Multi-depth plane display system with reduced switching between depth planes

Abstract

To provide a favorable multi-depth plane display system with reduced switching between depth planes.SOLUTION: Methods and systems for reduction in switching between depth planes of a multi-depth plane display system are disclosed. The display system may be an augmented reality display system configured to provide virtual content on a plurality of depth planes using different wavefront divergences. The system may monitor the fixation points based upon the gaze of each of the user's eyes, with each fixation point being a three-dimensional location in the user's field of view. Location information of virtual objects to be presented to the user is obtained, with each virtual object being associated with a depth plane. In some embodiments, the depth plane on which the virtual object is to be presented is modified based upon the fixation point of the user's eyes.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] (Citation of Related Application) This application is a joint venture under §119(e) with U.S. Provisional Application No. 62 / 294,147, filed February 11, 2016 and entitled "AUGMENTED REALITY SYSTEMS AND METHODS UTILIZING VIEWER REFLECTIONS," U.S. Provisional Application No. 62 / 366,533, filed July 25, 2016 and entitled "AUGMENTED REALITY SYSTEMS AND METHODS UTILIZING REFLECTIONS," U.S. Provisional Application No. 62 / 440,336, filed December 29, 2016 and entitled "AUGMENTED REALITY SYSTEMS AND METHODS UTILIZING REFLECTIONS," and U.S. Provisional Application No. 62 / 445,630, filed January 12, 2017 and entitled "AUGMENTED REALITY SYSTEMS AND METHODS UTILIZING No. 62 / 366,599, filed July 25, 2016 and entitled "IMAGING MODIFICATION, DISPLAY AND VISUALIZATION USING AUGMENTED AND VIRTUAL REALITY EYEWEAR," U.S. Provisional Application No. 62 / 396,071, filed July 16, 2016 and entitled "IMAGING MODIFICATION, DISPLAY AND VISUALIZATION USING AUGMENTED AND VIRTUAL REALITY EYEWEAR," and U.S. Provisional Application No. 62 / 440,332, filed December 29, 2016 and entitled "IMAGING MODIFICATION, DISPLAY AND VISUALIZATION USING AUGMENTED AND VIRTUAL REALITY EYEWEAR," each of which is incorporated herein by reference for all purposes.

[0002] In addition, this application incorporates by reference the entirety of each of the following patent applications: U.S. Patent Application No. 14 / 555,585 (filed November 27, 2014), U.S. Patent Application No. 14 / 690,401 (filed April 18, 2015), U.S. Patent Application No. 14 / 212,961 (filed March 14, 2014), and U.S. Patent Application No. 14 / 331,218 (filed July 14, 2014).

[0003] (Field) The present disclosure relates to display systems, including augmented reality imaging and visualization systems. [Background technology]

[0004] Modern computing and display technologies have facilitated the development of systems for so-called "virtual reality" or "augmented reality" experiences, in which digitally reproduced images or portions thereof are presented to a user in a manner that appears or may be perceived as real. Virtual reality or "VR" scenarios typically involve the presentation of digital or virtual image information without transparency to other actual real-world visual inputs, while augmented reality or "AR" scenarios typically involve the presentation of digital or virtual image information as an extension to the visualization of the real world around the user. Mixed reality or "MR" scenarios are a type of AR scenario, typically involving virtual objects that are integrated into and responsive to the natural world. For example, MR scenarios may include AR image content that appears blocked by or is perceived to otherwise interact with objects in the real world.

[0005] Referring to FIG. 1, an augmented reality scene 10 is depicted. A user of the AR technology sees a real-world park-like setting 20 featuring people, trees, and buildings in the background, and a concrete platform 30. The user perceives that they are also "seeing" "virtual content," such as a robotic figure 40 standing on the real-world platform 30, and a flying cartoon-like avatar character 50 that appears to be an anthropomorphic bumblebee. These elements 50, 40 are "virtual" in that they do not exist in the real world. The human visual perception system is complex, and creating AR technology that facilitates a comfortable, natural-feeling, and rich presentation of virtual image elements among other virtual or real-world image elements is challenging.

[0006] The systems and methods disclosed herein address various challenges associated with AR or VR technology. Summary of the Invention [Means for solving the problem]

[0007] Some non-limiting embodiments include a system including one or more processors and one or more computer storage media storing instructions that, when executed by the one or more processors, cause the one or more processors to perform operations including determining a gaze point of an eye of a user, the gaze point being a three-dimensional location within the user's field of view, obtaining location information associated with a first virtual object to be presented to the user, the first virtual object having an associated depth from the user, adjusting one or more depth cues of the first virtual object to reduce a difference between the depth cues of the first virtual object and a depth cues for the gaze point, and causing presentation of the first virtual object to the user via a display device with the adjusted one or more depth cues.

[0008] In some other embodiments, a display system is provided. The display system includes a display device configured to present virtual objects to a user, each virtual object being on one or more depth planes of a plurality of depth planes, one or more processors, and one or more computer storage media storing instructions that, when executed by the display system, cause the display system to perform operations. The operations include monitoring information associated with a user's eye movements, determining a fixation point of the user's eyes based on the monitored information, each fixation point indicating a three-dimensional location being fixated by the user's eyes tracked over time, and adjusting the at least one virtual object based on the determined fixation points such that the at least one virtual object is displayed on a same depth plane corresponding to a depth plane region in which the determined fixation point is contained by more than a threshold metric. The determined fixation point is determined to be within the depth plane region by more than the threshold metric before adjusting the at least one virtual object.

[0009] An embodiment of a method is described. The method is performed by a system including one or more processors. The method includes determining a gaze point of an eye of a user, the gaze point being a three-dimensional location within a field of view of the user, obtaining location information associated with a first virtual object to be presented to the user, the first virtual object having an associated depth from the user, adjusting one or more depth cues of the first virtual object to reduce a difference between a depth cue of the first virtual object and a depth cue for the gaze point, and causing presentation of the first virtual object to the user via a display device with the adjusted one or more depth cues. The present invention provides, for example, the following: (Item 1) 1. A system comprising one or more processors and one or more computer storage media storing instructions that, when executed by the one or more processors, determining a gaze point of a user's eye, the gaze point being a three-dimensional location within the user's field of view; obtaining location information associated with a first virtual object to be presented to the user, the first virtual object having an associated depth from the user; and adjusting one or more depth cues of the first virtual object to reduce a difference between a depth cues of the first virtual object and a depth cues for the fixation point; causing a presentation of the first virtual object to the user via a display device with the adjusted one or more depth cues; and The system further comprises: (Item 2) Item 10. The system of item 1, wherein the depth cues comprise size, accommodation cues, and / or binocular cues. (Item 3) 2. The system of claim 1, wherein adjusting one or more depth cues includes aligning a depth plane corresponding to the adjusted one or more depth cues with a depth plane of the gaze point. (Item 4) The operations further include determining that the user is alternating a gaze point between the first virtual object and a second virtual object at a frequency that exceeds a threshold frequency; 4. The system of claim 3, wherein the gaze point coincides with a three-dimensional location of the second object, the second object being a virtual object or a real-world object. (Item 5) Item 1, the operations further including identifying that one or more depth cues for the first virtual object should be adjusted based on an indication of a user preference or based on a determination that the first virtual object is gazed upon less than a second object having a depth different from a depth associated with the first virtual object, the second object being a virtual object or a real-world object. (Item 6) Adjusting the one or more depth cues includes adjusting accommodation cues, the operations comprising: determining an accommodation-vergence mismatch associated with presentation of the first virtual object using the adjusted accommodation cue; and adjusting the binocular cues in response to said accommodation-vergence mismatch exceeding a threshold; Item 2. The system of item 1, further comprising: (Item 7) the display device further comprising a plurality of stacked waveguides; 2. The system of claim 1, wherein the plurality of stacked waveguides form a display area and provide a view of a surrounding environment through the display area, at least some of the plurality of waveguides are configured to output light with a wavefront divergence different from other waveguides, and each waveguide is associated with a depth plane. (Item 8) 8. The system of claim 7, wherein adjusting one or more depth cues includes varying a waveguide that outputs light to form the first virtual object. (Item 9) 1. A display system, comprising: a display device configured to present virtual objects to a user, each virtual object being on one or more of a plurality of depth planes; and one or more processors; one or more computer storage media having instructions stored thereon; Equipped with The instructions, when executed by the display system, monitoring information associated with eye movements of the user; determining eye fixation points of the user based on the monitored information, each fixation point indicating a three-dimensional location being gazed at by the user's eye and tracked over time; adjusting at least one virtual object based on the determined gaze point; and causing the display system to perform operations including The at least one virtual object is displayed on a same depth plane corresponding to a depth plane region that includes the determined gaze point, and the determined gaze point is determined to be contained within the depth plane region by more than a threshold metric. (Item 10) 10. The display system of item 9, wherein a fixation point at which the user gazes above a threshold metric corresponds to the location of a particular virtual object. (Item 11) 11. The display system of claim 10, wherein the operations further include identifying that the at least one virtual object should be adjusted based on a determination that the at least one virtual object is less gazed at than the particular object. (Item 12) 10. The display system of claim 9, wherein the fixation point at which the user gazes above a threshold metric corresponds to a location of a real-world object. (Item 13) 10. The display system of claim 9, wherein adjusting the at least one virtual object includes adjusting one or both of accommodation cues and binocular cues. (Item 14) The accommodation cue is adjusted, and the action comprises: determining an accommodation-vergence mismatch associated with presentation of the at least one virtual object using the adjusted accommodation cue; and adjusting the binocular cues in response to said accommodation-vergence mismatch exceeding a threshold; Item 14. The display system of item 13, further comprising: (Item 15) 10. The display system of claim 9, wherein the threshold metric comprises a threshold amount of time or a threshold frequency. (Item 16) 1. A method, comprising: A system with one or more processors can: determining a gaze point of a user's eye, the gaze point being a three-dimensional location within the user's field of view; obtaining location information associated with a first virtual object to be presented to the user, the first virtual object having an associated depth from the user; and adjusting one or more depth cues of the first virtual object to reduce a difference between a depth cues of the first virtual object and a depth cues for the fixation point; causing a presentation of the first virtual object to the user via a display device with the adjusted one or more depth cues; and A method comprising: (Item 17) Item 16. The method of item 15, wherein adjusting one or more depth cues includes matching a depth plane corresponding to the adjusted one or more depth cues with a depth plane of the fixation point. (Item 18) determining that the user alternates a gaze point between the first virtual object and a second object at a frequency above a threshold frequency, the second object being a virtual object or a real-world object; and adjusting the one or more depth cues; Item 16. The method of item 15, further comprising: (Item 19) Adjusting the one or more depth cues includes adjusting accommodation cues, the operations comprising: determining an accommodation-vergence mismatch associated with presentation of the first virtual object using the adjusted accommodation cue; and adjusting the binocular cues in response to said accommodation-vergence mismatch exceeding a threshold; Item 16. The method of item 15, further comprising: (Item 20) the display device comprises a plurality of stacked waveguides; the plurality of stacked waveguides form a display area and provide a view of a surrounding environment through the display area, at least some of the plurality of waveguides are configured to output light with a wavefront divergence different from other waveguides, each waveguide being associated with a depth plane; Item 16. The method of item 15, wherein adjusting one or more depth cues includes varying a waveguide that outputs light for forming the first virtual object. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 illustrates a user's view of an augmented reality (AR) device.

[0011] [Diagram 2] FIG. 2 illustrates an example of a wearable display system.

[0012] [Diagram 3] FIG. 3 illustrates a conventional display system for simulating a three-dimensional image for a user.

[0013] [Figure 4] FIG. 4 illustrates aspects of an approach for simulating a three-dimensional image using multiple depth planes.

[0014] [Diagram 5] 5A-5C illustrate the relationship between the radius of curvature and the radius of focus.

[0015] [Figure 6] FIG. 6 illustrates an example of a waveguide stack for outputting image information to a user.

[0016] [Figure 7] FIG. 7 illustrates an example of an output beam output by a waveguide.

[0017] [Figure 8] FIG. 8 illustrates an example of a stacked waveguide assembly where each depth plane contains an image formed using multiple different primary colors.

[0018] [Figure 9A] FIG. 9A illustrates an example of a cross-sectional side view of a pair of stacked waveguides, each of which includes an internal coupling optical element.

[0019] [Figure 9B] FIG. 9B illustrates a perspective view of the example of multiple stacked waveguides of FIG. 9A.

[0020] [Figure 9C] FIG. 9C illustrates a top-down plan view of the multiple stacked waveguide example of FIGS. 9A and 9B.

[0021] [Figure 10A] FIG. 10A illustrates an example of a representation of a user viewing content presented by a display system.

[0022] [Figure 10B] FIG. 10B illustrates another example of a representation of a user viewing content.

[0023] [Figure 11]FIG. 11 illustrates a representation of a user's field of view of a display system.

[0024] [Figure 12] FIG. 12 illustrates a flowchart of an example process for adjusting a perceived depth plane associated with a virtual object.

[0025] [Figure 13] FIG. 13 illustrates a flowchart of another example process for adjusting a perceived depth plane associated with a virtual object.

[0026] [Figure 14] FIG. 14 illustrates a flowchart of an example process for adjusting accommodation and binocular cues associated with a virtual object. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] An augmented reality display system may present virtual content to a user (or viewer), which appears to be located at a three-dimensional location in space within the user's field of view. The virtual content may also be referred to as a virtual object, which may include images, graphics, and other visual content that may be presented to the user by the display system. The display system may present different virtual objects at different depths or distances from the user, such that from the user's perspective, each virtual object may be associated with a three-dimensional location. The three-dimensional locations may correspond to a position on a horizontal axis, a position on a vertical axis, and a position on a depth axis away from the user. When a user switches from viewing a nearby virtual object to, for example, viewing a more distant virtual object, or vice versa, changes in vergence and / or accommodation may occur. As described in more detail below, vergence refers to a directional movement of the user's eyes, and accommodation refers to a change in the eye's lens and pupil (which may serve to focus light onto the eye's retina).

[0028] In some embodiments, techniques are provided for adjusting the presentation of virtual objects to limit the extent to which the user's visual system changes accommodation and / or changes vergence when the user views different virtual objects or combinations of virtual and real objects. For example, the presentation of the virtual object may be adjusted such that differences between one or more depth cues for the virtual object and corresponding depth cues for other virtual or real objects are reduced. For example, one or more depth cues for the virtual object may be adjusted to resemble corresponding depth cues for other virtual or real objects the user is viewing. The depth cues may include accommodation cues and / or binocular cues. As will be described, adjusting the accommodation cues of the virtual object may include adjusting the wavefront divergence of the light being output by the display system to the user, and adjusting the binocular cues may include adjusting the view of the virtual object being provided to each eye of the user (e.g., adjusting binocular disparity). Adjusting the view of the virtual object includes adjusting the binocularly separated presentation of the virtual object. In some embodiments, a user may switch between viewing two virtual objects presented at different depths and, after switching, comfortably view each of the virtual objects without having to change its accommodative response for each virtual object.

[0029] Utilizing the techniques described herein, the perceived presentation quality of virtual content may be improved. For example, perceptible visual artifacts such as flicker caused by switching content between different depth planes may be reduced, especially when certain augmented reality display systems, such as variable focus display systems as described further herein, are utilized. As another example, fast switching of gaze between a virtual object and another virtual or real object may be facilitated by reducing the need for the user to change accommodation between those objects. For example, changes in accommodation may take a perceptible amount of time as the user's eyes focus, which may impair the user experience, for example, by slowing down the user's ability to absorb information as the user repeatedly switches his or her attention between two objects. This slowdown may be undesirable in situations such as, for example, games where rapid user reactions are the basis of competitive play. Other example situations include high-speed environments that require multitasking and / or high levels of attention, such as operating rooms.

[0030] With respect to a variable focus display system, it should be understood that such a system may present virtual content in separate depth planes, with all virtual content being presented in the same depth plane for each frame presented to the user (e.g., only one depth plane is active or outputs image information at a time). As will be described, a variable focus display system may determine a three-dimensional gaze point at which a user is gazing, and based on the gaze point, select a depth plane in which to present all virtual content. As an example of determining a gaze point, the display system may monitor the orientation and / or shape of the user's eyes and determine a three-dimensional location where the determined line of sight of each of the eyes intersect. The display system may determine that the user is viewing a particular virtual object being presented at a particular three-dimensional location, and the display system may present all virtual content in a depth plane corresponding to that three-dimensional location. In this way, the display system may ensure that the particular virtual object, and optionally other virtual content, is in focus for the user. When presenting virtual content in the next selected depth plane, perceptible flicker may be introduced, for example, when the display system presents virtual content in the next selected depth plane and then switches back to the previous depth plane again. For example, when a user modifies their eyes to gaze at a next fixation point, the display system may select the next depth plane and present the virtual content in the next presented frame. Errors in determining the fixation point and / or a fixation point near an interface between depth planes may cause undesirable and / or random switching back and forth between depth planes. As will be described below with respect to FIG. 11, each depth plane may encompass a particular range of depths from the user, whereby the depth plane may be selected according to the three-dimensional location at which the user's eyes are gazed.

[0031] To present virtual content at distinct depth planes, the display system may include one or more waveguides configured to output light with different wavefront divergences corresponding to the different depth planes. Using the different wavefront divergences, different accommodation cues may be provided to the user, and the display system may cause a first virtual object to appear to be located at a first depth in the user's field of view, while a second virtual object may appear to be located at a second depth in the user's field of view (using light with different wavefront divergences). In addition, the display system may present different images to each eye of the user. For example, the display system may be a binocular display that presents slightly different views of a virtual object to each eye, each view corresponding to a view of the virtual object by each respective eye at a given depth plane. That is, the display system may provide a binocularly separated presentation of the virtual object to the eyes, such that depth may be represented, in part, through binocular disparity. Thus, the virtual object may be perceived by the user to be at different depths based on the output wavefront divergences and the views of the different virtual objects provided to each eye.

[0032] The variable focus display system, as described above, may therefore present all virtual content using a particular wavefront divergence (corresponding to a particular depth plane) for each frame. As the user modifies his or her gaze point, light with a different wavefront divergence may be selected to present other virtual content on other depth planes. It should be understood that a user switching his or her gaze point between two objects on different depth planes may cause rapid and repeated switching between the depth planes, which may be perceived by the user as flickering, since different depth planes are active at different times. In addition, as described herein, there may be a momentary delay in the user's viewing of the content as the accommodation of the eye changes.

[0033] The techniques described herein may be advantageously utilized to reduce the occurrence of flicker and / or delays in viewing content caused by depth plane switching and / or display system initiated changes in the user's accommodation. It should be understood that the display system may have access to a map or database indicating where various virtual objects may be placed in three-dimensional space. In some embodiments, the display system may determine that the user is switching between viewing a first virtual object and viewing either (1) a second virtual object or (2) a real-world object that is located in a different depth plane (e.g., more distant or closer) than the first virtual object. The display system may then cause the objects to be presented in the same depth plane. For example, the display system may cause the first virtual object and the second virtual object to be output with the same or similar wavefront divergence (e.g., presented through the same waveguide) regardless of whether the user is gazing at the first virtual object or the second virtual object. In addition, the display system may cause the first virtual object to be output with a wavefront divergence associated with the depth of the real-world object. In some other embodiments, the display system may first determine the depth plane at which the user is gazing and modify the depth plane indicated by the display system's map before outputting the virtual content.

[0034] In some embodiments, the display system may reduce switching in the user's accommodation response by adjusting the output wavefront divergence such that the virtual object is presented with the same wavefront divergence (corresponding to the same depth plane) as another virtual object or a real object while preserving (e.g., not accommodating) the view of the virtual object provided to each eye. Without being limited by theory, because the view of the virtual object is not modified, the perceived location in three-dimensional space may be preserved based on binocular cues (e.g., binocular disparity). As a result, the perceived three-dimensional location may be maintained while avoiding changes in accommodation. However, as will be explained, modifying the wavefront divergence of a virtual object while preserving the same view of the virtual object presented to each eye may result in negative physiological responses (e.g., headaches, eye strain, fatigue, etc.) due to a mismatch between the perceived depth associated with the modified wavefront divergence and the perceived depth associated with binocular disparity. The perceived depth (e.g., in diopters) associated with a particular wavefront divergence and the perceived depth (e.g., in diopters) associated with the binocular disparity may be determined by the display system, and the mismatch between these two values ​​may be calculated to determine an accommodation-vergence mismatch. In some embodiments, the display system may take additional action (in addition to modifying the output wavefront divergence) if the mismatch exceeds a threshold (e.g., 0.33 diopters). As an example, the display system may adjust the binocular disparity, e.g., modify the view of a virtual object provided to each eye, to correspond to the depth plane associated with the wavefront divergence.

[0035] Optionally, the display system may adjust the binocular disparity of a virtual object without modifying the wavefront divergence of the virtual object, i.e., in contrast to a display system that adjusts the wavefront divergence to limit how often a user accommodates a virtual object, the display system may adjust the binocular disparity so that the virtual object is perceived to be at the same or a similar depth plane as other objects.

[0036] Although a variable focus display system is described in the above section, other display systems referenced herein, such as a multifocal display system, may also be utilized. A multifocal display system may simultaneously output light with wavefront divergences associated with multiple different depth planes, such that content is displayed on multiple depth planes simultaneously for each frame presented to a user. Because a multifocal display system may present virtual objects at different depth planes in the same frame, the multifocal display system may avoid introducing certain visual artifacts (e.g., flicker) when a user switches their view to different virtual objects. However, utilizing techniques described herein, such as adjusting the depth plane at which a virtual object is presented, the need to change accommodation may be reduced consistent with the above description.

[0037] It should be understood that the display system may be part of an augmented reality display system or a virtual reality display system. As one example, the display system may be transparent, allowing the user to view the real world while providing the user with virtual content in the form of images, videos, interactions, etc. As another example, the display system may block the user's view of the real world, and virtual reality images, videos, interactions, etc. may be presented to the user.

[0038] It should also be appreciated that the various embodiments described herein may be advantageously provided in a variety of contexts. By way of example, the techniques and systems disclosed herein may be applied to a health care context, where virtual objects may be viewed in conjunction with real objects. For example, a surgeon may perform surgery on a real patient while wearing a display system. The display system may advantageously present medical information to the surgeon, such as heart rate information. The display system may cause the medical information to be presented on the depth plane closest to the patient, such that the surgeon may avoid the need to switch accommodation between the patient and the medical information while performing his or her duties. As another example, a user may play a race car driving game while wearing a display system. The display system may present virtual content, such as the interior of the user's car and the exterior of the car (e.g., road, competitor's car). The display system may adjust certain virtual content (e.g., view through the car's windshield), such as a speedometer, to be presented on the same depth plane as the exterior of the car or the competitor's car. In this way, a user may easily and quickly view their speed while avoiding the need to look at the dashboard of a car and change accommodation to the speedometer each time they view the speedometer. Additionally, flicker may be eliminated when a user views the speedometer, which may otherwise adversely affect game play.

[0039] Now, reference is made to the figure.

[0040] FIG. 2 illustrates an example of a wearable display system 60. The display system 60 includes a display 70 and various mechanical and electronic modules and systems to support the functionality of the display 70. The display 70 may be coupled to a frame 80 that is wearable by a display system user or viewer 90 and configured to position the display 70 in front of the eye of the user 90. The display 70 may be considered eyewear in some embodiments. In some embodiments, a speaker 100 is coupled to the frame 80 and configured to be positioned adjacent to the ear canal of the user 90 (in some embodiments, another speaker, not shown, may optionally be positioned adjacent the user's other ear canal to provide stereo / shapeable sound control). The display system may also include one or more microphones 110 or other devices to detect sound. In some embodiments, the microphone may be configured to allow a user to provide input or commands to the system 60 (e.g., voice menu command selection, natural language questions, etc.) and / or audio communication with other persons (e.g., other users of a similar display system). The microphone may be further configured as an ambient sensor to collect audio data (e.g., sounds from the user and / or the environment). In some embodiments, the display system may also include an ambient sensor 120a, which may be separate from the frame 80 and attached to the body of the user 90 (e.g., on the head, torso, limbs, etc. of the user 90). The ambient sensor 120a, in some embodiments, may be configured to obtain data characterizing a physiological state of the user 90. For example, the sensor 120a may be an electrode.

[0041] 2, the display 70 is operably coupled to the local data processing module 140 by a communication link 130, such as a wired lead or wireless connectivity, which may be mounted in a variety of configurations, such as fixedly attached to the frame 80, fixedly attached to a helmet or hat worn by the user, embedded within headphones, or otherwise removably attached to the user 90 (e.g., in a backpack-type configuration, belt-type configuration). Similarly, the sensor 120a may be operably coupled to the local data processing module 140 by a communication link 120b, such as a wired lead or wireless connectivity. The local processing and data module 140 may comprise a hardware processor and digital memory, such as non-volatile memory (e.g., flash memory or hard disk drive), both of which may be utilized to aid in processing, caching, and storing data. Optionally, the local processing and data module 140 may include one or more central processing units (CPUs), graphics processing units (GPUs), dedicated processing hardware, and the like. The data includes a) data captured from sensors (such as image capture devices (cameras, etc.), microphones, inertial measurement units, accelerometers, compasses, GPS units, wireless devices, gyroscopes, and / or other sensors disclosed herein (which may be operatively coupled to the frame 80 or otherwise attached to the user 90, for example)) and / or b) data acquired and / or processed using the remote processing module 150 and / or remote data repository 160 (including data related to the virtual content), potentially for transfer to the display 70 after processing or retrieval. The local processing and data module 140 may be operatively coupled to the remote processing module 150 and the remote data repository 160 by communication links 170, 180, such as via wired or wireless communication links, such that these remote modules 150, 160 are operatively coupled to each other and available as resources to the local processing and data module 140.In some embodiments, local processing and data module 140 may include one or more of an image capture device, a microphone, an inertial measurement unit, an accelerometer, a compass, a GPS unit, a wireless device, and / or a gyroscope. In some other embodiments, one or more of these sensors may be mounted on frame 80 or may be a freestanding structure that communicates with local processing and data module 140 by a wired or wireless communication path.

[0042] With continued reference to FIG. 2, in some embodiments, remote processing module 150 may comprise one or more processors configured to analyze and process data and / or image information, including, for example, one or more central processing units (CPUs), graphics processing units (GPUs), dedicated processing hardware, etc. In some embodiments, remote data repository 160 may comprise digital data storage facilities that may be available through the Internet or other networking configurations in a "cloud" resource configuration. In some embodiments, remote data repository 160 may include one or more remote servers that provide information, for example, information for generating augmented reality content to local processing and data module 140 and / or remote processing module 150. In some embodiments, all data is stored and all computations are performed within the local processing and data module, allowing for fully autonomous use from the remote modules. Optionally, an external system (e.g., a system of one or more processors, one or more computers), including a CPU, GPU, etc., may perform at least a portion of the processing (e.g., generate image information, process data) and provide information to and receive information from modules 140, 150, 160, e.g., via a wireless or wired connection.

[0043] Referring now to FIG. 3, the perception of an image as "three-dimensional" or "3-D" may be achieved by providing a slightly different presentation of the image to each eye of a viewer. FIG. 3 illustrates a conventional display system for simulating a three-dimensional image for a user. Two different images 190, 200 (one for each eye 210, 220) are output to the user to provide binocular cues, which the user's visual system interprets and derives the perception of depth. The images 190, 200 are spaced from the eyes 210, 220 by a distance 230 along an optical axis or z-axis parallel to the viewer's line of sight. The images 190, 200 are flat, and the eyes 210, 220 may focus on the images by assuming a single accommodated state. Such a 3-D display system relies on the human visual system to combine the images 190, 200 and provide the perception of depth and / or scale for the combined image.

[0044] However, it should be understood that the human visual system is more complex and providing a realistic perception of depth is more difficult. For example, many viewers of conventional "3-D" display systems find such systems uncomfortable or may not perceive any sense of depth at all. Without being limited by theory, it is believed that viewers of an object may perceive the object as "three-dimensional" due to a combination of vergence and accommodation. Vergence movement of the two eyes relative to each other (e.g., eye rotation, in which the pupils move toward or away from each other to converge the line of sight of the eyes and fixate on the object) is closely linked to the focusing (or "accommodation") of the eye lens and pupil. Under normal conditions, changing the focus of the eye lens or accommodating the eye to change focus from one object to another at different distances will automatically produce a matching change in vergence to the same distance, under a relationship known as the "accommodation-vergence reflex" and pupil dilation or constriction. Similarly, changes in vergence will induce matching changes in accommodation of lens shape and pupil size under normal conditions. As described herein, many stereoscopic or "3-D" display systems display a scene using a slightly different presentation (and therefore a slightly different image) to each eye so that a three-dimensional perspective is perceived by the human visual system. However, such systems are uncomfortable for many viewers, especially since they simply provide a different presentation of the scene, but the eyes view the entire image information in a single accommodated state, working against the "accommodation-vergence reflex." Display systems that provide better matching between accommodation and vergence can create a more realistic and comfortable simulation of a three-dimensional image.

[0045] FIG. 4 illustrates aspects of an approach for simulating a three-dimensional image using multiple depth planes. With reference to FIG. 4, objects at various distances from the eyes 210, 220 on the z-axis are accommodated by the eyes 210, 220 such that the objects are in focus. The eyes 210, 220 assume a particular accommodated state and focus on objects at different distances along the z-axis. As a result, a particular accommodated state is said to be associated with a particular one of the depth planes 240 having an associated focal length, and an object or part of an object at a particular depth plane is in focus when the eye is in an accommodated state for that depth plane. In some embodiments, a three-dimensional image may be simulated by providing different presentations of images for each of the eyes 210, 220, and may also be simulated by providing different presentations of images corresponding to each of the depth planes. Although shown as separate for clarity of illustration, it should be understood that the fields of view of the eyes 210, 220 may overlap, for example, as the distance along the z-axis increases. Additionally, while shown as flat for ease of illustration, it should be understood that the contour of the depth plane may be curved in physical space such that all features within the depth plane are in focus with the eye in a particular accommodated state.

[0046] The distance between an object and the eye 210 or 220 may also change the amount of divergence of light from that object as viewed by that eye. Figures 5A-5C illustrate the relationship between distance and divergence of light rays. The distance between the object and the eye 210 is represented in the order of decreasing distances R1, R2, and R3. As shown in Figures 5A-5C, the light rays become more divergent as the distance to the object decreases. As the distance increases, the light rays become more collimated. In other words, the light field generated by a point (an object or part of an object) may be said to have a spherical wavefront curvature that is a function of the distance the point is away from the user's eye. The curvature increases with decreasing distance between the object and the eye 210. As a result, at different depth planes, the divergence of the light rays is also different, and the divergence increases with decreasing distance between the depth plane and the viewer's eye 210. Although only a monocular 210 is illustrated in FIGS. 5A-5C and various other figures herein for clarity of illustration, it should be understood that the discussion regarding eye 210 may apply to both eyes 210 and 220 of a viewer.

[0047] Without being limited by theory, it is believed that the human eye is typically capable of interpreting a finite number of depth planes to provide depth perception. As a result, a highly realistic simulation of perceived depth may be achieved by providing the eye with different presentations of images corresponding to each of these limited number of depth planes. The different presentations may be focused separately by the viewer's eyes, thereby serving to provide depth cues to the user based on ocular accommodation required to focus on different image features for a scene located on different depth planes and / or based on observing different image features on different depth planes that are out of focus.

[0048] FIG. 6 illustrates an example of a waveguide stack for outputting image information to a user. The display system 250 includes a stack of waveguides or a stacked waveguide assembly 260 that may be utilized to provide a three-dimensional perception to the eye / brain using multiple waveguides 270, 280, 290, 300, 310. In some embodiments, the display system 250 is the system 60 of FIG. 2, and FIG. 6 illustrates several portions of the system 60 in greater detail. For example, the waveguide assembly 260 may be part of the display 70 of FIG. 2. It should be understood that the display system 250 may be considered a bright field display in some embodiments.

[0049] Continuing with reference to FIG. 6, the waveguide assembly 260 may include a number of features 320, 330, 340, 350 between the waveguides. In some embodiments, the features 320, 330, 340, 350 may be one or more lenses. The waveguides 270, 280, 290, 300, 310 and / or the number of lenses 320, 330, 340, 350 may be configured to transmit image information to the eye with various levels of wavefront curvature or light beam divergence. Each waveguide level may be associated with a particular depth plane and may be configured to output image information corresponding to that depth plane. The image input devices 360, 370, 380, 390, 400 may act as light sources for the waveguides and may be utilized to input image information into the waveguides 270, 280, 290, 300, 310, each configured to distribute incident light through each respective waveguide for output toward the eye 210, as described herein. The light exits output surfaces 410, 420, 430, 440, 450 of the image input devices 360, 370, 380, 390, 400 and is input into corresponding input surfaces 460, 470, 480, 490, 500 of the waveguides 270, 280, 290, 300, 310. In some embodiments, each of the input surfaces 460, 470, 480, 490, 500 may be an edge of the corresponding waveguide or may be a portion of the major surface of the corresponding waveguide (i.e., one of the waveguide surfaces that directly faces the world 510 or the viewer's eye 210). In some embodiments, a single beam of light (e.g., a collimated beam) may be launched into each waveguide and output a total field of cloned collimated beams that are directed toward the eye 210 at a particular angle (and divergence) corresponding to the depth plane associated with the particular waveguide. In some embodiments, a single one of the image launch devices 360, 370, 380, 390, 400 may be associated with and launch light into multiple (e.g., three) waveguides 270, 280, 290, 300, 310.

[0050] In some embodiments, the image input devices 360, 370, 380, 390, 400 are individual displays that each generate image information for input into a corresponding waveguide 270, 280, 290, 300, 310. In some other embodiments, the image input devices 360, 370, 380, 390, 400 are the output of a single multiplexed display that may, for example, send image information via one or more optical conduits (such as fiber optic cables) to each of the image input devices 360, 370, 380, 390, 400. It should be understood that the image information provided by the image input devices 360, 370, 380, 390, 400 may include light of different wavelengths or colors (e.g., different primary colors as discussed herein).

[0051] In some embodiments, the light injected into the waveguides 270, 280, 290, 300, 310 is provided by a light projector system 520, which includes a light module 530, which may include a light emitter such as a light emitting diode (LED). Light from the light module 530 may be directed through a beam splitter 550 to and modified by a light modulator 540, e.g., a spatial light modulator. The light modulator 540 may be configured to change the perceived intensity of the light injected into the waveguides 270, 280, 290, 300, 310. Examples of spatial light modulators include liquid crystal displays (LCDs), including liquid crystal on silicon (LCOS) displays.

[0052] In some embodiments, the display system 250 may be a scanning fiber display comprising one or more scanning fibers configured to project light in various patterns (e.g., raster scan, spiral scan, Lissajous pattern, etc.) into one or more waveguides 270, 280, 290, 300, 310 and ultimately to the viewer's eye 210. In some embodiments, the illustrated image injection devices 360, 370, 380, 390, 400 may diagrammatically represent a single scanning fiber or a bundle of scanning fibers configured to inject light into one or more waveguides 270, 280, 290, 300, 310. In some other embodiments, the illustrated image injection devices 360, 370, 380, 390, 400 may diagrammatically represent multiple scanning fibers or multiple bundles of scanning fibers, each configured to inject light into an associated one of the waveguides 270, 280, 290, 300, 310. It is understood that one or more optical fibers may be configured to transmit light from the optical module 530 to one or more of the waveguides 270, 280, 290, 300, 310. It is understood that one or more intervening optical structures may be provided between the scanning fiber or fibers and one or more of the waveguides 270, 280, 290, 300, 310, for example, to redirect light exiting the scanning fiber into one or more of the waveguides 270, 280, 290, 300, 310.

[0053] The controller 560 controls the operation of one or more of the stacked waveguide assemblies 260, including the operation of the image input devices 360, 370, 380, 390, 400, the light source 530, and the light module 540. In some embodiments, the controller 560 is part of the local data processing module 140. The controller 560 includes programming (e.g., instructions in a non-transient medium) that coordinates the timing and provisioning of image information to the waveguides 270, 280, 290, 300, 310, for example, according to any of the various schemes disclosed herein. In some embodiments, the controller may be a single integrated device or a distributed system connected by wired or wireless communication channels. The controller 560 may be part of the processing module 140 or 150 (FIG. 2) in some embodiments.

[0054] Continuing with reference to FIG. 6, the waveguides 270, 280, 290, 300, 310 may be configured to propagate light within each respective waveguide by total internal reflection (TIR). Each of the waveguides 270, 280, 290, 300, 310 may be planar with major top and bottom surfaces and edges extending between their major top and bottom surfaces, or may have another shape (e.g., curved). In the illustrated configuration, each of the waveguides 270, 280, 290, 300, 310 may include out-coupling optical elements 570, 580, 590, 600, 610 configured to extract light out of the waveguide by redirecting light propagating within each respective waveguide out of the waveguide and outputting image information to the eye 210. The extracted light may also be referred to as out-coupled light, and the out-coupling optical elements may also be referred to as light extraction optical elements. The extracted beam of light may be output by the waveguide where the light propagating within the waveguide strikes the light extraction optical element. The outcoupling optical element 570, 580, 590, 600, 610 may be, for example, a grating including diffractive optical features as further discussed herein. Although shown disposed on the bottom major surface of the waveguide 270, 280, 290, 300, 310 for ease of explanation and clarity of the drawings, in some embodiments the outcoupling optical element 570, 580, 590, 600, 610 may be disposed on the top and / or bottom major surfaces and / or directly within the volume of the waveguide 270, 280, 290, 300, 310 as further discussed herein. In some embodiments, the outcoupling optical elements 570, 580, 590, 600, 610 may be attached to a transparent substrate and formed within a layer of material that forms the waveguide 270, 280, 290, 300, 310. In some other embodiments, the waveguide 270, 280, 290, 300, 310 may be a monolithic piece of material and the outcoupling optical elements 570, 580, 590, 600, 610 may be formed on a surface of and / or within that piece of material.

[0055] With continued reference to FIG. 6, as discussed herein, each waveguide 270, 280, 290, 300, 310 is configured to output light and form an image corresponding to a particular depth plane. For example, the waveguide 270 closest to the eye may be configured to deliver collimated light (injected into such waveguide 270) to the eye 210. The collimated light may represent an optical infinity focal plane. The next upper waveguide 280 may be configured to send collimated light that passes through a first lens 350 (e.g., a negative lens) before it can reach the eye 210. Such a first lens 350 may be configured to generate a slight convex wavefront curvature such that the eye / brain interprets the light originating from the next upper waveguide 280 as originating from a first focal plane that is closer inward from optical infinity toward the eye 210. Similarly, the third upper waveguide 290 passes its output light through both the first 350 and second 340 lenses before reaching the eye 210. The combined refractive powers of the first 350 and second 340 lenses may be configured to produce another incremental amount of wavefront curvature such that the eye / brain interprets the light originating from the third waveguide 290 as originating from a second focal plane that is even closer inward from optical infinity towards the person than the light from the next upper waveguide 280.

[0056] The other waveguide layers 300, 310 and lenses 330, 320 are similarly configured, with the highest waveguide 310 in the stack sending its output through all of the lenses between it and the eye for an aggregate focal power that represents the focal plane closest to the person. To compensate the stack of lenses 320, 330, 340, 350 when viewing / interpreting light originating from the world 510 on the other side of the stacked waveguide assembly 260, a compensating lens layer 620 may be placed on top of the stack to compensate for the aggregate power of the lens stacks 320, 330, 340, 350 below. Such a configuration provides as many perceived focal planes as there are waveguide / lens pairs available. Both the outcoupling optical elements of the waveguides and the focusing sides of the lenses may be static (i.e., not dynamic or electroactive). In some alternative embodiments, one or both may be dynamic using electroactive features.

[0057] In some embodiments, two or more of the waveguides 270, 280, 290, 300, 310 may have the same associated depth plane. For example, multiple waveguides 270, 280, 290, 300, 310 may be configured to output images set at the same depth plane, or multiple subsets of the waveguides 270, 280, 290, 300, 310 may be configured to output images set at the same depth planes, one set for each depth plane. This may provide the advantage of forming tiled images to provide an extended field of view at those depth planes.

[0058] Continuing with reference to FIG. 6, the outcoupling optical elements 570, 580, 590, 600, 610 may be configured to redirect light from their respective waveguides and output this light with an appropriate amount of divergence or collimation for a particular depth plane associated with the waveguide. As a result, waveguides with different associated depth planes may have different configurations of outcoupling optical elements 570, 580, 590, 600, 610 that output light with different amounts of divergence depending on the associated depth plane. In some embodiments, the light extraction optical elements 570, 580, 590, 600, 610 may be volume or surface features that may be configured to output light at a particular angle. For example, the light extraction optical elements 570, 580, 590, 600, 610 may be volume holograms, surface holograms, and / or diffraction gratings. In some embodiments, the features 320, 330, 340, 350 may not be lenses. Rather, they may simply be spacers (eg, cladding layers and / or structures for forming air gaps).

[0059] In some embodiments, the outcoupling optical elements 570, 580, 590, 600, 610 are diffractive features that form a diffraction pattern or "diffractive optical elements" (also referred to herein as "DOEs"). Preferably, the DOEs have a sufficiently low diffraction efficiency so that only a portion of the light in the beam is deflected towards the eye 210 at each intersection of the DOE, while the remainder continues to travel through the waveguide via TIR. The light carrying the image information is thus split into several related exit beams that exit the waveguide at various locations, and the result is a very uniform pattern of exit emission towards the eye 210 for this particular collimated beam bouncing within the waveguide.

[0060] In some embodiments, one or more DOEs may be switchable between an "on" state in which they actively diffract and an "off" state in which they do not significantly diffract. For example, a switchable DOE may comprise a layer of polymer dispersed liquid crystal in which microdroplets comprise a diffractive pattern in a host medium, and the refractive index of the microdroplets may be switched to substantially match that of the host material (in which case the pattern does not significantly diffract incident light), or the microdroplets may be switched to a refractive index that does not match that of the host medium (in which case the pattern actively diffracts incident light).

[0061] In some embodiments, a camera assembly 630 (e.g., a digital camera, including visible and infrared light cameras) may be provided to capture images of the eye 210 and / or tissue surrounding the eye 210, for example, to detect user input and / or to monitor a physiological condition of the user. As used herein, a camera may be any image capture device. In some embodiments, the camera assembly 630 may include an image capture device and a light source for projecting light (e.g., infrared light) onto the eye, which may then be reflected by the eye and detected by the image capture device. In some embodiments, the camera assembly 630 may be mounted on the frame 80 (FIG. 2) and in electrical communication with the processing modules 140 and / or 150, which may process image information from the camera assembly 630. In some embodiments, one camera assembly 630 may be utilized for each eye to monitor each eye separately.

[0062] In some embodiments, the inward-facing camera may also be configured to detect the accommodative response or state of the user's eyes and display display content to the user without requiring the user to change their accommodative response. Optionally, the inward-facing camera may be configured to detect the accommodative response or state of each of the user's eyes. The displayed content may include alerts, menu items, or other content that may be beneficial to be clearly visible to the user regardless of the depth at which the eye is focused. In some embodiments, the display system 80 may be configured to detect shape changes of the lens in the user's eye to determine the object at which the user's eye is focused, and in turn, the display system 80 may render the displayed image on the appropriate depth plane with the corresponding appropriate depth cues (e.g., with the appropriate resolution, detail, color saturation, contrast, etc. for the particular depth plane).

[0063] 7, an example of an exit beam output by a waveguide is shown. Although one waveguide is illustrated, it should be understood that other waveguides in the waveguide assembly 260 (FIG. 6) may function similarly and that the waveguide assembly 260 includes multiple waveguides. Light 640 is launched into the waveguide 270 at the input surface 460 of the waveguide 270 and propagates within the waveguide 270 by TIR. At the point where the light 640 impinges on the DOE 570, a portion of the light exits the waveguide as an exit beam 650. The exit beams 650 are illustrated as approximately parallel, but as discussed herein, they may be redirected to propagate to the eye 210 at an angle (e.g., forming a diverging exit beam) depending on the depth plane associated with the waveguide 270. It should be understood that a nearly collimated exit beam may refer to a waveguide with outcoupling optics that outcouples light to form an image that appears to be set at a depth plane at a large distance (e.g., optical infinity) from the eye 210. Other sets of waveguides or other outcoupling optics may output a more divergent exit beam pattern, which would require the eye 210 to accommodate to a closer distance and focus on the retina, and would be interpreted by the brain as light from a distance closer to the eye 210 than optical infinity.

[0064] In some embodiments, a full color image may be formed at each depth plane by overlaying an image on each of the primary colors, for example, three or more primary colors. FIG. 8 illustrates an example of a stacked waveguide assembly, where each depth plane includes an image formed using multiple different primary colors. The illustrated embodiment shows depth planes 240a-240f, but more or less depths are also contemplated. Each depth plane may have three or more primary color images associated with it, including 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 different depth planes are indicated in the diagram by different numbers for diopters following the letters G, R, and B. By way of example only, the numbers following each of these letters indicate the diopters (1 / m), i.e., the inverse distance of the depth plane from the viewer, and each box in the diagram represents an individual primary color image. In some embodiments, the exact location of the depth planes for the different primary colors may be varied to account for differences in the eye's focusing of different wavelengths of light. For example, different primary color images for a given depth plane may be placed on depth planes corresponding to different distances from the user. Such an arrangement may increase visual acuity and user comfort and / or reduce chromatic aberration.

[0065] In some embodiments, the light of each primary color may be output by a single dedicated waveguide, such that each depth plane may have multiple waveguides associated with it. In such embodiments, each box in the figure containing the letter G, R, or B may be understood to represent an individual waveguide, and three waveguides may be provided per depth plane, with three primary color images provided per depth plane. The waveguides associated with each depth plane are shown adjacent to each other in this drawing for ease of illustration, but it should be understood that in a physical device, the waveguides may all be arranged in a stack with one waveguide per level. In some other embodiments, multiple primary colors may be output by the same waveguide, such that, for example, only a single waveguide may be provided per depth plane.

[0066] 8, in some embodiments, G is green, R is red, and B is blue. In some other embodiments, other colors associated with other wavelengths of light, including magenta and cyan, may be used in addition to or in place of one or more of the red, green, or blue colors.

[0067] It should be understood that references throughout this disclosure to a given color of light are understood to encompass light of one or more wavelengths within the range of wavelengths of light that are perceived by a viewer as that given color. For example, red light may include one or more wavelengths of light that are within the range of about 620-780 nm, green light may include one or more wavelengths of light that are within the range of about 492-577 nm, and blue light may include one or more wavelengths of light that are within the range of about 435-493 nm.

[0068] In some embodiments, the light source 530 (FIG. 6) may be configured to emit light at one or more wavelengths outside the range of visual perception of a viewer, e.g., infrared and / or ultraviolet wavelengths. Additionally, the waveguide in-coupling, out-coupling, and other light redirecting structures of the display 250 may be configured to direct and emit this light from the display to the user's eye 210, e.g., for imaging and / or user stimulation applications.

[0069] 9A, in some embodiments, light impinging on a waveguide may need to be redirected to in-couple the light into the waveguide. An in-coupling optical element may be used to redirect and in-couple the light into its corresponding waveguide. FIG. 9A illustrates a cross-sectional side view of an example of a plurality or set 660 of stacked waveguides, each including an in-coupling optical element. Each of the waveguides may be configured to output light of one or more different wavelengths or one or more different wavelength ranges. The stack 660 may correspond to the stack 260 (FIG. 6), and the illustrated waveguides of the stack 660 may correspond to a portion of the plurality of waveguides 270, 280, 290, 300, 310, although it should be understood that light from one or more of the image input devices 360, 370, 380, 390, 400 is launched into the waveguide from a position that requires the light to be redirected for in-coupling.

[0070] The illustrated stacked waveguide set 660 includes waveguides 670, 680, and 690. Each waveguide includes an associated incoupling optical element (which may also be referred to as the light input area on the waveguide), for example, incoupling optical element 700 is disposed on a major surface (e.g., the top major surface) of waveguide 670, incoupling optical element 710 is disposed on a major surface (e.g., the top major surface) of waveguide 680, and incoupling optical element 720 is disposed on a major surface (e.g., the top major surface) of waveguide 690. In some embodiments, one or more of the incoupling optical elements 700, 710, 720 may be disposed on a bottom major surface of the respective waveguide 670, 680, 690 (particularly when one or more of the incoupling optical elements are reflective polarizing optical elements). As shown, the incoupling optical elements 700, 710, 720 may be disposed on the upper major surfaces of their respective waveguides 670, 680, 690 (or on top of the next lower waveguide), and in particular, the incoupling optical elements are transmissive deflecting optical elements. In some embodiments, the incoupling optical elements 700, 710, 720 may be disposed within the body of the respective waveguides 670, 680, 690. In some embodiments, as discussed herein, the incoupling optical elements 700, 710, 720 are wavelength selective such that they selectively redirect one or more wavelengths of light while transmitting other wavelengths of light. Although illustrated on one side or corner of their respective waveguides 670, 680, 690, it should be understood that the incoupling optical elements 700, 710, 720 may be disposed within other areas of their respective waveguides 670, 680, 690 in some embodiments.

[0071] As shown, the in-coupling optical elements 700, 710, 720 may be laterally offset from one another. In some embodiments, each in-coupling optical element may be offset to receive light without that light passing through another in-coupling optical element. For example, each in-coupling optical element 700, 710, 720 may be configured to receive light from different image input devices 360, 370, 380, 390, and 400, as shown in FIG. 6, and may be separated (e.g., laterally spaced) from the other in-coupling optical elements 700, 710, 720 so as to not substantially receive light from others of the in-coupling optical elements 700, 710, 720.

[0072] Each waveguide also includes an associated light distribution element, for example, light distribution element 730 is disposed on a major surface (e.g., a top major surface) of waveguide 670, light distribution element 740 is disposed on a major surface (e.g., a top major surface) of waveguide 680, and light distribution element 750 is disposed on a major surface (e.g., a top major surface) of waveguide 690. In some other embodiments, light distribution elements 730, 740, 750 may be disposed on the bottom major surfaces of the associated waveguides 670, 680, 690, respectively. In some other embodiments, the light distribution elements 730, 740, 750 may be disposed on both the top and bottom major surfaces of the associated waveguides 670, 680, 690, respectively, or the light distribution elements 730, 740, 750 may be disposed on different ones of the top and bottom major surfaces in different associated waveguides 670, 680, 690, respectively.

[0073] The waveguides 670, 680, 690 may be spaced apart and separated, for example, by gas, liquid and / or solid layers of material. For example, as shown, layer 760a may separate waveguides 670 and 680, and layer 760b may separate waveguides 680 and 690. In some embodiments, layers 760a and 760b are formed from a low index material (i.e., a material having a lower index of refraction than the material forming the immediately adjacent ones of the waveguides 670, 680, 690). Preferably, the index of refraction of the material forming layers 760a, 760b is 0.05 or greater, or 0.10 or less, than the index of refraction of the material forming the waveguides 670, 680, 690. Advantageously, the lower refractive index layers 760a, 760b may act as cladding layers to promote total internal reflection (TIR) ​​of light through the waveguides 670, 680, 690 (e.g., TIR between the top and bottom major surfaces of each waveguide). In some embodiments, the layers 760a, 760b are formed from air. Although not shown, it should be understood that the top and bottom of the illustrated set of waveguides 660 may include immediate cladding layers.

[0074] Preferably, for ease of manufacturing and other considerations, the materials forming the waveguides 670, 680, 690 are similar or identical, and the materials forming the layers 760a, 760b are similar or identical. In some embodiments, the materials forming the waveguides 670, 680, 690 may vary between one or more of the waveguides, and / or the materials forming the layers 760a, 760b may differ while still maintaining the various refractive index relationships discussed above.

[0075] 9A, light rays 770, 780, 790 are incident on the set of waveguides 660. It should be understood that light rays 770, 780, 790 may be injected into the waveguides 670, 680, 690 by one or more image injection devices 360, 370, 380, 390, 400 (FIG. 6).

[0076] In some embodiments, the light beams 770, 780, 790 have different properties, e.g., different wavelengths or different wavelength ranges, that may correspond to different colors. Each of the incoupling optical elements 700, 710, 720 deflects the incident light such that the light propagates through a respective one of the waveguides 670, 680, 690 by TIR. In some embodiments, each of the incoupling optical elements 700, 710, 720 selectively deflects one or more particular wavelengths of light while transmitting other wavelengths to the underlying waveguide and associated incoupling optical element.

[0077] For example, incoupling optical element 700 may be configured to selectively deflect light beam 770 having a first wavelength or wavelength range while transmitting light beams 780 and 790 having different second and third wavelengths or wavelength ranges. The transmitted light beam 780 impinges on and is deflected by incoupling optical element 710, which is configured to selectively deflect light of the second wavelength or wavelength range. Light beam 790 is deflected by incoupling optical element 720, which is configured to selectively deflect light of the third wavelength or wavelength range.

[0078] 9A, the deflected light rays 770, 780, 790 are deflected to propagate through the corresponding waveguides 670, 680, 690. That is, the incoupling optical elements 700, 710, 720 of each waveguide deflect the light into its corresponding waveguide 670, 680, 690 and incoupling the light into the corresponding waveguide. The light rays 770, 780, 790 are deflected at an angle that causes the light to propagate through the respective waveguides 670, 680, 690 by TIR. The light rays 770, 780, 790 propagate through the respective waveguides 670, 680, 690 by TIR until they impinge on the corresponding light distribution elements 730, 740, 750 of the waveguides.

[0079]

[0046] Referring now to Figure 9B, a perspective view of the example of multiple stacked waveguides of Figure 9A is illustrated. As previously described, the in-coupled light rays 770, 780, 790 are deflected by the in-coupling optical elements 700, 710, 720, respectively, and then propagate by TIR within the waveguides 670, 680, 690, respectively. The light rays 770, 780, 790 then impinge on the light distribution elements 730, 740, 750, respectively. The light distribution elements 730, 740, 750 deflect the light rays 770, 780, 790 to propagate towards the out-coupling optical elements 800, 810, 820, respectively.

[0080] In some embodiments, the light distribution elements 730, 740, 750 are orthogonal pupil expanders (OPEs). In some embodiments, the OPEs deflect or distribute the light to the out-coupling optical elements 800, 810, 820, and in some embodiments, may increase the beam or spot size of the light as it propagates to the out-coupling optical elements. In some embodiments, the light distribution elements 730, 740, 750 may be omitted and the in-coupling optical elements 700, 710, 720 may be configured to deflect the light directly to the out-coupling optical elements 800, 810, 820. For example, referring to FIG. 9A, the light distribution elements 730, 740, 750 may be replaced with the out-coupling optical elements 800, 810, 820, respectively. In some embodiments, the outcoupling optical elements 800, 810, 820 are exit pupils (EPs) or exit pupil expanders (EPEs) that direct light towards the viewer's eye 210 (FIG. 7). It should be understood that the OPEs may be configured to increase the size of the eyebox in at least one axis, and the EPEs may increase the eyebox in an axis that intersects, e.g., is perpendicular to, the axis of the OPE. For example, each OPE may be configured to redirect a portion of the light that strikes it to an EPE in the same waveguide, while allowing the remaining portion of the light to continue propagating down the waveguide. Upon striking the OPE again, another portion of the remaining light is redirected to the EPE, which continues to propagate further down the waveguide, etc. Similarly, upon striking the EPE, a portion of the impinging light is redirected out of the waveguide towards the user, which continues to propagate through the waveguide until it strikes the EP again, at which point another portion of the impinging light is redirected out of the waveguide, etc. As a result, a single beam of internally coupled light may be "replicated" each time a portion of that light is redirected by an OPE or EPE, thereby forming a cloned beam field of light, as shown in Figure 6. In some embodiments, the OPE and / or EPE may be configured to modify the size of the beam of light.

[0081] Thus, referring to Figures 9A and 9B, in some embodiments, a set of waveguides 660 includes, for each primary color, a waveguide 670, 680, 690, an in-coupling optical element 700, 710, 720, a light distribution element (e.g., OPE) 730, 740, 750, and an out-coupling optical element (e.g., EP) 800, 810, 820. The waveguides 670, 680, 690 may be stacked with an air gap / cladding layer between each waveguide. The in-coupling optical element 700, 710, 720 redirects or deflects the incoming light into its waveguide (with different in-coupling optical elements receiving different wavelengths of light). The light then propagates at an angle that will result in TIR within the respective waveguide 670, 680, 690. In the example shown, light ray 770 (e.g., blue light) is polarized by the first in-coupling optical element 700 in the manner described above, then continues bouncing back down the waveguide, interacting with the light distribution element (e.g., OPE) 730 and then the out-coupling optical element (e.g., EP) 800. Light rays 780 and 790 (e.g., green and red light, respectively) pass through the waveguide 670, with light ray 780 incident on the in-coupling optical element 710 and being deflected thereby. Light ray 780 will then bounce back down the waveguide 680, via TIR, to its light distribution element (e.g., OPE) 740 and then the out-coupling optical element (e.g., EP) 810. Finally, light ray 790 (e.g., red light) passes through the waveguide 690 and impinges on the light in-coupling optical element 720 of the waveguide 690. The light in-coupling optical element 720 deflects the light beam 790 so that it propagates by TIR to the light distribution element (e.g., OPE) 750 and then to the out-coupling optical element (e.g., EP) 820. The out-coupling optical element 820 then finally out-couples the light beam 790 to a viewer, who also receives the out-coupled light from the other waveguides 670, 680.

[0082] FIG. 9C illustrates a top-down plan view of the example of multiple stacked waveguides of FIGS. 9A and 9B. As shown, the waveguides 670, 680, 690 may be vertically aligned with each waveguide's associated light distribution element 730, 740, 750 and associated out-coupling optical elements 800, 810, 820. However, as discussed herein, the in-coupling optical elements 700, 710, 720 are not vertically aligned. Rather, the in-coupling optical elements are preferably non-overlapping (e.g., spaced apart laterally as seen in the top-down view). As discussed further herein, this non-overlapping spatial arrangement facilitates the injection of light from different sources into different waveguides on a one-to-one basis, thereby allowing a particular light source to be uniquely coupled to a particular waveguide. In some embodiments, arrangements including non-overlapping, spatially separated in-coupling optical elements may be referred to as shifted pupil systems, and the in-coupling optical elements in these arrangements may correspond to sub-pupils.

[0083] As described herein, a display system (e.g., an augmented reality display system, such as the display system 80 of FIG. 2), according to various embodiments, may adjust the depth at which a virtual object is to be presented. As described above, a virtual object to be presented at a first depth may be adjusted to correspond to a second depth at which a second virtual object is to be presented or at which a real object resides. It should be understood that the different depths may correspond to different depth planes at which the display system is configured to place the virtual object. In some embodiments, a user of the display system may thus switch between viewing a first virtual object and a second virtual or real object without having to change accommodation and / or perceiving that the two objects are on different depth planes. Adjusting the depth may include one or both of adjusting accommodation cues (e.g., adjusting wavefront divergence) and adjusting binocular cues (e.g., adjusting the view of each of the virtual objects being provided to each eye of the user).

[0084] The display system may determine that the user is switching focus between a virtual object and a real object based on determining the user's three-dimensional gaze point. For example, the display system may determine that the user is switching the gaze point between virtual objects that are presented at the determined gaze point. The gaze point may indicate the location of a point in space along (1) an x-axis (e.g., a lateral axis), (2) a y-axis (e.g., a vertical axis), and (3) a z-axis (e.g., the depth of the point, e.g., the depth from the user). In some embodiments, the display system may utilize a sensor, such as a camera (e.g., sensor 630 of FIG. 6 ), to monitor the user's eyes (e.g., the pupil and / or cornea of ​​each eye, etc.) and determine the line of sight of each eye. The line of sight of each eye may be understood to be a vector extending from the fovea through the lens of the eye. The display system may be configured to extrapolate where the vectors associated with the eyes intersect, and this intersection may be understood to be the gaze point of the eye. In other words, the gaze point may be a location in three-dimensional space where the user's eyes are approaching. In some embodiments, the display system may filter slight movements of the user's eyes (e.g., saccadic movements, micro-saccadic movements), for example, during high speed movements, and may update the gaze point when it determines that the eye is fixating on a location in three-dimensional space. For example, the display system may be configured to ignore eye movements that are fixating on a point for less than a threshold duration, and / or to ignore involuntary eye movements (e.g., blinks).

[0085] 10A, an example illustrates a representation of content viewed by a user (e.g., content contained within a display frustum representing the user's field of view 1004) presented by a display system (e.g., display system 80, FIG. 2). The representation includes the user's eye 1002, and the content includes a first virtual object 1006 (e.g., a book) and a second virtual object 1008 (e.g., a tree). As an example, the user is reading about a tree described in the first virtual object 1006 (e.g., a book or text representation may appear to be presented to the user), and as the user reads the first virtual object 1006, different representations of the tree may be presented. Additionally, the book 1006 may optionally be a real-world object (e.g., an actual book), and as the user reads the book 1006, the display system may present the user with different trees that correspond to the trees described in the book 1006. The first virtual object 1006 or first real-world object and the second virtual object 1008 will hereinafter be referred to as the first object and the second object, respectively.

[0086] As illustrated, the first object 1006 and the second object 1008 may be associated with different depth planes, which may be depth planes at which the display system is configured to present virtual content. In some embodiments, the perceived depth of the second object 1008 is adjusted based on the perceived depth of the first object 1006, or vice versa. As an example, if the user is determined to be gazing at the first object 1006, the virtual content may be presented at depth plane B. Alternatively, if the user is determined to be gazing at the second object 1008, the virtual content may be presented at depth plane C. As described above, the display system (e.g., a variable focus display system) may present all virtual content at the same depth plane for each frame presented to the user. For example, the display system may output all virtual content via the same waveguide (e.g., one of the waveguides 270, 280, 290, 300, 310, FIG. 6) for each frame. As will be described below with respect to FIG. 11, each depth plane may be associated with a range of depths from the user. The display system may thus determine the user's three-dimensional gaze point and select a depth plane based on the depth associated with the gaze point. For example, depth range 1009 is associated with depth plane C, whereby a virtual object presented at a depth included within depth range 1009 is presented in depth plane C when gazed upon by the user. Although FIG. 10A illustrates four exemplary depth planes (e.g., depth planes A-D), other numbers of depth planes may be utilized (e.g., 2, 3, or more than 3 depth planes).

[0087] 10A-10B illustrate the depth plane as having a planar boundary, it should be understood that the size and shape of the depth plane may differ from that shown. For example, the depth planes described herein may be curved.

[0088] Continuing with reference to the example scenario depicted in FIGS. 10A and 1010A, a user views a first object 1006. For example, the user may fixate their eye 1002 on the first object 1006. The display system may determine a gaze point of the eye 1002 and determine that the gaze point corresponds to a location of the first object 1006. After viewing the first object 1006, the user may then gaze at a second object 1008, as shown in representation 1010B. In this example, the display system may continue to present virtual content, e.g., the first object 1006, at a different depth plane associated with the second object 1008.

[0089] As described above, the first object 1006 may optionally be a real-world object. In this scenario, the display system may determine that the user is gazed at a location in three-dimensional space associated with depth plane B (e.g., corresponding to a real-world object that may be represented by the first object 1006 in this example). The display system may present virtual content as the second object 1008 in a depth plane associated with depth C (e.g., the second object 1008 may be presented in depth plane C).

[0090] If both objects are virtual objects, as the user alternates gaze between the first object 1006 and the second object 1004, the display system may typically be required to change the depth plane at which the virtual content is presented depending on whether the first object 1006 or the second object 1008 is being gazed upon. Similarly, the user's eye 1002 may be required to change accommodation as the content switches between depth plane B and depth plane C. As described herein, in some circumstances, switching between depth planes may undesirably cause flicker and / or momentary delays in perceiving the content as the user's accommodation response adjusts to the different depth planes.

[0091] Advantageously, in some embodiments, the display system may modify the depth plane in which the virtual object is presented, which may reduce the switching of the display system between depth planes and / or the switching of the user's accommodation response. FIG. 10B illustrates another example of a user's representation of viewing content. As shown, the second object 1008 is adjusted to be associated with the same depth plane as the first object 1006. For example, the first object 1006 and the second object 1008 are both associated with or located on depth plane B. In some embodiments, the wavefront divergence will be the same when light is output to the user to provide image information regarding either the first object 1006 or the second object 1008. Thus, the user's eye 1002 may avoid being required to change accommodation when switching focus between the virtual objects 1006, 1008.

[0092] While the depth plane associated with the second object 1008 is adjusted to correspond to the first object 1006, the display system may maintain (e.g., not adjust) the view of the second object 1008 presented to each eye 1002 of the user (e.g., perceived depth as determined from binocular separation presentation and stereoscopic vision). For example, as illustrated in FIG. 10A, the second object 1008 (e.g., a tree) is positioned further in depth than the first object 1006. The second object 1008 may be adjusted such that the wavefront divergence of the light representing the second object 1008 is modified (e.g., accommodation cues are adjusted). However, the second object 1008 may still be perceived via binocular disparity to be located further in depth from the first object 1006 (e.g., binocular cues may be maintained). As used herein, it should be understood that adjusting accommodation cues involves changing the wavefront divergence of light that provides image information for forming the user's view of a virtual object, and adjusting binocular cues involves changing the view of a virtual object presented to one or both eyes of the viewer. Adjusting accommodation cues while maintaining binocular cues may result in an accommodation-vergence mismatch, such that binocular disparity presents a first depth to the user, while wavefront divergence presents a second depth to the user. If this mismatch exceeds a threshold (e.g., 0.33 diopters or more, 0.5 diopters or more), a negative physiological response may be experienced by the user (e.g., headaches).

[0093] Optionally, the display system may determine that the mismatch exceeds a threshold and may further adjust binocular cues for the second object 1008 and / or the first object 1006. As an example, the view of the second object 1008 provided by the display system to each eye of the user may be adjusted (binocular cues may be adjusted) to correspond to a view of the second object 1008 that would appear to be at the same or similar depth from the depth plane B. That is, the second object 1008 will be perceived to be located at the same or similar depth from the user as the first object 1006. This may introduce perceptible modifications in the three-dimensional location of the second object 1008, but a reduction in negative physiological responses may be advantageous. Optionally, the perceived size of the second object 1008 may be adjusted according to the perceived distance the second object 1008 appears to have moved. For example, as illustrated in FIG. 10A, the second object 1008 was initially presented as being farther away from the first object 1006 (e.g., based at least in part on binocular disparity). Thus, if the binocular cues are adjusted such that the second object 1008 is perceived to be located closer to the user, the display system may scale the second virtual object 1008 so that they are perceived to be of a similar size. For example, the display system may scale the second virtual object 1008 to occupy the same amount (e.g., volume and / or area) of the user's field of view 1004. As another example, the display system may scale the second virtual object 1008 to match the angular resolution of the user's eyes. For example, the font size of the text may be increased for a book that is moved farther away from the user.

[0094] Optionally, the display system may determine that the mismatch exceeds a threshold and may adjust the binocular cues of the second object 1008 so that the mismatch is less than or equal to the threshold. That is, as opposed to modifying the binocular cues (e.g., the view of the object 1008 provided to each eye) to correspond to the same depth as the first virtual object 1006, the display system may modify the binocular cues so that the mismatch is simply less than the threshold. This may have the effect that the second object 1008 is perceived by the user to be closer in depth, but is suddenly not perceived to be at the same depth as the first object 1006.

[0095] The display system may optionally adjust the depth of the second object 1008 upon determining that the user is switching between the first object 1006 and the second object 1008 above a threshold metric, e.g., above a threshold number of times, with a frequency above a threshold frequency, and / or for a threshold duration. For example, if the user regularly gazes at the first object 1006 and infrequently or sporadically gazes at the second object 1008, the display system may decide not to adjust the depth plane associated with the second object 1008. On the other hand, by way of example, if the user gazes back and forth between the first object 1006 and the second object 1008 for the length of several seconds or minutes, the display system may place the first and second objects at a common depth.

[0096] The common depth may be selected based on various criteria. For example, if the first object 1006 is a real object (e.g., a book) and the second object 1008 is a virtual object, the display system may optionally adjust the depth plane associated with the second object 1008 (e.g., the adjusted depth plane may be depth plane B). In some embodiments, the first object 1006 and the second object 1008 may both be virtual objects, and a decision regarding the depth plane at which to place both objects may be made based on the depth plane the user is primarily fixating on. For example, the decision may be based on the amount of time the user fixates on each virtual object. For example, if the user spends a greater amount of time fixating the first object 1006, the display system may adjust the depth plane associated with the second object 1008 such that the second object is placed on depth plane B. In some embodiments, the display system may obtain information indicative of the user's preferences. For example, a user may indicate that the second object 1008 is considered to be the primary virtual object, and thus the depth plane associated with the first object 1006 may be adjusted so that it corresponds to the depth plane of the second object 1008. Optionally, certain types of virtual objects may be identified as not being available for depth adjustment. As an example, a virtual object containing text or fine detail may maintain its current depth plane, while other virtual objects are adjusted.

[0097] Optionally, in addition to adjusting the depth cue, the display system may adjust the location of the second virtual object 1008, for example, so that the second virtual object 1008 is shifted in location. In some embodiments, a user may indicate a location where the second virtual object 1008 should be located. For example, a user who is a surgeon may prefer that virtual content in the form of medical information be displayed in a particular location relative to the patient. The surgeon may indicate this particular location using input such as a hand gesture, voice input, a totem, etc. For example, the display system may recognize a hand gesture as indicating a particular location, and the display system may adjust the location of the second virtual object 1008 so that it is perceived to be in the particular location.

[0098] FIG. 11 illustrates a representation of a field of view 1100 of a user of a display system and further illustrates the adjustment of various depth planes. The field of view 1100 includes a representation of a first depth plane 1102 and a second depth plane 1104. As shown, a depth range (e.g., a volume associated with each depth plane) is illustrated corresponding to each depth plane. For example, the proximal range of depth plane 2 extends from depth 1106A to depth 1106B. A virtual object to be presented at a depth within the range 1106A-1106B may be presented in depth plane 2 (also identified as reference number 1104). By way of example, the virtual object may be output via a waveguide associated with depth plane 2. In addition, the wavefront divergence of any virtual object to be presented at a depth within the range 1106A-1106B may be identical and therefore associated with depth plane 2. As described above with respect to Figure 10A, the size and shape of the depth plane may differ from that illustrated in Figure 11. For example, the volume that defines the depth plane may have a curved shape.

[0099] As described above, the display system may determine the user's point of gaze. If the point of gaze is within range 1106A-1106B, the display system may present the virtual content with wavefront divergence associated with depth plane 2. If the user then gazes at a location that is within the range associated with depth plane 1, the display system presents the content with wavefront divergence associated with depth plane 1. As described above, the display system may be a variable focus display system such that a single depth plane is utilized for any frame being presented to the user. For example, one waveguide may be utilized to output all virtual content for each frame.

[0100] In some embodiments, as described herein, the display system may adjust the depth plane in which a particular virtual object is to be presented. In this way, the display system may limit the extent to which the selected depth plane needs to be modified to present the virtual content. As an example, a first object may be presented in depth plane 1 volume 1108 and a second object may be presented in depth plane 2 volume 1109. Without utilizing the techniques described herein, when a user gazes at a first object, the display system may present the first object and the second object on depth plane 2 1104 (e.g., via the same waveguide associated with depth plane 2 1104). Subsequently, when the user switches the gaze point to the second object, the display may present the first object and the second object via depth plane 1 1102. In contrast, in some embodiments, when a user changes the gaze point between the first object and the second object, both objects may be located on the same depth plane. That is, the depth plane associated with either the first object or the second object may be adjusted such that either depth plane 2 1104 or depth plane 1 1102 may be associated with both objects.

[0101] 12 illustrates a flowchart of an example process 1200 for adjusting a depth plane associated with a virtual object. For convenience, process 1200 is described as being performed by a display system (e.g., wearable display system 60), which may include processing hardware and software and may optionally provide information to one or more computers or other external processing systems, e.g., offload processing to the external systems, and receive information from the external systems.

[0102] In block 1202, the display system monitors the three-dimensional gaze point of the user's eye. As described above, the display system may include a sensor for monitoring information associated with the user's eye (e.g., eye orientation). A non-exhaustive list of sensors includes an infrared sensor, an ultraviolet sensor, and a visible wavelength light sensor. The sensor may optionally output infrared, ultraviolet, visible, and / or polarized light onto the user's eye and determine a reflection of the output light from the user's eye. By way of example, the infrared light may be output by an infrared light emitter and an infrared light sensor. It should be understood that the sensor, which may include a light emitter, may correspond to the imaging device 630 of FIG. 6.

[0103] The display system may utilize sensors to track the user's gaze by determining a line of sight associated with each eye (e.g., a vector extending from the user's eye as extending from the fovea through the eye's lens) and the intersection of the lines of sight of each eye. For example, the display system may output infrared light onto the user's eye and a reflection from the eye (e.g., a corneal reflection) may be monitored. A vector between the pupil center of the eye and the reflection from the eye (e.g., the display system may determine the pupil centroid, e.g., through infrared imaging) may be used to determine the line of sight of the eye. The intersection of the lines of sight may thus be assigned as a three-dimensional gaze point. Optionally, the display system may utilize orientation information associated with the display system (e.g., information describing the orientation of the display system in three-dimensional space) when determining the gaze point.

[0104] The display system may monitor the determined gaze point to track the object the user is viewing. For example, the display system may determine that the user is viewing a first virtual object based on the determined three-dimensional gaze point that corresponds to a three-dimensional location where the first virtual object is presented. In addition, the display system may determine that the user is viewing a location that does not correspond to the virtual object and determine that a real-world object is likely located at the gaze point.

[0105] At block 1204, the display system obtains location information associated with the virtual object for presentation to the user. Prior to rendering the virtual object for presentation to the user (e.g., via the output of the waveguide, as described above), the display system may obtain three-dimensional location information associated with the virtual object. For example, as described above, the virtual object may be presented to the user such that the content appears to be located in the real world (e.g., the content may be located at different depth planes within the user's field of view). It should be understood that the display system may include or have access to a three-dimensional map of the surrounding environment that includes the intended location of any virtual content within the surrounding environment. With reference to this map, the display system may access and provide information that defines the three-dimensional location of the virtual content within the user's field of view (e.g., the location within the display frustum, as illustrated in FIGS. 10A-10B).

[0106] As described above, location information for a virtual object may include a three-dimensional location. Based on the three-dimensional location, the virtual object may be associated with a particular depth plane such that when a user gazes at the virtual object, the particular depth plane may be utilized to present all virtual content for each frame until the user switches gaze (e.g., as shown and described in FIG. 11 ).

[0107] In block 1206, the display system adjusts the depth plane associated with the virtual object. As described above with respect to FIGS. 10A-10B, the display system may determine that the user is switching between two or more fixation points more than a threshold metric, e.g., more than a threshold number of times or more frequently than a threshold frequency. For example, the user may switch between a first fixation point and a second fixation point once every 30 seconds, minute, minutes, etc. If the first fixation point and the second fixation point are associated with different depth planes, e.g., as illustrated in FIG. 11, and the fixation points are located within different depth plane volumes, the display system may be required to present content for the different depth planes each time the user switches between fixation points (e.g., without utilizing the techniques described herein).

[0108] The display system may therefore adjust a depth plane associated with the virtual object. As described herein, this may include associating the virtual object with the depth plane of another object (e.g., virtual object, real-world object) that the user is also gazing at. That is, accommodation cues (e.g., wavefront divergence) associated with the virtual object may be adjusted to correspond to a different depth plane. The display system may utilize the resulting location information to determine a three-dimensional location of the virtual object and may update the location information with the adjusted depth plane. As described above, the display system may select and adjust the virtual object according to how often the virtual object is gazed at. For example, if the user gazes at a first virtual object more than a second virtual object, the display system may adjust the second virtual object to be presented on the depth plane where the first virtual object is already presented.

[0109] Additionally, in some embodiments, the display system may obtain an indication of a virtual object that should be adjusted. As an example, a user may indicate that a particular virtual object should be given a preference for a given adjustment so that other virtual objects are adjusted and the particular virtual object remains in its associated depth plane. As another example, a moving virtual object (e.g., moving faster than a threshold rate) may be a given preference, for example, to reduce distraction caused by non-gaze objects. Optionally, the display system may obtain an indication of a virtual object that should not be adjusted. Furthermore, the display system may optionally obtain an indication of a virtual object that is linked to the user and remains in focus so that they are presented in the same depth plane even when adjustments are made. For example, the display system may present five virtual objects and ensure that two of the five virtual objects remain in focus (e.g., the two virtual objects may be presented in the same depth plane).

[0110] In block 1208, the display system presents the adjusted content to the user. For example, the adjusted virtual object may be output to the user with an adjusted wavefront divergence. That is, when the user gazes at the virtual object, the virtual object may be output to the user with a wavefront divergence corresponding to the adjusted depth plane rather than its original depth plane (as indicated by the display system's map of the surrounding environment). An example of adjusting wavefront divergence is adjusting the particular waveguide in which the virtual object is to be displayed, where different waveguides output light with different amounts of wavefront divergence.

[0111] 13 illustrates a flowchart of another example process 1300 for adjusting a depth plane associated with a virtual object. For convenience, process 1300 may be described as being performed by a display system (e.g., wearable display system 60), which may include processing hardware and software, and may optionally provide information to one or more computers or other external processing systems, e.g., offload processing to the external systems, and receive information from the external systems.

[0112] In block 1302, the display system monitors a three-dimensional gaze point, and in block 1304, the display system obtains location information associated with the content to be presented (similar to blocks 1202, 1204 (FIG. 12), respectively). In block 1306, the display system adjusts a depth plane associated with the virtual object. As described above with respect to FIG. 12 (e.g., block 1206), the display system may associate a different depth plane with the virtual object, thereby adjusting accommodation cues associated with the virtual object. In contrast, in block 1306, the display system may adjust binocular cues to adjust the perceived depth of the virtual object. That is, the display system may adjust the view of the virtual object provided to each eye of the user, and such adjustments may involve adjusting the binocular disparity of the virtual content through binocular separation presentation. In this manner, the virtual object may appear to be presented at the same or similar depth as other virtual content or at a depth different from the original depth of the virtual object. The display system then presents the adjusted content to the user in block 1308 as described above for block 1208 with respect to FIG.

[0113] 14 illustrates a flowchart of an example process for adjusting accommodation and binocular cues associated with a virtual object. For convenience, process 1300 may be described as being performed by a display system (e.g., wearable display system 60), which may include processing hardware and software, and may optionally provide information to one or more computers or other external systems for processing, e.g., offload processing to the external systems, and receive information from the external systems.

[0114] In block 1402, the display system obtains an indication of a virtual object to be adjusted, as described above with respect to blocks 1202, 1204 (FIG. 12). As described above, the presentation of a particular virtual object or one or more virtual objects may be adjusted with respect to an associated depth plane.

[0115] At block 1404, accommodation cues associated with the virtual object are adjusted. As described herein, a depth plane associated with the virtual object may be adjusted relative to a depth plane indicated by a map of the display system. In some embodiments, the wavefront divergence of the virtual object may be adjusted to be the same as one or more other virtual objects that the user is also gazing at. Because adjusting the depth plane adjusts the wavefront divergence, by utilizing binocular disparity, the virtual object may be perceived by the user to be in the same unadjusted three-dimensional location. For example, the display system may present to each eye of the user the same view of the virtual object as would be presented without adjusting the wavefront divergence of the virtual object, e.g., by maintaining the same binocular separation presentation. Thus, even if the wavefront divergence of the output light is adjusted, the user will perceive the virtual object in the same three-dimensional location in space (e.g., due to binocular disparity). As described above, adjusting the wavefront divergence rather than the binocular cues (e.g., the view of the virtual object provided to the user) may introduce a perceptible mismatch to the user.

[0116] Advantageously, in some embodiments, the display system adjusts the binocular cues associated with the virtual object in block 1406 so that they match the changes in the accommodation cues. To reduce the mismatch between vergence and accommodation, for example, the display system may adjust the view of the virtual object presented to each eye of the user. For example, if the accommodation cues associated with the virtual object are adjusted so that the depth is perceived to be closer to the user, the display system may similarly adjust the binocular cues to correspond to that closer depth. As described above with respect to FIGS. 10A-10B, the display system may implement the adjustment of the binocular cues after determining that the user is switching between two or more fixation points above a threshold metric, e.g., above a threshold number of times or above a threshold frequency.

[0117] At block 1408, the adjusted virtual content is presented to the user. Because both accommodation and binocular cues have been adjusted, the virtual content will be perceived to be located at a new location in three-dimensional space corresponding to the updated depth. Optionally, because the virtual content will be perceived at the new location, the display system may update location information associated with the virtual content to correspond to the new location.

[0118] It should be understood that each of the processes, methods, and algorithms described herein and / or depicted in the figures may be embodied in code modules executed by one or more physical computing systems, hardware computer processors, application-specific circuits, and / or electronic hardware configured to execute specific and particular computer instructions, and thus may be fully or partially automated. For example, a computing system may include a general-purpose computer (e.g., a server) or a special-purpose computer programmed with specific computer instructions, special-purpose circuits, etc. The code modules may be compiled and linked into an executable program, installed in a dynamic link library, or written in an interpreted programming language. In some implementations, certain operations and methods may be performed by circuitry specific to a given function.

[0119] Furthermore, certain implementations of the functionality of the present disclosure may be sufficiently mathematically, computationally, or technically complex that special purpose hardware (utilizing appropriate specialized executable instructions) or one or more physical computing devices may be required to implement the functionality, e.g., due to the amount or complexity of the calculations involved, or to provide results in substantially real-time. For example, a video may contain many frames, each frame may have millions of pixels, and specifically programmed computer hardware may be required to process the video data to provide the desired image processing task or application in a commercially reasonable amount of time.

[0120] The code modules or any type of data may be stored on any type of non-transitory computer readable medium, such as physical computer storage devices, including hard drives, solid state memory, random access memory (RAM), read only memory (ROM), optical disks, volatile or non-volatile storage devices, combinations of the same, and / or the like. In some embodiments, the non-transitory computer readable medium may be part of one or more of the local processing and data module (140), the remote processing module (150), and the remote data repository (160). The methods and modules (or data) may also be transmitted (e.g., as part of a carrier wave or other analog or digital propagating signal) generated on a variety of computer readable transmission media, including wireless-based and wired / cable-based media, and may take a variety of forms (e.g., as part of a single or multiplexed analog signal, or as multiple individual digital packets or frames). The results of the disclosed processes or process steps may be stored persistently or otherwise in any type of non-transitory tangible computer storage device or communicated via a computer readable transmission medium.

[0121] Any process, block, state, step, or functionality in the flow diagrams described herein and / or depicted in the accompanying figures should be understood as potentially representing a code module, segment, or portion of code that includes one or more executable instructions for implementing a specific function (e.g., logical or arithmetic) or step in the process. The various processes, blocks, states, steps, or functionality may be combined, rearranged, added, deleted, modified, or otherwise altered from the illustrative examples provided herein. In some embodiments, additional or different computing systems or code modules may perform some or all of the functionality described herein. The methods and processes described herein are not limited to any particular sequence, and the blocks, steps, or states associated therewith may also be performed in other sequences as appropriate, e.g., serially, in parallel, or in some other manner. Tasks or events may be added to or removed from the disclosed exemplary embodiments. Furthermore, the separation of various system components in the implementations described herein is for illustrative purposes and should not be understood as requiring such separation in all embodiments. It should be understood that the program components, methods, and systems described may generally be integrated together in a single computer product or packaged into multiple computer products.

[0122] In the foregoing specification, the invention has been described with reference to specific embodiments thereof. It will, however, be apparent that various modifications and changes can be made therein without departing from the broader spirit and scope of the invention. The specification and drawings are, therefore, to be regarded in an illustrative rather than a restrictive sense.

[0123] Indeed, it should be understood that each of the systems and methods of the present disclosure has several innovative aspects, none of which is solely responsible for or required for the desirable attributes disclosed herein. The various features and processes described above may be used independently of one another or may be combined in various ways. All possible combinations and subcombinations are intended to fall within the scope of the present disclosure.

[0124] Certain features described herein in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, although features may be described above as acting in a combination and may even be initially claimed as such, one or more features from the claimed combination may in some cases be deleted from the combination, and the claimed combination may be subject to subcombinations or variations of the subcombination. No single feature or group of features is necessary or essential to every embodiment.

[0125] In particular, it should be understood that conditional statements used herein, such as "can," "could," "might," "may," "eg," and the like, are generally intended to convey that certain embodiments include certain features, elements, and / or steps while other embodiments do not, unless specifically stated otherwise or understood otherwise within the context as used. Thus, such conditional statements are generally not intended to suggest that features, elements, and / or steps are in any way required for one or more embodiments, or that one or more embodiments necessarily include logic for determining whether those features, elements, and / or steps should be included or performed in any particular embodiment, with or without authorial input or prompting. The terms "comprising," "including," "having," and the like, are synonymous and used inclusively in a non-limiting manner and do not exclude additional elements, features, acts, operations, etc. Also, the term "or" is used in its inclusive sense (and not its exclusive sense), thus, for example, when used to connect a list of elements, the term "or" means one, some, or all of the elements in the list. In addition, the articles "a," "an," and "the," as used in this application and the appended claims, should be interpreted to mean "one or more" or "at least one," unless otherwise specified. Similarly, although operations may be depicted in the figures in a particular order, it should be recognized that such operations need not be performed in the particular order depicted, or in the sequential order, or that all of the depicted operations need not be performed to achieve desirable results. Furthermore, the figures may diagrammatically depict one or more exemplary processes in the form of a flow chart. However, other operations not depicted may also be incorporated within the diagrammatically depicted exemplary methods and processes. For example, one or more additional operations may be performed before, after, simultaneously with, or during any of the depicted operations. In addition, operations may be rearranged or reordered in other implementations.In some situations, multitasking and parallel processing may be advantageous. Furthermore, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments, and it should be understood that the program components and systems described may generally be integrated together in a single software product or packaged into multiple software products. Additionally, other implementations are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results.

[0126] Thus, the claims are not intended to be limited to the implementations shown in the specification but are to be accorded the widest scope consistent with the disclosure, the principles and novel features disclosed herein.

Claims

[Claim 1] A system, method, etc. as depicted in the drawings.

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