Abstract: Described herein are accelerometers, apparatus and systems incorporating accelerometers, and techniques for electrostatically adjusting a stiffness of a spring system in an accelerometer. Embodiments featuring resonant and/or quasi-static accelerometers are described. In certain embodiments, an accelerometer is a microelectromechanical systems (MEMS) device including a proof mass, an anchor, a spring attached to the proof mass, a sense electrode, and a tuning electrode. The spring and the proof mass form a spring system suspended from the anchor. The sense electrode is configured to generate a signal indicating movement of the proof mass based on application of a first signal. The tuning electrode is configured to receive an electrostatic tuning signal, the electrostatic tuning signal being separate from the first signal and providing a negative contribution to an overall stiffness of the spring system. The electrostatic tuning signal can be used to adjust the stiffness based on a measured acceleration.

Abstract: Disclosed herein includes a system, a method, and a device for rendering an image through adaptive reprojection. A first reprojection can be performed to generate a portion of a first image of a first view of a virtual space at a first rate. An amount of change from the first view to a second view of the virtual space can be determined. A portion of a second image of the second view of the virtual space can be determined to generate through a second reprojection. The second reprojection can be performed at a second rate to the portion of the second image according to the amount of change from the first view to the second view of the virtual space.

Abstract: In one embodiment, a method includes, by one or more computing systems, receiving, from a client system, an input in a multi-turn message thread, parsing the input to identify a plurality of hypothesis dialog states associated with the input, generating a plurality of functions corresponding to the plurality of hypothesis dialog states, calculating a plurality of probability scores for the plurality of functions, respectively, based on a prior dialog state associated with the message thread and a current user context, wherein each probability score represents a likelihood that the respective function is associated with an intended dialog state, and storing the plurality of functions if each of the probability scores is below a threshold probability score, wherein the plurality of functions is stored as a hierarchical set of functions that is used as the prior dialog state in response to a next input in the message thread.

Abstract: A head mounted display (HMD) includes an electronic display, an optical element, and a light sensor. The electronic display is configured to generate a pixel pattern of display light and the optical element is disposed to pass the display light to a user of the HMD. The light sensor is disposed proximate to the optical element to generate light measurements in response to the pixel pattern. The light measurements are representative of a lateral position of the optical element with respect to the electronic display.

Abstract: A method includes receiving an image of a real environment using a camera worn by a user, and determining a portion of the image that comprises an object of interest. Based on the portion of the image that comprises the object of interest, a surface representing the object of interest is generated. Depth measurements of the real environment corresponding to the portion of the image comprising the object of interest are received and used to determine a depth of the surface representing the object of interest. The surface is posed in a coordinate system corresponding to the real environment based on the depth of the surface and a visibility of a virtual object is determined relative to the object of interest by comparing a model of the virtual object with the surface. The output image is generated based on the determined visibility of the virtual object.

Abstract: The disclosed system may include (1) a diffractive optical element (DOE) stack including one or more DOEs, where the DOE stack generates, in response to incoming light received at a first side of the DOE stack, structured light from a second side of the DOE stack opposite the first side, (2) a primary light source that emits the incoming light toward the first side of the DOE stack, and (3) at least one photodetector that detects light emitted from an edge of each of at least one of the DOEs of the DOE stack, where the edge is located between the first side and the second side of the DOE stack. Various other methods and systems are also disclosed.

Abstract: A wearable device and system for detecting data generated by a user's contact with a surface and using that data to determine that a user contacted the surface and, in some examples, the location of the contact. The location of the contact may then be used by another device, such as an artificial reality headset, to select a user interface element, activate a function or perform a task in an artificial reality environment, or execute another type of function typically performed in response to an input to a user interface. In one example, the wearable device includes an ultrasound transmitter (Tx) and an ultrasound receiver (Rx). In some embodiments, the wearable device may also include a processing element capable of processing the signals detected or received by the receiver to determine that a contact occurred.

Abstract: In one embodiment, a computing system may determine a quantization range having a first quantization endpoint and a second quantization endpoint. While fixing the second quantization endpoint to an initial value determined based on the color range, one of a plurality of first candidate values for the first quantization endpoint is selected based on a plurality of corresponding first quantization errors. While fixing the first quantization endpoint to the selected first candidate value, one of a plurality of second candidate values for the second quantization endpoint is selected based on a plurality of corresponding second quantization errors. The computing system may define quantization levels corresponding to the bit depth using the quantization range defined by the first quantization endpoint and the second quantization endpoint, and then encode the one or more color components of the pixel region using the quantization levels.

Abstract: In one embodiment, a method includes receiving playback statuses from one or more second client computing devices that are in a synchronous presentation session with a first client computing device. Content presented on the first client computing device and the one or more second client computing devices may be determined to be out of synchronization. A plurality of synchronization options for synchronization of the content may be displayed on the first client computing device. The plurality of synchronization options may be based on the playback statuses associated with the first client computing device and the one or more second client computing devices. A particular synchronization option may be selected from the plurality of synchronization options. The content on the first client computing device may be synchronized with the one or more second client computing devices based on the particular synchronization option.

Abstract: In one embodiment, a method includes generating a visual interaction tool that moves and extends in a three-dimensional artificial-reality environment according to hand and arm movements of a user. It may be detected that the visual interaction tool intersects a predefined region associated with a virtual item of a first type in the AR environment. The visual interaction tool may attach to the first virtual item. A first operating mode for the visual interaction tool may be selected based on the first type of the first virtual item. The first operating mode may be selected from multiple operating modes for the visual interaction tool. A first input from the user may be received while the visual interaction tool is attached to the first virtual item. First operations with the first virtual item may be performed according to the first operating mode and the first input.

Abstract: The disclosed systems and methods are generally directed to interpreting neuromuscular signals. The system includes (A) a plurality of neuromuscular sensors that detect a plurality of neuromuscular signals from a user and (B) at least one multiplexer in communication with the plurality of neuromuscular sensors and that is capable of dynamically adjusting neuromuscular sensor processing based on neuromuscular signal characteristics. A computer processor is programmed to (i) receive a set of neuromuscular signals from the plurality of neuromuscular sensors, (ii) determine, via a real-time system, at least one signal characteristic included in a neuromuscular signal, where the neuromuscular signal is associated with a first neuromuscular sensor included in the plurality of neuromuscular sensors; and (iii) dynamically reconfigure the processing of neuromuscular signals from the plurality of neuromuscular sensors based on an output from the multiplexer.

Abstract: An artificial reality system is described that renders, presents, and controls user interface elements within an artificial reality environment, and performs actions in response to one or more detected gestures of the user. In one example, an artificial reality system comprises an image capture device configured to capture image data representative of a physical environment; a head-mounted display (HMD) configured to output artificial reality content; a gesture detector configured to identify, from the image data, a gesture comprising a motion of two fingers from a hand to form a pinching configuration and a subsequent pulling motion while in the pinching configuration; a user interface (UI) engine configured to generate a UI input element in response to identifying the gesture; and a rendering engine configured to render the UI input element as an overlay to at least some of the artificial reality content.

Abstract: A housing assembly for mounting a first lens and a second lens includes a first lens holder. The first lens holder includes a ring-shaped structure configured to mount the first lens. The housing assembly also includes a second lens holder including a cup-shaped structure. The cup-shaped structure includes an upper portion configured to mount the first lens holder, and a lower portion configured to mount the second lens.

Abstract: Disclosed herein are related to a system and a method of reducing contention in accessing a wireless link. In one aspect, a first device includes a transceiver configured to communicate with a second device via a wireless link. In one aspect, the first device includes a processor configured to determine that a type of content to be transferred between the first device and the second device through the wireless link. In one aspect, the processor is configured to modify one or more parameters for the first device to access the wireless link, from a first set of values to a second set of values, in response to determining that the type of content is artificial reality. In one aspect, the processor is configured to cause the transceiver to access the wireless link using the second set of values.

Abstract: An imaging device for imaging of a local area surrounding the imaging device. The imaging device includes a lens assembly, a filtering element and a detector. The lens assembly is configured to receive light from a local area surrounding the imaging device and to direct at least a portion of the received light to the detector. The filtering element is placed in the imaging device within the lens assembly such that light is incident at a surface of the filtering element within a range of angles determined by a design range of angles at which the filtering element is designed to filter light. The detector is configured to capture image(s) of the local area including the filtered light. The imaging device can be integrated into a depth camera assembly for determining depth information of object(s) in the local area based on the captured image(s).

Abstract: A display device including a laser-based light engine is disclosed. Optical interference effects due to the coherent nature of a laser light source are mitigated by shortening a coherence length of the laser source. The coherence length shortening is achieved by at least one of the following: providing a multiple longitudinal mode laser source, pulsing a laser source to achieve spectral broadening, or providing multi-emitter laser source(s) with emission wavelength varying from emitter to emitter.

Abstract: The disclosed method may include receiving neuromuscular activity data over a first time series from a first sensor on a wearable device donned by a user receiving ground truth data over a second time series from a second sensor that indicates a body part state of a body part of the user, generating one or more training datasets by time-shifting at least a portion of the neuromuscular activity data over the first time series relative to the second time series, to associate the neuromuscular activity data with at least a portion of the ground truth data, and training one or more inferential models based on the one or more training datasets. Various other related methods and systems are also disclosed.

Abstract: Disclosed herein are related to systems and methods for providing inputs through a virtual keyboard with an adaptive language model. In one approach, one or more processors determine whether a user intended to provide semantically meaningful characters or not, when providing a hand motion or a hand pose with respect to a virtual keyboard. The virtual keyboard may be located on a surface without physical keys. In one approach, the one or more processors determine an input to the virtual keyboard based on the hand motion or the hand pose. In one approach, the one or more processors determine weight of a language model according to the determined user intention. In one approach, the one or more processors modify the detected input according to the determined weight of the language model.

Abstract: A pick-up head assembly comprises a body of a liquid crystalline elastomer (LCE) that undergoes a reversible expansion when exposed to a first frequency of light and contracts when exposed to a second frequency of light. Selective portions of the LCE in the pick-up head assembly are irradiated with the first frequency to cause an expansion in the selective portions. The adhesive forces of the expanded portions of the LCE are used to pick-up semiconductor devices from a first substrate. The semiconductor devices are placed on a second substrate by exposing the expanded portions of the LCE to the second frequency of light, causing the expanded portions to contract.

Abstract: A near eye display (NED) includes multiple PBP optical elements combined with one or more C-plates to improve optical angular performance. The PBP optical elements may be configured for beam steering or for focusing light to a point. A C-plate may reduce or eliminate an undesirable polarization phase shift introduced by the PBP optical elements to angular, off-axis light. Birefringence of the PBP optical elements produces such a polarization phase shift. A C-plate provides an additional polarization phase shift that is opposite to the extra polarization phase shift by the PBP optical elements. Thus, the additional polarization phase shift by the C-plate at least partially reduces the phase shift by the PBP element.

Abstract: A head mounted display (HMD) includes a field curvature corrected (FC) display to mitigate field curvature in an image that is output to a user's eyes. The FC display includes elements that generate the image light and elements to mitigate field curvature from the image light. The FC display may include a display panel with lenses, a display panel with a reflective polarizer and reflective surface, or other optical elements. The FC display may include a pancake lens configuration including a polarized display with a quarter wave plate, a reflective mirror, and a polarization reflective mirror.

Abstract: Techniques disclosed herein relate to modifying refractive index modulation in a holographic optical element, such as a holographic grating. According to certain embodiments, a holographic optical element or apodized grating includes a polymer layer comprising a first region characterized by a first refractive index and a second region characterized by a second refractive index. The holographic optical element or apodized grating includes a plurality of nanoparticles dispersed in the polymer layer. The nanoparticles have a higher concentration in either the first region or the second region. In some embodiments, the nanoparticles may be configured to increase the refractive index modulation. In some embodiments, the nanoparticles may be configured to apodize the grating by decreasing the refractive index modulation proximate to sides of the grating. The refractive index may be modulated by applying a monomer reservoir buffer layer to the polymer layer, either before or after hologram fabrication.

Abstract: A method for classifying a gesture made in proximity to a touch interface. A system receives data related to the position and/or movement of hand. The data is delimited by identifying a variable length window of touch frames. The variable length window of touch frames is selected to include touch frames indicative of feature data. The variable length window of touch frames is classified based upon classifications learned by the classifying module to identify gestures.

Abstract: Embodiments relate to a display device including an active display area with pixels arranged in rows and columns, where a focus area of the active display area is operated in a progressive scanning manner and a non-focus area of the active display area is operated in an interlaced scanning manner. The active display area is driven by a gate driver circuit that supplies gate signals the pixels. First stages of the gate driver circuit are coupled to first rows of the pixels that are in the focus area and output first gate signals in the progressive scanning manner. Second stages of the gate driver circuit are coupled to second rows of the pixels that are in the non-focus area and output second gate signals in the interlaced scanning manner.

Abstract: A haptic device including a magnet, a rigid and conductive material arranged with respect to the magnet so as to create a gap between the magnet and the rigid and conductive material is disclosed. The haptic device is configured such that a magnetic field is generated in the gap by the magnet. The haptic device also includes a plurality of coils each connected to a respective one of a plurality of protruding elements where each of the plurality of coils are configured to be positioned within the gap. Each of the plurality of protruding elements are configured to produce a respective contact with an object when the respective coil is energized. In some embodiments, the object is a hand of a user.

Abstract: The disclosed radar system may include a radar mechanism comprising a transmitter and at least one receiver. The radar system may also include a signal generator that generates a frequency-modulated radar signal. In addition, the radar system may include a delay mechanism that (1) receives the frequency-modulated radar signal from the signal generator and (2) after a certain period of delay, passes the frequency-modulated radar signal to the transmitter to be transmitted to a transponder located on a wearable artificial reality device. The radar system may also include a processing device that (1) receives the frequency-modulated radar signal from the signal generator, (2) detects a signal returned to the receiver from the transponder, and (3) calculates a distance between the transponder and the receiver based at least in part on an analysis of the signal returned from the transponder and the frequency-modulated radar signal received from the signal generator.

Abstract: In one embodiment, a method for eye-tracking comprises capturing images of a user using one or more cameras, the captured images of the user depicting at least an eye of the user, storing the captured images of the user in a storage device, reading, from the storage device, a down-sampled version of the captured images of the user, detecting one or more first segments in the down-sampled version of the captured images by processing the down-sampled version of the captured images using a machine-learning model, the one or more first segments comprising features of the eye of the user, reading, from the storage device, one or more second segments in the captured images corresponding to the one or more first segments in the down-sampled version of the captured images, and computing a gaze of the user based on the one or more second segments in the captured images.

Abstract: In one embodiment, a method includes capturing, using one or more cameras implemented in a wearable device worn by a user, a first image depicting at least a part of a hand of the user holding a controller in an environment, identifying one or more features from the first image to estimate a pose of the hand of the user, estimating a first pose of the controller based on the pose of the hand of the user and an estimated grip that defines a relative pose between the hand of the user and the controller, receiving IMU data of the controller, and estimating a second pose of the controller by updating the first pose of the controller using the IMU data of the controller. The method utilizes multiple data sources to track the controller under various conditions of the environment to provide an accurate controller tracking consistently.

Abstract: An optical element includes a first boundary layer and a second boundary layer. A solution is disposed between the first boundary layer and the second boundary layer. The solution includes liquid crystals co-mingled with oblong photochromic dye molecules.

Abstract: A head mounted display (HMD) includes an electronic display configured to display a virtual scene to a user, an optics block, an eye tracking system, and a varifocal actuation that mechanically changes a distance between the optics block and the electronic display. The varifocal actuation block is configured to change a location of an image plane of the HMD and includes a motor, a power screw coupled to the actuating motor configured to turn responsive to actuation of the motor, and a nut sled on the power screw that is coupled to the electronic display. The nut sled is configured to move back and forth along a length of the power screw responsive to the power screw being turned by the motor that results in movement of the electronic display relative to the optics block.

Abstract: In one embodiment, a method includes creating, by a computing device, an inter process communication (IPC) channel for communication from a producer process to a consumer process. The IPC channel includes a message buffer mapped to a first virtual address space of a kernel of an operating system and to a second virtual address space of the consumer process in a user space of the operating system. A sender handle for the message buffer is sent to the producer process. The kernel receives a request, which includes the sender handle, to send a message from the producer process to the consumer process through the IPC channel. Responsive to a determination that the request is permitted, the kernel writes the message to the message buffer using the sender handle, such that message written in the message buffer is accessible to the consumer process through the second address space.

Abstract: Systems and methods for beamforming include a device including at least one of a head wearable display (HWD) or a console. The device establishes a first connection between an active HWD radio-frequency integrated circuit (RFIC) and an active console RFIC. The device compares a modulation and coding scheme (MCS) of the first connection to an MCS threshold. The device performs MCS measurements for a second connection of at least one of an idle HWD RFIC or an idle console RFIC, while the first connection is maintained, in response to the MCS not satisfying the MCS threshold. The device compares the MCS measurements of the second connection to the MCS threshold. The device switches to the second connection when at least one of the one or more MCS measurements satisfies the MCS threshold and/or above the MCS of the first connection.

Abstract: The technology disclosed relates to a machine learning based speech-to-text transcription intermediary which, from among multiple speech recognition engines, selects a speech recognition engine for accurately transcribing an audio channel based on sound and speech characteristics of the audio channel.

Abstract: The disclosed computer-implemented method may include applying, via a sound reproduction system, sound cancellation that reduces an amplitude of various sound signals. The method further includes identifying, among the sound signals, an external sound whose amplitude is to be reduced by the sound cancellation. The method then includes analyzing the identified external sound to determine whether the identified external sound is to be made audible to a user and, upon determining that the external sound is to be made audible to the user, the method includes modifying the sound cancellation so that the identified external sound is made audible to the user. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: A sensor assembly for determining one or more features of a local area is presented herein. The sensor assembly includes a plurality of stacked sensor layers. A first sensor layer of the plurality of stacked sensor layers located on top of the sensor assembly includes an array of pixels. The top sensor layer can be configured to capture one or more images of light reflected from one or more objects in the local area. The sensor assembly further includes one or more sensor layers located beneath the top sensor layer. The one or more sensor layers can be configured to process data related to the captured one or more images. A plurality of sensor assemblies can be integrated into an artificial reality system, e.g., a head-mounted display.

Abstract: A device includes one or more light guides. The device also includes a first in-coupling element configured to couple a first light having a first input field of view (“FOV”) into a first light guide, and a second in-coupling element configured to couple a second light having a second input FOV into a second light guide. The device also includes a first out-coupling element configured to couple the first light out of the first light guide as a first output light having a first output FOV, and a second out-coupling element configured to couple the second light out of the second light guide as a second output light having a second output FOV substantially non-overlapping with the first output FOV. A combination of the first output FOV and the second output FOV is larger than at least one of the first output FOV or the second output FOV.

Abstract: In one embodiment, a method includes determining a first time interval for rendering pixel values for a first portion of a display, where the first portion of the display is one of a plurality of portions of the display, accessing a representation of virtual objects in a virtual scene, and determining that the first time interval is insufficient for rendering pixel values for the first portion of the display based on the representation of virtual objects. The method further includes, for each of the portions of the display, determining a current viewpoint of a user, rendering, based on the current viewpoint of the user, pixel values for that portion of the display, and sending the rendered pixel values to be output by the display, where the rendered pixel values for the first portion of the display are rendered based on a simplified representation of virtual objects in the virtual scene.

Abstract: In one embodiment, a method includes receiving a user input comprising one or more words at a client system, wherein each word comprises one or more characters, inputting the words to a convolutional neural network (CNN) model stored on the client system, accessing a plurality of character-embeddings for a plurality of characters, respectively, from a data store of the client system, generating one or more word-embeddings for the one or more words, respectively, based on the accessed character-embeddings by processing the accessed character-embeddings with one or more convolutional layers and one or more gated linear units of the CNN model, determining one or more tasks corresponding to the user input for execution based on an analysis of the one or more word-embeddings by the CNN model, and providing an output responsive to the user input based on the execution of the one or more tasks at the client system.

Abstract: Disclosed herein are devices and methods related to an interface between a host processor and a wireless processor of a first device for maintaining an artificial reality session with a second device. In one aspect, the host processor is configured to provide data of the artificial reality session to the wireless processor, and the wireless processor is configured to transmit the data to the second device through a wireless medium. In one aspect, the host processor is configured to provide an indicator indicating an end of transmission of the data, to the wireless processor, to cause the wireless processor to transmit the indicator to the second device through the wireless medium, and to cause the host processor and the wireless processor to enter a sleep state in response to transmission of the indicator. The indicator may cause the second device to enter the sleep state.

Abstract: In one embodiment, a method includes accessing a plurality of points, wherein each point (1) corresponds to a spatial location associated with an observed feature of a physical environment and (2) is associated with a patch representing the observed feature, determining a density associated with each of the plurality of points based on the spatial locations of the plurality of points, scaling the patch associated with each of the plurality of points based on the density associated with the point, and reconstructing a scene of the physical environment based on at least the scaled patches.

Abstract: A system can include a device and a graphics processing unit (GPU). The device can be configured to receive a first image from one or more cameras corresponding to a first view and a second image from the one or more cameras corresponding to a second view. The GPU can include a motion estimator and configured to receive the first image and the second image and be configured to receive the first image and the second image. The motion estimator can be configured to determine first disparity offsets for the first image and second disparity offsets for the second image. The device can be configured to generate, for rendering 3D image using the first image and the second image, a first depth buffer for the first image derived from the first disparity offsets and a second depth buffer for the second image derived from the second disparity offsets.

Abstract: An audio system for providing content to a user. The system includes a first and a second transducer assembly of a plurality of transducer assemblies, an acoustic sensor, and a controller. The first transducer assembly couples to a portion of an auricle of the user's ear and vibrates over a first range of frequencies based on a first set of audio instructions. The vibration causes the portion of the ear to create a first range of acoustic pressure waves. The second transducer assembly is configured to vibrate over a second range of frequencies to produce a second range of acoustic pressure waves based on a second set of audio instructions. The acoustic sensor detects acoustic pressure waves at an entrance of the ear. The controller generates the audio instructions based on audio content to be provided to the user and the detected acoustic pressure waves from the acoustic sensor.

Abstract: The disclosed computer-implemented method may include (1) establishing a directional wireless link between a first computing device and a second computing device in a first direction, (2) exchanging, over the directional wireless link in the first direction, first data between the first computing device and the second computing device, (3) determining, via a sensor of the first computing device, a change to a position or an orientation of the first computing device, (4) redirecting, based on the change, the directional wireless link to a second direction, and (5) exchanging, over the directional wireless link in the second direction, second data between the first computing device and the second computing device. Various other methods and systems are also disclosed.

Abstract: A method of forming a nanovoided composite polymer includes forming a resin-containing layer over a substrate, the resin-containing layer including a polymer-forming phase and a sacrificial phase, curing the polymer-forming phase to form a polymer matrix containing the sacrificial phase, and removing the sacrificial phase selectively with respect to the polymer matrix to form a nanovoided composite polymer including the polymer matrix and nanovoids dispersed throughout the polymer matrix. The nanovoids may be randomly or regularly dispersed throughout the matrix. Various other methods, systems, apparatuses, and materials are also disclosed.

Abstract: Described herein are accelerometers, apparatus and systems incorporating accelerometers, and techniques for controlling sensing operations in an accelerometer. In certain embodiments, an accelerometer is a microelectromechanical systems (MEMS) device including a proof mass, an anchor, a spring between the proof mass and the anchor, a drive electrode, and a sense beam. The anchor is located in an opening defined by a body of the proof mass. The spring and the proof mass form a spring system suspended from the anchor. The sense beam is configured to oscillate at a particular resonance frequency that changes according to a force generated by movement of the proof mass in response to acceleration. In some embodiments, a support structure couples the anchor to the spring and operates as a stress decoupling area that prevents or limits propagation of stress from the anchor to the sense beam and the spring system.

Abstract: In one embodiment, a method includes, generating rays for casting into an artificial reality scene that includes one or more surfaces to determine whether the one or more surfaces are visible from a viewpoint. An origin and a trajectory of each ray are based on the viewpoint. The method includes applying a geometric transformation to the rays to modify their respective trajectory into the artificial reality scene. The geometric transformation is based on one or more distortion characteristics of a display system. The method includes determining, based on the modified trajectories of the rays, points of intersection of rays with the one or more surfaces in the artificial reality scene. The method includes providing, for display by the display system, color values generated based on the determined points of intersection.

Abstract: Techniques disclosed herein relate to micro light emitting diodes (micro-LEDs) for a display system. A display system includes an array of micro light emitting diodes (micro-LEDs), an array of output couplers optically coupled to the array of micro-LEDs and configured to extract light emitted by respective micro-LEDs in the array of micro-LEDs, a waveguide display, and display optics configured to couple the light emitted by the array of micro-LEDs and extracted by the array of output couplers into the waveguide display. Each output coupler in the array of output couplers is configured to direct a chief ray of the light emitted by a respective micro-LED in the array of micro-LEDs to a different respective direction.

Abstract: A device for illuminating a spatial light modulator includes a light source and an optical element. The light source is configured to provide illumination light. The optical element has a first surface, a second surface that is distinct from and non-parallel to the first surface, and a third surface that is distinct from and non-parallel to the first surface and the second surface. The optical element is configured to receive the illumination light at the first surface, propagate the illumination light via total internal reflection, and output the illumination light from the third surface. Also disclosed is a method performed by the device.

Abstract: Techniques for overcoating slanted structures and devices obtained using the techniques are disclosed. In some embodiments, a method of forming an overcoat layer on a surface-relief structure on a substrate includes receiving the substrate with the surface-relief structure. The surface-relief structure includes a plurality of ridges slanted with respect to the substrate, and a plurality of grooves each between two adjacent ridges. The method further includes depositing, in each cycle of a plurality of cycles, a uniform layer of an overcoat material on surfaces of the plurality of ridges and bottoms of the plurality of grooves. The deposited layers of the overcoat material and the plurality of ridges collectively form a light-coupling structure on the substrate. A surface of the overcoat layer is planar.

Abstract: Techniques disclosed herein relate to eye illumination for eye tracking in a near-eye display system. One example of an eye illumination system includes a substrate transparent to visible light and infrared light and configured to be placed in front of an eye of a user, and a shortwave-pass filter on a first surface of the substrate. The shortwave-pass filter includes regions configured to transmit visible light and reflect infrared light in ambient light, and a plurality of windows configured to transmit both visible light and infrared light in the ambient light.