High-resolution LCD display

Abstract

This disclosure relates to a high-resolution liquid crystal display. Various embodiments illustrate a high-resolution liquid crystal display and its components. In some embodiments, light emitted by a high-resolution green liquid crystal display is combined with light emitted by at least one lower-resolution red and blue liquid crystal display via a combiner. The red and blue displays may include a single display or two displays located on opposite sides of the combiner. The combiner may be a dichroic element-based or polarized combiner. The combined light from the green display and the red and blue displays is directed toward the observer's eye through collimating optics such as a pancake lens or a Fresnel lens.

Description

Technical Field

[0001] Embodiments of the present disclosure relate generally to display systems, and more particularly to high resolution liquid crystal displays. Background Art

[0002] Description of Related Technology

[0003] The content displayed by the artificial reality system may include fully generated content or generated content combined with captured (e.g., real-world) content. One limitation to generating high-resolution and large field-of-view (FOV) content is the lack of displays with small pixel pitches and high pixel counts. In addition, some artificial reality systems, such as head-mounted displays (HMDs), include pancake lenses, which are reflective optical systems that are relatively compact but provide limited optical transmission. Very bright displays are often required to balance the limited optical transmission of the pancake lenses.

[0004] A conventional color liquid crystal display (LCD) typically includes a backlight, such as one or more light emitting diodes (LEDs), and an array of LCD pixels. Each pixel includes red, green, and blue sub-pixels with corresponding color filters for rendering red, green, and blue.

[0005] LCD backlights can be designed to meet the brightness requirements of artificial reality systems including HMDs. However, the pixel pitch of conventional color LCDs is limited (approximately 20 to 25 microns). Therefore, conventional color LCDs have limited practicality in some artificial reality systems (such as HMDs) that require smaller pixel pitches and higher pixel counts. Summary of the invention

[0006] One embodiment of the present disclosure provides a display system. The display system includes a first display configured to emit light within a first wavelength range, and a second display configured to emit light within at least one other wavelength range. The display system also includes a combiner element. In addition, the display system includes a collimating optical element.

[0007] In some embodiments, a first wavelength range may be associated with the color green and at least one other wavelength range associated with the color red and blue.

[0008] In some embodiments, the first display may include a green light emitting diode or a quantum dot layer embedded in a backlight unit.

[0009] In some embodiments, the first display may be positioned such that light within a first wavelength range is transmitted by the combiner element; and the second display is positioned such that light within at least one other wavelength range is reflected by the combiner element.

[0010] In some embodiments, the combiner element may be one of a polarization-based combiner or a dichroic element.

[0011] In some embodiments, the collimating optical element can be a pancake lens.

[0012] In some embodiments, the display system may further include: a third display configured to emit light within at least one other wavelength range, wherein the second display and the third display are each configured to display half of the image.

[0013] In some embodiments, the collimating optical element may be a Fresnel lens.

[0014] In some embodiments, the first wavelength range may be associated with the color green, at least one other wavelength range is associated with the color red, and the display system further includes a third display configured to emit light in a wavelength range associated with the color blue.

[0015] In some embodiments, the combiner element may be a crossed dichroic prism.

[0016] In some embodiments, a pixel in a display system may include sub-pixels having a 1:2 aperture ratio or a 1:1 aperture ratio.

[0017] In some embodiments, the first display and the second display may be liquid crystal displays (LCDs).

[0018] Another embodiment of the present disclosure provides a head mounted display (HMD). The HMD includes a display system, the display system including a first display configured to emit light within a first wavelength range and a second display configured to emit light within at least one other wavelength range. The display system also includes a combiner element. In addition, the display system includes a collimating optical element.

[0019] In some embodiments, the first wavelength range may be associated with the color green; at least one other wavelength range is associated with the color red and the color blue; and the first display has a higher resolution than the second display.

[0020] In some embodiments, the combiner element can be one of: a dichroic element, a crossed dichroic prism, or a polarization-based combiner.

[0021] In some embodiments, the collimating optical element can be one of a pancake lens or a Fresnel lens.

[0022] In some embodiments, a pixel in a display system may include sub-pixels having a 1:2 aperture ratio or a 1:1 aperture ratio.

[0023] Another embodiment of the present disclosure provides a method. The method includes emitting light within a first wavelength range via a first display, and emitting light within at least one other wavelength range via a second display. The method also includes combining the light within the first wavelength range with the light within at least one other wavelength range via a combiner element to generate a combined light. In addition, the method includes passing the combined light through a collimating optical element.

[0024] In some embodiments, a first wavelength range may be associated with the color green and at least one other wavelength range associated with the color red and blue.

[0025] In some embodiments, combining light in the first wavelength range with light in at least one other wavelength range may include transmitting light in the first wavelength range via a combiner element; and reflecting light in the at least one other wavelength range via the combiner element.

[0026] It should be understood that any feature described herein as suitable for incorporation into one or more aspects or embodiments of the present invention is intended to be generalizable to any and all aspects and embodiments of the present disclosure. Other aspects of the present disclosure may be understood by those skilled in the art based on the description, claims, and drawings of the present disclosure. The foregoing general description and the following detailed description are merely exemplary and illustrative, and are not limitations of the claims.

[0027] One advantage of the display system disclosed herein is that a higher display resolution can be achieved relative to a conventional color LCD. In addition, the display system disclosed herein can be brighter than a conventional color LCD, especially for green light. Therefore, the display system disclosed herein can be more suitable for some artificial reality systems (such as HMDs) than conventional color LCDs. These technical advantages represent one or more technical advances relative to prior art methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order that the manner in which the above-recited features of the various embodiments may be understood in detail, a more particular description of the disclosed concepts briefly summarized above may be made by reference to various embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the drawings illustrate only typical embodiments of the disclosed concepts and are therefore not to be considered limiting of the scope in any way, and that other equally effective embodiments exist.

[0029] Figure 1A is a diagram of a near eye display (NED) according to various embodiments;

[0030] Figure 1B yes Figure 1A A cross-sectional view of the front rigid body of the illustrated embodiment of the NED;

[0031] Figure 2Ais a diagram of a head mounted display (HMD) implemented as a NED according to various embodiments;

[0032] Figure 2B is implemented as a near-eye display according to various embodiments Figure 2A A cross-sectional view of an HMD;

[0033] Figure 3 is a block diagram of a NED system according to various embodiments.

[0034] Figure 4 is a schematic diagram showing a display system according to various embodiments;

[0035] Figure 5 is a schematic diagram showing a pixel geometry used in a conventional color liquid crystal display (LCD) according to the prior art;

[0036] Figure 6 It is to show that according to various embodiments, Figure 4 A schematic diagram of a pixel geometry in a display system;

[0037] Figure 7 is a diagram showing a method for use according to various embodiments Figure 4 Schematic diagram of an alternative pixel geometry in a display system;

[0038] Figure 8 is a schematic diagram showing a display system including two red and blue displays according to various embodiments;

[0039] Fig. 9 The following are more detailed descriptions of various embodiments. Figure 8 Display system;

[0040] Fig.10 is a schematic diagram showing a display system including a Fresnel lens according to various embodiments;

[0041] Fig.11 According to various embodiments, it is shown in more detail Fig.10 green displays, beam splitters and Fresnel lenses;

[0042] Fig.12 is a schematic diagram illustrating a display system including a crossed dichroic prism according to various embodiments;

[0043] Fig.13 According to various embodiments, Fig.12 A schematic diagram of the pixel geometry of a display system; and

[0044] Fig.14is a flow chart of method steps for displaying an image according to various embodiments. DETAILED DESCRIPTION

[0045] In the following description, numerous specific details are set forth to provide a more thorough understanding of various embodiments. However, it will be apparent to one skilled in the art that the disclosed concepts may be practiced without one or more of these specific details.

[0046] Configuration Overview

[0047] One or more embodiments disclosed herein relate to high-resolution liquid crystal displays (LCDs). In some embodiments, light emitted by a high-resolution green liquid crystal display is combined with light emitted by at least one lower resolution red and blue liquid crystal display via a combiner. The (multiple) red and blue display may include a single display or two displays located on opposite sides of the combiner. The combiner may be a dichroic element or a polarization-based combiner. The combined light from the green display and the (multiple) red and blue display is directed toward the eye of an observer through collimating optics such as a pancake lens or a Fresnel lens.

[0048] Since the human eye is most sensitive to green light, the use of a higher resolution green display allows for improved resolution relative to conventional color LCDs. In this regard, some embodiments employ a sub-pixel aperture ratio of 1:2 or 1:1, which allows the sub-pixels and pixels of the display system to be smaller than those in conventional color LCDs. Thus, higher display resolutions can be achieved relative to conventional color LCDs. In addition, a green display including a green light emitting diode (LED) or a quantum dot (QD) layer embedded in a backlight unit (BLU) can be used to achieve higher transmittance of green light relative to conventional color LCDs that rely on color filters.

[0049] Embodiments of the present disclosure may also include an artificial reality system or be implemented in conjunction with an artificial reality system. Artificial reality is a form of reality that has been adjusted in some way before being presented to a user, which may include, for example, a virtual reality (VR) system, an augmented reality (AR) system, a mixed reality (MR) system, a mixed reality system, or some combination and / or derivative thereof. Artificial reality content may include, but is not limited to, fully generated content or generated content combined with captured (e.g., real-world) content. Artificial reality content may include, but is not limited to, video, audio, tactile feedback, or some combination thereof. Artificial reality content may be presented in a single channel or multiple channels (such as stereoscopic video that generates a three-dimensional effect for the viewer). In addition, in some embodiments, the artificial reality system may also be associated with an application, product, accessory, service, or some combination thereof, which is used, for example, to create content in an artificial reality system and / or otherwise used for (e.g., performing activities in an artificial reality system) an artificial reality system. The artificial reality system can be implemented on a variety of platforms, including a head-mounted display (HMD) connected to a host computer system, a standalone HMD, a mobile device or computing system, or any other hardware platform capable of providing artificial reality content to one or more viewers.

[0050] System Overview

[0051] Figure 1A is a wiring diagram of a near eye display (NED) 100 according to various embodiments. Although NED and head mounted display (HMD) are disclosed herein as reference examples, a display device including a high-resolution liquid crystal display system may also be configured to be placed near one or more eyes of a user at a fixed position, rather than being head mounted (for example, the display device may be installed in a vehicle such as a car or an airplane for placement in front of one or more eyes of the user).

[0052] As shown, NED 100 includes front rigid body 105 and belt 110. Front rigid body 105 includes one or more electronic display elements of an electronic display (not shown), an inertial measurement unit (IMU) 115, one or more position sensors 120, and a positioner 125. Figure 1A As shown, position sensor 120 is located within IMU 115, and neither IMU 115 nor position sensor 120 is visible to a user. In various embodiments where NED 100 is used as an AR or MR device, portions of NED 100 and / or its internal components are at least partially transparent.

[0053] Figure 1B yes Figure 1AA cross-section 160 of the front body 105 of an embodiment of the NED 100 is shown. As shown, the front body 105 includes an electronic display 130 and an optical block 135 that together provide image light to an exit pupil 145. The exit pupil 145 is the location of the front body 105 where the user's eye 140 may be located. For purposes of illustration, Figure 1B A cross section 160 is shown associated with a single eye 140, but another optical block separate from the optical block 135 may provide altered image light to the user's other eye. In addition, the NED 100 includes an eye tracking system ( Figure 1B ). The eye tracking system may include one or more light sources that illuminate one or both eyes of the user. The eye tracking system may also include one or more cameras that capture images of one or both eyes of the user to track the position of the eyes.

[0054] Electronic display 130 displays images to the user. In various embodiments, electronic display 130 may include a single electronic display or multiple electronic displays (e.g., a display for each eye of the user). Examples of electronic display 130 include: a liquid crystal display (LCD), an organic light emitting diode (OLED) display, an active matrix organic light emitting diode display (AMOLED), QOLED, QLED, some other display, or some combination thereof.

[0055] Optical block 135 adjusts the orientation of image light emitted from electronic display 130 so that electronic display 130 appears at a specific virtual image distance from the user. Optical block 135 is configured to receive image light emitted from electronic display 130 and direct the image light to an eye box associated with exit pupil 145. The image light directed to the eye box forms an image at the retina of eye 140. The eye box is the area that defines how much the eye 140 can move up / down / left / right without a significant drop in image quality. Figure 1B In the illustration of , field of view (FOV) 150 is the extent of the observable world seen by eye 140 at any given moment.

[0056] In addition, in some embodiments, the optical block 135 amplifies the received light, corrects optical errors associated with the image light, and presents the corrected image light to the eye 140. The optical block 135 may include one or more optical elements 155 in optical series. The optical element 155 may be an aperture, a Fresnel lens, a convex lens, a concave lens, a filter, a waveguide, a Pancharatnam-Berry phase (PBP) lens or grating, a color selective filter, a wave plate, a C-plate, or any other suitable optical element 155 that affects the image light. In addition, the optical block 135 may include a combination of different optical elements. One or more optical elements in the optical block 135 may have one or more coatings (such as an anti-reflective coating).

[0057] In some embodiments, electronic display 130 and optical block 135 may include components of a high-resolution liquid crystal display system, as described below in conjunction with Figure 4 and Figures 6 to 13 An example of this is discussed in more detail.

[0058] Figure 2A 1 is a diagram of an HMD 162 implemented as a NED according to various embodiments. As shown, the HMD 162 is in the form of an augmented reality glasses pair. The HMD 162 presents computer-generated media to the user and enhances the view of the physical, real environment with the computer-generated media. Examples of computer-generated media presented by the HMD 162 include one or more images, videos, audio, or some combination thereof. In some embodiments, audio is presented via an external device (e.g., a speaker and headphones) that receives audio information from the HMD 162, a console (not shown), or both, and audio data is presented based on the audio information. In some embodiments, the HMD 162 can be modified to also operate as a VR HMD, an MR HMD, or some combination thereof. The HMD 162 includes a frame 175 and a display 164. As shown, the frame 175 mounts the NED to the user's head, and the display 164 provides image light to the user. The display 164 can be customized to various shapes and sizes to fit different styles of eyeglass frames.

[0059] Figure 2B is implemented as a NED according to various embodiments Figure 2A 1. A cross-sectional view of an HMD 162 of FIG. 1. The view includes the frame 175, the display 164 (which includes the display assembly 180 and the display block 185), and the eye 170. The display assembly 180 provides image light to the eye 170. The display assembly 180 houses the display block 185, which in different embodiments encloses different types of imaging optics and redirection structures. For illustration purposes, Figure 2BA cross section associated with a single display block 185 and a single eye 170 is shown, but in an alternative embodiment not shown, Figure 2B Another display block separated from the illustrated display block 185 provides image light to the user's other eye.

[0060] As shown, the display block 185 is configured to combine light from the local area with light from the computer-generated image to form an enhanced scene. The display block 185 is also configured to provide the enhanced scene to the eye box 165 corresponding to the position of the user's eye 170. The display block 185 may include, for example, a waveguide display, a focusing component, a compensation component, or some combination thereof. In some embodiments, the display block 185 may include the following in combination Figure 4 and Figures 6 to 13 One or more components of a high resolution liquid crystal display system are discussed in detail.

[0061] The HMD 162 may include one or more other optical elements between the display block 185 and the eye 170. The optical element may be used, for example, to correct aberrations in the image light emitted from the display block 185, to amplify the image light emitted from the display block 185, to make some other optical adjustments to the image light emitted from the display block 185, or some combination thereof. Examples of optical elements may include an aperture, a Fresnel lens, a convex lens, a concave lens, a filter, or any other suitable optical element that affects the image light. The display block 185 may also include one or more materials (e.g., plastic, glass, etc.) having one or more refractive indices that are effective to minimize weight and widen the field of view of the HMD 162.

[0062] Figure 3 is a block diagram of an embodiment of a near eye display system 300 in which a console 310 operates. In some embodiments, the NED system 300 corresponds to the NED 100 or the HMD 162. The NED system 300 may operate in a VR system environment, an AR system environment, an MR system environment, or some combination thereof. Figure 3 The illustrated NED system 300 includes a NED 305 and an input / output (I / O) interface 315 coupled to a console 310 .

[0063] Although Figure 3An example NED system 300 is shown that includes one NED 305 and one I / O interface 315, but in other embodiments, any number of these components may be included in the NED system 300. For example, there may be multiple NEDs 305, each NED 305 having an associated I / O interface 315, wherein each NED 305 and I / O interface 315 communicates with a console 310. In alternative configurations, different and / or additional components may be included in the NED system 300. Furthermore, in some embodiments, the various components included in the NED 305, the console 310, and the I / O interface 315 may be combined in a manner that is convenient for the user to use. Figure 3 The described approach may be distributed in different ways. For example, some or all of the functionality of console 310 may be provided by NED 305.

[0064] The NED 305 may be a head mounted display that presents content to a user. The content may include virtual and / or augmented views of a physical, real world environment that includes computer generated elements (e.g., two-dimensional or three-dimensional images, two-dimensional or three-dimensional video, sound, etc.). In some embodiments, the NED 305 may also present audio content to the user. The NED 305 and / or console 310 may transmit the audio content to an external device via the I / O interface 315. The external device may include various forms of speaker systems and / or headphones. In various embodiments, the audio content is synchronized with the visual content displayed by the NED 305.

[0065] NED 305 may include one or more rigid bodies that may be rigidly or non-rigidly coupled together. Rigid coupling between rigid bodies enables the coupled rigid bodies to function as a single rigid entity. In contrast, non-rigid coupling between rigid bodies allows the rigid bodies to move relative to each other.

[0066] like Figure 3 As shown, NED 305 may include a depth camera assembly (DCA) 320, a display 325, an optical assembly 330, one or more position sensors 335, an inertial measurement unit (IMU) 340, an eye tracking system 345, and a zoom module 350. In some embodiments, display 325 and optical assembly 330 may be integrated together into a projection assembly. Various embodiments of NED 305 may have more, fewer, or different components than those listed above. In addition, in various embodiments, the functionality of each component may be partially or completely covered by the functionality of one or more other components.

[0067] The DCA 320 captures sensor data describing depth information of the area surrounding the NED 305. The sensor data may be generated by one or a combination of depth imaging techniques such as triangulation, structured light imaging, time-of-flight imaging, laser scanning, etc. The DCA 320 may use the sensor data to calculate various depth characteristics of the area surrounding the NED 305. Additionally or alternatively, the DCA 320 may transmit the sensor data to the console 310 for processing.

[0068] The DCA 320 includes an illumination source, an imaging device, and a controller. The illumination source emits light onto an area surrounding the NED 305. In one embodiment, the emitted light is structured light. The illumination source includes multiple emitters, each of which emits light having certain characteristics (e.g., wavelength, polarization, coherence, temporal behavior, etc.). The characteristics between the emitters may be the same or different, and the emitters may operate simultaneously or individually. In one embodiment, the multiple emitters may be, for example, laser diodes (such as edge emitters), inorganic or organic light emitting diodes (LEDs), vertical cavity surface emitting lasers (VCSELs), or some other sources. In some embodiments, a single emitter or multiple emitters in the illumination source may emit light having a structured light pattern. In addition to the light reflected from objects in the environment generated by the multiple emitters, the imaging device also captures ambient light in the environment surrounding the NED 305. In various embodiments, the imaging device may be an infrared camera or a camera configured to operate in the visible spectrum. The controller coordinates how the illumination source emits light and how the imaging device captures light. For example, the controller may determine the brightness of the emitted light. In some embodiments, the controller also analyzes the detected light to detect objects in the environment and position information associated with these objects.

[0069] The display 325 displays a two-dimensional or three-dimensional image to the user based on the pixel data received from the console 310. In various embodiments, the display 325 includes a single display or multiple displays (e.g., a separate display for each eye of the user). In some embodiments, the display 325 includes a single or multiple waveguide displays. Light can be coupled to a single or multiple waveguide display via, for example, an LCD, an organic light emitting diode (OLED) display, an inorganic light emitting diode (ILED) display, an active matrix organic light emitting diode (AMOLED) display, a transparent organic light emitting diode (TOLED) display, a laser-based display, one or more waveguides, other types of displays, scanners, one-dimensional arrays, etc. In addition, a combination of display types can be incorporated into the display 325 and used separately, in parallel, and / or in combination.

[0070] Optical assembly 330 amplifies image light received from display 325, corrects optical errors associated with the image light, and presents the corrected image light to a user of NED 305. Optical assembly 330 includes a plurality of optical elements. For example, one or more of the following optical elements may be included in optical assembly 330: an aperture, a Fresnel lens, a convex lens, a concave lens, a filter, a reflective surface, or any other suitable optical element that deflects, reflects, refracts, and / or changes the image light in some manner. In addition, optical assembly 330 may include a combination of different optical elements. In some embodiments, one or more optical elements in optical assembly 330 may have one or more coatings (such as partially reflective or anti-reflective coatings). Optical assembly 330 may be integrated into a projection assembly (e.g., a projection assembly). In one embodiment, optical assembly 330 includes optical block 155.

[0071] In operation, optical assembly 330 magnifies and focuses the image light generated by display 325. In this way, optical assembly 330 makes display 325 physically smaller, lighter, and consumes less power than a display that does not use optical assembly 330. In addition, magnification can increase the field of view of the content presented by display 325. For example, in some embodiments, the field of view of the displayed content partially or completely uses the user's field of view. For example, the field of view of the displayed image can reach or exceed 310 degrees. In various embodiments, the amount of magnification can be adjusted by adding or removing optical elements.

[0072] In some embodiments, optical component 330 can be designed to correct one or more types of optical errors. Examples of optical errors include barrel or pincushion distortion, longitudinal chromatic aberration, or lateral chromatic aberration. Other types of optical errors may include spherical aberration, chromatic aberration, or errors caused by lens field curvature, astigmatism, in addition to other types of optical errors. In some embodiments, the visual content transmitted to display 325 is pre-distorted, and when the image light from display 325 transmits the various optical elements of optical component 330, optical component 330 corrects the distortion. In some embodiments, the optical elements of optical component 330 are integrated into display 325 as a projection component that includes at least one waveguide coupled to one or more optical elements. In some embodiments, display 325 and / or optical component 330 may include the following in combination Figures 4 to 7 The peripheral display system or its components discussed.

[0073] In some embodiments, the display 325 and the optical assembly 330 may include the following in combination: Figure 4 and Figures 6 to 13 One or more components of a high resolution liquid crystal display system are discussed in detail.

[0074] The IMU 340 is an electronic device that generates data indicating the position of the NED 305 based on measurement signals received from one or more position sensors 335 and depth information received from the DCA 320. In some embodiments of the NED 305, the IMU 340 may be a dedicated hardware component. In other embodiments, the IMU 340 may be a software component implemented in one or more processors.

[0075] In operation, position sensor 335 generates one or more measurement signals in response to the movement of NED 305. Examples of position sensor 335 include: one or more accelerometers, one or more gyroscopes, one or more magnetometers, one or more altimeters, one or more inclinometers, and / or various types of sensors for motion detection, drift detection, and / or error detection. Position sensor 335 can be located external to IMU 340, internal to IMU 340, or some combination thereof.

[0076] Based on one or more measurement signals from one or more position sensors 335, the IMU 340 generates data indicating an estimated current position of the NED 305 relative to an initial position of the NED 305. For example, the position sensors 335 may include a plurality of accelerometers for measuring translational motion (forward / backward, up / down, left / right) and a plurality of gyroscopes for measuring rotational motion (e.g., pitch, yaw, and roll). In some embodiments, the IMU 340 rapidly samples the measurement signals and calculates the estimated current position of the NED 305 based on the sampled data. For example, the IMU 340 may integrate the measurement signals received from the accelerometers over time to estimate a velocity vector, and integrate the velocity vector over time to determine the estimated current position of a reference point on the NED 305. Alternatively, the IMU 340 provides the sampled measurement signals to the console 310, which analyzes the sampled data to determine one or more measurement errors. The console 310 may also transmit one or more control signals and / or measurement errors to the IMU 340 to configure the IMU 340 to correct and / or reduce one or more measurement errors (e.g., drift errors). A reference point is a point that can be used to describe the position of the NED 305. A reference point may generally be defined as a point in space or a location that is related to the position and / or orientation of the NED 305.

[0077] In various embodiments, the IMU 340 receives one or more parameters from the console 310. The one or more parameters are used to keep track of the NED 305. Based on the received parameters, the IMU 340 can adjust one or more IMU parameters (e.g., sampling rate). In some embodiments, certain parameters cause the IMU 340 to update the initial position of the reference point so that it corresponds to the next position of the reference point. Updating the initial position of the reference point as the next calibration position of the reference point helps reduce drift errors when detecting the current position estimate of the IMU 340.

[0078] In some embodiments, an eye tracking system 345 is integrated into the NED 305. The eye tracking system 345 may include one or more illumination sources and imaging devices (cameras). In operation, when a user wears the NED 305, the eye tracking system 345 generates and analyzes tracking data related to the user's eyes. The eye tracking system 345 may also generate eye tracking information, which may include information about the position of the user's eyes (i.e., information about the angle at which the eyes are looking).

[0079] In some embodiments, zoom module 350 is also integrated into NED 305. Zoom module 350 can be communicatively coupled to eye tracking system 345 to enable zoom module 350 to receive eye tracking information from eye tracking system 345. Zoom module 350 can also modify the focus of image light emitted from display 325 based on the eye tracking information received from eye tracking system 345. Thus, zoom module 350 can reduce the vergence accommodation conflict that may arise when the user's eyes resolve the image light. In various embodiments, zoom module 350 can be engaged (e.g., mechanically or electrically) with at least one optical element of optical assembly 330.

[0080] In operation, zoom module 350 may adjust the position and / or orientation of one or more optical elements in optical assembly 330 in order to adjust the focus of image light propagating through optical assembly 330. In various embodiments, zoom module 350 may use eye tracking information obtained from eye tracking system 345 to determine how to adjust one or more optical elements in optical assembly 330. In some embodiments, zoom module 350 may perform foveal rendering of image light based on the eye tracking information obtained from eye tracking system 345 in order to adjust the resolution of image light emitted by display 325. In this case, zoom module 350 configures display 325 to display a high pixel density in a foveal region where the user's eye is focused, and a low pixel density in other areas where the user's eye is focused.

[0081] The I / O interface 315 facilitates the delivery of action requests from the user to the console 310. In addition, the I / O interface 315 facilitates the delivery of device feedback from the console 310 to the user. An action request is a request to perform a specific action. For example, an action request may be an instruction to start or end the capture of image or video data, or an instruction to perform a specific action within an application, such as pausing video playback, increasing or decreasing the volume of audio playback, etc. In various embodiments, the I / O interface 315 may include one or more input devices. Example input devices include: a keyboard, a mouse, a game controller, a joystick, and / or any other suitable device for receiving action requests and transmitting action requests to the console 310. In some embodiments, the I / O interface 315 includes an IMU 340 that captures calibration data indicating an estimated current position of the I / O interface 315 relative to the initial position of the I / O interface 315.

[0082] In operation, the I / O interface 315 receives action requests from the user and transmits these action requests to the console 310. In response to receiving the action request, the console 310 performs the corresponding action. For example, in response to receiving the action request, the console 310 can configure the I / O interface 315 to transmit tactile feedback to the user's arm. For example, the console 315 can configure the I / O interface 315 to deliver tactile feedback to the user when the action request is received. Additionally or alternatively, in response to receiving the action request, the console 310 can configure the I / O interface 315 to generate tactile feedback when the console 310 performs the action.

[0083] Console 310 provides content to NED 305 for processing based on information received from one or more of: DCA 320, NED 305, and I / O interface 315. Figure 3 As shown, the console 310 includes an application memory 355, a tracking module 360, and an engine 365. In some embodiments, the console 310 may have a Figure 3 The modules and / or components described herein may be more, less, or different than those described herein. Similarly, the functionality described further below may be combined with Figure 3 The described methods are distributed among the components of console 310 in different ways.

[0084] Application memory 355 stores one or more applications executed by console 310. An application is a set of instructions that, when executed by a processor, performs a specific set of functions (such as generating content for presentation to a user). For example, an application may generate content in response to receiving input from a user (e.g., via movement of NED 305 when a user moves his / her head, via I / O interface 315, etc.). Examples of applications include: gaming applications, conferencing applications, video playback applications, or other suitable applications.

[0085] The tracking module 360 ​​calibrates the NED system 300 using one or more calibration parameters. The tracking module 360 ​​may also adjust one or more calibration parameters to reduce errors in determining the position and / or orientation of the NED 305 or the I / O interface 315. For example, the tracking module 360 ​​may send the calibration parameters to the DCA 320 in order to adjust the focus of the DCA 320. As a result, the DCA 320 may more accurately determine the position of the structured light elements reflected from objects in the environment. The tracking module 360 ​​may also analyze the sensor data generated by the IMU 340 in determining the various calibration parameters to modify. In addition, in some embodiments, if the NED 305 loses tracking of the user's eyes, the tracking module 360 ​​may recalibrate some or all components in the NED system 300. For example, if the DCA 320 loses sight of at least a threshold number of structured light elements projected onto the user's eyes, the tracking module 360 ​​may transmit the calibration parameters to the zoom module 350 in order to reestablish eye tracking.

[0086] The tracking module 360 ​​tracks the movement of the NED 305 and / or the I / O interface 315 using information from the DCA 320, one or more position sensors 335, the IMU 340, or some combination thereof. For example, the tracking module 360 ​​may determine a reference position of the NED 305 based on a map of the local area of ​​the NED 305. The tracking module 360 ​​may generate the map based on information received from the NED 305 itself. The tracking module 360 ​​may also utilize sensor data from the IMU 340 and / or depth data from the DCA 320 to determine a reference position of the NED 305 and / or the I / O interface 315. In various embodiments, the tracking module 360 ​​generates an estimate and / or prediction for a subsequent position of the NED 305 and / or the I / O interface 315. The tracking module 360 ​​may transmit the predicted subsequent position to the engine 365.

[0087] The engine 365 generates a three-dimensional map of an area around the NED 305 (i.e., a “local area”) based on information received from the NED 305. In some embodiments, the engine 365 determines depth information for the three-dimensional map of the local area based on depth data received from the DCA 320 (e.g., depth information of objects in the local area). In some embodiments, the engine 365 calculates the depth and / or position of the NED 305 by using the depth data generated by the DCA 320. Specifically, the engine 365 may implement various techniques for calculating the depth and / or position of the NED 305, such as stereo-based techniques, structured light illumination techniques, time-of-flight techniques, etc. In various embodiments, the engine 365 updates a model of the local area using the depth data received from the DCA 320, and generates and / or modifies media content based in part on the updated model.

[0088] The engine 365 also executes applications within the NED system 300 and receives position information, acceleration information, velocity information, predicted future position, or some combination thereof of the NED 305 from the tracking module 360. Based on the received information, the engine 365 determines various forms of media content to be transmitted to the NED 305 for presentation to the user. For example, if the received information indicates that the user has looked to the left, the engine 365 generates media content for the NED 305, which reflects the user's movement in a virtual environment or in an environment that enhances a local area with additional media content. Thus, the engine 365 can generate and / or modify media content (e.g., video and / or audio content) for presentation to the user. The engine 365 can also transmit the media content to the NED 305. In addition, in response to receiving an action request from the I / O interface 315, the engine 365 can perform an action within an application executing on the console 310. The engine 365 can also provide feedback when performing an action. For example, engine 365 may configure NED 305 to generate visual and / or audio feedback and / or configure I / O interface 315 to generate tactile feedback to the user.

[0089] In some embodiments, based on eye tracking information received from the eye tracking system 345 (e.g., the orientation of the user's eyes), the engine 365 determines the resolution of media content provided to the NED 305 for presentation to the user on the display 325. The engine 365 can adjust the resolution of the visual content provided to the NED 305 by configuring the display 325 to perform foveated rendering of the visual content based at least in part on the direction of the user's gaze received from the eye tracking system 345. The engine 365 provides content to the NED 305 that has a high resolution in a central area of ​​the display 325 where the user is looking, and a low resolution in other areas, thereby reducing power consumption of the NED 305. In addition, using foveated rendering reduces the number of computational cycles used in drawing the visual content without compromising the quality of the user's visual experience. In some embodiments, the engine 365 can further use the eye tracking information to adjust the focus of image light emitted from the display 325 so as to reduce vergence-accommodation conflict.

[0090] High-resolution LCD display

[0091] Figure 4 4 is a schematic diagram illustrating a display system 400 according to various embodiments. As shown, the display system 400 includes a green liquid crystal display 402, red and blue liquid crystal displays 404, a combiner 406, and a collimating optical device 408. In an embodiment, the display system 400 can be used to provide image light to one eye or both eyes of a user. If the display system 400 only provides image light to one eye of the user, a duplicate display system can be used for the other eye of the user.

[0092] In some embodiments, the green display 402 has a higher resolution than the red and blue displays 404. Since the human eye responds most to photons of green light, the effective resolution of the display system 400 can be the effective resolution of the higher resolution green display 402. For example, if the green display 402 has a sufficiently high resolution, the user will be able to read small text well even if the red and blue displays 404 have lower resolutions. In some embodiments, the display system 400 can provide a higher display resolution than a conventional color liquid crystal display (LCD) by employing a sub-pixel aperture ratio of 1:2 or 1:1, which is less than the sub-pixel aperture ratio of 1:3 used in conventional color LCDs, as described below in conjunction with Figure 5-Figure 7Discussed in more detail. In addition, greater transmittance can be achieved in the display system 400 relative to a conventional color LCD. In this regard, the green display 402 is a monochrome display that may include a green light emitting diode (LED), or a quantum dot (QD) layer embedded in a backlight unit (BLU) to control the color of the BLU, which is contrary to the color filters used in conventional color LCDs, and the panel transmittance can be reduced by four times. For example, the green display 402 may include a glass display panel and a display BLU including a green LED, or an embedded QD layer that converts light emitted by the LED into green light. In contrast to the green display 402, in some embodiments, the red and blue displays 404 may be color LCDs including color filters.

[0093] In operation, the red and blue colors needed to produce an image are emitted by red and blue displays 404, while the green needed to produce the same image is emitted by green display 402. Combiner 406 combines the light emitted by the two displays 402 and 402, and the combined light passes through collimating optics 408 toward the viewer's eye 410.

[0094] As shown, the green display 402 and the red and blue displays 404 are positioned perpendicular to each other. In addition, the combiner 406 is positioned so that light emitted by the green display 402 passes through the combiner 406, while light emitted by the red and blue displays 404 is reflected by the combiner 406. As a result, the light emitted by the green display 402 is combined with the light emitted by the red and blue displays 404. In an alternative embodiment, the positions of the green display and the red and blue displays can be reversed, and the combiner can be used to reflect the light emitted by the green display and pass the light emitted by the red and blue displays.

[0095] Combiner 406 may include any (multiple) optical elements suitable for combining light emitted by green display 402 with light emitted by red and blue displays 404. In some embodiments, combiner 406 is a dichroic element that selectively transmits light within a range of colors, including the colors output by green display 402, while reflecting light of other colors, including the colors output by red and blue displays 404. Examples of such dichroic elements include dichroic beam splitters, dichroic mirrors, dichroic reflectors, and dichroic filters. It should be understood that some dichroic elements are smaller and / or lighter than other dichroic elements, which is beneficial for artificial reality systems such as HMDs.

[0096] In other embodiments, the combiner 406 may be a polarization-based combiner, assuming that the collimating optics 408 are not polarization-sensitive. It should be understood that LCDs such as the green display 402 and the red and blue displays 404 typically emit polarized light. In some embodiments, the green display 402 and the red and blue displays 404 emit light with different polarizations. In this case, the combiner 406 may be a polarization-based combiner that selectively transmits light having the polarization of the light emitted by the green display 402 while reflecting light having the polarization of the light emitted by the red and blue displays 404 (or vice versa if the positions of the green display and the red and blue displays are reversed and a different polarization-based combiner is used). Examples of such polarization-based combiners include reflective polarizers and polarizing beam splitters. It should be understood that some polarization-based combiners are smaller and / or lighter than other combiners, which is beneficial for artificial reality systems such as HMDs.

[0097] Collimating optics 408 may include any (multiple) optical elements suitable for collimating light passing through collimating optics 408. In an augmented reality system, light may be collimated so that the displayed image appears to be at "infinity" or very far away. In some embodiments, a pancake lens may be used as collimating optics 408. The back focal length of some pancake lenses may be relatively short, requiring the red and blue display 404 to be separated into two displays, as shown below in conjunction with Figure 7-Figure 8 In addition, polarization-based combiners cannot be used with polarization-sensitive pancake lenses. In other embodiments, a Fresnel lens can be used as collimating optics 408, as described below in conjunction with Figure 9-10 It will be appreciated that some collimating optics are smaller and / or lighter than other collimating optics, which can be beneficial for artificial reality systems such as HMDs.

[0098] Figure 5is a schematic diagram showing a pixel geometry 500 used in a conventional color LCD according to the prior art. In the pixel geometry 500, each pixel includes three sub-pixels for red, green and blue. As shown, pixel 502 includes a red sub-pixel 5041, a blue sub-pixel 5042 and a green sub-pixel 5043. Each sub-pixel 504 (referred to individually and collectively herein as sub-pixels 504) has an aperture ratio of 1:3, which means that the height of the sub-pixel 504 is three times the width of the sub-pixel 504. Such sub-pixels 504 are sometimes also referred to as "stripes". Existing manufacturing technology allows the width and height of LCD sub-pixels (or pixels) to be as small as 8 microns. Therefore, the size of each sub-pixel 504 can be as small as 8×24 microns, and the size of each pixel (e.g., pixel 502) including three sub-pixels 504 can be as small as 24×24 microns. Due to this size limitation, the resolution of conventional color LCDs is not high enough for some artificial reality systems.

[0099] Figure 6 It is shown that various embodiments can be used Figure 4 Schematic diagram of pixel geometry 600 in display system 400. In pixel geometry 600, each pixel includes a red sub-pixel and a blue sub-pixel from red and blue displays 404, and two sub-pixels from green display 402. As shown, sub-pixels 602 (referred to as sub-pixels 602 individually and collectively as sub-pixels 602 in this article) from red and blue displays 404 alternate between red and blue. In addition, each red or blue sub-pixel 602 from red and blue displays 404 corresponds to a green sub-pixel 604 (referred to as green sub-pixel 604 individually and collectively as green sub-pixel 904 in this article) from green display 402. For example, pixel 501 includes a red sub-pixel 6041, a blue sub-pixel 6042, and two corresponding green sub-pixels 6021 and 6022.

[0100] It should be noted that the green display 402 providing green sub-pixels 604 has a higher resolution than the red and blue display 404 providing red and blue sub-pixels 602 because each green sub-pixel 604 is a pixel of the green display 402, while pairs of red and blue sub-pixels 604 form pixels in the red and blue displays 404. However, if a sub-pixel aperture ratio of 1:3 is used, as in the above combination Figure 5 In the described pixel geometry 500, the display resolution will only be improved in the horizontal direction. In some embodiments, different sub-pixel aperture ratios are also used to improve the display resolution in the vertical direction.

[0101] As shown, each sub-pixel 602 and 604 in pixel geometry 600 has an aperture ratio of 1:2, as opposed to the 1:3 sub-pixel aperture ratio used in conventional color LCDs. Because existing manufacturing technology allows sub-pixels (or pixels) to have widths and heights as small as 8 microns, each sub-pixel 602 and 604 has a minimum size of 8×16 microns, and each pixel (e.g., pixel 601) including two sub-pixels 602 and two sub-pixels 604 has a minimum size of 16×16 microns. The smaller possible sizes of the sub-pixels (and pixels) in display system 400 relative to the sub-pixels (and pixels) of conventional color LCDs enable higher display resolutions, including greater resolutions than can be achieved with conventional color LCDs.

[0102] Figure 7 It is shown that various embodiments can be used Figure 4 Schematic diagram of an alternative pixel geometry 700 in a display system of FIG. Similar to pixel geometry 600, each pixel in pixel geometry 700 includes a red subpixel and a blue subpixel from red and blue displays 404, and a corresponding green subpixel from green display 402. As shown, subpixels 704 from red and blue displays 404 (individually referred to as subpixels 704 and collectively referred to as subpixels 704 herein) alternate between red and blue, and each red or blue subpixel 704 from the red and blue displays 404 corresponds to a green subpixel 702 of the green display 402 (individually referred to as green subpixels 702 and collectively referred to as green subpixels 702 herein). Exemplarily, pixel 701 includes a red subpixel 7041, a blue subpixel 7042, and two corresponding green subpixels 7021 and 7022.

[0103] As shown, each sub-pixel 702 and 704 has an aperture ratio of 1:1. As described above, existing manufacturing techniques allow the width and height of sub-pixels (or pixels) to be as small as 8 microns. Therefore, the size of each sub-pixel 702 and 704 can be as small as 8×8 microns, and the size of each pixel (e.g., pixel 701) including two sub-pixels 702 and two sub-pixels 704 can be as small as 8×16 microns. In some embodiments, pixels of this size can provide a resolution of 1-1.5 arc minutes. The smaller possible size of such sub-pixels (and pixels) relative to the sub-pixels (and pixels) of conventional color LCDs enables higher display resolutions, including resolutions greater than those achievable with conventional color LCDs.

[0104] Although pixel geometry is primarily described herein with respect to pixels and sub-pixels in the form of rectangles or squares, in other embodiments, pixels and sub-pixels may be any technically feasible shape, such as hexagonal or circular.

[0105] Figure 8 8 is a schematic diagram showing a display system 800 including two red and blue displays according to various embodiments. As shown, the display system 800 includes a green display 802, two red and blue displays 804 and 806 positioned relative to each other, two combiners 808 and 810 that combine light emitted by the green display 802 with light emitted by the red and blue displays 804 and 806, respectively, and a pancake lens 812 that collimates the combined light.

[0106] Green display 802 is similar to the above combination Figure 4 The green display 402 is described. The red and blue displays 804 and 806 are similar to the above combined Figure 4 The red and blue displays 404 are described above, except that each of the red and blue displays 804 and 806 is configured to display only the red and blue from half of the image. For example, the red and blue display 804 can display the left half of the image, while the red and blue display 806 can display the right half of the image. In combination with the above Figure 4 Two combiners 808 and 810 similar to the combiner 406 described above are used to combine light from the green display 802 and the red and blue displays 804 and 806, respectively. Figure 4 , combiners 808 and 810 cannot be polarization based because pancake lens 812 is polarization sensitive. In an alternative embodiment, the green display may be split into two halves, rather than red and blue displays.

[0107] As described above, if the pancake lens 812 has a relatively short back focal length, two red and blue displays 804 and 806 (or two green displays) are required. If a pancake lens (or other collimating optics) with a longer focal length is used, only one red and blue display (e.g., red and blue display 404) may be required. On the other hand, the display system 800 including the pancake lens 812 can be more compact and lighter than some other display systems.

[0108] Fig. 9 The following are more detailed descriptions of various embodiments. Figure 8 The display system 800. Specifically, Fig. 9 It is shown how combiners 808 and 810 combine light emitted by the red and blue displays 802 and 806 with light emitted by the green display 802 , and how the combined light is collimated by a pancake lens 812 .

[0109] Fig.101 is a schematic diagram showing a display system 1000 including a Fresnel lens according to various embodiments. As shown in the figure, the display system 1000 includes a green display 1002, red and blue displays 1004, a beam splitter 1006, and a Fresnel lens 1008. The green display 1002 and the red and blue displays 1004 are similar to the above combined Figure 4 A green display 402 and red and blue displays 404 are depicted.

[0110] Fresnel lens 1008 has a Figure 8 The pancake lens 812 depicted has a longer back focal length. Therefore, the red and blue display 1004 is not split into two displays. However, the display system 1000 may be less compact and heavier than the display system 800 including the pancake lens 812.

[0111] In some embodiments, in combination with the above Figure 4 The beam splitter similar to the combiner 406 described above can be a dichroic element or a polarizing beam splitter. Figure 4 In the depicted display system 400, a beam splitter 1006 transmits light emitted by the green display 1002 and reflects light emitted by the red and blue display 1004 (or vice versa if the positions of the green display and the red and blue displays are reversed and different beam splitters are used), thereby combining the light emitted by the two displays 1002 and 1004. The combined light from the green display 1002 and the red and blue display 1004 then passes through a Fresnel lens 1008 which collimates the combined light.

[0112] Fig.11 The following are more detailed descriptions of various embodiments. Fig.10 The green display 1102, the beam splitter 1106 and the Fresnel lens 1108. Specifically, Fig.11 It is shown how beam splitter 1106 combines light emitted by the red and blue displays 802 and 806 with light emitted by the green display 802 , and how the combined light is collimated by pancake lens 812 .

[0113] Fig.12 1 is a schematic diagram showing a display system 1200 including a crossed dichroic prism according to various embodiments. As shown, the display system 1200 includes a green display 1202, a red display 1204, a blue display 1206, a crossed dichroic prism 1208 (also referred to herein as an "X-cube"), and a collimating optical device 1210. The green display 1202 and the collimating optical device 1210 are similar to the above combined Figure 4Green display 402 and collimating optics 408 are depicted. Red display 1204 and blue display 1206 are each monochrome displays, which may include color LEDs or QD films embedded in the BLU to control the color of the emitted light, as opposed to color filters, thereby allowing higher transmittance relative to conventional color LCD displays that include color filters. In addition, pixel geometries that enable pixel sizes as small as 8×8 microns may be used, as described below in conjunction with Fig.13 However, the display system 1200 may require a large back focal length and thus be more complex than the above combined Figure 4 , 8 The display systems 400, 800, and 1000 described in connection with FIGS. 10 and 10 are less compact and heavier.

[0114] As shown, the green display 1202, the red display 1204, and the blue display 1206 are located on different sides of the X-cube 1208. In operation, the red, green, and blue colors required to produce an image are emitted by the red 1204, green 1202, and blue 1206 color displays, respectively. As shown, the light emitted by the green display 1202 passes through the X-cube 1208, while the light emitted by the red display 1204 and the blue display 1206 are reflected by the X-cube 1208. Therefore, the X-cube 1208 combines the light emitted by the green display 1202 with the light emitted by the red display 1204. The combined light then passes through the collimating optical device 1210 toward the observer's eye 1212.

[0115] Fig.13 is a diagram showing the Fig.12 Schematic diagram of a pixel geometry 1300 of a display system of FIG. As shown, each pixel in the pixel geometry 1300 includes a red subpixel 1302 from a red display 1204, a blue subpixel 1306 from a blue display 1202, and a green subpixel 1302 from a green display 1202. The red subpixel 1302, the blue subpixel 1304, and the green subpixel 1306 are referred to herein individually as red subpixels 1302, blue subpixels 1304, and green subpixels 1306, respectively, and collectively as red subpixels 1302, blue subpixels 1304, and green subpixels 1306, respectively. Illustratively, a pixel 1301 includes a red subpixel 13021, and corresponding blue subpixels 13042 and green subpixels 13061.

[0116] As shown, each of the red, blue, and green sub-pixels 1302, 1304, and 1306 has an aperture ratio of 1:1. As described above, existing manufacturing techniques allow the width and height of the sub-pixels (or pixels) to be as small as 8 microns. Therefore, the size of each of the red, blue, and green sub-pixels 1302, 1304, and 1306 can be as small as 8×8 microns, and the size of each pixel (e.g., pixel 1301) including one of the red sub-pixels 1302, one of the blue sub-pixels 1304, and one of the green sub-pixels 1306 can be as small as 8×8 microns. Relative to the sub-pixels (and pixels) of conventional color LCDs, the smaller possible sizes of such sub-pixels (and pixels) enable higher display resolutions, including resolutions greater than those achievable with conventional color LCDs.

[0117] Although red, blue, and green sub-pixels 1302, 1304, and 1306 are shown as squares for purposes of illustration, in other embodiments, the sub-pixels and pixels may be any technically feasible shape, such as hexagonal or circular.

[0118] Fig.14 is a flow chart of method steps for displaying an image according to various embodiments. Figure 4 and Figure 6-Figure 13 The method steps are described with reference to a system, but those skilled in the art will appreciate that in other embodiments, any system can be configured to implement the method steps in any order.

[0119] As shown, method 1400 begins at step 1402, where green light associated with an image is emitted via an LCD. The LCD may be, for example, a combination of the above Figure 4 , Figure 8 , Fig.10 and Fig.12 One of the green displays 402, 802, 1002, or 1202 described. More generally, any LCD that emits light in a wavelength range corresponding to human perception of green can be used. As described above, in some embodiments, such an LCD can include a green LED or a QD layer embedded in the BLU instead of a color filter.

[0120] At step 1404, red and blue light associated with the image are emitted via at least one other LCD. The at least one other LCD may be, for example, a combination of Figure 4 , Figure 8 ,and Fig.10 In the above described red and blue displays 404, 804 and 806, or 1004, or in combination Fig.12In the above description, the red display 1204 and the blue display 1206 are shown. More generally, any (multiple) LCDs that emit light in the wavelength range corresponding to red and blue may be used. As described above, in some embodiments, such (multiple) LCDs may use red and blue color filters, or if the display system includes a red LCD and a separate blue LCD, red and blue LEDs may be used.

[0121] At step 1406, the green light and the red and blue lights are combined via at least one combiner element to generate a combined light. The at least one combiner element may include, for example, a dichroic element or (a plurality of) polarization-based combiners, such as combining Figure 4 , Figure 8 , Fig.10 ,and Fig.12 Combiner 406, combiners 808 and 810, beam splitter 1006, or X-cube 1208 are depicted.

[0122] At step 1408, the combined light passes through a collimating optical element. The collimating optical element may be, for example, a combination of Figure 4 , Figure 8 , Fig.10 ,and Fig.12 One of collimating optics 408, pancake lens 812, Fresnel lens 1008, or collimating optics 1210 is depicted.

[0123] Although primarily described herein with respect to opaque displays, in alternative embodiments one or more transparent displays may be used, such as a transparent green display and / or transparent red and blue displays. In this case, the light emitted by the transparent displays may be combined by positioning one display in front of the other display without the need for a combiner element.

[0124] In summary, embodiments disclosed herein relate to high-resolution liquid crystal displays. In some embodiments, light emitted by a high-resolution green liquid crystal display is combined with light emitted by at least one lower-resolution red and blue liquid crystal display via a combiner. (Multiple) red and blue displays may include a single display or two displays located on opposite sides of the combiner. The combiner may be a dichroic element or a polarization-based combiner. The combined light from the green display and (multiple) red and blue displays is directed toward the observer's eyes through collimating optics (such as a pancake lens or a Fresnel lens). Since the human eye is most sensitive to green light, the use of a higher-resolution green display allows for improved resolution relative to conventional color LCDs. In particular, some embodiments employ a sub-pixel aperture ratio of 1:2 or 1:1, which allows the sub-pixels and pixels of the display system to be smaller than those in a conventional color LCD. In addition, relative to conventional color LCDs that rely on color filters, a green display including a green LED or a QD layer embedded in a BLU can be used to achieve higher transmittance of green light.

[0125] One advantage of the display system disclosed herein is that a higher display resolution can be achieved relative to a conventional color LCD. In addition, the display system disclosed herein can be brighter than a conventional color LCD, especially for green light. Therefore, the display system disclosed herein can be more suitable for some artificial reality systems (such as HMDs) than conventional color LCDs. These technical advantages represent one or more technical advances relative to prior art methods.

[0126] 1. In some embodiments, a display system includes: a first display configured to emit light within a first wavelength range; a second display configured to emit light within at least one other wavelength range; a combiner element; and a collimating optical element.

[0127] 2. A display system according to clause 1, wherein the first wavelength range is associated with the color green and the at least one other wavelength range is associated with the colors red and blue.

[0128] 3. A display system according to clause 1 or 2, wherein the first display comprises a green light emitting diode (LED).

[0129] 4. A display system according to any one of clauses 1 to 3, wherein the first display is positioned so that the light within the first wavelength range is transmitted by the combiner element, and the second display is positioned so that the light within the at least one other wavelength range is reflected by the combiner element.

[0130] 5. A display system according to any of clauses 1 to 4, wherein the combiner element is one of a polarization-based combiner or a dichroic element.

[0131] 6. A display system according to any of clauses 1 to 5, wherein the collimating optical element is a pancake lens.

[0132] 7. A display system according to any one of clauses 1 to 6, further comprising a third display configured to emit light within the at least one other wavelength range, wherein the second display and the third display are each configured to display half of an image.

[0133] 8. A display system according to any of clauses 1 to 7, wherein the collimating optical element is a Fresnel lens.

[0134] 9. A display system according to any one of clauses 1 to 8, wherein the first wavelength range is associated with green, the at least one other wavelength range is associated with red, and the display system further comprises a third display configured to emit light within a wavelength range associated with blue.

[0135] 10. A display system according to any of clauses 1 to 9, wherein the combiner element is a crossed dichroic prism.

[0136] 11. A display system according to any of clauses 1 to 10, wherein pixels in the display system comprise sub-pixels having a 1:2 aperture ratio or a 1:1 aperture ratio.

[0137] 12. A display system according to any one of clauses 1 to 11, wherein the first display and the second display are liquid crystal displays (LCDs).

[0138] 13. In some embodiments, a head-mounted display (HMD) includes a display system comprising a first display configured to emit light within a first wavelength range, a second display configured to emit light within at least one other wavelength range, a combiner element, and a collimating optical element.

[0139] 14. The HMD of clause 13, wherein the first wavelength range is associated with the color green, the at least one other wavelength range is associated with the color red and blue, and the first display has a higher resolution than the second display.

[0140] 15. The HMD of clause 13 or 14, wherein the combiner element is one of: a dichroic element, a crossed dichroic prism, or a polarization-based combiner.

[0141] 16. A HMD according to any of clauses 13 to 15, wherein the collimating optical element is one of a pancake lens or a Fresnel lens.

[0142] 17. An HMD according to any of clauses 13 to 16, wherein pixels in the display system comprise sub-pixels having a 1:2 aperture ratio or a 1:1 aperture ratio.

[0143] 18. In some embodiments, a method includes: emitting light within a first wavelength range via a first display; emitting light within at least one other wavelength range via a second display; combining the light within the first wavelength range and the light within the at least one other wavelength range via a combiner element to generate combined light; and passing the combined light through a collimating optical element.

[0144] 19. The method according to clause 18, wherein the first wavelength range is associated with the color green and the at least one other wavelength range is associated with the colors red and blue.

[0145] 20. A method according to clause 18 or 19, wherein combining the light in the first wavelength range and the light in the at least one other wavelength range comprises: transmitting the light in the first wavelength range via the combiner element, and reflecting the light in the at least one other wavelength range via the combiner element.

[0146] Any and all combinations of any claim elements recited in any claim and / or any elements described in this application are within the intended scope of the disclosure and protection in any manner.

[0147] The foregoing description of the embodiments of the present disclosure has been presented for illustrative purposes; it is not intended to be exhaustive or to limit the disclosure to the precise form disclosed. Those skilled in the relevant art will appreciate that many modifications and variations are possible based on the above disclosure.

[0148] Certain portions of this specification describe embodiments of the present disclosure in terms of algorithms and symbolic representations of operations on information. Technicians in the field of data processing often use these algorithmic descriptions and representations to effectively convey the essence of their work to other technicians in the field. Although these operations are described functionally, computationally, or logically, these operations are understood to be implemented by computer programs or equivalent circuits, microcodes, etc. In addition, without loss of generality, it sometimes proves convenient to refer to these operational arrangements as modules. The described operations and their associated modules can be implemented in software, firmware, hardware, or any combination thereof.

[0149] Any steps, operations or processes described herein may be performed or implemented using one or more hardware or software modules, either alone or in combination with other devices. In one embodiment, the software module is implemented using a computer program product, which includes a computer-readable medium containing computer program code, which can be executed by a computer processor to perform any or all of the steps, operations or processes described.

[0150] Embodiments of the present disclosure may also relate to an apparatus for performing the operations herein. The apparatus may be specially constructed for the desired purpose, and / or it may include a general-purpose computing device selectively activated or reconfigured by a computer program stored in a computer. Such a computer program may be stored in a non-transitory, tangible computer-readable storage medium or any type of medium suitable for storing electronic instructions, which may be coupled to a computer system bus. In addition, any computing system mentioned in this specification may include a single processor, or may be an architecture that employs multiple processor designs to increase computing power.

[0151] Embodiments of the present disclosure may also relate to products produced by the computing process described herein. Such products may include information produced by the computing process, wherein the information is stored on a non-transitory tangible computer-readable storage medium, and may include any embodiment of a computer program product or other data combination described herein.

[0152] Finally, the language used in the specification is selected primarily for readability and instructional purposes, and may not be selected to describe or limit the subject matter of the present invention. Therefore, the scope of the present disclosure is not limited by this detailed description, but by any claims filed based on the application herein. Therefore, the disclosure of the embodiments is intended to illustrate, but not to limit, the scope of the disclosure set forth in the following claims.

[0153] The description of the various embodiments has been presented for purposes of illustration, but is not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope of the claims.

[0154] The various aspects of the present embodiment can be implemented as a system, method or computer program product. Therefore, the various aspects of the present disclosure can take the form of a complete hardware embodiment, a complete software embodiment (including firmware, resident software, microcode, etc.) or a combination of software and hardware embodiments, which are generally referred to as "modules" or "systems" in this article. In addition, the various aspects of the present disclosure can take the form of a computer program product implemented in one or more computer-readable media (on which a computer-readable program code is implemented).

[0155] Any combination of one or more computer-readable media may be used. A computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared or semiconductor system, apparatus or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer-readable storage media would include the following: an electrical connection with one or more conductors, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer-readable storage medium may be any tangible medium that is capable of containing or storing a program used by or in conjunction with an instruction execution system, apparatus or device.

[0156] Aspects of the present disclosure are described above with reference to the flowchart illustrations and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments of the present disclosure. It should be understood that each frame of the flowchart illustration and / or block diagram and the combination of frames in the flowchart illustration and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer or other programmable data processing device to produce a machine. When these instructions are executed via a processor of a computer or other programmable data processing device, these instructions can implement specific functions / actions in one or more frames of the flowchart and / or block diagram. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, an application-specific processor or a field programmable gate array.

[0157] The flowcharts and block diagrams in the figure illustrate the possible implementation architecture, functions and operations of the system, method and computer program product according to various embodiments of the present disclosure. In this regard, each box in the flowchart or block diagram may represent a module, segment or portion of the code, which includes one or more executable instructions for implementing a specific logical function. It should also be noted that in some replaceable implementations, the functions indicated in the box may not occur in the order indicated in the figure. For example, depending on the functions involved, two boxes shown in succession may actually be executed substantially simultaneously, or the boxes may sometimes be executed in the opposite order. It should also be noted that each box in the block diagram and / or flowchart description, and the combination of boxes in the block diagram and / or flowchart description can be implemented by a dedicated hardware-based system that performs a specific function or action, or a combination of dedicated hardware and computer instructions.

[0158] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope of the disclosure is determined by the following claims.

Claims

1. A display system, comprising: a first display configured to emit light within a first wavelength range associated with the green color; a second display configured to emit light in at least one other wavelength range, the second display having a lower resolution than the first display; Combiner element; as well as Collimating optics, Wherein one or both of the first display or the second display includes one or both of the following: LCD display, or A quantum dot layer embedded in the backlight unit.

2. The display system of claim 1, wherein the at least one other wavelength range is associated with red and blue. 3 . The display system of claim 2 , wherein the first display comprises a green light emitting diode or a quantum dot layer embedded in a backlight unit.

4. The display system according to claim 1, wherein: the first display is positioned such that the light in the first wavelength range is transmitted by the combiner element; and The second display is positioned such that the light in the at least one other wavelength range is reflected by the combiner element.

5. The display system of claim 1, wherein the combiner element is one of a polarization-based combiner or a dichroic element.

6. The display system of claim 1, wherein the collimating optical element is a pancake lens.

7. The display system according to claim 6, further comprising: a third display configured to emit light within said at least one other wavelength range, The second display and the third display are each configured to display half of an image.

8. The display system of claim 1, wherein the collimating optical element is a Fresnel lens.

9. The display system of claim 1 , wherein the first wavelength range is associated with the color green, the at least one other wavelength range is associated with the color red, and the display system further comprises a third display configured to emit light within a wavelength range associated with the color blue.

10. The display system of claim 9, wherein the combiner element is a crossed dichroic prism.

11. The display system of claim 1, wherein pixels in the display system include sub-pixels having a 1:2 aperture ratio or a 1:1 aperture ratio.

12. The display system of claim 1, wherein the first display and the second display are liquid crystal displays (LCDs).

13. A head mounted display (HMD), comprising: A display system, the display system comprising: a first display configured to emit light within a first wavelength range associated with the green color, a second display configured to emit light in at least one other wavelength range, the second display having a lower resolution than the first display, combiner element, and Collimating optics, Wherein one or both of the first display or the second display includes one or both of the following: LCD display, or A quantum dot layer embedded in the backlight unit.

14. The HMD of claim 13, wherein: The at least one other wavelength range is associated with the colors red and blue.

15. The HMD of claim 13, wherein the combiner element is one of: a dichroic element, a crossed dichroic prism, or a polarization-based combiner.

16. The HMD of claim 13, wherein the collimating optical element is one of a pancake lens or a Fresnel lens. 17 . The HMD of claim 13 , wherein pixels in the display system include sub-pixels having a 1:2 aperture ratio or a 1:1 aperture ratio.

18. A method of displaying, comprising: emitting light within a first wavelength range associated with the green color via a first display; emitting light in at least one other wavelength range via a second display, the second display having a lower resolution than the first display; combining the light in the first wavelength range with the light in the at least one other wavelength range via a combiner element to generate combined light; and passing the combined light through a collimating optical element, Wherein one or both of the first display or the second display includes one or both of the following: LCD display, or A quantum dot layer embedded in the backlight unit.

19. The method of claim 18, wherein the at least one other wavelength range is associated with red and blue.

20. The method of claim 18, wherein combining the light in the first wavelength range with the light in the at least one other wavelength range comprises: transmitting the light within the first wavelength range through the combiner element; as well as The light in the at least one other wavelength range is reflected via the combiner element.

Images