# Patent

## Title
Pixel opacity for augmented reality

## Abstract

In embodiments of pixel opacity for augmented reality, a display lens system includes a first display panel that displays a virtual image generated to appear as part of an environment viewed through optical lenses. A second display panel displays an environment image of the environment as viewed through the optical lenses, and the environment image includes opaque pixels that form a black silhouette of the virtual image. The display lens system also includes a beam-splitter panel to transmit light of the environment image and reflect light of the virtual image to form a composite image that appears as the virtual image displayed over the opaque pixels of the environment image.

## Background
BACKGROUND
Virtual reality can be viewed as a computer-generated simulated environment in which a user has an apparent physical presence. A virtual reality experience can be generated in 3D and viewed with a head-mounted display (HMD), such as glasses or other wearable display device that has near-eye display panels as lenses to display a virtual reality environment, which replaces the actual environment. Augmented reality, however, provides that a user can still see through the display lenses of the glasses or other wearable display device to view the surrounding environment, yet also see images of virtual objects that are generated for display and appear as a part of the environment. Augmented reality can include any type of input such as audio and haptic inputs, as well as virtual images, graphics, and video that enhances or augments the environment that a user experiences. As an emerging technology, there are many challenges and design constraints with augmented reality, from generation of the virtual objects and images so that they appear realistic in a real environment, to developing the optics small and precise enough for implementation with a wearable display device.
SUMMARY
This Summary introduces simplified concepts of pixel opacity for augmented reality, and the concepts are further described below in the Detailed Description and/or shown in the Figures. This Summary should not be considered to describe essential features of the claimed subject matter, nor used to determine or limit the scope of the claimed subject matter.
Pixel opacity for augmented reality is described. In embodiments, a display lens system includes a first display panel that displays a virtual image generated to appear as part of an environment viewed through optical lenses. A second display panel displays an environment image of the environment as viewed through the optical lenses, and the environment image includes opaque pixels that form a black silhouette of the virtual image. The display lens system also includes a beam-splitter panel to transmit light of the environment image and reflect light of the virtual image to form a composite image that appears as the virtual image displayed over the opaque pixels of the environment image.
In other embodiments, an imaging application generates the virtual image from virtual image data for display on the first display panel. The imaging application is implemented to correlate a location of the opaque pixels on the second display panel with a display position of the virtual image on the first display panel, and control pixel illumination of the second display panel to turn-off the opaque pixels, or otherwise spatially modulate the second display panel.



BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of pixel opacity for augmented reality are described with reference to the following Figures. The same numbers may be used throughout to reference like features and components that are shown in the Figures:
FIG. 1 illustrates an example imaging system in which embodiments of pixel opacity for augmented reality can be implemented.
FIGS. 2-4 illustrate additional examples of imaging systems in which embodiments of pixel opacity for augmented reality can be implemented.
FIG. 5 illustrates an example system that includes an example of a wearable display device in which embodiments of pixel opacity for augmented reality can be implemented.
FIG. 6 illustrates example method(s) of pixel opacity for augmented reality in accordance with one or more embodiments.
FIG. 7 illustrates various components of an example device that can implement embodiments of pixel opacity for augmented reality.



DETAILED DESCRIPTION
Embodiments of pixel opacity for augmented reality are described. As noted above, a challenge to the implementation of augmented reality is generating virtual images so that they appear realistic in a real environment when viewed by a user through a wearable display device, such as a head-mounted display (HMD). A virtual image, such as any type of object, video, text, graphic, and the like, may appear semi-translucent to a user when the virtual image is displayed over a real environment. Pixel opacity for augmented reality provides a technique to enhance the contrast of a virtual image relative to an environment image when the virtual image is displayed to appear as part of the environment, and without the virtual image appearing translucent.
In embodiments, an imaging application is implemented to generate a virtual image for display to appear as part of a surrounding environment when viewed by a user through left and right display lens systems of a wearable display device. The imaging application is also implemented to correlate the display position of the virtual image over an environment image, and then black-out pixels that correlate to the display position of the virtual image on a display panel that displays the environment image. The blacked-out pixels are opaque and form a filled-in outline, or black silhouette, of the virtual image in the environment image. Therefore, the virtual image does not appear translucent because there is no illumination behind the virtual image from the opaque pixels.
While features and concepts of pixel opacity for augmented reality can be implemented in any number of different devices, systems, environments, and/or configurations, embodiments of pixel opacity for augmented reality are described in the context of the following example devices, systems, and methods.
FIG. 1 illustrates an example imaging system 100 in which various embodiments of pixel opacity for augmented reality can be implemented. The example imaging system is representative of a refracting telescope having a one-to-one magnification through which a user can view the surrounding environment. The example imaging system includes various optical lenses of the refracting telescope. An objective lens 102 and an erector lens 104 project an environment image 106 on a display panel 108, such as a transparent LCD (liquid crystal display), or any other type of transmissive or reflective display panel. The imaging system also includes a display panel 110 to display a virtual image 112 that is generated to appear as part of the environment when viewed through the optical lenses of the imaging system. A virtual image may be any type of object, video, text, graphic, and the like that is generated for display as part of the environment in implementations of augmented reality.
In embodiments, the example imaging system 100 can be implemented as left and right display lens systems of a wearable display device, such as described with reference to FIG. 5. A wearable display device can be implemented as any type of glasses or head-mounted display (HMD) that includes implementations of the imaging system 100 (e.g., as left and right display lens systems) through which a user can view the surrounding environment, yet also see virtual images that are generated for display and appear as a part of the environment. The wearable display device and/or a controller unit for the wearable display device implements an imaging application, such as a software application, to implement embodiments of pixel opacity for augmented reality as described herein.
In embodiments, the imaging application generates the virtual image 112 for display on the display panel 110. The imaging application is also implemented to spatially modulate, or otherwise individually control the pixels of the display panel 108 for pixel-level opacity of the pixels that correlate to a display position of the virtual image 112 in the environment image 106. For example, the display panel 108 may be configured for pixel on-off control to block the light, and the imaging application controls the pixel illumination of the opaque pixels 114 that correlate to the display position of the virtual image. The opaque pixels form a filled-in outline, or black silhouette, of the virtual image in the environment image. In an alternate implementation, the imaging application can control blacking-out all of the display panel 108 and generating a completely new visual as the virtual image for display on the display panel 110.
The example imaging system 100 includes a beam-splitter panel 116 (also commonly referred to as a 50/50 mirror, or polarizing beam-splitter). The beam-splitter panel is implemented to transmit light of the environment image 106, and reflect light of the virtual image 112, through an eyepiece optic 118 to form a composite image 120 that appears as the virtual image displayed over the opaque pixels 114 of the environment image. The blacked-out, opaque pixels provide that the virtual image does not appear translucent, but rather appears with a high contrast relative to the environment image in the composite image.
FIG. 2 illustrates another example imaging system 200 in which various embodiments of pixel opacity for augmented reality can be implemented. Similar to the example imaging system described with reference to FIG. 1, the example imaging system 200 is representative of a refracting telescope having a one-to-one magnification through which a user can view the surrounding environment. The example imaging system can also be implemented as left and right display lens systems of a wearable display device, such as described with reference to FIG. 5.
The example imaging system 200 includes an objective lens 202 and an erector lens 204 that project an environment image 206 on a display panel 208, such as a reflective LCOS (liquid crystal on silicon) display, or any other type of reflective display panel (e.g., DLP or DMD). The environment image is reflected from a beam-splitter panel 210 (or polarizing beam-splitter panel) onto the display panel 208. The environment image is then reflected back from the display panel, through the beam-splitter panel 210, to a mirror panel 212. The imaging system also includes a display panel 214 to display a virtual image 216 that is generated to appear as part of the environment when viewed through the optical lenses of the imaging system. A second beam-splitter panel 218 is implemented to transmit light of the environment image 206, and reflect light of the virtual image 216, through an eyepiece optic 220 to form a composite image 222 that appears as the virtual image displayed over opaque pixels of the environment image.
Examples of an environment image, a virtual image, a composite image, and opaque pixels of the environment image are described with reference to the example imaging system shown in FIG. 1. Further, the imaging application is implemented to spatially modulate, or otherwise individually control the pixels of the display panel 208 for pixel-level opacity of the pixels that correlate to a display position of the virtual image in the environment image.
FIG. 3 illustrates another example imaging system 300 in which various embodiments of pixel opacity for augmented reality can be implemented. This example imaging system includes similar components described with reference to the imaging system shown in FIG. 2, in a different configuration. The example imaging system 300 can also be implemented as left and right display lens systems of a wearable display device, such as described with reference to FIG. 5.
The example imaging system 300 includes an objective lens 302 and an erector lens 304 that project an environment image 306 on a display panel 308, such as a reflective LCOS (liquid crystal on silicon) display, or any other type of reflective display panel (e.g., DLP or DMD). The environment image is reflected from a mirror panel 310 onto the display panel 308. The environment image is then reflected back from the display panel to a mirror panel 312. The imaging system also includes a display panel 314 to display a virtual image 316 that is generated to appear as part of the environment when viewed through the optical lenses of the imaging system. A beam-splitter panel 318 is implemented to transmit light of the environment image 306, and reflect light of the virtual image 316, through an eyepiece optic 320 to form a composite image 322 that appears as the virtual image displayed over opaque pixels of the environment image.
Examples of an environment image, a virtual image, a composite image, and opaque pixels of the environment image are described with reference to the example imaging system shown in FIG. 1. Further, the imaging application can be implemented to spatially modulate, or otherwise individually control the pixels of the display panel 308 for pixel-level opacity of the pixels that correlate to a display position of the virtual image in the environment image.
FIG. 4 illustrates another example imaging system 400 in which various embodiments of pixel opacity for augmented reality can be implemented. This example imaging system is implemented with reflective and refractive optical power components, such as with freeform prisms in an inverted configuration. Alternatively, the example imaging system may be implemented with reflective optical power components. The example imaging system 400 can also be implemented as left and right display lens systems of a wearable display device, such as described with reference to FIG. 5.
The example imaging system 400 includes a first reflective and refractive optical power element 402 that projects an environment image 404 up to a display panel 406, such as a reflective LCOS (liquid crystal on silicon) display, or any other type of reflective display panel (e.g., DLP or DMD). The environment image is reflected from the first reflective element 402, onto a mirror panel 408, and from a beam-splitter panel 410 to the display panel 406. The environment image is then reflected back from the display panel to the beam-splitter panel 410. The imaging system also includes a display panel 412 to display a virtual image 414 that is generated to appear as part of the environment when viewed through the reflective elements. The beam-splitter panel 410 is implemented to transmit light of the environment image 404, and reflect light of the virtual image 414, to a second reflective and refractive optical power element 416 to form a composite image 418 that appears as the virtual image displayed over opaque pixels of the environment image. In this example, the first and second reflective elements are implemented for total internal reflection (TIR) to reflect the light of the environment image and/or the virtual image.
Examples of an environment image, a virtual image, a composite image, and opaque pixels of the environment image are described with reference to the example imaging system shown in FIG. 1. Further, the imaging application can be implemented to spatially modulate, or otherwise individually control the pixels of the display panel 406 for pixel-level opacity of the pixels that correlate to a display position of the virtual image in the environment image.
In the example imaging system 400, the display panels 406 and 412, along with the mirror panel 408 and the beam-splitter panel 410, form an imaging unit 420 of the imaging system. In embodiments, the imaging unit 420 can be mounted on and/or integrated into the frame of a wearable display device, such as the wearable display device described with reference to FIG. 5. The imaging unit 420 can be integrated into the frame or mounted on top of the frame above a display lens of the wearable display device (also referred to as brow-mounted). Alternatively, the imaging unit 420 can be integrated into or mounted on the side of the frame of the wearable display device (also referred to as temple-mounted).
FIG. 5 illustrates an example system 500 that includes an example wearable display device 502 in which embodiments of pixel opacity for augmented reality can be implemented. The wearable display device can be implemented as any type of glasses or head-mounted display (HMD) that includes display lens systems 504 (e.g., left and right display lens systems) through which a user can view the surrounding environment, yet also see virtual images (e.g., any type of object, video, text, graphic, and the like) that are generated for display and appear as a part of the environment.
The wearable display device 502 can be implemented as an independent, portable system that includes memory, software, a processor, and/or a power source. Alternatively or in addition, the wearable display device may be communicatively linked to a controller 506 that includes any one or combination of the memory, software, processor, and/or power source, such as a battery unit. The controller can be implemented for wired or wireless communication with the wearable display device. The controller and/or the wearable display device can also be implemented with any number and combination of differing components as further described with reference to the example device shown in FIG. 7. For example, the controller and/or the wearable display device includes an imaging application implemented as computer-executable instructions, such as a software application, and executed by a processor to implement embodiments of pixel opacity for augmented reality as described herein.
In embodiments, the controller may be implemented as a dedicated device (e.g., the wired controller 506), as a mobile phone 508, a tablet or other portable computer device, a gaming system 510, or as any other type of electronic device that can be implemented to process and generate virtual images for display as part of the environment that is viewed through the display lens system of the wearable display device. The controller may communicate with the wearable display device wirelessly via WiFiTM, BluetoothTM, infrared (IR), RFID transmission, wireless Universal Serial Bus (WUSB), cellular, or via other wireless communication techniques.
The example system 500 also includes a data server 512, or data service, that communicates, or otherwise distributes, virtual image data 514 to the wearable display device 502 via a communication network 516. For example, the data server may be part of a network-based gaming system that generates virtual images for augmented reality display at the wearable display device. Alternatively, the data server may be part of a navigation system that communicates navigation directions and information for display in the display lens systems 504 of the wearable display device. In another example, the data server may be part of a messaging service, such as an e-mail or text messaging system, that communicates e-mail and/or text messages to the wearable display device for display in the display lens systems, where a user can read a message as an augmented reality image that is displayed over the environment viewed through the wearable display device.
Any of the devices, servers, and/or services can communicate via the communication network 516, which may be implemented to include wired and/or wireless networks. The communication network can also be implemented using any type of network topology and/or communication protocol, and can be represented or otherwise implemented as a combination of two or more networks, to include IP-based networks and/or the Internet. The communication network may also include mobile operator networks that are managed by mobile operators, such as a communication service provider, cell-phone provider, and/or Internet service provider.
The wearable display device 502 includes a frame 518, such as in the form of glasses, goggles, or any other structure, that supports and incorporates the various components of the device, as well as serves as a conduit for electrical and other component connections. A components module 520 (or components modules on the left, right, and/or both sides of the device frame) incorporates any of the various components, such as processing and control circuitry, memory, software, a processor, GPS transceiver, and/or power source. The wearable display device may also include a microphone 522 to record audio data from the surrounding environment, as well as ear phones for audio feedback as part of an augmented reality experience.
The wearable display device 502 also includes various cameras 524 that capture video and still images of the surrounding environment. The image and video data can be processed on the device and/or by a controller device (e.g., controller 506), and used to create a mapping field to orient and track a user in the environment space. The wearable display device can also include eye tracking cameras used to determine a user's eyeball location and track eye movements. The wearable display device may also include a temperature sensor, as well as inertial sensors for sensing position, orientation, and acceleration of the wearable display device.
An example of one display lens system 504 is shown from a viewer perspective 526 of the wearable display device 502, as if viewing the display lens system from the top of the device. The display lens system includes an imaging system 528, which can be implemented with any number of micro display panels, lenses, and reflecting elements to display and project a virtual image into a see-through and reflecting waveguide 530. A display lens system 504 and/or the imaging system 528 can be implemented as any of the imaging systems described with reference to the previous FIGS. 1-4 to implement embodiments of pixel opacity for augmented reality. The see-through, reflecting waveguide 530 is implemented for internal reflection and conducts the visible light 532 of a virtual image that is generated by the imaging unit for viewing by a user, and also passes through the light 534 from the surrounding environment for viewing by the user.
The micro display panels, lenses, and/or reflecting elements of the imaging system 528 can be implemented with various display technologies, such as implemented with a transparent LCD, or using a transmissive projection technology where the light source is modulated by optically active material, backlit with white light. These technologies can be implemented using LCD type displays with powerful backlights and high optical energy densities. Alternatively, a micro display and/or reflecting element can be implemented using a reflective technology, such as digital light processing (DLP) and liquid crystal on silicon (LCOS), that reflects external light, which is reflected and modulated by an optical material.
In embodiments, the imaging system 528 (or other components of a display lens system 504) can be implemented to include an infra-red (IR) laser utilized for system calibrations and/or as an illumination source for an eye-tracking system and camera that tracks the position of a user's eyes. The eye-tracking system includes the eye-tracking illumination source, which is not a visible light, and includes an eye-tracking IR sensor. The IR sensor can be implemented as an IR camera that provides infrared image data of the eye for eye-tracking processing, or an IR sensor that detects eye reflections when the eye is illuminated. The see-through and reflecting waveguide 530 can also be utilized for the infrared illumination, and for eyeball reflections that the eye-tracking system uses to track the position of the user's eyes.
In this example, the display lens systems 504 include an optional opacity filter 536, and a see-through lens 538 on each side of the waveguide 530. The see-through lenses can be standard eye-glass lenses and made to prescription (or no prescription). The opacity filter selectively blocks natural light, either uniformly or on a per-pixel basis, from passing through the see-through and reflecting waveguide to enhance the contrast of a displayed virtual image.
Example method 600 is described with reference to FIG. 6 in accordance with one or more embodiments of pixel opacity for augmented reality. Generally, any of the services, functions, methods, procedures, components, and modules described herein can be implemented using software, firmware, hardware (e.g., fixed logic circuitry), manual processing, or any combination thereof. A software implementation represents program code that performs specified tasks when executed by a computer processor. The example methods may be described in the general context of computer-executable instructions, which can include software, applications, routines, programs, objects, components, data structures, procedures, modules, functions, and the like. The program code can be stored in one or more computer-readable storage media devices, both local and/or remote to a computer processor. The methods may also be practiced in a distributed computing environment by multiple computer devices. Further, the features described herein are platform-independent and can be implemented on a variety of computing platforms having a variety of processors.
FIG. 6 illustrates example method(s) 600 of pixel opacity for augmented reality. The order in which the method blocks are described are not intended to be construed as a limitation, and any number of the described method blocks can be combined in any order to implement a method, or an alternate method.
At block 602, a virtual image is displayed on a first display panel. For example, the display panel 110 (FIG. 1) displays the virtual image 112 that is generated to appear as part of an environment viewed through the optical lenses of the imaging system 100. At block 604, an environment image of the environment is displayed on a second display panel. For example, the display panel 108 displays the environment image 106, including opaque pixels 114 that form a black silhouette of the virtual image. In embodiments, the imaging application 720 (FIG. 7) generates the virtual image for display to appear as part of the surrounding environment when viewed by a user through left and right display lens systems of a wearable display device 502 (FIG. 5).
At block 606, a location of opaque pixels on the second display panel is correlated with a display position of the virtual image on the first display panel and, at block 608, pixel illumination of the second display panel is controlled. For example, the imaging application 720 spatially modulates, or otherwise individually controls the pixels of the display panel 108 for pixel-level opacity of the pixels that correlate to the display position of the virtual image 112 in the environment image 106. The display panel 108 may be configured for pixel on-off control to block the light, and the imaging application controls the pixel illumination to turn-off the opaque pixels 114 that correlate to the display position of the virtual image.
At block 610, light of the environment image is transmitted through an eyepiece optic and, at block 612, light of the virtual image is reflected through the eyepiece optic. At block 614, a composite image is formed that appears as the virtual image displayed over opaque pixels of the environment image. For example, the beam-splitter panel 116 transmits light of the environment image 106 (e.g., as illuminated from the display panel 108), and reflects light of the virtual image 112 (e.g., as illuminated from the display panel 110), through an eyepiece optic 118 to form a composite image 120 that appears as the virtual image 112 displayed over the opaque pixels 114 of the environment image. The blacked-out, opaque pixels of the environment image provide that the virtual image does not appear translucent, but rather appears with a high contrast relative to the environment image in the composite image.
FIG. 7 illustrates various components of an example device 700 that can be implemented as any of the devices described with reference to the previous FIGS. 1-6, such as a wearable display device and/or a controller for a wearable display device. In embodiments, the device may be implemented as any one or combination of a fixed or mobile device, in any form of a consumer, computer, portable, communication, phone, navigation, appliance, gaming, media playback, and/or electronic device. The device may also be associated with a user (i.e., a person) and/or an entity that operates the device such that a device describes logical devices that include users, software, firmware, hardware, and/or a combination of devices.
The device 700 includes communication devices 702 that enable wired and/or wireless communication of device data 704, such as virtual image data, as well as video and images data, and other media content stored on the device. The media content stored on the device can include any type of audio, video, and/or image data. The device includes one or more data inputs 706 via which any type of data, media content, and/or inputs can be received, such as user-selectable inputs and any other type of audio, video, and/or image data received from any content and/or data source.
The device 700 also includes communication interfaces 708, such as any one or more of a serial, parallel, network, or wireless interface. The communication interfaces provide a connection and/or communication links between the device and a communication network by which other electronic, computing, and communication devices communicate data with the device.
The device 700 includes one or more processors 710 (e.g., any of microprocessors, controllers, and the like), which process computer-executable instructions to control the operation of the device. Alternatively or in addition, the device can be implemented with any one or combination of software, hardware, firmware, or fixed logic circuitry that is implemented in connection with processing and control circuits which are generally identified at 712. Although not shown, the device can include a system bus or data transfer system that couples the various components within the device. A system bus can include any one or combination of different bus structures, such as a memory bus or memory controller, a peripheral bus, a universal serial bus, and/or a processor or local bus that utilizes any of a variety of bus architectures.
The device 700 also includes one or more memory devices 714 (e.g., computer-readable storage media) that enable data storage, such as random access memory (RAM), non-volatile memory (e.g., read-only memory (ROM), flash memory, etc.), and a disk storage device. A disk storage device may be implemented as any type of magnetic or optical storage device, such as a hard disk drive, a recordable and/or rewriteable disc, and the like. The device may also include a mass storage media device. Computer-readable storage media can be any available medium or media that is accessed by a computing device.
A memory device 714 provides data storage mechanisms to store the device data 704, other types of information and/or data, and device applications 716. For example, an operating system 718 can be maintained as a software application with the memory device and executed on the processors. The device applications may also include a device manager or controller, such as any form of a control application, software application, signal processing and control module, code that is native to a particular device, a hardware abstraction layer for a particular device, and so on. In this example, the device applications also include an imaging application 720 that implements embodiments of pixel opacity for augmented reality as described herein.
The device 700 may also include an audio and/or video processing system 722 that generates audio data for an audio system 724 and/or generates display data for a display system 726. In implementations, the audio system and/or the display system are external components to the device. Alternatively, the audio system and/or the display system are integrated components of the example device.
Although embodiments of pixel opacity for augmented reality have been described in language specific to features and/or methods, the appended claims are not necessarily limited to the specific features or methods described. Rather, the specific features and methods are disclosed as example implementations of pixel opacity for augmented reality.

## Claims

1. A wearable display device, comprising:
a left display lens system configured to form a composite image for viewing;
a right display lens system configured to form the composite image for viewing;
the left and right display lens systems each comprising:
a display panel configured to display an environment image of an environment, the environment image including opaque pixels that form a black silhouette of a virtual image;
a first freeform prism inverted relative to a second freeform prism, the first freeform prism configured to project the environment image onto the display panel and the second freeform prism configured to reflect the composite image for viewing; and

the composite image formed with the virtual image displayed over the opaque pixels of the environment image to augment reality of the environment that is viewed through the left and right display lens systems.

2. A wearable display device as recited in claim 1, wherein each of the left and right display lens systems further comprise:
a second display panel configured to display the virtual image.

3. A wearable display device as recited in claim 2, further comprising a computer processing system to implement an imaging application that is configured to spatially modulate the display panel of the left and right display lens systems to correlate a location of the opaque pixels with a display position of the virtual image on the second display panel of the left and right display lens systems.

4. A wearable display device as recited in claim 2, further comprising a controller that includes a computer processing system to implement an imaging application configured to:
correlate a location of the opaque pixels on the display panel of the left and right display lens systems with a display position of the virtual image on the second display panel of the left and right display lens systems; and
control pixel illumination of the display panel of the left and right display lens systems to turn-off the opaque pixels.

5. A wearable display device as recited in claim 1, further comprising a camera configured to capture the environment image for pixelated display on the display panel.

6. An imaging system, comprising:
a first display panel configured to display an environment image of the environment, the environment image including opaque pixels that form a black silhouette of a virtual image;
a first freeform prism configured to project the environment image onto the first display panel;
a second display panel configured to display the virtual image; and
a second freeform prism inverted relative to the first freeform prism configured to reflect a composite image that appears as the virtual image displayed over the opaque pixels of the environment image.

7. An imaging system as recited in claim 6, wherein the virtual image appears with a high contrast relative to the environment image in the composite image.

8. An imaging system as recited in claim 6, further comprising a camera configured to capture the environment image for pixelated display on the first display panel.

9. An imaging system as recited in claim 6, wherein the first display panel is one of a transparent LCD or a reflective LCOS, the first display panel comprised of pixels configured for on-off control, and wherein the opaque pixels are turned off.

10. An imaging system as recited in claim 6, further comprising an imaging application configured to spatially modulate the first display panel to correlate a location of the opaque pixels with a display position of the virtual image on the second display panel.

11. An imaging system as recited in claim 6, further comprising:
a mirror panel configured to reflect the environmental image received from the first freeform prism to a beam-splitter that is configured to reflect the environmental image to the first display panel.

12. An imaging system as recited in claim 11, wherein the beam splitter is further configured to transmit light of the environmental image and reflect light of the virtual image to the second freeform prism.

13. A imaging system as recited in claim 6, wherein the first display panel, the first freeform prism, the second display panel, and the second freeform prism are integrated into or mounted on the side of the frame of a wearable display device.

14. A imaging system as recited in claim 6, wherein the first display panel, the first freeform prism, the second display panel, and the second freeform prism are integrated into or mounted on top of a display lens of a wearable display device.

15. An imaging system as recited in claim 6, further comprising an imaging application configured to:
generate the virtual image from virtual image data for display on the second display panel;
correlate a location of the opaque pixels on the first display panel with a display position of the virtual image on the second display panel; and
control pixel illumination of the first display panel to turn-off the opaque pixels.

16. A method comprising:
projecting an environment image of an environment onto a first display panel using a first freeform prism;
displaying the environment image on the first display panel, the environment image configured to include opaque pixels that form a black silhouette of a virtual image;
displaying the virtual image on a second display panel; and
forming a composite image with the virtual image displayed over the opaque pixels of the environment image, the composite image configured to be reflected for viewing via a second freeform prism that is inverted relative to the first freeform prism.

17. A method as recited in claim 16, wherein the virtual image appears with a high contrast relative to the environment image in the composite image.

18. A method as recited in claim 16, further comprising capturing the environment image with a camera for pixelated display on the first display panel.

19. A method as recited in claim 16, further comprising correlating a location of the opaque pixels on the first display panel with a display position of the virtual image on the second display panel.

20. A method as recited in claim 16, further comprising controlling pixel illumination of the first display panel to turn-off the opaque pixels.