Eyepiece architecture incorporating artifact reduction

Abstract

To provide an eyepiece architecture appropriately incorporating artifact mitigation.SOLUTION: Techniques for artifact mitigation in an optical system are disclosed. Light associated with a world object is received at the optical system, which is characterized by a world side and a user side. Light associated with a virtual image is projected onto an eyepiece of the optical system, causing a portion of the light associated with the virtual image to propagate toward the user side and light associated with an artifact image to propagate toward the world side. A dimmer of the optical system positioned between the world side and the eyepiece is adjusted to reduce an intensity of the light associated with the artifact image impinging on the dimmer and an intensity of the light associated with the world object impinging on the dimmer.SELECTED DRAWING: Figure 4C

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of priority to U.S. Provisional Patent Application No. 62 / 784,013, filed December 21, 2018, and entitled “EYEPIECE ARCHITECTURE INCORPORATING ARTIFACT MITIGATION,” the contents of which are incorporated herein in their entirety. [Background technology]

[0002] 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. 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.

[0003] Despite the advances made in these display technologies, there remains a need in the art for improved methods, systems, and devices relating to augmented reality systems, and particularly display systems. Summary of the Invention [Means for solving the problem]

[0004] The present disclosure generally relates to techniques for improving the performance and user experience of optical systems. More specifically, embodiments of the present disclosure provide methods for operating an augmented reality (AR) device that includes various adaptive lens assemblies, dynamic dimmers, and / or eyepieces. Although the present invention is described with reference to an AR device, the present disclosure is applicable to various applications in computer vision and image display systems.

[0005] According to a first aspect of the disclosure, a method of operating an optical system is provided. The method may include receiving light associated with a world object at the optical system, the optical system being characterized by a world side and a user side opposite the world side. In some embodiments, the light associated with the world object is received from the world side. The method may also include projecting light associated with a first virtual image onto an eyepiece of a first optical system for one or more first time intervals, propagating a portion of the light associated with the first virtual image toward the user side and propagating light associated with a first artifact image toward the world side, and adjusting a first dimmer of the optical system positioned between the world side and the first eyepiece to reduce an intensity of light associated with the first artifact image impinging on the first dimmer and an intensity of light associated with the world object impinging on the first dimmer.

[0006] In some embodiments, the method further includes projecting light associated with the second virtual image onto a second eyepiece of the optical system positioned between the world side and the first dimmer for one or more second time intervals, propagating a portion of the light associated with the second virtual image toward the user side and propagating light associated with the second artifact image toward the world side, and adjusting the first dimmer to allow light associated with the second virtual image that impinges on the first dimmer to pass substantially through the first dimmer. In some embodiments, the method further includes adjusting a second dimmer of the optical system positioned between the world side and the second eyepiece for one or more first time intervals to allow light associated with a world object impinging on the second dimmer to pass substantially through the second dimmer, and adjusting the second dimmer for one or more second time intervals to reduce an intensity of light associated with a second artifact image impinging on the second dimmer and an intensity of light associated with a world object impinging on the second dimmer.

[0007] In some embodiments, the one or more first time intervals at least partially overlap with the one or more second time intervals. In some embodiments, the one or more first time intervals are not simultaneous with the one or more second time intervals. In some embodiments, the method further includes adjusting the first dimmer during one or more third time intervals to allow light associated with the world object impinging on the first dimmer to pass substantially through the first dimmer, and adjusting the second dimmer to allow light associated with the world object impinging on the second dimmer to pass substantially through the second dimmer. In some embodiments, the one or more third time intervals are not simultaneous with both the one or more first time intervals and the one or more second time intervals. In some embodiments, the method further includes receiving a brightness value of the light associated with the world object from an ambient light sensor, and determining a duration or frequency of the one or more first time intervals based on the brightness value.

[0008] According to a second aspect of the disclosure, an optical system is provided that is configured to receive light associated with a world object. The optical system may include a first eyepiece. The optical system may also include a projector configured to project light associated with a first virtual image onto the first eyepiece during one or more first time intervals, propagate a portion of the light associated with the first virtual image toward a user side, and propagate light associated with a first artifact image toward a world side. In some embodiments, the optical system is characterized by a world side and a user side opposite the world side. In some embodiments, the light associated with the world object is received from the world side. The optical system may further include a first dimmer positioned between the world side and the first eyepiece. In some embodiments, the first dimmer is configured to be adjusted to reduce an intensity of light associated with the first artifact image impinging on the first dimmer and an intensity of light associated with the world object impinging on the first dimmer.

[0009] In some embodiments, the optical system further includes a second eyepiece positioned between the world side and the first dimmer. In some embodiments, the projector is configured to project light associated with the second virtual image onto the second eyepiece during one or more second time intervals, propagating the light associated with the second virtual image toward the user side and propagating the light associated with the second artifact image toward the world side. In some embodiments, the first dimmer is configured to allow light associated with the second virtual image that impinges on the first dimmer during one or more second time intervals to pass substantially through the first dimmer. In some embodiments, the optical system further includes a second dimmer positioned between the world side and the second eyepiece. In some embodiments, the second dimmer is configured to be adjusted to allow light associated with a world object that impinges on the second dimmer during one or more first time intervals to pass substantially through the second dimmer. In some embodiments, the second dimmer is configured to reduce an intensity of light associated with a second artifact image impinging on the second dimmer and an intensity of light associated with a world object impinging on the second dimmer for one or more second time intervals.

[0010] In some embodiments, the one or more first time intervals at least partially overlap with the one or more second time intervals. In some embodiments, the one or more first time intervals are not simultaneous with the one or more second time intervals. In some embodiments, the first dimmer is configured to be adjusted to allow light associated with a world object impinging on the first dimmer to pass substantially through the first dimmer during the one or more third time intervals, and the second dimmer is configured to be adjusted to allow light associated with a world object impinging on the second dimmer to pass substantially through the second dimmer during the one or more third time intervals. In some embodiments, the one or more third time intervals are not simultaneous with both the one or more first time intervals and the one or more second time intervals. In some embodiments, the optical system further includes an ambient light sensor configured to detect a brightness value of the light associated with the world object. In some embodiments, a duration or frequency of the one or more first time intervals is based on the brightness value.

[0011] According to a third aspect of the present disclosure, a non-transitory computer-readable medium is provided, which may include instructions that, when executed by a processor, cause the processor to perform operations, including the methods described in relation to the first aspect of the present disclosure.

[0012] Numerous advantages are achieved by the methods of the present disclosure over conventional techniques. For example, the embodiments described herein reduce the amount of artifactual image light reaching the user's eye while still efficiently projecting the desired image light out of the eyepiece and to the user, which has been a significant limitation in optical systems. Other approaches to reducing artifactual image light using anti-reflective coatings have been ineffective. The embodiments further utilize dynamic dimmers, which have other uses such as reducing the amount of world light reaching the user's eye in bright outdoor conditions. Some embodiments allow for significant reductions in artifactual image light while having only minimal or minor impact on world light and only minimal or minor impact on the desired image light. Other advantages of the present disclosure will be readily apparent to those skilled in the art. The present specification also provides, for example, the following items: (Item 1) 1. A method of operating an optical system, the method comprising: receiving light associated with a world object at the optical system, the optical system being characterized by a world side and a user side opposite the world side, the light associated with the world object being received from the world side; During one or more first time intervals, projecting light associated with a first virtual image onto a first eyepiece of the optical system, propagating a portion of the light associated with the first virtual image towards the user side and propagating light associated with a first artifact image towards the world side; adjusting a first dimmer of the optical system positioned between the world side and the first eyepiece to reduce an intensity of light associated with the first artifact image impinging on the first dimmer and an intensity of light associated with the world object impinging on the first dimmer; A method comprising: (Item 2) During one or more second time intervals. projecting light associated with a second virtual image onto a second eyepiece of the optical system positioned between the world side and the first dimmer, propagating a portion of the light associated with the second virtual image towards the user side and propagating light associated with a second artifact image towards the world side; adjusting the first dimmer to allow light associated with the second virtual image impinging on the first dimmer to pass substantially through the first dimmer; The method of claim 1, further comprising: (Item 3) During the one or more first time intervals, adjusting a second dimmer of the optical system positioned between the world side and the second eyepiece to allow light associated with the world object impinging on the second dimmer to pass substantially through the second dimmer; During the one or more second time intervals. adjusting the second dimmer to reduce an intensity of light associated with the second artifact image impinging on the second dimmer and an intensity of light associated with the world object impinging on the second dimmer; The method according to item 2, further comprising: (Item 4) 4. The method of claim 3, wherein the one or more first time intervals at least partially overlap with the one or more second time intervals. (Item 5) 4. The method of claim 3, wherein the one or more first time intervals are not simultaneous with the one or more second time intervals. (Item 6) During one or more third time intervals, adjusting the first dimmer to allow light associated with the world object impinging on the first dimmer to pass substantially through the first dimmer; adjusting the second dimmer to allow light associated with the world object impinging on the second dimmer to pass substantially through the second dimmer; The method of claim 3, further comprising: (Item 7) 7. The method of claim 6, wherein the one or more third time intervals are not simultaneous with both the one or more first time intervals and the one or more second time intervals. (Item 8) receiving, from an ambient light sensor, a light intensity value associated with the world object; determining a duration or a frequency of the one or more first time intervals based on the brightness values; The method of claim 1, further comprising: (Item 9) 1. An optical system configured to receive light associated with a world object, the optical system comprising: A first eyepiece; a projector configured to project light associated with a first virtual image onto the first eyepiece during one or more first time intervals, propagating a portion of the light associated with the first virtual image towards a user side and propagating light associated with a first artifact image towards a world side, the optical system being characterized by the world side and the user side facing the world side, and light associated with the world object being received from the world side; a first dimmer positioned between the world side and the first eyepiece, the first dimmer configured to be adjusted to reduce an intensity of light associated with the first artifact image impinging on the first dimmer and an intensity of light associated with the world object impinging on the first dimmer; An optical system comprising: (Item 10) a second eyepiece positioned between the world side and the first dimmer, the projector configured to project light associated with a second virtual image onto the second eyepiece during one or more second time intervals, propagating the light associated with the second virtual image towards the user side and propagating light associated with a second artifact image towards the world side; Further equipped with 10. The optical system of claim 9, wherein the first dimmer is configured to allow light associated with the second virtual image impinging on the first dimmer during the one or more second time intervals to pass substantially through the first dimmer. (Item 11) a second dimmer positioned between the world side and the second eyepiece, the second dimmer configured to be adjusted to allow light associated with the world object impinging on the second dimmer to pass substantially through the second dimmer during the one or more first time intervals. Further equipped with 11. The optical system of claim 10, wherein the second dimmer is configured to reduce an intensity of light associated with the second artifact image impinging on the second dimmer and an intensity of light associated with the world object impinging on the second dimmer during the one or more second time intervals. (Item 12) Item 12. The optical system of item 11, wherein the one or more first time intervals at least partially overlap with the one or more second time intervals. (Item 13) Item 12. The optical system of item 11, wherein the one or more first time intervals are not simultaneous with the one or more second time intervals. (Item 14) the first dimmer is configured to be adjusted to allow light associated with the world object impinging on the first dimmer to pass substantially through the first dimmer during one or more third time intervals; the second dimmer is configured to be adjusted to allow light associated with the world object impinging on the second dimmer to pass substantially through the second dimmer during the one or more third time intervals. Item 12. The optical system according to item 11. (Item 15) 15. The optical system of claim 14, wherein the one or more third time intervals are not simultaneous with both the one or more first time intervals and the one or more second time intervals. (Item 16) an ambient light sensor configured to detect a brightness value of a light associated with the world object, wherein a duration or a frequency of the one or more first time intervals is based on the brightness value; 10. The optical system of item 9, further comprising: (Item 17) A non-transitory computer readable medium comprising instructions that, when executed by a processor, cause the processor to: receiving light associated with a world object at an optical system; During one or more first time intervals, projecting light associated with a first virtual image onto a first eyepiece of the optical system, propagating a portion of the light associated with the first virtual image towards a user side and propagating light associated with a first artifact image towards a world side; adjusting a first dimmer of the optical system positioned between the world side and the first eyepiece to reduce an intensity of light associated with the first artifact image impinging on the first dimmer and an intensity of light associated with the world object impinging on the first dimmer; A non-transitory computer readable medium for performing operations including: (Item 18) The operation further comprises: During one or more second time intervals. projecting light associated with a second virtual image onto a second eyepiece of the optical system positioned between the world side and the first dimmer, propagating a portion of the light associated with the second virtual image towards the user side and propagating light associated with a second artifact image towards the world side; adjusting the first dimmer to allow light associated with the second virtual image impinging on the first dimmer to pass substantially through the first dimmer; 20. The non-transitory computer-readable medium of item 17, comprising: (Item 19) The operation further comprises: During the one or more first time intervals, adjusting a second dimmer of the optical system positioned between the world side and the second eyepiece to allow world light impinging on the second dimmer to pass substantially through the second dimmer; During the one or more second time intervals. adjusting the second dimmer to reduce an intensity of light associated with the second artifact image impinging on the second dimmer and an intensity of the world light impinging on the second dimmer; 20. The non-transitory computer-readable medium of item 18, comprising: (Item 20) 20. The non-transitory computer-readable medium of claim 19, wherein the one or more first time intervals at least partially overlap with the one or more second time intervals. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 illustrates an augmented reality (AR) scene as viewed through a wearable AR.

[0014] [Figure 2A] FIG. 2A illustrates an AR device operating under a first operating condition without artifactual image light.

[0015] [Figure 2B] FIG. 2B illustrates the AR device operating under a second operating condition with artifact image light.

[0016] [Figure 2C] 2C and 2D illustrate an AR device that includes a first dimmer and a second dimmer. [Figure 2D] 2C and 2D illustrate an AR device that includes a first dimmer and a second dimmer.

[0017] [Diagram 3] FIG. 3 illustrates a schematic diagram of a wearable AR device.

[0018] [Figure 4A] FIG. 4A illustrates an AR device operating under a first operating condition without artifactual image light.

[0019] [Figure 4B] FIG. 4B illustrates the AR device operating under a second operating condition with artifact image light.

[0020] [Figure 4C]FIG. 4C illustrates an AR device that includes a dimmer.

[0021] [Figure 4D] FIG. 4D illustrates an AR device that includes a dimmer.

[0022] [Figure 5A] FIG. 5A illustrates an AR device that includes a dimmer.

[0023] [Figure 5B] FIG. 5B illustrates an AR device that includes a dimmer.

[0024] [Figure 5C] FIG. 5C illustrates an AR device that includes a dimmer.

[0025] [Figure 6A] FIG. 6A illustrates a timing diagram for an AR device.

[0026] [Figure 6B] FIG. 6B illustrates a timing diagram for an AR device.

[0027] [Figure 6C] FIG. 6C illustrates a timing diagram for an AR device.

[0028] [Figure 6D] FIG. 6D illustrates a timing diagram for an AR device.

[0029] [Figure 7A] FIG. 7A illustrates a timing diagram for an AR device.

[0030] [Figure 7B] FIG. 7B illustrates a timing diagram for an AR device.

[0031] [Figure 7C]FIG. 7C illustrates a timing diagram for an AR device.

[0032] [Figure 8] FIG. 8 illustrates a method of operating the optical system.

[0033] [Figure 9] FIG. 9 illustrates a simplified computer system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] Optical see-through (OST) augmented reality (AR) devices can refine the virtual content being presented to a user by applying a refractive power to the virtual image light (e.g., light associated with a virtual image) using one or more adaptive lens assemblies arranged in an optical stack. As the optical stack and eyepiece become more and more complex with additional layers, especially those with high refractive index, persistence of image reflections (alternatively referred to herein as artifact images) caused by a portion of the virtual image light propagating toward the world side of the AR device and reflecting back toward the user becomes a serious problem. In some instances, the exit pupil expander (EPE) and orthogonal pupil expander (OPE) regions of the eyepiece can cause undesirable reflections toward the world side, causing image light to launch toward the world side as well as toward the user. The use of anti-reflective coatings can work for simple designs, however, these coatings can be ineffective when a refractive power is applied to the projected light. The problem is further exacerbated due to curved or tilted (eg, due to assembly tolerances) surfaces within the optical stack.

[0035] The embodiments of the present disclosure address these and other issues by providing one or more dynamic dimmers positioned within the optical stack to dim artifact image light (e.g., light originating from undesired reflections of projected light) passing therethrough. The dimmers may be time-synchronized with the projector to dim only when a certain waveguide receives / propagates light. In some embodiments, a single dynamic dimmer is positioned between two eyepieces corresponding to different depth planes. In some embodiments, two dynamic dimmers may be employed, each positioned on the world side of one of the two eyepieces.

[0036] FIG. 1 illustrates an AR scene 100 as viewed through a wearable AR device, according to some embodiments. The AR scene 100 is depicted such that a user of the AR technology sees a real-world park-like setting 106 featuring people, trees, buildings in the background, and a real-world concrete platform 120. In addition to these items, the user of the AR technology also perceives that they "see" a robotic figure 110 standing on the real-world concrete platform 120 and a flying cartoon-like avatar character 102 that appears to be an anthropomorphic bumblebee, although these elements (the character 102 and the figure 110) do not exist in the real world. Due to the significant complexity of the human visual perception and nervous system, it is difficult to produce virtual reality (VR) or AR technology that facilitates the presentation of virtual image elements among other virtual or real-world image elements that is comfortable, natural-feeling, and rich.

[0037] 2A illustrates an AR device 200 operating under a first operating condition without artifact image light, according to some embodiments. During operation, the projector 214 of the AR device 200 may project virtual image light 223 (e.g., light associated with virtual content) onto the first eyepiece 202-1 and / or the second eyepiece 202-2, which may project a light field (e.g., an angular representation of the virtual content) onto the user's retina such that the user perceives the corresponding virtual content as being located at a location within the user's environment. For example, the virtual image light 223 coupled out by the first eyepiece 202-1 may occur such that the user may perceive the character 102 as being located at the first virtual depth plane 210-1, and the virtual image light 223 coupled out by the second eyepiece 202-2 may occur such that the user may perceive the image 110 as being located at the second virtual depth plane 210-2. The user perceives the virtual content along with world lights 232, which correspond to one or more world objects 230, such as the platform 120.

[0038] In some embodiments, the AR device 200 may include a first adaptive lens assembly 205-1 positioned on a user-side of the first eyepiece 202-1 (the side of the first eyepiece 202-1 closest to the user's eye), a second adaptive lens assembly 205-2 positioned on a world-side of the first eyepiece 202-1 and on a user-side of the second eyepiece 202-2 (e.g., between the eyepieces 202-1, 202-2), and a third adaptive lens assembly 205-3 positioned on the world-side of the second eyepiece 202-2. Each of the lens assemblies 205-1, 205-2, 205-3 may be configured to apply a refractive power to light passing therethrough. In some embodiments, the third lens assembly 205-3 is configured to apply an opposite refractive power to the world light 232 passing therethrough as compared to the lens assemblies 205-1, 205-2 so as to prevent distortion caused by the refractive power applied by the lens assemblies 205-1, 205-2.

[0039] 2B illustrates the AR device 200 operating under a second operating condition in which the artifact image light 212 is first emitted from the eyepieces 202-1, 202-2 toward the world side and reflected toward the user side, causing the artifact image light 212 to be projected onto the user's retina such that the user perceives the corresponding virtual content as being located at a location in the user's environment. For example, the artifact image light 212 emitted from the first eyepiece 202-1 toward the world side may cause the user to perceive the first artifact image 216-1 as being located at or near the first virtual depth plane 210-1, and the artifact image light 212 emitted from the second eyepiece 202-2 may cause the user to perceive the second artifact image 216-2 as being located at or near the second virtual depth plane 210-2. In some embodiments, the first artifact image 216-1 may be positioned near the second virtual depth plane 210-2 and / or the second artifact image 216-2 may be positioned near the first virtual depth plane 210-1. The first artifact image 216-1 may be similar in appearance to the character 102 and the second artifact image 216-2 may be similar in appearance to the figure 110. In addition to the light emitted toward the world and reflecting back to the user, the light emitted toward the user may be reflected twice and returned to the user as artifact image light. This may be caused by two reflections and therefore may be less noticeable than the light emitted toward the world side and reflected back toward the user, since it is likely much stronger than any two or more reflected artifact light, including a single reflection. In some instances, the eyepiece may emit the same or approximately the same amount of light toward the world side as toward the user side. In some embodiments, additional artifact images may be perceived by a user depending on the number of different possible reflections of the virtual image light 223 within the optical stack.

[0040] 2C and 2D illustrate an AR device 200 including a first dimmer 203-1 and a second dimmer 203-2 according to some embodiments. The first dimmer 203-1 may be positioned on the world side of the first eyepiece 202-1 and on the user side of the second lens assembly 205-2 (e.g., between the first eyepiece 202-1 and the second lens assembly 205-2), and the second dimmer 203-2 may be positioned on the world side of the second eyepiece 202-2 and on the user side of the third lens assembly 205-3 (e.g., between the second eyepiece 202-2 and the third lens assembly 205-3). Referring to FIG. 2C, during a first time interval, the projector 214 may project a virtual image light 223 onto the first eyepiece 202-1. Also, during the first time interval, the first dimmer 203-1 may be adjusted to reduce the light passing therethrough, which may include reducing the intensity of artifact image light 212 propagating from the first eyepiece 202-1 toward the world side and / or the intensity of world light 232 propagating toward the user side and impinging on the first dimmer 203-1.

[0041] 2D, during the second time interval, the projector 214 may project the virtual image light 223 onto the second eyepiece 202-2. Also, during the second time interval, the second dimmer 203-2 may be adjusted to reduce the light passing therethrough, which may include reducing the intensity of the artifact image light 212 propagating from the second eyepiece 202-2 toward the world side and / or the intensity of the world light 232 propagating toward the user side and impinging on the second dimmer 203-2. In some embodiments, the second dimmer 203-2 may also reduce the artifact image light 212 propagating from the first eyepiece 202-1 when both the second dimmer 203-2 and the first eyepiece 202-1 are activated. As used herein, a dimmer element may be considered to be "activated" when dimmer functionality is implemented, e.g., the intensity of light passing therethrough is reduced. As used herein, an eyepiece may be considered to be "activated" when virtual image light 223 is projected onto the eyepiece, e.g., onto any one or more of the eyepiece's waveguides.

[0042] In some embodiments, the AR device 200 may cycle between operation during a first time interval and operation during a second time interval such that the eyepieces 202-1, 202-2 are activated at different times. For example, the AR device 200 may cycle between operation during a first time interval and operation during a second time interval at a frequency of 10 Hz, 100 Hz, 1 kHz, or any frequency in between. Thus, one or more first time intervals may partially overlap (e.g., in parallel), completely overlap (e.g., simultaneously), or completely non-overlapping (e.g., non-concurrent) with one or more second time intervals. The AR device 200 may dynamically adjust the duration of the first and second time intervals based on several factors, including, but not limited to, the brightness of the virtual content, the brightness of the virtual image light 223, the brightness of the world light 232, the user-defined brightness for the virtual content, the user-defined brightness for the world light 232, the software-defined brightness for the virtual content, and the software-defined brightness for the world light 232, among other possibilities. In addition, each depth plane can remain indefinitely and / or independently. The AR device 200 may change between depth planes / eyepieces depending on the depth content to be displayed and / or where the user is looking as determined, for example, by an eye tracking system.

[0043] As used herein, one or more first time intervals are considered non-concurrent with one or more second time intervals when none of the time intervals of the one or more first time intervals overlaps with any of the time intervals of the one or more second time intervals. According to one embodiment, one or more first time intervals including the following time intervals: 0 ms-10 ms, 20 ms-30 ms, 40 ms-50 ms, 60 ms-70 ms, and 80 ms-90 ms are considered non-concurrent with one or more second time intervals including the following time intervals: 10 ms-20 ms, 30 ms-40 ms, 50 ms-60 ms, 70 ms-80 ms, and 90 ms-100 ms. According to another embodiment, one or more first time intervals including the following time intervals: 0 ms-10 ms, 40 ms-50 ms, and 80 ms-90 ms are considered non-concurrent with one or more second time intervals including the following time intervals: 20 ms-30 ms and 60 ms-70 ms.

[0044] In some embodiments, the AR device 200 may include an ambient light sensor 234 configured to detect the world light 232. The ambient light sensor 234 may be positioned such that the world light 232 detected by the ambient light sensor 234 resembles and / or represents the world light 232 impinging on the AR device 200. In some embodiments, the ambient light sensor 234 may be configured to detect one or more spatially resolved light values ​​corresponding to different pixels of a camera of the AR device 200. In some embodiments, the ambient light sensor 234 may be configured to detect a global light value corresponding to an average light intensity or a single light intensity of the world light 232. The detected ambient light may be used by the AR device 200 to determine a time-averaged transmission state of the first and second dimmers 203-1, 203-2. For example, the detected ambient light may be used to determine a switching frequency and / or an amount of transmission of the first and second dimmers 203-1, 203-2 during the first and second time intervals.

[0045] 3 illustrates a schematic diagram of a wearable AR device 300 according to some embodiments. The AR device 300 may include a left eyepiece 302A, a left dimmer 303A, and a left lens assembly 305A arranged in a side-by-side configuration, and a right eyepiece 302B, a right dimmer 303B, and a right lens assembly 305B also arranged in a side-by-side configuration. In some embodiments, the AR device 300 includes one or more sensors, including, but not limited to, a left front facing world camera 306A mounted directly on or near the left eyepiece 302A, a right front facing world camera 306B mounted directly on or near the right eyepiece 302B, a left side facing world camera 306C mounted directly on or near the left eyepiece 302A, a right side facing world camera 306D mounted directly on or near the right eyepiece 302B, a left eye tracker positioned to observe the user's left eye, a right eye tracker positioned to observe the user's right eye, and an ambient light sensor 334. In some embodiments, the AR device 300 includes one or more image projection devices, such as a left projector 314A optically linked to the left eyepiece 302A, and a right projector 314B optically linked to the right eyepiece 302B.

[0046] Some or all of the components of the AR device 300 may be head-mounted such that the projected image may be viewed by the user. In some embodiments, all of the components of the AR device 300 shown in FIG. 3 are mounted on a single device (e.g., a single headset) that is wearable by the user. In some embodiments, one or more components of the processing module 350 are physically separate from the other components of the AR device 300 and communicatively coupled thereto by one or more wired and / or wireless connections. For example, the processing module 350 may include a local module 352 on the head-mounted portion of the AR device 300 and a remote module 356 that is physically separate from and communicatively linked to the local module 352. The remote module 356 may be mounted in various configurations, such as fixedly attached to a frame, fixedly attached to a helmet or hat worn by the user, built into headphones, or otherwise removably attached to the user (e.g., in a backpack configuration, in a belt-coupled configuration, etc.).

[0047] The processing module 350 may include a processor and associated digital memory, such as non-volatile memory (e.g., flash memory), both of which may be utilized to aid in processing, caching, and storing data. The data may include data captured from sensors that may be operatively coupled to the AR device 300 or otherwise attached to the user, such as, for example, the camera 306, the ambient light sensor 334, an eye tracker, a microphone, an inertial measurement unit, an accelerometer, a compass, a GPS unit, a wireless device, and / or a gyroscope. For example, the processing module 350 may receive the image 320 from the camera 306. Specifically, the processing module 350 may receive a left front image 320A from a left front facing world camera 306A, a right front image 320B from a right front facing world camera 306B, a left side image 320C from a left side facing world camera 306C, and a right side image 320D from a right side facing world camera 306D. In some embodiments, the images 320 may include a single image, a pair of images, a video including a stream of images, a video including a stream of paired images, and the like. The images 320 may be generated and sent to the processing module 350 periodically while the AR device 300 is powered on, or may be generated in response to an instruction sent by the processing module 350 to one or more of the cameras 306. In some embodiments, the processing module 350 may receive ambient light information from the ambient light sensor 334. In some embodiments, the processing module 350 may receive gaze information from an eye tracker. In some embodiments, the processing module 350 may receive image information (e.g., image brightness values) from one or both of the projectors 314.

[0048] The eyepieces 302A, 302B may each include a transparent or semi-transparent waveguide configured to direct and out-couple light from the projectors 314A, 314B. Specifically, the processing module 350 may cause the left projector 314A to output left virtual image light 322A onto the left eyepiece 302A, and the right projector 314B to output right virtual image light 322B onto the right eyepiece 302B. In some embodiments, the eyepieces 302 may each include one or more waveguides corresponding to different colors and / or different depth planes. In some embodiments, the dimmer 303 may be coupled to and / or integrated with the eyepieces 302. For example, the dimmer 303 may be incorporated into a multi-layer eyepiece and may form one or more layers that make up one of the eyepieces 302. In some embodiments, the processing module 350 may electrically activate the dimmers 303A, 303B using a left dimmer control signal 319A and a right dimmer control signal 319B, respectively.

[0049] The cameras 306A, 306B may be positioned to capture images that substantially overlap the field of view of the user's left and right eyes, respectively. Thus, the placement of the cameras 306 may be near the user's eyes, but not so close as to obscure the user's field of view. Alternatively or in addition, the cameras 306A, 306B may be positioned to align with the internal coupling locations of the virtual image lights 322A, 322B, respectively. The cameras 306C, 306D may be positioned to capture images, for example, to the sides of the user, within the user's peripheral vision or outside the user's peripheral vision. The images 320C, 320D captured using the cameras 306C, 306D do not necessarily overlap with the images 320A, 320B captured using the cameras 306A, 306B.

[0050] 4A illustrates an AR device 200 operating under a first operating condition without artifact image light, according to some embodiments. FIG. 4A may correspond to the same scenario illustrated in FIG. 2A. During operation, the projector 214 projects virtual image light 223 onto one or more waveguides of the first eyepiece 202-1 and / or one or more waveguides of the second eyepiece 202-2, which may project a light field onto the user's retina such that the user perceives the corresponding virtual content as being located at a location within the user's environment. The user perceives the virtual content along with world light 232, which corresponds to one or more world objects 230. In some embodiments, the AR device 200 may include a first adaptive lens assembly 205-1 positioned on the user side of the first eyepiece 202-1, a second adaptive lens assembly 205-2 positioned on the world side of the first eyepiece 202-1 and on the user side of the second eyepiece 202-2, and a third adaptive lens assembly 205-3 positioned on the world side of the second eyepiece 202-2.

[0051] 4B illustrates the AR device 200 operating under a second operating condition in which light is initially emitted from the first eyepiece 202-1 toward the world and user side, and the world side light is reflected toward the user side, causing artifact image light 212 to be projected onto the user's retina such that the user perceives one or more artifact images 216 as being located at a location within the user's environment. In the illustrated embodiment, virtual image light 223 is projected onto a waveguide (e.g., a second waveguide) of the first eyepiece 202-1, causing light to be emitted from the second waveguide of the first eyepiece 202-1 toward the world and user side. The artifact image light 212 then reflects toward the user side from various surfaces on the world side of the second waveguide of the first eyepiece 202-1, including the third waveguide of the first eyepiece 202-1, the second lens assembly 205-2, each of the waveguides of the second eyepiece 202-2, and the third lens assembly 205-3. Each reflection may cause the user to perceive an additional artifact image 216.

[0052] In some embodiments, the user may perceive an additional artifact image 216 based on more than one or two reflections (e.g., three or more reflections). For example, the user may perceive an artifact image 216 based on light emitted from the second waveguide of the first eyepiece 202-1 toward the world side, reflected from the third waveguide of the first eyepiece 202-1 toward the user side, reflected from the first lens assembly 205-1 toward the world side, and reflected from the first waveguide of the first eyepiece 202-1 toward the user side. Such images are typically weaker (e.g., in terms of brightness, contrast, etc.) and present fewer problems compared to artifact images 216 based on single or double reflected light. Even high quality AR coatings may be insufficient to mitigate the artifact image light because many surfaces from which reflections occur may make the artifact image light stronger. Additionally, if the assembly includes optical power elements, such as lens assemblies 205-1, 205-2, 205-3, these may spatially concentrate the artifact image light making it more noticeable to the user.

[0053] 4C illustrates an AR device 200 including dimmers 203-1, 203-2, according to some embodiments. In the illustrated embodiment, the first dimmer 203-1 is positioned on the world side of the first eyepiece 202-1 and the user side of the second lens assembly 205-2, and the second dimmer 203-2 is positioned on the world side of the second eyepiece 202-2 and the user side of the third lens assembly 205-3. During the first time interval, the projector 214 may project the virtual image light 223 onto the second waveguide of the first eyepiece 202-1. Also, during the first time interval, the first dimmer 203-1 is adjusted, for example, to partially, but not completely, dim the artifact image light 212 passing therethrough, and a second time to cause some of the artifact image light 212 to propagate toward the world side, reflect off various surfaces on the world side of the first dimmer 203-1, and continue to pass through the first dimmer 203-1. Because the first dimmer 203-1 is adjusted to only partially dim the light passing therethrough, some of the world light 232 impinging on the first dimmer 203-1 can pass through the first dimmer 203-1 and reach the user's eye. Such an embodiment can be effective to significantly reduce the artifact image light 212 reaching the user's eye, while at the same time allowing some of the world light 232 to reach the user's eye. In some embodiments, the undesired artifact image light 212 must pass through the first dimmer 203-1 twice, which doubles the losses incurred by the artifact image light 212. The first dimmer 203-1 may be a single, spatially uniform dimming of light, or it may be a spatially varying transmission.

[0054] 4D illustrates an AR device 200 including dimmers 203-1, 203-2, according to some embodiments. During the second time interval, the projector 214 may project the virtual image light 223 onto a waveguide (e.g., a second waveguide) of the second eyepiece 202-2. Also during the second time interval, the second dimmer 203-2 is adjusted to, for example, partially, but not completely, dim the artifact image light 212 passing therethrough, a second time to cause some of the artifact image light 212 to propagate toward the world side, reflect off various surfaces on the world side of the second dimmer 203-2, and continue to pass through the second dimmer 203-2. Because the second dimmer 203-2 is adjusted to only partially dim the light passing through it, some of the world light 232 impinging on the second dimmer 203-2 is able to pass through the second dimmer 203-2 and reach the user's eye. Such an embodiment may be effective to significantly reduce the artifact image light 212 reaching the user's eye while at the same time allowing some of the world light 232 to reach the user's eye. In some embodiments, the undesirable artifact image light 212 must pass through the second dimmer 203-2 twice, which doubles the loss that the artifact image light 212 incurs. The second dimmer 203-2 may be a single spatially uniform dimming of light or may be a spatially varying transmission.

[0055] FIG. 5A illustrates an AR device 200 including dimmers 203-1, 203-2, according to some embodiments. During a first time interval, the projector 214 may project the virtual image light 223 onto a waveguide (e.g., a second waveguide) of the first eyepiece 202-1. Also, during the first time interval, the first dimmer 203-1 is adjusted to completely or substantially dim the artifact image light 212 passing therethrough, causing the artifact image light 212 impinging on the first dimmer 203-1 to be blocked. Because the first dimmer 203-1 is adjusted to completely or substantially dim the artifact image light 212 passing therethrough, the world light 232 impinging on the first dimmer 203-1 may be blocked and prevented from reaching the user's eye.

[0056] FIG. 5B illustrates an AR device 200 including dimmers 203-1, 203-2, according to some embodiments. During the second time interval, the projector 214 may project the virtual image light 223 onto a waveguide (e.g., a second waveguide) of the second eyepiece 202-2. Also, during the second time interval, the second dimmer 203-2 is adjusted to completely or substantially dim the artifact image light 212 passing therethrough and block the artifact image light 212 impinging on the second dimmer 203-2. Because the second dimmer 203-2 is adjusted to completely or substantially dim the artifact image light 212 passing therethrough, the world light 232 impinging on the second dimmer 203-2 may be blocked and prevented from reaching the user's eye.

[0057] 5C illustrates an AR device 200 including dimmers 203-1, 203-2, according to some embodiments. During the third time interval, the projector 214 may be turned off or configured not to project onto either of the eyepieces 202-1, 202-2. Also during the third time interval, the first dimmer 203-1 is adjusted to allow world light 232 impinging on the first dimmer 203-1 to pass completely or substantially through the first dimmer 203-1, e.g., the first dimmer 203-1 is turned off. Also, during the third time interval, the second dimmer 203-2 is adjusted to allow the world light 232 impinging on the second dimmer 203-2 to pass completely or substantially through the second dimmer 203-2, e.g., the second dimmer 203-2 is turned off. In some embodiments, the sequence of the time intervals may be, for example, a first time interval, a second time interval, and a third time interval. This sequence may then be repeated. In some embodiments, the sequence of the time intervals may be, for example, a first time interval, a third time interval, a second time interval, and a third time interval. This sequence may then be repeated. In some embodiments, any one of the time intervals may be repeated consecutively. Those skilled in the art will appreciate that the time intervals may occur in any manner desired.

[0058] 6A illustrates a timing diagram for controlling an optical device such as the AR device 200, according to some embodiments. In the illustrated embodiment, the AR device 200 cycles between operation during a first time interval in which the first eyepiece 202-1 is activated, the second eyepiece 202-2 is not activated, the first dimmer 203-1 is turned on, and the second dimmer 203-2 is turned off, and operation during a second time interval in which the first eyepiece 202-1 is not activated, the second eyepiece 202-2 is activated, the first dimmer 203-1 is turned off, and the second dimmer 203-2 is turned on. In the illustrated embodiment, the first and second time intervals are non-simultaneous. When turned on, the first dimmer 203-1 and the second dimmer 203-2 are both adjusted to reduce the light passing therethrough, for example, by 50%. Thus, the world light 232 is reduced by 50% on average while the AR device 200 operates according to the timing diagram shown. Those skilled in the art will understand that the first dimmer 203-1 and the second dimmer 203-2 may be adjusted to reduce the light passing therethrough by different percentages based on the desired system output (e.g., the amount of artifactual image light to be mitigated, the amount of artifactual world light to be mitigated, the like).

[0059] 6B illustrates a timing diagram for controlling an optical device such as the AR device 200, according to some embodiments. In the illustrated embodiment, the AR device 200 cycles between operation during a first time interval in which the first eyepiece 202-1 is activated, the second eyepiece 202-2 is not activated, the first dimmer 203-1 is turned on, and the second dimmer 203-2 is turned off, and operation during a second time interval in which the first eyepiece 202-1 is not activated, the second eyepiece 202-2 is activated, the first dimmer 203-1 is turned off, and the second dimmer 203-2 is turned on. In the illustrated embodiment, the first and second time intervals are non-simultaneous. When turned on, the first dimmer 203-1 is adjusted to reduce the light passing therethrough by 75%, and the second dimmer 203-2 is adjusted to reduce the light passing therethrough by 25%. Thus, the world light 232 is reduced by 50% on average while the AR device 200 operates according to the timing diagram shown. Those skilled in the art will understand that the first dimmer 203-1 and the second dimmer 203-2 may be adjusted to reduce the light passing therethrough by different percentages based on the desired system output (e.g., the amount of artifactual image light to be mitigated, the amount of artifactual world light to be mitigated, the like).

[0060] 6C illustrates a timing diagram for controlling an optical device such as the AR device 200, according to some embodiments. In the illustrated embodiment, the AR device 200 cycles between operation during a first time interval in which the first eyepiece 202-1 is activated, the second eyepiece 202-2 is not activated, the first dimmer 203-1 is turned on, and the second dimmer 203-2 is turned on, and operation during a second time interval in which the first eyepiece 202-1 is not activated, the second eyepiece 202-2 is activated, the first dimmer 203-1 is turned off, and the second dimmer 203-2 is turned on. When turned on, the first dimmer 203-1 is adjusted to reduce the light passing therethrough by 66.7%, and the second dimmer 203-2 is adjusted to reduce the light passing therethrough by 25%. Thus, the world light 232 is reduced by 50% on average while the AR device 200 operates according to the illustrated timing diagram.

[0061] 6D illustrates a timing diagram for controlling an optical device such as the AR device 200, according to some embodiments. In the illustrated embodiment, the AR device 200 cycles between operation during a first time interval in which the first eyepiece 202-1 is activated, the second eyepiece 202-2 is not activated, the first dimmer 203-1 is turned on, and the second dimmer 203-2 is turned on, and operation during a second time interval in which the first eyepiece 202-1 is not activated, the second eyepiece 202-2 is activated, the first dimmer 203-1 is turned off, and the second dimmer 203-2 is turned on. When turned on, the first dimmer 203-1 is adjusted to reduce the light passing therethrough by 29.3%, and the second dimmer 203-2 is adjusted to reduce the light passing therethrough by either 29.3% (during the first time interval) or 50% (during the second time interval). Thus, the world light 232 is reduced by 50% on average while the AR device 200 operates according to the illustrated timing diagram. As demonstrated by Figures 6A-6D, the AR device 200 is capable of achieving a similar world light dimming factor while varying the dimming levels of the dimmers 203-1, 203-2. Those skilled in the art will understand that first dimmer 203-1 and second dimmer 203-2 may be adjusted to reduce the light passing therethrough by different percentages based on the desired system output (e.g., the amount of artifactual image light to be mitigated, the amount of artifactual world light to be mitigated, or the like).

[0062] 7A illustrates a timing diagram for controlling an optical device such as the AR device 200, according to some embodiments. In the illustrated embodiment, the AR device 200 includes ... The eyepiece 202-1 is activated, the first dimmer 203-1 is turned off, and the second dimmer 203-2 is turned on, and a third time interval during which the eyepiece 202-1 is not activated, the second eyepiece 202-2 is not activated, the first dimmer 203-1 is turned off, and the second dimmer 203-2 is turned off. In the illustrated embodiment, the first time interval, the second time interval, and the third time interval are non-concurrent. When turned on, the first dimmer 203-1 is adjusted to completely or substantially block light passing therethrough, and the second dimmer 203-2 is adjusted to completely or substantially block light passing therethrough. When the first time interval, the second time interval, and the third time interval have equal durations (e.g., D1=D2=D3), the world light 232 is reduced by 66.7% on average while the AR device 200 operates according to the illustrated timing diagram. Those skilled in the art will understand that the first time interval, the second time interval, and the third time interval may differ (e.g., be unequal) from those shown in the illustrated embodiment.

[0063] 7B illustrates a timing diagram for controlling an optical device such as the AR device 200, according to some embodiments. In the illustrated embodiment, the AR device 200 includes ... The eyepiece 202-1 is activated, the first dimmer 203-1 is turned off, and the second dimmer 203-2 is turned on, and a third time interval during which the eyepiece 202-1 is not activated, the second eyepiece 202-2 is not activated, the first dimmer 203-1 is turned off, and the second dimmer 203-2 is turned off. In the illustrated embodiment, the first time interval, the second time interval, and the third time interval are non-concurrent. When turned on, the first dimmer 203-1 is adjusted to completely or substantially block light passing therethrough, and the second dimmer 203-2 is adjusted to completely or substantially block light passing therethrough. When the third time interval has twice the duration of the first and second time intervals (e.g., D3=2D1=2D2), the world light 232 is reduced by 50% on average while the AR device 200 operates according to the illustrated timing diagram. Those skilled in the art will understand that the first, second, and third time intervals may differ from those shown in the illustrated embodiment (e.g., the third time interval may be more or less than twice the duration of the first and second time intervals).

[0064] 7C illustrates a timing diagram for controlling an optical device such as the AR device 200, according to some embodiments. In the illustrated embodiment, the AR device 200 includes ... The eyepiece 202-1 cycles between operation during a third time interval during which the first dimmer 203-1 is turned off and the second dimmer 203-2 is turned off, operation during a second time interval during which the first ocular 202-1 is not activated, the second ocular 202-2 is activated, the first dimmer 203-1 is turned off and the second dimmer 203-2 is turned on, and again operation during a third time interval. In the illustrated embodiment, the first, second and third time intervals are non-simultaneous. When turned on, the first dimmer 203-1 is adjusted to completely or substantially block light passing therethrough and the second dimmer 203-2 is adjusted to completely or substantially block light passing therethrough. When the third time interval has twice the duration of the first and second time intervals (e.g., D3=2D1=2D2), the world light 232 is reduced by 50% on average while the AR device 200 operates according to the illustrated timing diagram. Those skilled in the art will understand that the first, second, and third time intervals may differ from those shown in the illustrated embodiment.

[0065] 8 illustrates a method 800 of operating an optical system, such as the AR device 200, according to some embodiments. One or more steps of the method 800 may be performed in a different order than in the illustrated embodiment, and one or more steps of the method 800 may be omitted during implementation of the method 800. One or more steps of the method 800 may be implemented, caused, or initiated by one or more components of the AR device 200, 300. For example, one or more steps of the method 800 may be initiated by the processing module 350, which may send a control signal (e.g., the dimmer control signal 319) to the dimmer 303 and / or the projector 314.

[0066] In step 802, world light 232 is received at an optical system. The optical system may be characterized by a world side and a user side opposite the world side. The world light 232 may be received from the world side of the optical system such that a source of the world light 232 is closest to the world side of the optical system and such that the world light 232 may reach the world side of the optical system prior to reaching the user side of the optical system.

[0067] During the first time interval, one or more of steps 804, 806, and 808 may be performed. In step 804, the virtual image light 223 is projected onto the first eyepiece 202-1 (e.g., onto one or more waveguides of the first eyepiece 202-1). In some embodiments, projecting the virtual image light 223 onto the first eyepiece 202-1 causes a portion of the virtual image light 223 to propagate toward the user side and another portion of the virtual image light 223 (referred to as artifact image light 212) to propagate toward the world side, as illustrated in FIGS. 2B, 4B, 4C, and 5A.

[0068] In step 806, the first dimmer 203-1 is adjusted to reduce the intensity of the artifact image light 212 impinging on the first dimmer 203-1 and / or the intensity of the world light 232 impinging on the first dimmer 203-1, as illustrated in Figures 4C and 5A. In step 808, the second dimmer 203-2 is adjusted to allow the light impinging on the second dimmer 203-2 (e.g., world light 232) to pass substantially through the second dimmer 203-2, as illustrated in Figure 4C. After the first time interval, the method 800 may proceed to a second time interval or a third time interval.

[0069] During the second time interval, one or more of steps 810, 812, and 814 may be performed. In step 810, the virtual image light 223 is projected onto the second eyepiece 202-2 (e.g., onto one or more waveguides of the second eyepiece 202-2). In some embodiments, projecting the virtual image light 223 onto the second eyepiece 202-2 causes a portion of the virtual image light 223 to propagate toward the user side and another portion of the virtual image light 223 (referred to as artifact image light 212) to propagate toward the world side, as illustrated in FIGS. 2B, 4D, and 5B.

[0070] In step 812, the second dimmer 203-2 is adjusted to reduce the intensity of the artifact image light 212 impinging on the second dimmer 203-2 and / or the intensity of the world light 232 impinging on the second dimmer 203-2, as illustrated in Figures 4D and 5B. In step 814, the first dimmer 203-1 is adjusted to allow the virtual image light 223 impinging on the first dimmer 203-1 and / or the world light 232 to pass substantially through the first dimmer 203-1, as illustrated in Figure 4D. After the second time interval, the method 800 may proceed to the first time interval or the third time interval.

[0071] During the third time interval, one or more of steps 816 and 818 are performed. In step 816, the first dimmer 203-1 is adjusted to allow the world light 232 impinging on the first dimmer 203-1 to pass substantially through the first dimmer 203-1, as illustrated in FIG. 5C. In step 818, the second dimmer 203-2 is adjusted to allow the world light 232 impinging on the second dimmer 203-2 to pass substantially through the second dimmer 203-2, as illustrated in FIG. 5C. Additionally, during the third time interval, the projector 214 may be turned off such that the virtual image light 223 is not projected onto either of the eyepieces 202-1, 202-2, as illustrated in FIG. 5C. After the third time interval, the method 800 may proceed to the first time interval or the second time interval.

[0072] In some embodiments, the method 800 includes the additional steps of (1) receiving a brightness value of the world light 232 from the ambient light sensor 234, and (2) determining a duration of one or more of the first, second, and third time intervals and / or a switching frequency between the first, second, and third time intervals based on the brightness value. For example, in response to receiving a high brightness value of the world light 232, indicative of bright outdoor conditions, the duration of the first time interval may be increased, the duration of the second time interval may be increased, and / or the duration of the third time interval may be reduced or eliminated. Additionally or alternatively, the dimming level of the dimmer may be increased. Conversely, in response to receiving a low brightness value of world light 232, indicative of low light indoor or nighttime conditions, the duration of the first time interval may be decreased, the duration of the second time interval may be decreased, and / or the duration of the third time interval may be increased. Additionally or alternatively, the dimming level of the dimmer may be decreased.

[0073] FIG. 9 illustrates a simplified computer system 900 according to an embodiment described herein. The computer system 900 as illustrated in FIG. 9 may be incorporated into a device such as the AR device 200 or 300 as described herein. FIG. 9 provides a schematic illustration of one example of a computer system 900 that may perform some or all of the steps of the method provided by various embodiments. It should be noted that FIG. 9 is intended only to provide a generalized illustration of the various components, any or all of which may be utilized as desired. FIG. 9 thus broadly illustrates a situation in which individual system elements may be implemented in a relatively separated manner or in a relatively more integrated manner.

[0074] Computer system 900 is shown to comprise hardware elements that may be electrically coupled via a bus 905 or may otherwise communicate as needed. The hardware elements may include one or more processors 910, including one or more general purpose processors and / or one or more special purpose processors, such as, but not limited to, digital signal processing chips, graphic acceleration processors, and / or the like, one or more input devices 915, which may include, but are not limited to, a mouse, a keyboard, a camera, and / or the like, and one or more output devices 920, which may include, but are not limited to, a display device, a printer, and / or the like.

[0075] The computer system 900 may further include and / or communicate with one or more non-transitory storage devices 925, which may comprise, but are not limited to, local and / or network accessible storage devices and / or may include, but are not limited to, disk drives, drive arrays, optical storage devices, solid-state storage devices such as random access memory ("RAM"), and / or read-only memory ("ROM"), which may be programmable, flash updatable, and / or the like. Such storage devices may be configured to implement any suitable data storage, including, but not limited to, various file systems, database structures, and / or the like.

[0076] The computer system 900 may also include a communication subsystem 919, which may include, but is not limited to, a modem, a network card (wireless or wired), an infrared communication device, a wireless communication device, and / or a chipset, such as, but not limited to, a Bluetooth device, an 802.11 device, a WiFi device, a WiMax device, a cellular communication facility, and / or the like. The communication subsystem 919 may include one or more input and / or output communication interfaces, allowing data to be exchanged with networks, such as networks described below to give as an example, other computer systems, televisions, and / or any other devices described herein. Depending on the desired functionality and / or other implementation concerns, a portable electronic device or similar device may communicate images and / or other information via the communication subsystem 919. In other embodiments, a portable electronic device, e.g., a first electronic device, may be incorporated into the computer system 900, e.g., an electronic device, as an input device 915. In some embodiments, the computer system 900 further comprises a working memory 935, which may include a RAM or ROM device as described above.

[0077] Computer system 900 may also include software elements, shown as currently residing in working memory 935, including operating system 940, device drivers, executable libraries, and / or other code, such as one or more application programs 945, that may comprise computer programs provided by various embodiments and / or that may be designed to implement methods and / or configure systems provided by other embodiments as described herein. By way of example only, one or more procedures described with respect to the methods discussed above may be implemented as code and / or instructions executable by a computer or a processor within a computer, and in certain aspects such code and / or instructions may then be used to configure and / or adapt a general-purpose computer or other device to perform one or more operations in accordance with the methods described.

[0078] A set of these instructions and / or code may be stored on a non-transitory computer-readable storage medium, such as storage device 925 described above. In some cases, the storage medium may be incorporated within a computer system, such as computer system 900. In other embodiments, the storage medium may be separate from the computer system, e.g., a removable medium, such as a compact disc, and / or may be provided within an installation package, such that the storage medium may be used to program, configure, and / or adapt a general-purpose computer with the instructions / code stored thereon. These instructions may take the form of executable code that is executable by computer system 900, and / or may take the form of source and / or installable code that, upon compilation and / or installation on computer system 900 using, for example, any of a variety of commonly available compilers, installation programs, compression / decompression utilities, and the like, then takes the form of executable code.

[0079] It will be apparent to those skilled in the art that substantial variations may be made according to specific requirements. For example, customized hardware may also be used and / or particular elements may be implemented in hardware, software, including portable software such as applets, or both. Furthermore, connection to other computing devices, such as network input / output devices, may also be employed.

[0080] As noted above, in one aspect, some embodiments may employ a computer system, such as computer system 900, to perform methods according to various embodiments of the present technology. According to one set of embodiments, some or all of the procedures of such methods are performed by computer system 900 in response to processor 910 executing one or more sequences of one or more instructions, which may be embedded in operating system 940, and / or other code, such as application program 945, contained in working memory 935. Such instructions may be read into working memory 935 from another computer-readable medium, such as one or more of storage devices 925. By way of example only, execution of a sequence of instructions contained in working memory 935 may cause processor 910 to perform one or more procedures of the methods described herein. Additionally or alternatively, some of the methods described herein may be performed through specialized hardware.

[0081] The terms "machine-readable medium" and "computer-readable medium" as used herein refer to any medium involved in providing data that causes a machine to operate in a tangible manner. In an embodiment implemented using computer system 900, various computer-readable media may be involved in providing instructions / code to processor 910 for execution and / or may be used to store and / or carry such instructions / code. In many implementations, computer-readable media are physical and / or tangible storage media. Such media may take the form of non-volatile or volatile media. Non-volatile media include, for example, optical and / or magnetic disks, such as storage device 925. Volatile media include dynamic memory, such as, but not limited to, working memory 935.

[0082] Common forms of physical and / or tangible computer readable media include, for example, a floppy disk, a flexible disk, a hard disk, magnetic tape or any other magnetic medium, a CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with a pattern of holes, RAM, PROM, EPROM, FLASH-EPROM, any other memory chip or cartridge, or any other medium from which a computer can read instructions and / or code.

[0083] Various forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to the processor 910 for execution. By way of example only, the instructions may initially be carried on a magnetic and / or optical disk of a remote computer. The remote computer may load the instructions into its dynamic memory and send the instructions as signals over a transparent medium to be received and / or executed by the computer system 900.

[0084] The communications subsystem 919 and / or its components generally receive signals and the bus 905 may then convey the signals and / or the data, instructions, etc. carried by the signals to the working memory 935, from which the processor 910 retrieves and executes the instructions. The instructions received by the working memory 935 may optionally be stored on a non-transitory storage device 925 either before or after execution by the processor 910.

[0085] The methods, systems, and devices discussed above are examples. Various configurations may omit, substitute, or add various procedures or components, as appropriate. For example, in alternative configurations, the method may be performed in a different order than described, and / or various steps may be added, omitted, and / or combined. Also, features described with respect to one configuration may be combined in various other configurations. Different aspects and elements of the configurations may be combined in a similar manner. Also, technology evolves, and thus many of the elements are examples and do not limit the scope of the disclosure or the claims.

[0086] Specific details are given in the description to provide a thorough understanding of the example configurations, including the implementation. However, the configurations may be practiced without these specific details. For example, well-known circuits, processes, algorithms, structures, and techniques are shown without unnecessary detail to avoid obscuring the configurations. This description provides only example configurations and does not limit the scope, applicability, or configuration of the claims. Rather, the foregoing description of the configurations will provide those skilled in the art with an effective description for implementing the described techniques. Various changes may be made in the function and arrangement of elements without departing from the spirit or scope of the present disclosure.

[0087] Also, the configurations may be described as processes, depicted as schematic flow charts or block diagrams. Although the operations may be described as sequential processes, many of the operations may be performed in parallel or simultaneously. In addition, the order of the operations may be rearranged. The processes may have additional steps not included in the figures. Furthermore, embodiments of the method may be implemented by hardware, software, firmware, middleware, microcode, hardware description languages, or any combination thereof. When implemented in software, firmware, middleware, or microcode, the program code or code segments for performing the necessary tasks may be stored in a non-transitory computer-readable medium, such as a storage medium. A processor may perform the tasks described.

[0088] Although several example configurations have been described, various modifications, alternative constructions, and equivalents may be used without departing from the spirit of the disclosure. For example, the aforementioned elements may be components of a larger system, and other rules may take precedence over or otherwise modify the application of the present technology. Also, some steps may take place before, during, or after the aforementioned elements are discussed. Thus, the foregoing description is not intended to be binding on the scope of the claims.

[0089] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Thus, for example, reference to a "user" includes a plurality of such users, reference to a "processor" includes reference to one or more processors and equivalents thereof known to those skilled in the art, and so forth.

[0090] Additionally, the words "comprise," "comprising," "contains," "containing," "include," "including," and "includes," when used in this specification and the claims that follow, are intended to specify the presence of stated features, integers, components, or steps, but they do not exclude the presence or addition of one or more other features, integers, components, steps, acts, or groups.

[0091] It should also be understood that the examples and embodiments described herein are for illustrative purposes only, and that various modifications or changes in light thereof will be suggested to those skilled in the art and are within the spirit and scope of the present application and the appended claims.

Claims

1. receiving light associated with a world object at an optical system; projecting light associated with a first virtual image onto a first eyepiece of the optical system and propagating a portion of the light associated with the first virtual image toward a user side of the optical system, the optical system further having a second eyepiece positioned between a world side of the optical system and the first eyepiece, the second eyepiece configured to outcouple light associated with a second virtual image toward the user side of the optical system; adjusting a dimmer of the optical system positioned between the first eyepiece and the second eyepiece to reduce an intensity of light associated with an artifact image impinging on the dimmer and an intensity of the light associated with the world object impinging on the dimmer; A method comprising:

2. ceasing to project the light associated with the first virtual image onto the first eyepiece; and adjusting the dimmer to allow light impinging on the dimmer to pass substantially through the dimmer. The method of claim 1 , further comprising:

3. Projecting light associated with the second virtual image onto the second eyepiece of the optical system and propagating a portion of the light associated with the second virtual image toward the user; and adjusting a second dimmer of the optical system positioned between the world side and the second eyepiece to reduce an intensity of light associated with a second artifact image impinging on the second dimmer and an intensity of the light associated with the world object impinging on the second dimmer. The method of claim 2 , further comprising:

4. resuming projecting the light associated with the first virtual image onto the first eyepiece; and adjusting the dimmer to reduce the intensity of the light associated with the artifact image impinging on the dimmer and the intensity of the light associated with the world object impinging on the dimmer. The method of claim 2 , further comprising:

5. receiving, from an ambient light sensor of the optical system, an intensity value of the light associated with the world object; The method of claim 2 , further comprising:

6. The method of claim 2, wherein projecting the light associated with the first virtual image onto the first eyepiece causes the light associated with the artifact image to propagate from the first eyepiece toward the dimmer.

7. The method of claim 1 , wherein the optical system is an augmented reality device.

8. 1. An optical system configured to receive light associated with a world object, the optical system comprising: A first eyepiece; a second eyepiece positioned between a world side of the optical system and the first eyepiece, the first eyepiece and the second eyepiece configured to outcouple light associated with a virtual image towards a user side of the optical system; a projector configured to project light associated with a first virtual image onto the first eyepiece and propagate a portion of the light associated with the first virtual image toward the user side of the optical system; a dimmer positioned between the first eyepiece and the second eyepiece, the dimmer configured to reduce an intensity of light associated with an artifact image impinging on the dimmer and an intensity of the light associated with the world object impinging on the dimmer; An optical system comprising:

9. The projector configured to stop projecting the light associated with the first virtual image onto the first eyepiece; The optical system of claim 8 , wherein the dimmer is configured to allow light impinging on the dimmer to pass substantially through the dimmer.

10. A second dimmer positioned between the world side of the optical system and the second eyepiece, the second dimmer configured to reduce an intensity of light associated with a second artifact image impinging on the second dimmer and an intensity of the light associated with the world object impinging on the second dimmer; The optical system of claim 9 further comprising:

11. The projector is configured to project light associated with a second virtual image onto the second eyepiece and propagate a portion of the light associated with the second virtual image toward the user.

11. The optical system of claim 10.

12. The projector configured to resume projecting the light associated with the first virtual image onto the first eyepiece; 10. The optical system of claim 9, wherein the dimmer is configured to reduce an intensity of the light associated with the artifact image impinging on the dimmer and an intensity of the light associated with the world object impinging on the dimmer.

13. an ambient light sensor configured to detect a brightness value of the light associated with the world object; The optical system of claim 9 further comprising:

14. The optical system of claim 8 , wherein the optical system is an augmented reality device.

15. A non-transitory computer readable medium comprising instructions that, when executed by a processor, cause the processor to perform operations for operating an optical system configured to receive light associated with a world object, the operations comprising: projecting light associated with a first virtual image onto a first eyepiece of the optical system and propagating a portion of the light associated with the first virtual image toward a user side of the optical system, the optical system further having a second eyepiece positioned between a world side of the optical system and the first eyepiece, the second eyepiece configured to outcouple light associated with a second virtual image toward the user side of the optical system; adjusting a dimmer of the optical system positioned between the first eyepiece and the second eyepiece to reduce an intensity of light associated with an artifact image impinging on the dimmer and an intensity of the light associated with the world object impinging on the dimmer; 16. A non-transitory computer readable medium comprising:

16. The operation further comprises: ceasing to project the light associated with the first virtual image onto the first eyepiece; and adjusting the dimmer to allow light impinging on the dimmer to pass substantially through the dimmer.

20. The non-transitory computer readable medium of claim 15, comprising:

17. The operation further comprises: projecting light associated with the second virtual image onto the second eyepiece of the optical system and propagating a portion of the light associated with the second virtual image towards the user side; and adjusting a second dimmer of the optical system positioned between the world side and the second eyepiece to reduce an intensity of light associated with a second artifact image impinging on the second dimmer and an intensity of the light associated with the world object impinging on the second dimmer.

20. The non-transitory computer readable medium of claim 16, comprising executing:

18. The operation further comprises: resuming projecting the light associated with the first virtual image onto the first eyepiece; and adjusting the dimmer to reduce the intensity of the light associated with the artifact image impinging on the dimmer and the intensity of the light associated with the world object impinging on the dimmer.

20. The non-transitory computer readable medium of claim 16, comprising executing:

19. The operation further comprises: receiving, from an ambient light sensor of the optical system, an intensity value of the light associated with the world object; 20. The non-transitory computer readable medium of claim 16, comprising:

20. 17. The non-transitory computer-readable medium of claim 16, wherein projecting the light associated with the first virtual image onto the first eyepiece causes the light associated with the artifact image to propagate from the first eyepiece towards the dimmer.

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