-1347331 and entitled “WAVEGUIDE ILLUMINATOR” and U.S. Provisional Patent Application Serial No. 63 / 503,667 filed on May 22, 2023 under attorney docket number ML-1194USPRV and entitled “EXTENDED REALITY SYSTEMS AND METHODS.”Copyright Notice

[0003] A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.Field of the Invention

[0004] The present disclosure relates to extended reality imaging, visualization, and display systems and methods.Background

[0005] Modem computing and display technologies have facilitated the development of mixed reality systems (“MR”) for so called “virtual reality” or “augmented reality” experiences, wherein digitally reproduced images or portions thereof are presented to a user in a manner wherein they seem to be, or may be perceived as, real. A virtual reality, or “VR”, scenario typically involves presentation of digital or virtual image information without transparency to actual real-world visual input. An augmented reality, or “AR”, scenario typically involves presentation of digital or virtual image information as an augmentation to visualization of the actual world around the user (i.e. , transparency to other actual real-world visual input). Accordingly, AR scenarios involve presentation of digital or virtual image information with transparency to other actual real-world visual input. As used herein, the terms “extended reality” and “XR” are used to refer collectively to any of VR, AR and / or MR. In addition, the term “AR” means either, or both, AR and MR.

[0006] Figure 1 depicts an example XR scene 1 where a user sees a real-world park setting 6 featuring people, trees, buildings in the background, and a concrete platform 20. In addition to these items, computer-generated imagery is also presented to the user. The computer-generated imagery can include, for example, a robot statue 10 standing upon the real-world platform 20, and a cartoon-like avatar character 12 flying by which seems to be a personification of a bumble bee, even though these elements 12, 10 are not actually present in the real-world environment.

[0007] Various optical systems generate images at various depths for displaying XR scenarios. Some such optical systems are described in U.S. Utility Patent Application Serial No. 14 / 555,585, the contents of which have been previously incorporated by reference herein. Other such optical systems for displaying MR experiences are described in U.S. Utility Patent Application Serial No. 14 / 738,877, the contents of which have been previously incorporated by reference herein.

[0008] Because the human visual perception system is complex, it is challenging to produce XR technology that facilitates a comfortable, natural-feeling, rich presentation of virtual image elements amongst other virtual or real-world imagery elements. Improved techniques are needed for processing image data in such systems, including techniques for correcting optical distortions resulting from system component non uniformity. XR technology also has size and portability issues, battery life issues, system over-heating issues, and other system and optical challenges. Improved techniques are needed for addressing these issues, including system temperature management. The systems and methods described herein are configured to address these and other challenges.

[0009] Improved designs and techniques for XR display systems are also needed to improve the compactness of XR display systems and the components thereof to produce a more comfortable and less obtrusive XR experience for the user. Moreover, there is a need for improved designs and assembly techniques for improving the manufacturability and manufacturing tolerances of an XR display system.Summary

[0010] Embodiments disclosed herein are directed to XR display systems and methods of manufacturing XR display systems which improve the compactness of the XR display systems and also improve the manufacturability and manufacturing tolerances of the XR display system. The improved manufacturing tolerances ensure that the display systems function above a minimum optical performance as measurable by key performance indexes (KPIs) of the display system.

[0011] In one embodiment disclosed herein, an XR display system comprises a wearable frame structure configured to be worn on the head of a user. For example, the wearable frame structure may be in the form of eyeglasses. The wearable frame structure includes an eye rim (a monocular display system) or a pair of eye rims (for a binocular display system) for holding the eyepiece(s) through which the user views the images generated by the display system (and in the case of an AR display system, the user also views the surrounding environment through the eyepiece). The XR display system will be further described with respect to a display system (i.e. , a monocular display system) for a single eye with the understanding that a binocular display system includes the same display system for both eyes.

[0012] The wearable frame structure includes a projection lens barrel formed integrally with the frame structure. As used herein, the term “integral” and “integrally” mean that an element is formed monolithically with another element, and that the elements are not separate parts connected to each other by an attachment means such as bonding, welding, fasteners, etc. For instance, the projection lens barrel may be molded or machined into the frame structure. The projection lens barrel extends back from the eye rim such that the projection lens barrel is on the user side of the eye rim. A lens stack for directing light for both illuminating at least a portion of a spatial light modulator (SLM; e.g., a liquid crystal on silicon (LCOS) display) and projecting an image generated by the SLM to the user’s eye is loaded directly into the projection lens barrel. The lens stack is positioned on the user side of the eye rim (and the user side of the eyepiece when inserted into the eye rim). As used herein, the term “user side” means that an element is on the side closer to the user when the display system is worn on the head of the user, and the term “world side” means that an element is on the side away from the user, or toward the surrounding world when the display system is worn on the head of the user. The lens stack comprises a plurality of lenses which stack together to direct light to, and from, the SLM. The integrally formed projection lens barrel eliminates the need for a separate lens barrel housing into which the lens stack is inserted, and then the lens barrel housing and installed lens stack are attached to the frame structure.

[0013] In another aspect, the frame structure is formed of a metal, such as magnesium, aluminum, titanium, an alloy of magnesium, aluminum or titanium, a metal matrix composite (“MMC”), or other suitable metal. In still another aspect, the frame structure may be formed of plastic or polymeric material, including thermoplasticpolymers, thermoset polymers, etc. In the case of a frame structure formed of plastic or polymeric material, the components of the frame structure described as being metallic, such as the bosses on the frame structure, etc., may be formed of a plastic or polymer.

[0014] In another aspect, the lens stack comprises a plurality of glass lenses, instead of the plastic lenses typically used in XR display systems. The glass lenses have a coefficient of thermal expansion (CTE) which more closely matches a metallic frame structure than plastic lenses such that temperature changes of the display system do not cause lens clearance problems with the frame structure at low temperatures. Glass lenses are also not birefringent or hydrophilic, and therefore, temperature changes and moisture do not cause degradation of the optical performance of the display system.

[0015] In another aspect, the display system comprises an illuminator mounted on the world side of the eyepiece. For example, the eyepiece may solely comprise an active waveguide, or the eyepiece may comprise a waveguide enclosed within a protective cover glass. In still another aspect, the illuminator may be mounted directly onto the surface of the world side of the eyepiece, such as directly onto the surface of the world side of the waveguide. In yet another aspect, the SLM is disposed on the user side of the lens stack, such that the SLM is on the user side of the eyepiece while the illuminator is on the world side of the eyepiece.

[0016] In another aspect, the wearable frame structure may include an integrated image sensor (e.g., camera) compartment formed integrally into the frame structure for housing an image sensor and optics (e.g., an imaging lens stack). For example, the image sensor compartment may be similar to the projection barrel and mounting structure for the SLM and illuminator.

[0017] Additional embodiments disclosed herein are directed to features, aspects and methods of manufacture for improving the precision, accuracy, and manufacturability of the display system to ensure that the display system meets the desired optical performance as measured by key performance indexes (KPIs) of the display system. For example, accurate positioning along the optical axis of the display system and orientation of the various components of the display system is required for the optical performance of the display system. If the positioning and orientation of the components is out of tolerance, the optical performance of the display system will be degraded as measured by KPIs of the display system.

[0018] Accordingly, in a first embodiment for improving the positioning tolerances between the lens stack and the waveguide, the frame structure has a plurality of frame datums circumferentially spaced apart around an inside perimeter of the eye rim. The frame datums are configured to accurately locate the waveguide (e.g., the waveguide may solely comprise a stack of active waveguide elements or the waveguide may comprise a stack of active waveguide elements enclosed within cover glass) in the eye rim. In this embodiment, there are two frame datums on the eye rim. The frame datums are configured to accurately position the waveguide within the eye rim. A lens stack datum is disposed on the front side of a lens stack barrel into which a lens stack is inserted. The frame datums and lens stack datum may be precision molded, machined or bonded in place onto the eye rim and lens stack, respectively.

[0019] In order to assemble the lens stack and the waveguide to the frame structure, the frame is installed on an assembly tool having a jig frame datum and a jig lens stack datum such that the frame datums rest on the jig frame datum. Then, the lens stack isinserted into the projection lens barrel of the frame until the lens stack datum rests on the jig lens stack datum which accurately positions and orients the lens stack relative to the frame datums. The lens stack or lens stack assembly is then bonded in place in the projection lens barrel using an adhesive.

[0020] The frame structure and attached lens stack are then removed from the assembly tool and the waveguide is positioned in the eye rim such that the user side surface of the waveguide rests on the two frame datums and the lens stack datum. The waveguide is then bonded in place in the eye rim using an adhesive. In one aspect, the waveguide may be tacked in place using a tacking adhesive. Then, a perimeter bond is applied around the perimeter of the waveguide to firmly bond and seal the waveguide into the eye rim. It is understood that the same procedure can be performed to assemble the waveguide and lens stack for both sides of a binocular display system.

[0021] A second embodiment for improving the positioning tolerances between the lens stack and the waveguide disclosed herein is similar to the first embodiment except that all three of the positioning datums for the waveguide are located on the eye rim and the position of the lens stack is set by a lens datum precision machined or molded into the frame structure instead of the lens datum on the lens stack. The frame structure has three frame datums circumferentially spaced apart around an inside perimeter of the eye rim. The three frame datums are configured to accurately locate the waveguide. The frame datums may be precision molded, machined or bonded (e.g., glued, welded, soldered, etc.) in place onto the eye rim. The lens datum comprises one or more precision machined or molded bosses positioned at the front of the projection lens barrel of the frame structure.

[0022] In this second embodiment, the assembly of the lens stack and the waveguide onto the frame structure does not require an assembly tool. The lens stack is simply inserted into the projection lens barrel of the frame structure until the lens stack bears against the lens datum. The lens stack is then bonded in place using an adhesive. The waveguide is then inserted into the eye rim with the surface of user side of the waveguide bearing against all three of the frame datums. The waveguide is bonded in place in the eye rim using an adhesive. In one aspect, the waveguide may be tacked in place using a tacking adhesive. Then, a perimeter bond is applied around the perimeter of the waveguide to firmly bond and seal the waveguide into the eye rim. It is understood that the same procedure can be performed to assemble the waveguide and lens stack for both sides of a binocular display system. Again, It is understood that the same procedure can be performed to assemble the waveguide and lens stack for both sides of a binocular display system.

[0023] A third embodiment for improving the positioning tolerances between the lens stack and the waveguide disclosed herein is similar to the second embodiment except that the three frame datums on the eye rim are separate elements positioned on the eye rim using an assembly tool having a plurality of jigs for accurately position the frame on tool and for setting the position of the frame datums. In another aspect, the jigs may comprise pins, posts, control surfaces, etc. The frame structure is positioned on the assembly tool using a frame jig to accurately position the frame structure in the X-Y coordinates and the pitch and yaw angle. Each of the three frame datums are positioned around the eye rim by a respective frame datum jig, such as a positioning post or the like. Each frame datum jig is configured to accurately position a respective frame datum. Oncepositioned by the respective frame datum jig, each frame datum is bonded in place on the eye rim using an adhesive bond. In one aspect, each frame datums may comprise a puck, such as a plastic / polymer puck or other suitable device for setting the position of the waveguide.

[0024] In another aspect, the eye rim may have three frame datum holder positioned on the eye rim in the position for placing the frame datums on the eye rim. In yet another aspect, the frame datum holders are bosses molded or machined into the frame structure and configured to adjustably receive and retain in place a respective frame datum. In such case, each frame datum jig is installed in a respective frame datum holder until the frame datum bears against the respective frame datum, and then each frame datum is bonded to the respective frame datum holder.

[0025] Once the frame datums are installed on the eye rim, the assembly of the waveguide and lens stack onto the frame structure according to this third embodiment is the same as for the second embodiment described above.

[0026] Another embodiment disclosed herein is directed to features, aspects, and methods of manufacture for improving the precision, accuracy and manufacturability of the interface between the illuminator and the waveguide. In this embodiment, the illuminator is directly bonded to the world side surface of the waveguide. The illuminator has an illuminator base having three illuminator datums on the bottom of the base. In one aspect, the illuminator datums are molded into the base, or they may be separate pucks attached to the base. The illuminator is attached directly to the waveguide by applying adhesive around the edge of the bottom of the illuminator base between the illuminator datums. The illuminator is then placed directly onto the waveguide with the illuminatordatums directly contacting the surface of the world side of the waveguide. The illuminator datums precisely control the Z-position and pitch and yaw of the illuminator relative to the waveguide, which also accurately positions the illuminator relative to the rest of the display assembly.

[0027] In other aspect, the illuminator may be attached to the waveguide before, or after, the waveguide is attached to the eye rim of the frame structure. Directly bonding the illuminator to the waveguide reduces the volume of the laminator by eliminating the extra structure (e.g., flanges, bosses or the like) needed to attach the illuminator to the eye rim. In addition, directly bonding the illuminator to the waveguide and the use of illuminator datums improves the accuracy (i.e. , reduces the tolerances) of the Z-position and pitch and yaw between the illuminator and the waveguide because it eliminates stacking of the tolerances between the illuminator, the eye rim, the waveguide and the adhesive joints between each of these elements.

[0028] The aforementioned and other embodiments of the invention are described in the Detailed Description which follows.Brief Description of the Drawings

[0029] This patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawings will be provided by the U.S. Patent and Trademark Office upon request and payment of the necessary fee.

[0030] The drawings described below are for illustration purposes only. The drawings are not intended to limit the scope of the present disclosure.

[0031] The drawings illustrate the design and utility of various embodiments of the present disclosure. It should be noted that the figures are not drawn to scale and that elements of similar structures or functions are represented by like reference numerals throughout the figures. In order to better appreciate how to obtain the recited and other advantages and objects of various embodiments of the disclosure, a more detailed description of the present disclosure will be rendered by reference to specific embodiments thereof, which are illustrated in the accompanying drawings. Understanding that these drawings depict only typical embodiments of the disclosure and are not therefore to be considered limiting of its scope, the disclosure will be described and explained with additional specificity and detail through the use of the accompanying drawings.

[0032] Figure 1 depicts a user’s view of an XR scene using an exemplary XR system, according to some embodiments.

[0033] Figure 2 depicts an example of wearable display system, according to some embodiments.

[0034] Figure 3 is a block diagram depicting an AR / MR / XR system, according to some embodiments.

[0035] Figure 4A depicts a conventional display system for simulating three- dimensional imagery for a user.

[0036] Figure 4B depicts aspects of an approach for simulating three-dimensional imagery using multiple depth planes, according to some embodiments.

[0037] Figures 5A-5C depict relationships between radius of curvature and focal radius.

[0038] Figure 6 depicts an example of a waveguide stack for outputting image information to a user, according to some embodiments.

[0039] Figure 7 depicts an example of exit beams outputted by a waveguide, according to some embodiments.

[0040] Figure 8 depicts an example design of a waveguide stack in which each depth plane has three associated waveguides that each output light of a different color, according to some embodiments.

[0041] Figure 9 schematically depicts a display system for presenting images to a user’s eye, and for viewing the world, according to some embodiments.

[0042] Figures 10A-1 OD-2 depict a prior art display system for presenting images to a user’s eye and for viewing the world.

[0043] Figure 11 schematically depicts a display system having a plurality of LED arrays forming a Lambertian light source, according to some embodiments.

[0044] Figures 12A-12J illustrate an improved display system and improved method of manufacturing the same, according to some embodiments.

[0045] Figures 13A-13B illustrate another improved display system and improved method of manufacturing the same, according to some embodiments.

[0046] Figures 14A-14D illustrate another improved display system and improved method of manufacturing the same, according to some embodiments.

[0047] Figures 15A-15D illustrate another improved display system and improved method of manufacturing the same, according to some embodiments.

[0048] Figures 16A-16D illustrate another improved display system and improved method of manufacturing the same, according to some embodiments.

[0049] Figures 17A-17E illustrate another improved display system and improved method of manufacturing the same, according to some embodiments.Detailed Description

[0050] Various embodiments of the disclosure are directed to systems, methods of manufacture, and articles of manufacture for XR in a single embodiment or in multiple embodiments. Other objects, features, and advantages of the disclosure are described in the detailed description, figures, and claims.

[0051] Various embodiments will now be described in detail with reference to the drawings, which are provided as illustrative examples so as to enable those skilled in the art to practice the disclosure. Notably, the figures and the examples below are not meant to limit the scope of the present disclosure. Where certain elements of the present disclosure may be partially or fully implemented using known components (or methods or processes), only those portions of such known components (or methods or processes) that are necessary for an understanding of the present disclosure will be described, and the detailed descriptions of other portions of such known components (or methods or processes) will be omitted so as not to obscure the disclosure. Further, various embodiments encompass present and future known equivalents to the components referred to herein by way of illustration.

[0052] Some embodiments are directed to approaches for adding capabilities and / or repurposing resources to accommodate the desired features or performance characteristics of the to-be-deployed VR / AR / MR / XR system. The accompanying figures and discussions herein present example environments, systems, methods, and computer program products for VR / AR / MR / XR systems.Overview

[0053] XR systems disclosed herein can include a display which presents computergenerated imagery (video / image data) to a user. In some embodiments, the display systems are wearable, which may advantageously provide a more immersive XR experience. Figure 2 illustrates an example of wearable XR display system 80 (hereinafter referred to as “display system 80”) which comprises a headset mounted display system 80. The display system 80 includes a wearable support structure comprising a frame structure 64 configured to be worn on the head of a user 60, similar to an eyeglasses frame. The frame structure 64 include a pair of eye rims 82 including a left eye rim 82a and a right eye rim 82b, and a pair of temples 84 including a left temple 84a and a right temple (not shown in Figure 2), extending from the temple portion of each respective eye rim 82. The display system 80 is not required to be a wearable system, but instead may include a separate display which may be a portable monitor, table-top monitor, tablet computer, smartphone or the like. However, a wearable system has the advantage of allowing the user to keep his / her hands free while using the display system 80, and in the case of a headset, provides an immersive XR experience.

[0054] The display system 80 includes a display 62, and various mechanical and electronic modules and systems to support the functioning of the display 62. The display 62 is coupled to the frame structure 64 and which is configured to position the display 62 in front of the eyes of the user 60. In some embodiments, a speaker 66 is coupled to the frame structure 64 and positioned adjacent the ear canal of the user 60. In some embodiments, another speaker, not shown, is positioned adjacent the other ear canal of the user 60 to provide for stereo / shapeable sound control. The display 62 isoperatively coupled, such as by a wired or wireless connection 68, to a local processing and data module 70 which may be mounted in a variety of configurations, such as fixedly attached to the frame 64, fixedly attached to a helmet or hat worn by the user, embedded in headphones, or otherwise removably attached to the user 60 (e.g., in a backpack-style configuration, in a belt-coupling style configuration, etc.).

[0055] The local processing and data module 70 may include a processor, as well as digital memory, such as non-volatile memory (e.g., flash memory), both of which may be utilized to assist in the processing and storing of data. This includes data captured from sensors, such as ambient light sensors (“ALS”), image capture devices (e.g., cameras), microphones, inertial measurement units, accelerometers, compasses, GPS units, radio devices, antenna arrays, depth sensors, and / or gyros. An ALS may be configured to provide light data for processors and algorithms for segmented illumination / dimming brightness control. The sensors may be operatively coupled to the frame structure 64 or otherwise attached to the user 60. Alternatively, or additionally, sensor data may be acquired and / or processed using a remote processing module 72 and / or a remote data repository 74, possibly for passage to the display 62 after such processing or retrieval. The local processing and data module 70 may be operatively coupled by communication links (76, 78), such as via a wired or wireless communication links, to the remote processing module 72 and remote data repository 74 such that these remote modules (72, 74) are operatively coupled to each other and available as resources to the local processing and data module 70.

[0056] In some embodiments, the remote processing module 72 may include one or more processors configured to analyze and process data (e.g., sensor data and / or imageinformation). In some embodiments, the remote data repository 74 may include a digital data storage facility, which may be available through the internet or other networking configuration in a “cloud” resource configuration. In some embodiments, all data is stored and all computations are performed in the local processing and data module, allowing fully autonomous use from a remote module.

[0057] In some embodiments, the computer-generated image data provided via the display 62 can create the impression of being three-dimensional. This can be done, for example, by presenting stereoscopic image data to the user 60. In some conventional systems, such image data can include separate images of a scene or object from slightly different perspectives. The separate images can be presented to the right eye and left eye of the user 60 respectively, thus simulating binocular vision and its associated depth perception.

[0058] Referring now to Figure 3, an exemplary embodiment of an XR system 3300 (hereinafter referred to as “system 3300”) is illustrated. The system 3300 uses stacked light guiding optical element (hereinafter referred to as ““LOEs 3390”). The system 3300 generally includes an image generating processor 3310, a light source 3320 (however, not all XR display systems require a light source), a controller / driver 3330, a spatial light modulator (“SLM”) 3340, and at least one set of stacked LOEs 3390 that functions as a multiple plane focus system. The system 3300 may also include an eye-tracking subsystem 3350. It should be appreciated that other embodiments may have multiple sets of stacked LOEs 3390.

[0059] The image generating processor 3310 is configured to generate virtual content to be displayed to the user. The image generating processor 3310 may convert an imageor video associated with the virtual content to a format that can be projected to the user in 3D. For example, in generating 3D content, the virtual content may need to be formatted such that portions of a particular image are displayed at a particular depth plane while others are displayed at other depth planes. In one embodiment, all of the image may be generated at a particular depth plane. In another embodiment, the image generating processor 3310 may be programmed to provide slightly different images to the right and left eyes such that when viewed together, the virtual content appears coherent and comfortable to the user’s eyes.

[0060] The image generating processor 3310 may further include a memory 3312, a GPU 3314, a CPU 3316, and other circuitry for image generation and processing. The image generating processor 3310 may be programmed with the desired virtual content to be presented to the user of the system 3300. It should be appreciated that in some embodiments, the image generating processor 3310 may be housed in the system 3300. In other embodiments, the image generating processor 3310 and other circuitry may be housed in a belt pack that is coupled to the system 3300.

[0061] The image generating processor 3310 is operatively coupled to the light source 3320 (if the system 3300 includes a light source) which projects light associated with the desired virtual content and one or more spatial light modulators 3340. The image generating processor 3310 and / or the controller / driver 3330 may also calibrate and correct for system nonuniformities. For example, EP nonuniformities or segmented illumination nonuniformities, which result from exposure to high temperatures and aging. The image generating processor 3310 may also warp / transform images with low latenciesto account for user motions. This warp / transform can also be applied to the segmented illumination. The light source 3320 is compact and has high resolution.

[0062] The light source 3320 is operatively coupled to the controller / driver 3330. The light source 3320 may be connected to the controller / driver 3330 in various embodiments. In some embodiments, the light source 3320 and the controller / driver 3330 are co-located on the same board. Those versed in the art would appreciate the value of minimizing the effect of cable inductance and capacitance by co-locating light sources to “driver” electronics. Minimizing the impact of coupled inductance and capacitance by co-locating the light source 3320 and the controller / driver 3330 facilitates faster transition (i.e. , “ON” to “OFF” and all the intervening dimming levels) of the light source 3320. In embodiments in which the light source 3320 and the controller / driver 3330 are located farther away from each other, the stray inductance and capacitance resulting from the increased distance between the light source 3320 and the controller / driver 3330 may be managed by proper cable construction, such as that used in a Flex cable, which can provide shielding.

[0063] The light source 3320 is coupled to the controller / driver 3330 electrically to allow the controller / driver 3330 to drive the segmented illumination segments. The controller / driver 3330 can also connect to both the image generating processor 3310 and the SLM 3340 electrically to facilitate coordinated control. The image generating processor 3310 may send the processed illumination array data (gray values for each color) to the controller / driver 3330. The SLM 3340 may send timing signals to the controller / driver 3330 to facilitate the segmented illumination at the appropriate time(s). In some embodiments, electronically connecting the controller / driver 3330 to the SLM3340 enables the light source 3320 to emit the correct LED colors when the SLM 3340 is refreshing a color field for a field sequential display system.

[0064] The light source 3320 may be include color specific light emitting diodes (“LEDs”) disposed in various geometric configurations. Alternatively, the light source 3320 may include LEDs of like color, each one linked to a specific region of the field of view of the display. In some embodiments, the light source 3320 may include mini LEDs, micro LEDs, laser diodes, phosphor converted LED sources, vertical-cavity surfaceemitting laser (“VSCELs”), and / or super luminescent diodes (“SLDs”). In some embodiments, the light source 3320 may include a mask overlay for segmentation of emission areas and positions. Although the light source 3320 is directly connected to the system 3300 in Figure 3, the light source 3320 may be connected to the system 3300 via optical fibers (not shown). The system 3300 may also include condenser (not shown) configured to collimate the light from the light source 3320.

[0065] The SLM 3340 may be reflective (e.g., an LCDS, an FLCOS, a DLP DMD, or a MEMS mirror system) or transmissive (e.g., an LCD) in various exemplary embodiments. The type of SLM 3340 (e.g., speed, size, etc.) can be selected to improve the creation of the 3D perception. While DLP DMDs operating at higher refresh rates may be easily incorporated into stationary systems 3300, wearable systems 3300 may use DLPs of smaller size and power. The power of the DLP changes how 3D depth planes / focal planes are created. The image generating processor 3310 is operatively coupled to the SLM 3340, which encodes the light from the light source 3320 with the desired virtual content. Light from the light source 3320 may be encoded with the image information when it reflects off of, emits from, or passes through the SLM 3340.

[0066] Light from the SLM 3340 is directed to the LOEs 3390 such that light beams encoded with image data for one depth plane and / or color by the SLM 3340 are effectively propagated along a single LOE 3390 for delivery to an eye of a user. Each LOE 3390 is configured to project an image or sub-image that appears to originate from a desired depth plane or FOV angular position onto a user’s retina. The light source 3320 and LOEs 3390 can therefore selectively project images (synchronously encoded by the SLM 3340 under the control of controller / driver 3330) that appear to originate from various depth planes or positions in space. By sequentially projecting images using each of the light source 3320 and LOEs 3390 at a sufficiently high frame rate (e.g., 360 Hz for six depth planes at an effective full-volume frame rate of 60 Hz), the system 3300 can generate a 3D image of virtual objects at various depth planes that appear to exist simultaneously in the 3D image.

[0067] The controller / driver 3330 is in communication with and operatively coupled to the image generating processor 3310, the light source 3320 and the SLM 3340 to coordinate the synchronous display of images by instructing the SLM 3340 to encode the light beams from the light source 3320 with appropriate image information from the image generating processor 3310.

[0068] The system 3300 also includes an optional eye-tracking subsystem 3350 that is configured to track the user’s eyes and determine the user’s focus. In one embodiment, the system 3300 is configured to illuminate a subset of LOEs 3390, based on input from the eye-tracking subsystem 3350 such that the image is generated at a desired depth plane that coincides with the user’s focus / accommodation. For example, if the user’s eyes are parallel to each other, the system 3300 may illuminate the LOE 3390 that isconfigured to deliver collimated light to the user’s eyes, such that the image appears to originate from optical infinity. In another example, if the eye-tracking subsystem 3350 determines that the user’s focus is at 1 meter away, the LOE 3390 that is configured to focus approximately within that range may be illuminated instead.

[0069] Figure 4A illustrates a conventional display system for simulating three- dimensional image data to a user (e.g., the user 60). Two distinct images 84 and 86, one for each eye 4 and 5, are outputted to the user. The images 84 and 86 are spaced from the eyes 4 and 5 by a distance 12 along an optical or z-axis parallel to the line of sight of the user 60. The images 84 and 86 are flat and the eyes 4 and 5 may focus on the images by assuming a single accommodated state. Such systems rely on the human visual system to combine the images 84 and 86 to provide a perception of depth for the combined image.

[0070] It will be appreciated, however, that the human visual system is more complicated and providing a realistic perception of depth is more challenging. For example, many users of conventional 3D display systems find such systems to be uncomfortable or may not perceive a sense of depth at all. Without being limited by theory, it is believed that users viewing an object may perceive the object as being “three- dimensional” due to a combination of vergence and accommodation. Vergence movements (i.e., rolling movements of the pupils toward or away from each other to converge the lines of sight of the eyes to fixate upon an object) of the two eyes relative to each other are closely associated with focusing (or “accommodation”) of the lenses of the eyes. Under normal conditions, changing the focus of the lenses of the eyes, or accommodating the eyes, to change focus from one object to another object at a differentdistance will automatically cause a matching change in vergence to the same distance, under a relationship known as the “accommodation-vergence reflex.” Likewise, a change in vergence will trigger a matching change in accommodation, under normal conditions. As noted herein, many stereoscopic display systems display a scene using slightly different presentations (and, so, slightly different images) to each eye such that a three- dimensional perspective is perceived by the human visual system. Such systems are uncomfortable for many users since they simply provide different presentations of a scene but with the eyes viewing all the image information at a single accommodated state, and thus work against the accommodation-vergence reflex. Systems that provide a better match between accommodation and vergence may form more realistic and comfortable simulations of three-dimensional image data.

[0071] For example, light field video data can be presented to the user to simulate a three-dimensional view. Light field video data can mimic the rays of light which enter the eyes of the user in a real-world environment. For example, when displaying light field video data, light rays from objects that are simulated to be perceived at a distance are made to be more collimated when entering the eyes of the user, while light rays from objects that are simulated to be perceived nearby are made to be more divergent. Thus, the angles at which light rays from objects in a scene enter the eyes of the user are dependent upon the simulated distance of those objects from the viewer. Light field video data in a VR / AR / MR / XR system can include multiple images of a scene or object from different depth planes. The images may be different for each depth plane (e.g., one depth plane may include imagery corresponding to the foreground of a scene, while another depth plane includes imagery corresponding to the background of the scene) and may beseparately focused by the viewer’s eyes, thereby helping to provide the user with a comfortable perception of depth.

[0072] When these multiple depth plane images are presented to the viewer simultaneously or in quick succession, the result is interpreted by the viewer as three- dimensional imagery. When the viewer experiences this type of light field video data, the eyes accommodate to focus the different depth planes in much the same way as they would do when experiencing a real-world scene. These focal cues can provide for a more realistic simulated three-dimensional environment.

[0073] In some configurations, at each depth plane, a full color image may be formed by overlaying component images that each have a particular component color. For example, red, green, and blue images may each be separately outputted to form each full color depth plane image. As a result, each depth plane may have multiple component color images associated with it.

[0074] Figure 4B illustrates aspects of an approach for simulating three-dimensional imagery using multiple depth planes. Objects at various distances from eyes 4 and 5 on the z-axis are accommodated by the eyes (4, 5) so that those objects are in focus. The eyes 4 and 5 assume particular accommodated states to bring into focus objects at different distances along the z-axis. Consequently, a particular accommodated state may be said to be associated with a particular one of depth planes 14, such that objects or parts of objects in a particular depth plane are in focus when the eye is in the accommodated state for that depth plane. In some embodiments, three-dimensional image data may be simulated by providing different presentations of the image data foreach of the eyes (4, 5), and also by providing different presentations of the image data corresponding to each of the depth planes.

[0075] The distance between an object and the eye (4 or 5) can change the amount of divergence of light from that object, as viewed by that eye. Figures 5A-5C illustrate relationships between distance and the divergence of light rays. The distance between the object and the eye 4 is represented by, in order of decreasing distance, R1 , R2, and R3. As shown in Figures 5A-5C, the light rays become more divergent as distance from the eye 4 to the object decreases. As distance from the eye 4 to the object increases, the light rays become more collimated. Stated another way, it may be said that the light field produced by a point (the object or a part of the object) has a spherical wavefront curvature, which is a function of how far away the point is from the eye 4 of the user. The curvature increases with decreasing distance between the object and the eye 4. Consequently, at different depth planes, the degree of divergence of light rays is also different, with the degree of divergence increasing with decreasing distance between depth planes and the eye 4. While only a single eye 4 is illustrated for clarity of illustration in Figures 5A-5C and other figures herein, it will be appreciated that the discussions regarding eye 4 may be applied to both eyes (4 and 6) of a viewer.

[0076] Without being limited by theory, it is believed that the human eye typically can interpret a finite number of depth planes to provide depth perception. Consequently, a highly believable simulation of perceived depth may be achieved by providing, to the eye, different presentations of image data corresponding to each of these limited number of depth planes.

[0077] Alternative to using multiple depth planes, they system 3300 may simulate three-dimensional imagery using optics which project the images in infinity. The optics may include a rear extended depth-of-focus (“EDOF”) lens to change the images from infinity to 0.74 m.

[0078] Figure 6 illustrates an example of a waveguide stack for outputting image data to a user (e.g., the user 60). A display system 1000 includes a stack of waveguides, or stacked waveguide assembly 178, that may be utilized to provide three-dimensional perception to the eye / brain using one or more waveguides (182, 184, 186, 188, 190). In some embodiments, the display system 1000 is the system 80 of Figure 2, with Figure 6 schematically showing some parts of the system 80 in greater detail. For example, the stacked waveguide assembly 178 may be integrated into the display 62 of Figure 2.

[0079] The stacked waveguide assembly 178 may also include one or more features (198, 196, 194, 192) between the waveguides. In some embodiments, the features (198, 196, 194, 192) may be lenses. The waveguides (182, 184, 186, 188, 190) and / or the lenses (198, 196, 194, 192) may be configured to send image data to the eye with various levels of wavefront curvature or light ray divergence. Each waveguide level may be associated with a particular depth plane and may be configured to output image data corresponding to that depth plane. Image injection devices (200, 202, 204, 206, 208) may be utilized to inject image data into the waveguides (182, 184, 186, 188, 190), each of which may be configured, as described herein, to distribute incoming light across each respective waveguide, for output toward the eye 4. Light exits an output surface (300, 302, 304, 306, 308) of the image injection devices (200, 202, 204, 206, 208) and is injected into a corresponding input edge (382, 384, 386, 388, 390) of the waveguides(182, 184, 186, 188, 190). In some embodiments, a single beam of light (e g., a collimated beam) may be injected into each waveguide to output an entire field of cloned collimated beams that are directed toward the eye 4 at particular angles (and amounts of divergence) corresponding to the depth plane associated with a particular waveguide.

[0080] In some embodiments, the image injection devices (200, 202, 204, 206, 208) are discrete displays that each produce image data for injection into a corresponding waveguide (182, 184, 186, 188, 190, respectively). In some other embodiments, the image injection devices (200, 202, 204, 206, 208) are the output ends of a single multiplexed display which may pipe image data via one or more optical conduits (such as fiber optic cables) to each of the image injection devices (200, 202, 204, 206, 208).

[0081] A controller 210 controls the operation of the stacked waveguide assembly 178 and the image injection devices (200, 202, 204, 206, 208). In some embodiments, the controller 210 includes programming (e.g., instructions in a non-transitory computer- readable medium) that regulates the timing and provision of image data to the waveguides (182, 184, 186, 188, 190) according to any of the various schemes disclosed herein. In some embodiments, the controller 210 may be a single integral device, or a distributed system connected by wired or wireless communication channels. The controller 210 may be part of a processing module (e.g., the local processing and data module 70 and / or the remote processing module 72 of Figure 2) in some embodiments.

[0082] The waveguides (182, 184, 186, 188, 190) may be configured to propagate light within each respective waveguide by total internal reflection (TIR). The waveguides (182, 184, 186, 188, 190) may each be planar or curved, with major top and bottom surfaces and edges extending between those major top and bottom surfaces. In theillustrated configuration, the waveguides (182, 184, 186, 188, 190) may each include light redirecting elements (282, 284, 286, 288, 290) that are configured to redirect light, propagating within each respective waveguide, out of the waveguide to output image data to the eye 4. A beam of light is outputted by the waveguide at locations at which the light propagating in the waveguide strikes a light redirecting element. The light redirecting elements (282, 284, 286, 288, 290) may be reflective and / or diffractive optical features. While illustrated disposed at the bottom major surfaces of the waveguides (182, 184, 186, 188, 190) for ease of description and drawing clarity, in some embodiments, the light redirecting elements (282, 284, 286, 288, 290) may be disposed at the top and / or bottom major surfaces, and / or may be disposed directly in the volume of the waveguides (182, 184, 186, 188, 190). In some embodiments, the light redirecting elements (282, 284, 286, 288, 290) may be formed in a layer of material that is attached to a transparent substrate to form the waveguides (182, 184, 186, 188, 190). In some other embodiments, the waveguides (182, 184, 186, 188, 190) may be a monolithic piece of material and the light redirecting elements (282, 284, 286, 288, 290) may be formed on a surface and / or in the interior of that piece of material.

[0083] As discussed herein, each waveguide (182, 184, 186, 188, 190) is configured to output light to form an image corresponding to a particular depth plane. For example, the waveguide 182 nearest the eye 4 may be configured to deliver collimated light, as injected into such waveguide 182, to the eye 4. The collimated light may be representative of the optical infinity focal plane. The next waveguide up 184 may be configured to send out collimated light which passes through the first lens 192 (e.g., a negative lens) before it can reach the eye 4. The first lens 192 may be configured tocreate a slight convex wavefront curvature so that the eye / brain interprets light coming from that next waveguide up 184 as coming from a first focal plane closer inward toward the eye 4 from optical infinity. Similarly, the third waveguide up 186 passes its output light through both the first lens 192 and second lens 194 before reaching the eye 4; the combined optical power of the first lens 192 and second lens 194 may be configured to create another incremental amount of wavefront curvature so that the eye / brain interprets light coming from the third waveguide 186 as coming from a second focal plane that is even closer inward toward the user from optical infinity than was light from the next waveguide up 184. Alternatively, the waveguide grating pattern may light in infinity and not to a particular depth plane, and may use the EDOF lens to make the images appear at a desired depth plane (e.g., 0.74 m).

[0084] The other waveguides (188, 190) and lenses (196, 198) are similarly configured, with the highest waveguide 190 in the stack sending its output through all of the lenses between it and the eye for an aggregate focal power representative of the closest focal plane to the user. To compensate for the stack of lenses (198, 196, 194, 192) when viewing / interpreting light coming from world 144 on the other side of the stacked waveguide assembly 178, a compensating lens layer 180 may be disposed at the top of the stacked waveguide assembly 178 to compensate for the aggregate power of the lens stack (198, 196, 194, 192) below. Such a configuration provides as many perceived focal planes as there are available waveguide / lens pairings. Both the light redirecting elements of the waveguides and the focusing aspects of the lenses may be static (i.e., not dynamic or electro-active). In some alternative embodiments, they may be dynamic using electro-active features.

[0085] The light redirecting elements (282, 284, 286, 288, 290) may be configured to both redirect light out of their respective waveguides and to output this light with the appropriate amount of divergence or collimation for a particular depth plane associated with the waveguide. As a result, waveguides having different associated depth planes may have different configurations of light redirecting elements (282, 284, 286, 288, 290), which output light with a different amount of divergence depending on the associated depth plane. In some embodiments, as discussed herein, the light redirecting elements (282, 284, 286, 288, 290) may be volumetric or surface features, which may be configured to output light at specific angles. For example, the light redirecting elements (282, 284, 286, 288, 290) may be volume holograms, surface holograms, and / or diffraction gratings. Light redirecting elements, such as diffraction gratings, are described in U.S. Patent Application No. 14 / 641 ,376, filed March 7, 2015, which is incorporated by reference herein in its entirety. In some embodiments, the features (198, 196, 194, 192) may not be lenses; rather, they may simply be spacers (e.g., cladding layers and / or structures for forming air gaps).

[0086] In some embodiments, the light redirecting elements (282, 284, 286, 288, 290) are diffractive features that form a diffraction pattern, or “diffractive optical element” (also referred to herein as a “DOE”). Preferably, the DOE’s have a relatively low diffraction efficiency so that only a portion of the light of the beam is deflected away toward the eye 4 with each intersection of the DOE, while the rest continues to move through a waveguide via total internal reflection. The light carrying the image data is thus divided into a number of related exit beams that exit the waveguide at a multiplicity of locationsand the result is a fairly uniform pattern of exit emission toward the eye 4 for this particular collimated beam reflecting around within a waveguide.

[0087] In some embodiments, one or more DOEs may be switchable between “on” states in which they actively diffract, and “off” states in which they do not significantly diffract. For instance, a switchable DOE may include a layer of polymer dispersed liquid crystal, in which microdroplets include a diffraction pattern in a host medium, and the refractive index of the microdroplets can be switched to substantially match the refractive index of the host material (in which case the pattern does not appreciably diffract incident light) or the microdroplet can be switched to an index that does not match that of the host medium (in which case the pattern actively diffracts incident light).

[0088] Figure 7 shows an example of exit beams outputted by a waveguide. One waveguide is illustrated, but it will be appreciated that other waveguides in the stacked waveguide assembly 178 may function similarly. Light 400 is injected into the waveguide 182 at the input edge 382 of the waveguide 182 and propagates within the waveguide 182 by TIR. At points where the light 400 impinges on the DOE 282, a portion of the light exits the waveguide as exit beams 402. The exit beams 402 are illustrated as substantially parallel but, as discussed herein, they may also be redirected to propagate to the eye 4 at an angle (e.g., forming divergent exit beams), depending on the depth plane associated with the waveguide 182. It will be appreciated that substantially parallel exit beams may be indicative of a waveguide that corresponds to a depth plane at a large simulated distance (e.g., optical infinity) from the eye 4. Other waveguides may output an exit beam pattern that is more divergent, which would require the eye 4 toaccommodate to focus on a closer simulated distance and would be interpreted by the brain as light from a distance closer to the eye 4 than optical infinity.

[0089] Figure 8 schematically illustrates an example design of a stacked waveguide assembly (e.g., the stacked waveguide assembly 178) in which each depth plane has three associated waveguides that each output light of a different color. A full color image may be formed at each depth plane by overlaying images in each of multiple component colors (e.g., three or more component colors). In some embodiments, the component colors include red, green, and blue. In some other embodiments, other colors, including magenta, yellow, and cyan, may be used in conjunction with or may replace one of red, green, or blue. Each waveguide may be configured to output a particular component color and, consequently, each depth plane may have multiple waveguides associated with it. Each depth plane may have three waveguides associated with it: a first for outputting red light, a second for outputting green light, and a third for outputting blue light. Alternatively, a single plane waveguide may be configured to transmit multiple colors. For example, a single plane waveguide may transmit two colors (e.g., green / blue) or three colors, within only one plane.

[0090] Depth planes 14a-14f are shown in Figure 8. In the illustrated embodiment, each depth plane has three component color images associated with it: a first image of a first color, G; a second image of a second color, R; and a third image of a third color, B. The numbers following each of these letters indicate diopters (1 / m), or the reciprocal of the apparent distance of the depth plane from a viewer, and each box in the figures represents an individual component color image. In some embodiments, G is the color green, R is the color red, and B is the color blue. As discussed above, the perceiveddistance of the depth plane from the user may be established by the light redirecting elements (282, 284, 286, 288, 290) (e.g., diffractive optical element (DOE), and / or by lenses (198, 196, 194, 192)) which cause the light to diverge at an angle associated with the apparent distance.

[0091] In some arrangements, each component color image may be outputted by a different waveguide in a stack of waveguides. For example, each depth plane may have three component color images associated with it: a first waveguide to output a first color, G; a second waveguide to output a second color, R; and a third waveguide to output a third color, B. In arrangements in which waveguides are used to output component color images, each box in Figure 8 may be understood to represent an individual waveguide.

[0092] While the waveguides associated with each depth plane are shown adjacent to one another in this schematic drawing for ease of description, it will be appreciated that, in a physical device, the waveguides may all be arranged in a stack with one waveguide per level. Different depth planes are indicated in the figure by different numbers for diopters following the letters G, R, and B.Definitions and Use of Figures

[0093] Some of the terms used in this description are defined below for reference. The presented terms and their respective definitions are not rigidly restricted to these definitions — a term may be further defined by the term’s use within this disclosure. The term “exemplary” is used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects or designs. Rather, use of the word exemplary is intended to present concepts in a concrete fashion. As used in thisapplication and the appended claims, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or”. That is, unless specified otherwise, or is clear from the context, “X employs A or B” is intended to mean any of the natural inclusive permutations. That is, if X employs A, X employs B, or X employs both A and B, then “X employs A or B” is satisfied under any of the foregoing instances. As used herein, at least one of A or B means at least one of A, or at least one of B, or at least one of both A and B. In other words, this phrase is disjunctive. The articles “a” and “an” as used in this application and the appended claims should generally be construed to mean “one or more” unless specified otherwise or is clear from the context to be directed to a singular form.

[0094] Various embodiments are described herein with reference to the figures. It should be noted that the figures are not necessarily drawn to scale and that elements of similar structures or functions are sometimes represented by like reference characters throughout the figures. It should also be noted that the figures are only intended to facilitate the description of the disclosed embodiments — they are not representative of an exhaustive treatment of all possible embodiments, and they are not intended to impute any limitation as to the scope of the claims. In addition, an illustrated embodiment need not portray all aspects or advantages of usage in any particular environment.

[0095] An aspect or an advantage described in conjunction with a particular embodiment is not necessarily limited to that embodiment and can be practiced in any other embodiments even if not so illustrated. References throughout this specification to “some embodiments” or “other embodiments” refer to a particular feature, structure, material or characteristic described in connection with the embodiments as being included in at least one embodiment. Thus, the appearance of the phrases “in some embodiments”or “in other embodiments” in various places throughout this specification are not necessarily referring to the same embodiment or embodiments. The disclosed embodiments are not intended to be limiting of the claims.Optical Distortion CorrectionExemplary Segmented Illumination / Dimming Display Systems

[0096] Figure 9 depicts a system (e.g., an AR display system) 900 for presenting images to the user's eye 902 and for viewing the world 904 according to some embodiments. The system 900 includes a segmented illumination / dimming light source 910, a spatial light modulator (SLM) 940, and a waveguide 920 arranged such that light from the light source 910 illuminates the SLM 940, and light reflected from the SLM 940 is coupled into the waveguide 920 to be directed to the eye 902. The system 900 includes optics 930 disposed to both illuminate at least a portion of the SLM 940 and project an image of the SLM 940. Light from the segmented illumination / dimming light source 910, for example, propagates in a first direction through the optics 930 onto at least a portion of the SLM 940 thereby illuminating at least a portion of the SLM 940. Light reflected from the SLM 940 propagates again through the optics 930 in a second direction opposite the first direction and is directed to the waveguide 920 and coupled therein.

[0097] The segmented illumination / dimming light source 910 may include an array of independently addressable / operable LEDs or other types of light sources in an array of independently addressable / operable array. In some embodiments, such as the one depicted in Figure 9, the segmented illumination / dimming light source 910 is a 10 x 10 array of LEDs. In other embodiments, the segmented illumination / dimming light source 910 can be other arrays having other numbers of LEDs in each direction (e.g., any numbergreater than 0). While the depicted segmented illumination / dimming light source 910 is a square shaped array, other shapes are also In various embodiments, subgroups of the LEDs in the array forming the segmented illumination / dimming light source 910 are independently addressable / operable. The LEDs may be operable in on / off states or operable at various brightness levels from 0% (off) to 100%. The LEDs may be configured to emit light of one color. While the system 900 depicted in Figure 9 includes a single segmented illumination / dimming light source 910, systems according to other embodiments include multiple segmented illumination / dimming light sources. In some embodiments, the system includes three segmented illumination / dimming light sources, one for each of three colors (e.g., red, green, and blue; purple, cyan, and yellow; or any other colors). In some embodiments, the system includes two segmented illumination / dimming light sources, one for a first color or combination of colors (e.g., red) and one for a second color or combination of colors (e.g., green and blue).

[0098] In some embodiments, the multiple segmented illumination / dimming light sources are executed on a single panel with separate or partially overlapping portions of the single panel functioning as each segmented illumination I dimming light source. In some embodiments, the multiple segmented illumination / dimming light sources are executed on a plurality (e.g., two or three) of panels. Figure 18 depicts a segmented illumination / dimming light source 1810 executed on three panels according to some embodiments. The segmented illumination / dimming light source 1810 includes a red panel 1812, a green panel 1814, and a blue panel 1816. Figure 19 depicts a segmented illumination I dimming light source 1910 executed on three panels according to some embodiments. The segmented illumination / dimming light source 1910 includes a firstred / green / blue (“RGB”) panel 1912, a second RGB panel 1914, and a third RGB panel 1916. Figure 20 depicts a segmented illumination / dimming light source 2010 executed on three panels according to some embodiments. The segmented illumination I dimming light source 2010 includes a first yellow / magenta / cyan (“YMC”) panel 2012, a second YMC panel 2014, and a third YMC panel 2016. While the RBG and YMC segmented illumination / dimming light sources 1810, 1910, 2010 each have three exemplary colors, other embodiments of segmented illumination I dimming light sources may have more than three colors. In other embodiments, the colors of the segmented illumination / dimming light sources may be different from RGB and YMC.

[0099] The segmented illumination / dimming light source 910 may be a polarized light source, however the segmented illumination I dimming light source 910 need not be so limited. In some implementations, a polarizer 915 may be positioned between the segmented illumination / dimming light source 910 and the SLM 940. As illustrated, the polarizer 915 is between the segmented illumination / dimming light source 910 and the waveguide 920. This polarizer 915 may also be a light recycler, transmitting light of a first polarization and reflecting light of a second polarization back to the segmented illumination / dimming light source 910. Such a polarizer 915 may be, for example, a wire grid polarizer. A coupling optic 905, such as a non-imaging optical element (e.g., cone, compound parabolic collector (CPC) or lenses, may be disposed with respect to the segmented illumination / dimming light source 910 to receive light output from the segmented illumination I dimming light source 910. The coupling optic 905 may collect the light from the segmented illumination I dimming light source 910 and may, in some cases, reduce the divergence of light emitted from the segmented illumination / dimminglight source 910. The coupling optic 905 may, for example, collimate the light output from the segmented illumination / dimming light source 910. The coupling optic 905 may collect light that matches the angular spectrum field of view of the system 900. Accordingly, the coupling optic 905 may match an angular spectrum of the light output by the segmented illumination I dimming light source 910 with the field of view of the system 900. The coupling optic 905 may have an asymmetric profile to operate on the light emitted from the segmented illumination I dimming light source 910 asymmetrically. For example, the coupling optic 905 may reduce the divergence a different amount in orthogonal directions (e.g., x and z directions). Such asymmetry in the coupling optic 905 may address asymmetry in the light emitted from the segmented illumination I dimming light source 910 which may include, for example, LEDs that emit a wider range of angles of light in one direction (e.g., x or z) as opposed to the orthogonal direction (e.g., z or x, respectively).

[0100] As discussed above, the system 900 includes optics 930 configured to illuminate the SLM 940 that is disposed in an optical path between the segmented illumination I dimming light source 910 and the SLM 940. The optics 930 may include transmissive optics that transmits light from the segmented illumination I dimming light source 910 to the SLM 940. The optics 930 may also be configured to project an image of the SLM 940 or formed by the SLM 940 into the waveguide 920. An image may be projected into the eye of the eye 902. In some designs, the optics 930 may include one or more lenses or optical elements having optic power. The optic 930 may, for example, have positive optical power. The optics 930 may include one or more refractive opticalelements such as refractive lenses. Other types of optical elements may also possibly be used.

[0101] The SLM 940 may be reflective, modulating and reflecting light therefrom. The SLM 940 may be a polarization based SLM configured to modulate polarization. The SLM 940 may, for example, include a liquid crystal (LC) SLM (e.g., a liquid crystal on silicon (LCOS) SLM). The LCOS SLM may, for example, include twisted nematic (TN) liquid crystal. The SLM 940 may, for example, include one or more pixels that are configured to selectively modulate light incident on the pixel depending on the state of the pixel. For some types of SLMs 940, the pixel may, for example, modulate the beam incident thereon by altering the polarization state such as rotating the polarization (e.g., rotating the orientation of linearly polarized light).

[0102] As discussed above, the SLM 940 may be a LCOS SLM 940. In a crosspolarizer configuration, the LCOS SLM 940 may be nominally white. When a pixel is off (e.g., 0 voltage), it has a bright state, and when the pixel is on (e.g., voltage above a threshold turn on voltage), it has a dark state. In this cross-polarization configuration, leakage is minimized when a pixel is on and it has a dark state.

[0103] In a parallel-polarizer configuration, the LCOS SLM 940 is nominally black. When a pixel is off (e.g., 0 voltage), it has a dark state, and when the pixel is on (e.g., voltage above a threshold turn on voltage), it has a bright state. In this parallel-polarizer configuration, leakage is minimized when a pixel is off and it has a dark state. The dark state may be (re)optimized using rub direction and compensator angle. Compensator angle may refer to an angle of a compensator (not shown) which may be between the optics 930 and the SLM 940.

[0104] Dynamic range and throughput for parallel-polarizer configurations may be different than that of cross-polarizer configurations. Further, parallel-polarizer configurations may be optimized for contrast differently than cross-polarizer configurations.

[0105] The system 900 includes the waveguide 920 for outputting image information to the eye 902. The waveguide 920 may include substantially transparent material having a refractive index sufficient to guide light therein . As illustrated, the waveguide 920 may include a first side 921 and a second side 923 opposite the first side 921 and corresponding upper and lower major surfaces as well as edges there around. The first and second major 921 , 923 surface may be sufficiently flat such that image information may be retained upon propagating light from the SLM 940 to the eye 902 such than an image formed by the SLM 940 may be injected into the eye 902. The optics 930 and the SLM 940 may be positioned on the first side 921 of the waveguide 920. The segmented illumination / dimming light source 910 may be disposed on the second side 923 such that light from the segmented illumination / dimming light source 910 is incident on the second side 923 prior to passing through the waveguide 920 and through the optics 930 to the SLM 940. Accordingly, the waveguide 920 may be disposed between the segmented illumination I dimming light source 910 and the optics 930. Additionally, at least a portion of the waveguide 920 may extend between the segmented illumination / dimming light source 910 and the optics 930, whereby light passes through the portion of the waveguide 920 to the optics 930. Light emitted from the segmented illumination / dimming light source 910 can therefore be directed through the waveguide 920, into andthrough the optics 930 and incident on the SLM 940. The SLM 940 reflects the light back through the optics 930 and to the waveguide 920.

[0106] The system 900 also includes an in-coupling optical element 960 for coupling light from the optics 930 into the waveguide 920. The in-coupling optical element 960 may be disposed on a major surface (e.g., an upper major surface 923) of the waveguide 920. In some designs, the in-coupling optical element 960 may be disposed on the lower major surface 921 of the waveguide 920. In some designs, the in-coupling optical element 960 may be disposed in the body of the waveguide 920. While illustrated on one side or corner of the waveguide 920, the in-coupling optical element 960 may be disposed in / on other areas of the waveguide 920. The in-coupling optical element 960 may be a diffractive optical element or a reflector. Other structures may be used as the in-coupling optical element 960. The in-coupling optical element 960 may be configured to direct the light incident thereon into the waveguide 920 at a sufficiently large grazing angle (e.g., greater than the critical angle) with respect to the upper and lower major surfaces 923, 921 of the waveguide 920 to be guided therein by total internal reflection. Further, the incoupling optical element 960 may operate on a wide range of wavelengths and thus be configured to couple light of multiple colors into the waveguide 920. For instance, the incoupling optical element 960 may be configured to couple red light, green light, and blue light into the waveguide 920. The segmented illumination I dimming light source 910 may emit red, green, and blue color light at different times.

[0107] The system 900 includes a light distributing element 970 disposed on or in the waveguide 920. In some embodiments, the light distributing element 970 may be an orthogonal pupil expander (OPE). The light distributing element 970 may be configuredto spread the light within the waveguide 920 by turning the light propagating in an x direction, for example, toward a z direction. The light distributing element 970 may, thus, be configured to increase dimensions of the eyebox along the z-axis. The light distributing element 970 may, for example, include one or more diffractive optical elements configured to diffract the light propagating within the waveguide 920 incident the diffractive optical elements so as to redirect that light, for example, in a generally orthogonal direction. Other configurations are possible.

[0108] For instance, embodiments with multiple segmented illumination / dimming light sources may have multiple waveguides corresponding to each of the segmented illumination I dimming light sources. In such embodiments, each of the multiple waveguides may have in-coupling gratings that do not overlap with the in-coupling gratings for the other waveguides in order to minimize unintended in-coupling into the other waveguides. Figures 10A-10D depict a prior art display system 1000 for presenting images to a user’s eye and for viewing the world according to some embodiments. The display system 1000, similar to the display system 80 described above, includes a wearable frame structure 1060. The frame structure 1060 may be in the form of an eyeglasses shape (binocular or monocular) having an eye rim 1062 which surrounds and holds the eyepiece 1066. A pair of temples (for binocular eyeglasses) (not shown in Figures 10A-10D) extend from the temple portion 1064 (see Figure 10C) of the eye rim 1062 (similar to the temples 84 in Figure 2). The temples are configured to rest on the user’s ears to support the display system 1000 while worn on the user’s head. A mounting boss 1036 for housing a lens barrel housing 1034 is positioned near the temple portion 1064 of the eye rim 1062 such that the center axis of the mounting boss 1036 issubstantially perpendicular to the plane of the eyeglass lens 1066. The frame structure 1060 may be formed of any suitable metal, such as aluminum, magnesium, titanium, an alloy of magnesium, aluminum or titanium, a metal matrix composite (“MMC”), or other suitable metal. In other embodiments, the frame structure 1060 may be formed of plastic or polymeric material, including thermoplastic polymers, thermoset polymers, etc. In the case of a frame structure 1060 formed of plastic or polymeric material, the components of the frame structure 1060, such as the bosses 1036, described as being metallic may also be formed of a plastic or polymer.

[0109] The display system 1000 includes a display assembly 1002 installed in the frame structure 1060. The display assembly 1002 includes an illuminator 1050, a viewing optics / lens assembly 1015 including a waveguide 1020 (which may comprise a stack of a plurality of waveguides (e.g., three) or a single waveguide) , an SLM 1040, and optics 1030 (e.g., a lens stack 1030), disposed to both illuminate at least a portion of the SLM 1040 and project an image of the SLM 1040 to the user’s eye.

[0110] The lens stack 1030 includes a plurality of plastic lenses 1032a, 1032b and 1032d and a glass lens 1032c. The lens stack 1030 in the illustrated example of Figure 10 includes four lenses 1032a-1032d, but the lens stack 1030 may include any suitable number of lenses. The lens stack 1030 is housed in a lens barrel housing 1034. The lens barrel housing 1034 is also formed of plastic, like the lenses 1032 of the lens stack 1030, such that the lenses 1032 and the lens barrel housing 1034 have similar coefficients of thermal expansion (CTE). Without the plastic lens barrel housing 1034, the plastic lenses 1032 expand and contract much faster than the metal mounting boss 1036 of the metal frame structure 1060, which would cause lens clearance problems (decentering / tilt) atlow temperatures (e.g., while shipping and / or in storage) and birefringent at high temperatures. Plastic lenses are also hydrophilic such that they absorb water over time which changes the shape of the lens thereby changing the optical properties of the plastic lens. These issues cause reduced optical performance of the display assembly 1002. Plastic lenses are very birefringent which means that stresses on the plastic lenses 1032, either thermal or mechanical, caused by thermal expansion or mechanical loads, will cause a change in the optical properties (e.g., change the refraction of light) of the plastic lenses 1032 which degrades the optical performance of the lens as measured by optical key performance indexes (KPIs) of the display system 1000.

[0111] The illuminator 1050 includes a light source 1010 and coupling optics 1005 for distributing light generated by the light source 1010 onto the SLM 1040. In one embodiment, the light source 1010 comprises three LEDs 1011 (only two of the three LEDs 1011 a, 1011b are shown in Figure 10 (e.g., one LED 1011 for each of red, green, and blue colors) which forma Lambertian light source. The coupling optics 1205 may include a coupling optic 1206 for each LED, such as a non-imaging optical element (e.g., cone, CPC, lenses), disposed with respect to the light source 1010 to receive light output from the light source 1010. In the illustrated embodiment, the coupling optics 1005 (e.g., one or more CPCs) includes a coupling optic 1006a, 1006b (e.g., a CPC) for each respective LED 1011 a, 1011 b (only two of the three coupling optics 1006 are shown in Figure 10A). Each coupling optic 1006 appropriately adapts the angular distribution of light generated by each respective LED 1011 onto the SLM 1040, creates the appropriate treid angte tor the dsspiay system and directs the rght toward the barre aperture. An electrical cable 1052, such as a flex cable, has a first end connected to the displayassembly 1002. In the illustrated embodiment of Figures 10A-10D, the first end of the electrical cable 1052 connects to the display assembly 1002 via the illuminator 1050. The second end of the electrical cable 1052 is configured to be in electrical communication with the local processing and data module 70 (see Figure 2).

[0112] The structure and function of the various optical components of the display system 1000 depicted in Figures 10A-10D are similar to those of the corresponding optical components of the system 900 depicted in Figure 9 and described above.

[0113]

[0114] Figures 10A and 10B show the exterior of the display system 1000 to better show the frame structure 1060 (same or similar to frame structure 64, as shown in Figure 2). In the exemplary embodiment of Figures 10B and 10D, the frame structure 1060 may be in the form of an eyeglasses shape (binocular or monocular) having an eye rim 1062 which surrounds and holds the eyepiece 1066. A pair of temples (for binocular eyeglasses) (not shown) may extend from the temple portion 1064 of the eye rim 1062. The mounting boss 1036 is positioned near the temple portion 1064 of the eye rim 1062 such that the center axis of the mounting boss 1036 is substantially perpendicular to the plane of the eyepiece 1066.

[0115] As shown in Figure 11 , the light source may comprise one or more LED arrays forming a Lambertian light source. The display system (e.g., an XR display system) 1100 for presenting images to a user’s eye and for viewing the world includes a segmented illumination / dimming light source 1110, a waveguide 1120, an SLM 1140, and optics 1130 disposed to both illuminate at least a portion of the SLM 1140 and project an image generated using the SLM 1140, through the waveguide 1120, and to the user’s eye. Thesystem 1100 also includes a coupling optic 1105. The structure and function of the various optical components of the system 1100 depicted in Figure 11 are similar to those of the corresponding optical components of the system 900 depicted in Figure 9 and described above.

[0116] The segmented illumination I dimming light source 1110 includes an array of independently addressable / operable LEDs. By controlling the voltage / current applied to each LED / sub-light source, the amount of light delivered to corresponding portions 1142 of the SLM 1140 and the waveguide 1120 can be controlled. The amount of light delivered to various portions 1142 of the SLM 1140 and onto the waveguide 1120 can be controlled to minimize / eliminate nonuniformities, distortions, artifacts, and / or aberrations in the image displayed to the user.

[0117] Turning to Figures 12A-12J, in one embodiment disclosed herein, an improved display system 1200 is illustrated. In the display system 1200, the lens stack 1230 is loaded directly into a projection lens barrel 1236 formed integrally with the metal frame structure 1260, eliminating the need for the separate lens barrel housing 1034 used with the display system 1000. As used herein, the term “integral” and “integrally” mean that an element is formed monolithically with another element, and that the elements are not separate parts connected to each other by an attachment means such as bonding, welding, fasteners, etc. The lens stack 1230 in the display system 1200 includes glass lenses 1232 instead of the plastic lenses 1032 used in the display system 1000. As depicted in the side-by-side comparisons of Figures 10B and 12B and Figures 10C and 12C, it can be seen that the integrally formed projection lens barrel 1236 and glass lens stack 1230 used in the design of the display system 1200 allows miniaturization of theprojection lens barrel and lens stack assembly as compared to the display system 1000, thereby providing a more compact overall display system. The display system 1200 can enable a reduction in volume of the projection lens barrel 1236 and lens stack assembly 1230 from 50% to 80% compared to the display system 1000.

[0118] The display system 1200, similar to the display systems 80 and 1000 described above, includes a wearable frame structure 1260. The frame structure 1260 may be in the form of an eyeglasses shape (binocular or monocular) having an eye rim 1262 which surrounds and holds the eyepiece 1266. The eyepiece 1266 may comprise a waveguide 1220 covered by protective cover glass (also referred to as a waveguide assembly 1222), or it may be solely comprise waveguide elements 1220 such that the eyepiece 1266 is a fully active element. Figures 12E-12G illustrate various assemblies and components of the display system 1200 in a binocular display system 1200a, while Figures 12C and 121- 12J illustrate various assemblies and components of the display system 1200 in a binocular display system 1200b. Figures 12D and 12H show the display system 1200 in both a binocular display system 1200a and a monocular display system 1200b. Figures 12A and 12B show the display assemblies 1202 which are applicable to both the binocular display system 1200a and a monocular display system 1200b . The binocular display system 1200a includes a separate viewing optics assembly 1202 for each of the user’s left eye right eye, whereas the monocular display system 1200b includes a viewing optics assembly 1202 for just one of the user’s eyes. In the illustrated embodiments, the monocular display system 1200b is designed for the user’s left eye, with the understanding that the monocular display system 1200b can be configured for the user’s right eye by simply mirroring the assembly. The binocular display system 1200a and themonocular display system 1200b are the same, except that the binocular display system 1200a is basically two monocular display systems 1200b connected together such that each monocular display system 1200b provides images to a respective left eye and right eye of the user. Accordingly, the description of the same or similar components of the binocular display system 1200a apply to the monocular display system 1200b, where applicable, and vice versa.

[0119] The binocular display system 1200a includes a pair of temples (not shown in Figures 12A-12J) which extend from the respective left and right temple portions 1264a, 1264b (see Figure 10C) of the respective eye rims 1262a, 1262b (similar to the temples 84 in Figure 2). Alternatively, the binocular display system 1200a may have an alternative attachment device (not shown) such as one or more straps, bands, and / or other securement devices, or assembly into a wearable device such as a helmet or headset. The monocular display system 1200b may be worn using a suitable attachment device (not shown) such as one or more straps, bands, and / or other securement devices, or assembly into a wearable device such as a helmet or headset. As shown in Figures 12

[0120] Referring to the binocular display system 1200a, the frame structure 1260 includes 1260 includes a left eye rim 1262a and a right eye rim 1262b which each surround and hold a respective eyeglass lens 1266a, 1266b. The frame structure 1260 also includes an integrally formed left projection lens barrel 1236a positioned near the left temple portion 1264a and an integrally formed right projection lens barrel 1236b position near the right temple portion 1264b. The projection lens barrels 1236a, 1236b are a substantially perpendicular to the plane of the respective eyeglass lenses 1266a, 1266b. The frame structure 1260 may be formed of any suitable metal, such as aluminum,magnesium, titanium, an alloy of magnesium, aluminum or titanium, a metal matrix composite (“MMC”), or other suitable metal. Alternatively, the frame structure 1260 may be formed of a polymer material, such as any suitable plastic.

[0121] The binocular display system 1200a includes a left display assembly 1202 a and a right display assembly 1202b installed in the respective left and right temple portions 1264a, 1264b. The left display assembly 1202a and the right display assembly 1202b are identical, and therefore, the description of a display assembly 1202 applies to both the left and right display assemblies 1202a, 1202b. As best shown in Figure 12A, each display assembly 1202 includes an illuminator 1250, a viewing optics / lens assembly 1215 including a waveguide stack 1220 (e.g., a stack of a plurality of waveguides (e.g., three waveguides, or two waveguides), or a single plane waveguide configured to transmit all 3 colors), an SLM 1240, and optics 1230 (e.g., lens stack 1230) disposed to both illuminate at least a portion of the SLM 1240 and project an image from the SLM 1240 to the user’s eye.

[0122] The lens stack 1230 includes a plurality of glass lenses 1232a-1232d. The lens stack 1230 in the illustrated example of Figure 12A includes four lenses 1232a-1232d, but the lens stack 1230 may include any suitable number of lenses. The 1232 of the lens stack 1230 are made of glass. The glass lenses 1232 do not require the extra margin around the lens molding the plastic lenses 1032 used in the display system 1000, and therefore, the glass lenses 1232 can be manufactured much smaller in diameter than the plastic lenses 1032 for a given lens specification. Glass lenses, such as the glass lenses 1232, also have the advantage of not being birefringent like the plastic lenses 1032 of the display system 1000. Glass lenses are also not hydrophilic, and do not absorb water.Thus, the glass lenses 1232 exhibit stable optical properties when subjected to humidity thermal and mechanical stresses caused by thermal expansion or mechanical loads and when in the presence of water (e.g., humidity) over time.

[0123] As shown in Figures 12A and 12G, the lens stack 1230 inserts directly into the integral lens projection barrel 1236. There may be a respective spacer 1238 between each lenses 1232 and the adjacent lens(es) 1232. The glass lenses 1232 have a CTE that more closely matches the CTE of the metal projection barrel 1236, such that the glass lenses 1232 expand and contract at a more similar rate to the metal lens projection barrel 1236 than plastic lenses 1032. Thus, the combination of glass lenses 1232 housed in the metal lens projection barrel 1236 does not cause lens clearance problems (decentering / tilt) at low temperatures (e.g., while shipping and / or in storage) or birefringence at high temperatures. In other words, the optical performance of the display assembly 1202 is maintained over an expected operating temperature range such as from 5° C - 45° C. Accordingly, the optical performance of the display assembly 1202 comprising the lens stack 1230 as measured by KPIs is not affected by temperature changes, thermal or mechanical stresses or contact with water (e.g., humidity).

[0124] The display assembly 1202 may also include a polarizer 1268 disposed on the world side of the lens stack 1030 (see Figure 12G), such as attached to the world side of the eye rim 1262 and positioned in front of the lens stack 1030. The polarizer 1268 may be any suitable polarizer, such as a frequency selective polarizer (FSP).

[0125] The display assembly 1202 also includes a coupling optic 1205 for each LED, such as a non-imaging optical element (e.g., cone, CPC, lenses), disposed with respect to the light source 1210 to receive light output from the light source 110. The structureand function of the various optical components of the display system 1000 depicted in Figure 10 are similar to those of the corresponding optical components of the system 900 depicted in Figure 9 and described above.

[0126] The illuminator 1250 includes a light source 1010 and coupling optics 1005 for distributing light generated by the light source 1210 onto the SLM 1240. The illuminator 1250 is mounted on the world side of the eyeglass lens 1266, waveguide 1220 and the eye rim 1262. Instead of bonding the illuminator to the frame structure as in the display system 1000, the illuminator 1250 is bonded directly to the eyeglass lens 1226 / waveguide 1220 assembly (also referred to as the eyepiece or EP). The light source 1210 may comprise three LEDs 1011 (only one of the three LEDs 1211 a is shown in Figure 12A (e.g., one LED 1211 for each of red, green, and blue colors) which form a Lambertian light source. The coupling optics 1205 may include a coupling optic 1206 for each LED, such as a non-imaging optical element (e.g., cone, CPC, lenses), disposed with respect to the light source 1210 to receive light output from the light source 1210. In the illustrated embodiment, the coupling optics 1005 (e.g., one or more CPCs) includes a coupling optic 1206a (e.g., a CPC) for each respective LED 1211 a (only one of the three coupling optics 1206 is shown in Figure 10A). Each coupling optic 1206 appropriately adapts the angular distribution of light generated by each respective LED 1211 onto the SLM 1240. An electrical cable 1252, such as a flex cable or flex circuits, has a first end connected to the display assembly 1202. In the illustrated embodiment of Figures 12A- 12J, the first end of the electrical cable 1252 connects to the display assembly 1202 via the illuminator 1250. The second end of the electrical cable 1252 is configured to be in electrical communication with the local processing and data module 70 (see Figure 2).

[0127] The structure and function of the various optical components of the display system 1200 depicted in Figures 12A-12J are similar to those of the corresponding optical components of the system 900 depicted in Figure 9 and described above.

[0128] Accordingly, the display system 1200 has many technical advantages over the display system 1000. The innovative integral projection lens barrel 1236 and glass lenses loaded directly into the projection lens barrel 1236 enable a significant size reduction in the display assembly 1202 as compared to the display assembly 1002. As a specific example, as shown in the side-by-side comparison of Figures 10B and 12B, the display assembly 1202 has a length L1 of 12.8mm and a diameter D1 of 8.5 mm, as compared to the display assembly 1002 which has a length L2 of 15.9 mm and a diameter of 17.2 mm. Approximating the display assemblies 1202 and 1002 as cylinders, the display assembly 1202 has a volume of about 726 mm3and the display assembly 1002 has a volume of about 3694 mm3. This represents about an 80% reduction in volume of the display assembly 1202 as compared to the display assembly 1002. Furthermore, as explained herein, the glass lenses 1232 provide the display assembly 1202 with a much more stable and higher display performance as measured by optical KPIs than the display assembly 1002 having plastic lenses 1032.

[0129] Turning now to Figures 13-17, features, aspects, and methods of manufacture for the display systems 1000 and 1200 will now be described. These features, aspects, and methods of manufacture improve the precision, accuracy, and manufacturability of the display system 1200. For example, the accuracy of the relative position between the waveguide 1020, 1320 and the lens stack 1030, 1230 of the respective display assemblies 1002, 1202 is critical for the performance of the display systems 1002, 1202.This relative position includes both the relative Z-position along the optical axis 1080, 1280, and the pitch and yaw angle between the waveguide 1020, 1320 and the lens stack 1030, 1230. Accordingly, it is beneficial to improve the manufacturing positioning tolerances between the lens stack 1030, 1230 and the waveguide 1020, 1220 along the optical axis 1080, 1280 when assembling the lens stack 1030, 1230 and waveguide 1020, 1220 to the frame 1060, 1260. Several embodiments from improving the positioning tolerances between the lens stack 1030, 1230 and the waveguide 1020, 1220 along the optical axis 1080, 1280 when assembling the lens stack 1030, 1230 and waveguide 1020, 1220 to the frame 1060, 1260 will now be described with reference to Figures 13-16.

[0130] Figures 13A-13B show a first scheme for improving the positioning tolerances between the lens stack 1030, 1230 and the waveguide 1020, 1220 when assembling the lens stack 1030, 1230 and waveguide 1020, 1220. This scheme is applicable to the display assemblies 1002 and 1202 for both the display system 1000 and the display system 1202. The frame structure 1060, 1260 has a plurality of frame datums 1302 circumferentially spaced apart around the inside perimeter of each eye rim 1062, 1262 upon which the waveguide 1020, 1220 will rest when the waveguide 1020, 1220 are assembled into the eye rims 1062, 1262. The frame datums 1302 may comprise pucks or other suitable bosses extending interiorly from the inside perimeter of each eye rim 1062, 1262. In this embodiment, there are two frame datums 1302 on each eye rim 1062, 1262, i.e. , two frame datums 1302a, 1302b on the left eye rim 1062, 1262a and two frame datums 1302c, 1302c on the right eye rim 1062, 1262b. The frame datums 1302 may be precision molded, machined or bonded (e.g., glued, welded, soldered, etc.) in place onto the eye rims 1062, 1262. The frame datums 1302 may be metal (e.g., when molded ormachined into the eye rims 1062, 1262), or plastic / polymer (e.g., when bonded onto the eye rims 1062, 1262).

[0131] A lens stack datum 1304a, 1304b is disposed on the front side of each lens stack 1030, 1230. In the case of the use of the lens barrel housing 1034 for the display assembly 1002, the lens stack datums 1304a, 1304b may be disposed on the front side of the lens barrel housing 1034. Again, the lens stack datums 1304 may be molded, machined or bonded (e.g., glued, welded, soldered, etc.) in place onto the lens stack 1030, 1230 or lens barrel housing 1034.

[0132] Referring now to Figure 13B, the precision assembly of the method for the lens stack 1030, 1230 and waveguide 1020, 1220 to the frame 1060, 1260 using the datums 1302, 1304 will now be described. An assembly tool 1306 is provided. The assembly tool 1306 is a precision jig having tool base 1307 and a jig frame datum 1308 and a jig lens stack datum 1310 mounted on the tool base 1307.

[0133] In the illustrated embodiment of Figure 13B, the jig frame datum is a raised platform in the precise shape of the eye rims 1062, 1262 to receive the eye rim 1062, 1262. The jig frame datum 1308 has a top surface 1312 configured such that the frame datums 1302 rest on the top surface 1312 when the frame structure 1060, 1260 is installed on the assembly tool 1306. The jig lens stack datum 1310 is another platform extending upward from the top surface 1312 of the jig frame datum 1308, and has a top surface 1314 configured such that the lens stack datum 1304 rests on the top surface 1314 when the frame structure 1060, 1260 is installed on the assembly tool 1306. The jig frame datum 1308 and lens stack datum 1302 are arranged on the assembly tool 1306 such that the distance between the top surface 1312 and top surface 1314 will positionthe lens stack 1030, 1230 relative to the waveguide 1020, 1220 along the optical axis 1080, 1280, and the pitch and yaw angle of the lens stack 1030, 1230 relative to the waveguide 1020, 1220, within a tight tolerance of the nominal desired design specification.

[0134] In alternative embodiments, the jig lens stack datum 1310 and jig frame datum 1308 may comprise one or more datum pins (not shown), posts, or the like which extend from the tool base 1307 and similarly interface with the frame datums 1302 and the lens stack datum 1304.

[0135] In the illustrated embodiment, the assembly tool 1306 only has the jigs for assembling the left side of the display assembly 1002, 1202, but it is to be understood that the assembly tool 1306 may have another jig frame datum 1308 and jig lens stack datum 1302 in mirrored image of the left side (not shown in Figure 13B) for receiving and assembling the right side of the display assembly 1002, 1202, or alternatively, a separate assembly tool similar to the assembly tool 1306 may be provided for assembling the right side of the display assembly 1002, 1202. Of course, the assembly tool 1306 may also be used to assemble the monocular versions of the display systems 1000, 1200.

[0136] Accordingly, to assemble the lens stack 1030, 1230 and waveguide 1020, 1220 to the frame 1060, 1260, the frame 1060, 1260 is first installed onto the assembly tool 1306 such that the frame datums 1302 rest on the jig frame datum 1308. The lens stack 1030, 1230, or lens barrel housing 1034 having the lens stack 1030 installed therein, is inserted into mounting boss 1036 (for display system 1000) or projection lens barrel 1236 (for display system 1200) until the lens stack datum 1304 rests on the jig lens stack datum1310. The lens stack 1030, 1230, or lens barrel housing 1034 is now accurately positioned in the frame 1060, 1260, and is bonded in place using a suitable adhesive.

[0137] The frame 1060, 1260 is then removed from the assembly tool 1306 for installation of the waveguide 1020, 1220. The waveguide 1020, 1220 is then positioned in the eye rims 1062, 1262, such that the waveguide 1020, 1220 rests on the frame datums 1302 and the lens stack datum 1304. As shown in Figure 13A, for the right eye rim 1062, 1262a, the two frame datums 1302a, 1302b and the single lens stack datum 1304a define a plane at a precise position along the optical axis 1080, 1280 relative to the lens stack 1030, 1230 (the same is true for the left eye rim 1062, 1262b). The waveguide 1020, 1220 may then be tacked in place in the eye rims 1062, 1262 using a tacking adhesive. Then, a perimeter bond is applied to firmly bond the waveguide 1020, 1220 into the eye rims 1062, 1262.

[0138] As described herein, the waveguide 1020, 1220 may comprise the entire eyepiece 1066, 1266 bonded into the eye rims 1062, 1262, or the waveguide 1020, 1220 may be enclosed within a protective cover glass to form the waveguide assembly 1022, 1222. In the case that a cover glass encloses the waveguide 1020, 1220, the cover glass enclosing the waveguide 1020, 1220 contacts the various datums where it is described that the waveguide 1020, 1220 contact the datums.

[0139] Figures 14A-14D illustrate a second scheme for improving the positioning tolerances between the lens stack 1230 and the waveguide 1220 when assembling the lens stack 1230 and waveguide 1220 to the frame 1260. This second scheme will be described with respect to the display system 1200 with the understanding that it is equally applicable to the display system 1000. The second scheme is similar to the first schemedescribed above except that all three of the positioning datums for each waveguide 1220 are located on the eye rim 1262 and the position of the lens stack 1230 and / or lens stack assembly 1235 along the optical axis 1280 is set by a lens datum 1404 precision machined or molded into the frame 1260 instead of a lens datum on the lens stack 1230 or lens stack assembly 1235 (described below).

[0140] The frame structure 1260 has a plurality of frame datums 1402 circumferentially spaced apart around the inside perimeter of each eye rim 1262 upon which the waveguide 1220 will rest when the waveguide 1220 is assembled into the eye rims 1262. The frame datums 1402 are precision machined or molded bosses extending interiorly from the inside perimeter of each eye rim 1262. In the illustrated embodiment of Figures 14A-14C, each eye rim 1262 has three frame datums 1302, i.e., the left eye rim 1262a has three frame datums 1302a, 1302b, 1302c spaced apart by about 60° circumferentially around the left eye rim 1262a and the right eye rim 1262b has three frame datums 1302d, 1302e, 1302f spaced apart by about 60° circumferentially around the right eye rim 1262b. The frame datums 1302 may be precision molded, machined or bonded (e.g., glued, welded, soldered, etc.) in place onto the eye rims 1062, 1262. The frame datums 1302 may be metal (e.g., when molded or machined into the eye rims 1062, 1262), or plastic / polymer (e.g., when bonded onto the eye rims 1062, 1262).

[0141] The lens datum 1404 may comprise one or more precision machined or molded bosses positioned at the front of the projection lens barrel 1236. The lens datum 1404 is configured to precisely position the lens stack 1230 or a lens stack assembly 1235 (see Figure 16B) comprising a lens stack barrel 1234 having the lens stack 1230 installed therein. The lens datum 1404 is configured to allow the front surface of the lens stack1230 or front surface of the lens stack assembly 1235 installed therein to rest against the lens datum 1404 thereby precisely positioning the lens stack 1230 along the optical axis 1280.

[0142] The assembly of the waveguide 1220 and lens stack 1230 onto the frame 1260 using this second scheme is straightforward. The lens stack 1230 or lens stack assembly 1235 is inserted into the projection lens barrel 1236 of the frame 1260 until the front surface of the lens stack 1230 or front surface of the lens stack assembly 1235 bears against the lens datum 1404. The lens stack 1230 or lens stack assembly 1235 is then bonded in place within the projection lens barrel 1236. The waveguide 1220 (or waveguide assembly 1222, as described herein) is then inserted into the eye rim 1262 with the user side of the waveguide 1220 bearing against all three of the respective frame datums 1302. As best shown in Figure 14C, the waveguide 1220 is then tacked in place to the eye rim 1262 using a tacking adhesive to form a plurality of circumferentially spaced tacking bonds 1406. For example, 3, 4, 5 or more tacking bonds 1406 may be utilized. Next, the waveguide 1220 is bonded and sealed into the eye rim 1262 using a perimeter seal 1408 which may be applied in a plurality of segments between the tacking bonds 1406. The illuminator 1250 is then installed over the lens stack 1230 on the front side of the frame 1260. The illuminator 1250 may be bonded to the eye rim 1262 of the frame 1260 or directly to the front side of the waveguide 1220 (as described in more detail herein). In the case of a binocular display system 1200, this assembly process is performed for both the left side and right side of the display assembly 1202.

[0143] Referring to Figures 15A-15D, a third scheme for improving the positioning tolerances between the lens stack 1230 and the waveguide 1220 when assembling thelens stack 1230 and waveguide 1220 into the frame 1260 is illustrated. This third scheme will also be described with respect to the display system 1200 with the understanding that it is equally applicable to the display system 1000. This third scheme is substantially the same as the second scheme described above, except that third scheme utilizes precisely positioned frame datums 1502 bonded onto the eye rim 1262. The third scheme uses the same molded lens datum 1404 for precisely positioning the lens stack 1230 and / or lens stack assembly 1235.

[0144] The frame 1260 is formed with a plurality of frame datum holders 1502 positioned on the eye rims 1262a, 1262b in the same or similar positions as the frame datums 1402 for the second scheme described above. The frame datum holders 1502 are bosses molded or machined into the frame 1260 and are configured to adjustably receive and retain in place a respective frame datum 1502. The frame 1260 is installed on an assembly tool (not shown) having a plurality of jigs, pins and or posts to precisely position the frame 1260 on the assembly tool. The assembly tool also has a plurality of frame datum positioning posts located at the position of each frame datum holder 1502. Each frame datum positioning post has a positioning surface precisely positioned at the proper height along the optical axis 1280 of a respective frame datum 1502 relative to the installed frame 1260. A respective frame datum 1502 is then installed in each frame datum holder 1502 such that the respective frame datum 1502 bears against the respective positioning surface of the respective frame datum positioning post. Each frame datum 1502 is bonded in place using an adhesive bond 1504 at the position set by the assembly tool. In the illustrated embodiment, each frame datum 1502 comprises a puck,such as a plastic / polymer puck or other suitable device for setting the position of the waveguide 1220.

[0145] The assembly of the waveguide 1220 (or waveguide assembly 1222) and lens stack 1230 onto the frame 1260 according to this third scheme is the same as for the second scheme described above.

[0146] Referring to Figures 16A-16D, a fourth scheme for improving the positioning tolerances between the lens stack 1230 and the waveguide 1220 when assembling the lens stack 1230 and waveguide 1220 into the frame 1260 is illustrated. This fourth scheme will also be described with respect to the display system 1200 with the understanding that it is equally applicable to the display system 1000. This fourth scheme is substantially the same as the third scheme described above, except that fourth scheme utilizes two precisely positioned frame datums 1602 bonded onto the eye rim 1262 and a lens stack datum 1606 disposed on the lens stack 1230 for positioning both the waveguide 1220 and the lens stack 1230. In other words, similar to the first scheme, the lens stack datum 1606 is used to position the waveguide 1220.

[0147] The frame 1260 is formed with a plurality of frame datum holders 1604, in this case two frame datum holders 1604 on each eye rim 1262a, 1262b, circumferentially spaced apart on each of the eye rims 1262a, 1262b. The frame datum holders 1604 are the same or similar to the frame datum holders 1504. A lens stack datum 1606 is disposed on the front of each lens stack 1230 or lens stack assembly 1235 (such as on the front face of the lens stack barrel 1234).

[0148] Similar to the third scheme, the frame 1260 is installed on an assembly tool (not shown) having a plurality of jigs, pins and or posts to precisely position theframe 1260 on the assembly tool. The assembly tool also has a plurality of frame datum positioning posts located at the position of each frame datum holder 1602, and a lens datum positioning post located at the position of the lens stack datum when the frame 1260 is installed on the assembly tool and the lens stack 1230 or lens stack assembly 1235 is inserted into the projection lens barrel 1236. Each frame datum positioning post has a positioning surface precisely positioned at the proper height along the optical axis 1280 of a respective frame datum 1602 relative to the installed frame 1260. Each lens stack datum positioning post has a positioning surface precisely position at the proper height along the optical axis 1280 relative to the installed frame 1260. A respective frame datum 1602 is then installed in each frame datum holder 1604 such that the respective frame datum 1602 bears against the respective positioning surface of the respective frame datum positioning post. Each frame datum 1602 is bonded in place onto a respective frame datum holder 1604 using an adhesive bond 1506 at the position set by the assembly tool. The frame datums 1502 may be the same or similar to the frame datums 1502. The lens stack 1230 or lens stack assembly 1235 is inserted into the projection lens barrel 1236 such that the lens stack datum 1606 bears against the lens stack datum positioning post. The lens stack 1230 or lens stack assembly 1235 is bonded in place within the projection lens barrel 1236.

[0149] The waveguide 1220 (or waveguide assembly 1222, if utilized) is then inserted into the eye rim 1262 with the backside of the waveguide 1220 bearing against the respective frame datums 1602 and the lens stack datum 1606. As best shown in Figure 16C, the waveguide 1220 is then tacked in place to the eye rim 1262 using a tacking adhesive to form a plurality of circumferentially spaced tacking bonds 1406. For example,3, 4, 5 or more tacking bonds 1406 may be utilized. Next, the waveguide 1220 is bonded and sealed into the eye rim 1262 using a perimeter seal 1408 which may be applied in a plurality of segments between the tacking bonds 1406. The illuminator 1250 is then installed over the lens stack 1230 on the front side of the frame 1260. The illuminator 1250 is then installed which may be bonded to the eye rim 1262 of the frame 1260 or directly to the front side of the waveguide 1220 (as described in more detail herein). In the case of a binocular display system 1200, this assembly process is performed for both the left side and right side of the display assembly 1202.

[0150] In each of these positioning tolerance improvement schemes, the waveguide 1020, 1220 may comprise may comprises a stack of a plurality of individual waveguides. The individual waveguides are bonded together using a stacking adhesive between adjacent waveguides around the entire perimeter edge of the individual waveguides. For example, the width of the stacking adhesive may be about 800 pm or in the range of from 500 to 1000 pm. The frame datums 1302, 1402, 1502, 1602, and / or the lens stack datums 1304, 1606, are configured to be covered by the stacking adhesive when the waveguide 1020, 1220 is installed in the eye rim 1262 so it is not visible from the world side of the display system 1000, 1200. Furthermore, the eyepiece 1066, 1266 may also have surface gratings such as in-coupling and / or out-coupling gratings. The eyepiece 1066, 1266 may have a grating exclusion zone around the perimeter of the eyepiece 1066, 1266 such that the surface gratings do not contact the frame datums 1302, 1402, 1502, 1602, and / or the lens stack datums 1304, 1606.

[0151] Accordingly, improved schemes for improving the positioning tolerances between the lens stack (or lens stack assembly) and the waveguide for the displayassembly of a display system are disclosed herein. Each of these schemes can improve the positioning tolerance of the lens stack relative to the waveguide by 1.6 times. In other words, the positioning tolerance can be reduced by 38%. This improvement in the positioning tolerance of the lens stack relative to the waveguide results in significant improvement of the optical performance of the display system 1000, 1200 as measured by KPIs of the display system 1000, 1200. Therefore, each of the features and aspects of these improved schemes represents a technical improvement for XR display systems.

[0152] Turning now to Figures 17A-17E, features, aspects, and methods of manufacture for improving the precision, accuracy and manufacturability related to the interface between the illuminator and the waveguide will now be described. Again, these features, aspects and methods will also be described with respect to the display system 1200 with the understanding that it is equally applicable to the display system 1000. Similar to the relative position and orientation of the waveguide relative to lens stack, the assembly accuracy of the relative Z-position and pitch and yaw angle between the illuminator 1250 and the waveguide 1020 is also critical for the optical performance of the display assembly 1202 and the overall display system 1200, as measured by KPIs, and therefore the improvements disclosed herein constitute a technical improvement for XR display systems.

[0153] Referring to Fig. 17A, the illuminator 1250 comprises a circuit board 1702 having the light source 1210 disposed on the circuit board 1702. The light source comprises three LEDs 1211a, 1211 b, 1211 c mounted on the circuit board 1702. The circuit board 1702 may be formed of aluminum nitride, aluminum or other high thermal conductivity material such that the circuit board 1702 also functions as a heat sink toconduct heat away from the LEDs 1211. The electrical cable 1252 is connected to the circuit board 1702.

[0154] An illuminator base 1704 is attached to the bottom of the circuit board 1702 and covers the circuit board 1702. The illuminator base 1704 may be formed of plastic and the base 1704 has coupling optics 1205 (e.g., a coupling optic 1206 such as a CPC for each LED 1011 ) formed or installed in the base 1704. The illuminator base 1704 also has a plurality of illuminator datums 1706, in this case three illuminator datums 1706a, 1706b, 1706c, on the bottom of the base 1704. The illuminator datums 1706 may be molded into the base 1704, or they may be separate pucks attached to the base 1704. The illuminator datums 1706 may be positioned at the outside edges of the illuminator 1250 such that the illuminator datums 1706 are within the grating exclusion zone such illuminator datums 1706 do not contact the surface gratings on the waveguide 1220. The illuminator datums 1706 may also be positioned away from the antilaunch direction of the light traveling from the SLM 1240 into the waveguide 1220 because such light needs to be absorbed by the edge black or the perimeter bond 1408. The illuminator datums 1706 are configured to precisely position the Z-position and pitch and yaw angle relative to the waveguide 1220 when the illuminator 1250 is installed onto the waveguide 1220 with the illuminator datums 1706 contacting the surface of the world side of the waveguide 1220, as shown in Figures 17B-17D.

[0155] Figure 17B illustrates the assembly of the illuminator 1250 directly onto the waveguide 1220. The illuminator 1250 may be attached to the waveguide 1220 before or assembling the waveguide 1220 to the eye rim 1262 of the frame 1260. However, it may be more convenient to attach the waveguide 1220 to the waveguide after thewaveguide 1220 is attached to the eye rim 1262 because the electrical cable 1252 can get in the way of assembling the waveguide 1220 to the eye rim 1262. For example, if the illuminator 1250 is attached to the waveguide 1220 before installing the waveguide 1220 into the eye rim 1262, the electrical cable 1252 obstructs the dispensing of perimeter adhesive 1408 around the waveguide 1220 where the electrical cable 1252 extends over the edge of the eye rim 1262 (see e.g., Figure 14B and 14D). The illuminator 1250 is attached to the waveguide 1220 by applying adhesive 1708 around the edge of bottom of the illuminator base 1704 between the illuminator datums 1706. The illuminator 1250 is then placed onto the waveguide 1220 with the illuminator datums 1706 directly contacting the surface of the world side of the waveguide 1220. The illuminator datums 1706 precisely control the Z-position and pitch and yaw of the illuminator 1250 relative to the waveguide 1220, and in turn, relative to the rest of the display assembly 1202. Figures 17C and 17D illustrate the illuminator 1250 installed and bonded directly onto the waveguide 1220.

[0156] This direct bonding of the illuminator 1250 to the world side of an active layer waveguide 1220 allows the illuminator 1250 and the display assembly 1202 to be more compact than attaching the illuminator 1250 to the eye rim 1262. Directly bonding the illuminator 1250 to the waveguide 1220 eliminates the extra structure (e.g., flanges, bosses or the like) needed to attach the illuminator 1250 to the frame 1260. This alone can reduce the volume of the illuminator 1250 by 50%, or by 66%, or more. Moreover, in some prior XR display systems, the illuminator is typically located on the same side of the waveguide as the SLM such that a beam splitter is required. The placement of the illuminator 1250 on the world side of the waveguide 1220 opposite the SLM 1240 mountedon the user side of the waveguide eliminates the need for a beamsplitter, thereby significantly reducing the size of the overall display assembly 1202 compared to the displays of prior XR display systems. The use of direct bonding and illuminator datums 1706 also improves the accuracy (i.e. , reduces the tolerances) of the Z-position and pitch and yaw between the illuminator 1250 and the waveguide 1220 because it avoids stacking the tolerances between the illuminator 1250, the eye rim 1262 and the waveguide 1220 and the adhesive joints between each of these. For instance, the tolerance for the relative Z-position between the illuminator 1250 and the waveguide 1220 may be only 35 pm, or 50 pm, or less.

[0157] Certain aspects, advantages and features of the disclosure have been described herein. It is to be understood that not necessarily all such advantages may be achieved in accordance with any particular embodiment of the disclosure. Thus, the disclosure may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein.

[0158] Embodiments have been described in connection with the accompanying drawings. However, it should be understood that the figures are not drawn to scale. Distances, angles, etc. are merely illustrative and do not necessarily bear an exact relationship to actual dimensions and layout of the devices illustrated. In addition, the foregoing embodiments have been described at a level of detail to allow one of ordinary skill in the art to make and use the devices, systems, methods, and the like described herein. A wide variety of variation is possible. Components, elements, and / or steps may be altered, added, removed, or rearranged.

[0159] The devices and methods described herein can advantageously be at least partially implemented using, for example, computer software, hardware, firmware, or any combination of software, hardware, and firmware. Software modules can include computer executable code, stored in a computer’s memory, for performing the functions described herein. In some embodiments, computer-executable code is executed by one or more general purpose computers. However, a skilled artisan will appreciate, in light of this disclosure, that any module that can be implemented using software to be executed on a general purpose computer can also be implemented using a different combination of hardware, software, or firmware. For example, such a module can be implemented completely in hardware using a combination of integrated circuits. Alternatively or additionally, such a module can be implemented completely or partially using specialized computers designed to perform the particular functions described herein rather than by general purpose computers. In addition, where methods are described that are, or could be, at least in part carried out by computer software, it should be understood that such methods can be provided on non-transitory computer-readable media that, when read by a computer or other processing device, cause it to carry out the method.

[0160] While certain embodiments have been explicitly described, other embodiments will become apparent to those of ordinary skill in the art based on this disclosure.

[0161] The various processors and other electronic components described herein are suitable for use with any optical system for projecting light. The various processors and other electronic components described herein are also suitable for use with any audio system for receiving voice commands.

[0162] Various exemplary embodiments of the disclosure are described herein. Reference is made to these examples in a non-limiting sense. They are provided to illustrate more broadly applicable aspects of the disclosure. Various changes may be made to the disclosure described and equivalents may be substituted without departing from the true spirit and scope of the disclosure. In addition, many modifications may be made to adapt a particular situation, material, composition of matter, process, process act(s) or step(s) to the objective(s), spirit or scope of the present disclosure. Further, as will be appreciated by those with skill in the art, each of the individual variations described and illustrated herein has discrete components and features which may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope or spirit of the present disclosure. All such modifications are intended to be within the scope of claims associated with this disclosure.

[0163] The disclosure includes methods that may be performed using the subject devices. The methods may include the act of providing such a suitable device. Such provision may be performed by the end user. In other words, the “providing” act merely requires the end user obtain, access, approach, position, set-up, activate, power-up or otherwise act to provide the requisite device in the subject method. Methods recited herein may be carried out in any order of the recited events which is logically possible, as well as in the recited order of events.

[0164] Exemplary aspects of the disclosure, together with details regarding material selection and manufacture have been set forth above. As for other details of the present disclosure, these may be appreciated in connection with the above-referenced patents and publications as well as generally known or appreciated by those with skill in the art.The same may hold true with respect to method-based aspects of the disclosure in terms of additional acts as commonly or logically employed.

[0165] In addition, though the disclosure has been described in reference to several examples optionally incorporating various features, the disclosure is not to be limited to that which is described or indicated as contemplated with respect to each variation of the disclosure. Various changes may be made to the disclosure described and equivalents (whether recited herein or not included for the sake of some brevity) may be substituted without departing from the true spirit and scope of the disclosure. In addition, where a range of values is provided, it is understood that every intervening value, between the upper and lower limit of that range and any other stated or intervening value in that stated range, is encompassed within the disclosure.

[0166] Also, it is contemplated that any optional feature of the variations described may be set forth and claimed independently, or in combination with any one or more of the features described herein. Reference to a singular item, includes the possibility that there are plural of the same items present. More specifically, as used herein and in claims associated hereto, the singular forms “a,” “an,” “said,” and “the” include plural referents unless the specifically stated otherwise. In other words, use of the articles allow for “at least one” of the subject item in the description above as well as claims associated with this disclosure. It is further noted that such claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as “solely,” “only” and the like in connection with the recitation of claim elements, or use of a “negative” limitation.

[0167] Without the use of such exclusive terminology, the term “comprising” in claims associated with this disclosure shall allow for the inclusion of any additional element- irrespective of whether a given number of elements are enumerated in such claims, or the addition of a feature could be regarded as transforming the nature of an element set forth in such claims. Except as specifically defined herein, all technical and scientific terms used herein are to be given as broad a commonly understood meaning as possible while maintaining claim validity.

[0168] The breadth of the present disclosure is not to be limited to the examples provided and / or the subject specification, but rather only by the scope of claim language associated with this disclosure.

[0169] In the foregoing specification, the disclosure has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the disclosure. For example, the above-described process flows are described with reference to a particular ordering of process actions. However, the ordering of many of the described process actions may be changed without affecting the scope or operation of the disclosure. The specification and drawings are, accordingly, to be regarded in an illustrative rather than restrictive sense.

Claims

ClaimsWhat is claimed is:1 . An extended reality display system, comprising: a wearable frame structure configured to be worn on a head of a user, the frame structure including an eye rim for holding an eyepiece through which the user views images generated by the display system; a projection lens barrel formed integrally with the frame structure; and a lens stack for directing light for both illuminating at least a portion of a spatial light modulator (SLM) and projecting an image generated by the SLM to an eye of the user, the lens stack loaded directly into the projection lens barrel such that the lens stack is positioned on a user side of the eye rim.

2. The system of claim 1 , wherein the lens stack comprises a plurality of glass lenses stacked together to direct light to, and from the SLM.

3. The system of claim 1 , wherein the frame structure is formed a metal material.

4. The system of claim 3, wherein the metal is selected from the group consisting of magnesium, aluminum, an alloy of magnesium, an alloy of aluminum titanium, an alloy of titanium and a metal matrix composite.

5. The system of any of claims 1-4, further comprising:a waveguide installed in the eye rim such that the waveguide is positioned on the world side of the lens stack; an SLM mounted on the user side of the projection lens barrel; and an illuminator mounted on the world side of the eyepiece.

6. The system of claim 5, wherein the waveguide comprises a waveguide stack including a plurality of waveguide elements stacked together, and a cover glass installed on the waveguide stack.

7. The system of claim 5, wherein the waveguide comprises a waveguide stack including a plurality of waveguide elements stacked together, without a cover glass.

8. The system of claim 5, wherein the waveguide comprises a single plane waveguide configured to transmit multiple colors.

9. A kit for an extended reality display system, comprising: a wearable frame structure configured to be worn on a head of a user, the frame structure including an eye rim for holding an eyepiece through which the user views images generated by the display system; a plurality of frame datums circumferentially spaced apart around an inside perimeter of the eye rim, the frame configured to locate a waveguide in the eye rim;a lens stack datum disposed on the front side of a lens stack (the lens stack may solely comprise a stack of lenses or it may comprise a lens stack barrel with the stack of lenses inserted therein). a projection lens barrel formed integrally with the frame structure; and a projection lens barrel formed integrally with the frame structure; and a lens stack for directing light for both illuminating at least a portion of a spatial light modulator (SLM) and projecting an image generated by the SLM to an eye of the user, the lens stack configured to be installed in the projection lens barrel; a lens stack datum disposed on a front side of the lens stack; and a waveguide configured to be installed in the eye rim of the frame.

10. The kit of claim 9, wherein the frame datums are machined or molded into the frame structure.11 . The kit of claim 9, wherein the frame datums are elements separate from the frame and are bonded to the eye rim.

12. A method of assembling the kit of any of claims 9-11 into an extended reality display system, the method comprising: providing an assembly tool having jig frame datum and a jig lens stack datum, the jig frame datum configured to receive the frame datums and the jig lens stack datum configured to receive the lens stack datum;positioning the wearable frame structure on the assembly tool such that each of the frame datums is received on the jig frame datum; inserting the lens stack into the projection lens barrel until the lens stack datum is received on the jig lens stack datum; bonding the lens stack in place in the projection lens barrel using an adhesive; removing the frame structure from the assembly tool; installing the waveguide into the eye rim such a user side surface of the waveguide rests on each of the frame datums and the lens stack datum; bonding the waveguide in place in the eye rim using an adhesive.

13. The method of claim 12, further comprising: mounting an SLM mounted on a user side of the projection lens barrel; and mounting an illuminator on a world side of the waveguide.

14. The method of claim 13, wherein the illuminator is mounted, and directly bonded to, a surface of the world side of the waveguide.

15. The method of any of claims 12-14, wherein 6 the waveguide comprises a waveguide stack including a plurality of waveguide elements stacked together, and a cover glass installed on the waveguide stack.

16. The method of any of claims 12-14, wherein the waveguide comprises a waveguide stack including a plurality of waveguide elements stacked together, without a cover glass.

17. The method of any of claims 12-14, wherein the waveguide comprises a single plane waveguide configured to transmit multiple colors.

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