Abstract: A multipass scanner usable e.g. in a near-eye display is disclosed. The multipass scanner scans a light beam angularly, forming an image in angular domain. The multipass scanner includes a light source, a tiltable reflector, and a multipass coupler that couples light emitted by the light source to the tiltable reflector, receives the reflected light and couples it back to the tiltable reflector to double the scanning angle. Then, the multipass coupler couples the light reflected at least twice from the tiltable reflector to an exit pupil of the scanner. A pupil-replicating waveguide disposed at the exit pupil of the scanner extends the image in angular domain. Multiple reflections of the light beam from the tiltable reflector enable one to increase the angular scanning range and associated field of view of the display without having to increase the angular scanning range of the tiltable reflector.

Abstract: A system for making a holographic medium for use in generating light patterns for eye tracking includes a light source configured to provide light and a beam splitter configured to separate the light into a first portion of the light and a second portion of the light that is spatially separated from the first portion of the light. The system also includes a first set of optical elements configured to transmit the first portion of the light for providing a first wide-field beam onto an optically recordable medium and a plurality of optical fibers configured to receive the second portion of the light and project a plurality of separate light patterns onto the optically recordable medium for forming the holographic medium.

Abstract: A system for making a holographic medium for use in generating light patterns for eye tracking includes a light source configured to provide light and a beam splitter configured to separate the light into a first portion of the light and a second portion of the light that is spatially separated from the first portion of the light. The system also includes a first set of optical elements configured to transmit the first portion of the light for providing a first wide-field beam onto an optically recordable medium, a second set of optical elements configured to transmit the second portion of the light for providing a second wide-field beam, and a plurality of parabolic reflectors optically coupled with the second set of optical elements and configured to receive the second wide-field beam and project a plurality of separate light patterns onto the optically recordable medium for forming the holographic medium.

Abstract: A display device includes a relay waveguide and a scanner. The scanner is configured to angularly scan image light for coupling into the waveguide, and includes a scanning reflector and a second reflector disposed between the scanning reflector and an input coupler of the waveguide. The scanning reflector has an aperture for the image light to propagate therethrough toward the second reflector. The second reflector is configured to reflect at least a portion of the image light received through the aperture back toward the scanning reflector and to transmit at least a portion of the image light reflected from the scanning reflector toward the input coupler. The arrangement enables a compact design of the display.

Abstract: An optical assembly includes a partial reflector that is optically coupled with a first polarization volume holographic element. The partial reflector is capable of receiving first light having a first circular polarization and transmitting a portion of the first light having a first circular polarization. The first polarization volume holographic element is configured to receive the first portion of the first light and reflect the first portion of the first light as second light having the first circular polarization. The partial reflector is capable of receiving the second light and reflecting a first portion of the second light as third light having a second circular polarization opposite to the first polarization. The first polarization volume holographic element is configured to receive the third light having the second circular polarization and transmit the third light having the second circular polarization.

Abstract: An astigmatism compensation optical assembly includes a first liquid crystal layer disposed between opposing substrates. The astigmatism compensation optical assembly also includes a first electrode pattern disposed on at least one substrate. The first electrode pattern includes a set of parallel conductors each having a length proportional to the longest dimension of the clear aperture of the liquid crystal lens, and the parallel conductors are configured to generate a voltage distribution within the liquid crystal layer that results in the liquid crystal layer exhibiting cylindrical focal power.

Abstract: Disclosed herein are techniques for eye illumination for eye position tracking. An illumination system includes a light source configured to emit a light beam in a first wavelength range, a beam splitter configured to split the light beam emitted by the light source into a plurality of light beams, a substrate configured to be placed in front of an eye of a user, and a plurality of reflectors located within the substrate. Each of the plurality of reflectors is configured to intercept one or more light beams from the plurality of light beams, reflect light in the one or more light beams from the plurality of light beams to the eye of the user, and transmit light in a second wavelength range different from the first wavelength range to the eye of the user. The substrate is transparent to both light in the first wavelength range and light in the second wavelength range.

Abstract: A multipass scanner usable e.g. in a near-eye display is disclosed. The multipass scanner scans a light beam angularly, forming an image in angular domain. The multipass scanner includes a light source, a tiltable reflector, and a multipass coupler that couples light emitted by the light source to the tiltable reflector, receives the reflected light and couples it back to the tiltable reflector to double the scanning angle. Then, the multipass coupler couples the light reflected at least twice from the tiltable reflector to an exit pupil of the scanner. A pupil-replicating waveguide disposed at the exit pupil of the scanner extends the image in angular domain. Multiple reflections of the light beam from the tiltable reflector enable one to increase the angular scanning range and associated field of view of the display without having to increase the angular scanning range of the tiltable reflector.

Abstract: An optical assembly includes a plurality of successive optical stages that are configured to transmit light at a variable overall optical power by configuring one or more stages of the successive optical stages. A respective optical stage of the successive optical stages includes an active optical element that is configurable to be in a first state at a first time and a second state at a second time that is distinct from the first time. The active optical element, in the first state, has a first respective optical power for light of a first polarization and a second respective optical power, that is different from the first respective optical power, for light of a second polarization that is orthogonal to the first polarization. The active optical element, in the second state, has a third optical power for light of the first polarization and light of the second polarization.

Abstract: A scanning projector for a display apparatus includes a first scanning reflector configured to steer a light beam in a first plane, a second scanning reflector configured to steer the light beam received from the first scanning reflector in a second plane, and beam relay optics configured to relay a first pupil defined at the first scanning reflector to a second pupil defined at the second scanning reflector, and to relay the second pupil to an output pupil of the scanning projector. The beam relay optics may include a concave reflector and a polarization beam splitter coupled to a scanning reflector in a triple pass configuration.

Abstract: A beam scanner of a projector-based near-eye display includes a prismatic element with a reflective polarizer and a quarter-wave waveplate (QWP). The beam-folding prismatic element receives a polarized light beam from a light source and couples the beam to a tiltable reflector, e.g. a 2D tiltable MEMS reflector, for angular scanning the beam. The light beam impinging onto the tiltable reflector is separated from the light beam reflected from the tiltable reflector by polarization. The polarization-based separation is achieved by causing the light beam to propagate through the QWP before and after impinging onto the tiltable reflector. Upon double propagation of the light beam through the QWP, the beam changes its polarization to an orthogonal polarization, which enables its separation from the impinging beam. The beam scanner may receive multiple light beams from multiple light sources. A projector and a near-eye display based on such beam scanners are also disclosed.

Abstract: A self-calibrating display can detect and compensate for binocular disparity or other visual imperfection of the display. The display includes a pair of projection units for projecting test light carrying test images through waveguides, which are normally used to carry images to left and right eyes of a user. A detection unit detects the test light propagated through the waveguides, and extracts the test images. Position of reference features in the detected test images may be used to determine binocular disparity, and luminance and color distribution across the test images may be used to determine the illumination and color uniformity of the images displayed to the user. After the visual defects have been detected, they may be reduced or compensated for by pre-emphasizing or shifting images to be displayed to the left and right eyes of the user.

Abstract: A head-mounted display device for providing augmented reality contents to a wearer includes a first light projector and a first Fresnel combiner. The first light projector is configured to project light for rendering images based at least on the augmented reality contents. The first Fresnel combiner is configured to combine the light from the first light projector and light from an outside of the head-mounted display device for providing an overlap of the rendered image and a real image that corresponds to the light from the outside of the head-mounted display device.

Abstract: An optical device includes a waveguide, a projector, a reflective display, and an in-coupler. The waveguide has a first side and an opposing second side. The projector is configured to project illumination light toward the first side of the waveguide. The reflective display is configured to receive the illumination light and to output image light toward the second side of the waveguide. The in-coupler is configured to receive the image light output by the reflective display and redirect a portion of the image light so that the portion of the image light undergoes total internal reflection inside the waveguide.

Abstract: A varifocal optical assembly includes a plurality of optical elements configured to transmit light in successive optical stages. Each respective optical stage of the successive optical stages includes at least one respective optical element of the plurality of optical elements and is configurable to be in one of a first state and a second state. The respective optical stage in the first state has a first respective optical power for light of a first polarization and a second respective optical power for light of a second polarization. The respective optical stage in the second state has a third optical power for light of the first polarization and a fourth optical power for light of the second polarization. The optical power of varifocal optical assembly is adjustable by changing the states of one or more of the successive optical stages.

Abstract: An optical assembly for projecting light output by a display includes an optical waveguide, a reflective optical element, and a in-coupler coupled with the optical waveguide. The reflective optical element is positioned to receive first light and to reflect the first light as second light. The in-coupler is positioned to receive the first light and transmit the first light toward the reflective optical element. The in-coupler is further positioned to receive the second light and redirect a first portion of the second light so that the first portion of the second light undergoes total internal reflection inside the optical waveguide. The reflective optical element includes a negative meniscus lens having a concave lens surface and a convex lens surface coupled with a reflective surface. The reflective optical element is positioned to focus the first light such that the second light is more collimated than the first light.

Abstract: An optical assembly includes a reflector and a volume Bragg grating (VBG). The VBG is positioned for: (i) transmitting light having a first polarization and incident upon the VBG at an incident angle that is within a first angular range, (ii) reflecting light having the first polarization and incident upon the VBG at an incident angle that is within a second angular range distinct from the first angular range, and (iii) transmitting light having a second polarization different from the first polarization. The optical assembly is configured to receive first light, having the first polarization, and reflect the first light at the reflector and at the VBG before the first light is output from the optical assembly. The optical assembly is configured to receive second light, having the second polarization, and output the second light from the optical assembly without undergoing reflection at either the reflector or the VBG.

Abstract: A system includes an eyewear device, and a neckband device. The neckband device includes a power source and a processor communicatively coupled to the eyewear device. The system includes a bracelet device, which includes at least one sensor configured to determine a position signal in response to movement of the user's hand, the bracelet device communicatively coupled to the processor. A display device is configured to present content to a user, and is also configured to couple to and be removable from the eyewear device.

Abstract: An astigmatism compensation optical assembly includes a first liquid crystal layer disposed between opposing substrates. The astigmatism compensation optical assembly also includes a first electrode pattern disposed on at least one substrate. The first electrode pattern includes a set of parallel conductors each having a length proportional to the longest dimension of the clear aperture of the liquid crystal lens, and the parallel conductors are configured to generate a voltage distribution within the liquid crystal layer that results in the liquid crystal layer exhibiting cylindrical focal power.

Abstract: A display device includes a frame, a display, an optical assembly, and a display-moving assembly connected to the display and the frame. The display-moving assembly is configured to move the display between multiple different positions, including a first position and a second position. When the display is in the first position, the display is configured to output image light in a first direction. The first direction is substantially parallel to an optical axis of the optical assembly. When the display is in the second position, the display is positioned away from the optical axis of the optical assembly.