Abstract: An optical combiner in a display system of a mixed-reality head-mounted display (HMD) device comprises a lens of birefringent material and a ferroelectric liquid crystal (FLC) modulator that are adapted for use with a reflective waveguide to provide multiple different focal planes on which holograms of virtual-world objects (i.e., virtual images) are displayed. The birefringent lens has two orthogonal refractive indices, ordinary and extraordinary, depending on the polarization state of the incident light. Depending on the rotation of the polarization axis by the FLC modulator, the incoming light to the birefringent lens is focused either at a distance corresponding to the ordinary refractive index or the extraordinary refractive index. Virtual image light leaving the birefringent lens is in-coupled to a see-through reflective waveguide which is configured to form an exit pupil for the optical combiner to enable an HMD device user to view the virtual images from the source.

Abstract: The present disclosure describes near-eye display systems including an array of projectors and a one-dimensional exit pupil expander. The array of projectors can be arranged along a first dimension and can output image light towards an input coupler within a waveguide that provides one-dimensional exit pupil expansion. In some implementations, arrays of monochromatic projectors are implemented and arranged in offset columns. The input coupler in-couples the image light from the array of projectors into a TIR path within the waveguide. Different optical elements, including diffractive and reflective optics, may be implemented as the input coupler. The image light travels within the waveguide until it interacts with an output coupler. Upon interaction with the output coupler, the image light is expanded in a second dimension transverse to the first dimension and is coupled out of the waveguide.

Abstract: Examples are disclosed that relate to using an array of hot mirrors in an eye-imaging system. One example provides a head-mounted display system, comprising a frame, an eye-imaging camera supported on the frame, a switchable hot mirror array comprising a plurality of switchable hot mirrors configured to direct light reflecting from an eye toward the eye-imaging camera, and a controller configured to control switching of a reflectivity of each of the plurality of switchable hot mirrors.

Abstract: Variable-focus lenses are arranged as a lens pair that work on opposite sides of a see-through optical combiner used in a mixed-reality head-mounted display (HMD) device. An eye-side variable-focus lens is configured as a negative lens over an eyebox of the see-through optical combiner to enable virtual-world objects to be set at a close distance. The negative lens is compensated by its conjugate using a real-world-side variable-focus lens configured as a positive lens to provide an unperturbed see-through experience. For non-presbyopes, the powers of the lenses are perfectly offset. For presbyopes, the lens powers is mismatched at times to provide simultaneous views of both virtual-world and real-world objects on the display in sharp focus. Responsively an eye tracker indicating that the user is engaged in close viewing, optical power is added to the real-world-side lens to push close real-world objects optically farther away into sharp focus for the presbyopic user.

Abstract: Examples are disclosed that relate to using an array of hot mirrors in an eye-imaging system. One example provides a head-mounted display system, comprising a frame, an eye-imaging camera supported on the frame, a switchable hot mirror array comprising a plurality of switchable hot mirrors configured to direct light reflecting from an eye toward the eye-imaging camera, and a controller configured to control switching of a reflectivity of each of the plurality of switchable hot mirrors.

Abstract: A display engine adapted for use in a head-mounted display (HMD) device includes a reflective liquid crystal on silicon (LCoS) spatial light modulator (SLM) that is illuminated using a backlight illumination module and a pair of optical prisms providing a total internal reflection (TIR) function. In an illustrative mixed-reality embodiment, the TIR prism pair guides light to the LCoS SLM from the backlight illumination module and projects virtual images reflected from the LCoS SLM, through projection optics, to a diffractive waveguide combiner for viewing by an HMD user.

Abstract: Variable-focus lenses are arranged as a lens pair that work on opposite sides of a see-through optical combiner used in a mixed-reality head-mounted display (HMD) device. An eye-side variable-focus lens is configured as a negative lens over an eyebox of the see-through optical combiner to enable virtual-world objects to be set at a close distance. The negative lens is compensated by its conjugate using a real-world-side variable-focus lens configured as a positive lens to provide for an unperturbed see-through experience. For non-presbyopes, the powers of the lenses are perfectly offset. For presbyopes, the lens powers may be mismatched at times to provide simultaneous views of both virtual-world and real-world objects on the display in sharp focus. Responsively an eye tracker indicating that the user is engaged in close viewing, optical power is added to the real-world-side lens to push close real-world objects optically farther away and into sharp focus for the presbyopic user.

Abstract: Slanted surface relief gratings for use in an optical display system in an HMD device are replicated in a manufacturing process that utilizes non-contact optical proximity recording into a specialized photo-sensitive resin that is disposed over a waveguide substrate. The recording process comprises selective resin exposure to ultraviolet light through a mask to spatially record grating structures by interferential exposure and polymerization. Subsequent resin development evacuates unexposed resin down to the waveguide substrate to remove flat surfaces, referred to as a bias layer, that remain in the grating trenches after exposure. The resin development reduces Fresnel reflections that could otherwise be induced at the media interface between the bias layer and the waveguide substrate. Fresnel reflections may cause a loss of diffraction efficiency and thereby reduce the field of view that may be guided by the SRGs in the optical display system.

Abstract: The invention is directed to pharmaceutical compositions such as tablets that exhibit delayed release properties when administered as either whole or half tablets. The invention is also directed to delayed release tablets comprising deferiprone for oral administration, for which twice daily administration is bioequivalent to the same daily dose of an immediate release tablet administered thrice daily. The invention is also directed to methods of making and using the same.

Abstract: Examples are disclosed that relate to a compact optical systems comprising SLMs. One example provides a projection system comprising an illumination stage including a light emitting diode (LED) array. The LED array comprises a plurality of red LEDs, a plurality of green LEDs, and a plurality of blue LEDs. The illumination stage further comprises an illumination stage optical system configured to control an angular extent of light emitted by the LED array and homogenize the light emitted by the LED array. The projection system further comprises an image forming stage configured to form an image from light output by the illumination stage, the image forming stage comprising a spatial light modulator (SLM) configured to spatially modulate the light output by the illumination stage to form an image, and one or more projection optics configured to project the image formed by the spatial light modulator.

Abstract: A display engine adapted for use in a head-mounted display (HMD) device includes a reflective liquid crystal on silicon (LCoS) spatial light modulator (SLM) that is illuminated using a backlight illumination module and a pair of optical prisms providing a total internal reflection (TIR) function. In an illustrative mixed-reality embodiment, the TIR prism pair guides light to the LCoS SLM from the backlight illumination module and projects virtual images reflected from the LCoS SLM, through projection optics, to a diffractive waveguide combiner for viewing by an HMD user.

Abstract: An optical combiner in a display system of a mixed-reality head-mounted display (HMD) device comprises a lens of birefringent material and a ferroelectric liquid crystal (FLC) modulator that are adapted for use with a reflective waveguide to provide multiple different focal planes on which holograms of virtual-world objects (i.e., virtual images) are displayed. The birefringent lens has two orthogonal refractive indices, ordinary and extraordinary, depending on the polarization state of the incident light. Depending on the rotation of the polarization axis by the FLC modulator, the incoming light to the birefringent lens is focused either at a distance corresponding to the ordinary refractive index or the extraordinary refractive index. Virtual image light leaving the birefringent lens is in-coupled to a see-through reflective waveguide which is configured to form an exit pupil for the optical combiner to enable an HMD device user to view the virtual images from the source.

Abstract: The invention is directed to pharmaceutical compositions such as tablets that exhibit delayed release properties when administered as either whole or half tablets. The invention is also directed to delayed release tablets comprising deferiprone for oral administration, for which twice daily administration is bioequivalent to the same daily dose of an immediate release tablet administered thrice daily. The invention is also directed to methods of making and using the same.

Abstract: Variable-focus lenses are arranged as a lens pair that work on opposite sides of a see-through optical combiner used in a mixed-reality head-mounted display (HMD) device. An eye-side variable-focus lens is configured as a negative lens over an eyebox of the see-through optical combiner to enable virtual-world objects to be set at a close distance. The negative lens is compensated by its conjugate using a real-world-side variable-focus lens configured as a positive lens to provide for an unperturbed see-through experience. For non-presbyopes, the powers of the lenses are perfectly offset. For presbyopes, the lens powers may be mismatched at times to provide simultaneous views of both virtual-world and real-world objects on the display in sharp focus. Responsively an eye tracker indicating that the user is engaged in close viewing, optical power is added to the real-world-side lens to push close real-world objects optically farther away and into sharp focus for the presbyopic user.

Abstract: A head-mounted display device including one or more position sensors and a processor. The processor may receive a rendered image of a current frame. The processor may receive position data from the one or more position sensors and determine an updated device pose based on the position data. The processor may apply a first spatial correction to color information in pixels of the rendered image at least in part by reprojecting the rendered image based on the updated device pose. The head-mounted display device may further include a display configured to apply a second spatial correction to the color information in the pixels of the rendered image at least in part by applying wobulation to the reprojected rendered image to thereby generate a sequence of wobulated pixel subframes for the current frame. The display may display the current frame by displaying the sequence of wobulated pixel subframes.

Abstract: Examples are provided related to using multiplexed diffractive elements to improve eye tracking systems. One example provides a head-mounted display device comprising a see-through display system comprising a transparent combiner having an array of diffractive elements, and an eye tracking system comprising one or more light sources configured to direct light toward an eyebox of the see-through display system, and also comprising an eye tracking camera. The array of diffractive elements comprises a plurality of multiplexed diffractive elements configured to direct images of a respective plurality of different perspectives of the eyebox toward the eye tracking camera.

Abstract: Examples are disclosed relating to tunable attenuation of incident light using a switchable grating. One example provides an optical attenuator comprising a switchable grating configured to diffract light within a wavelength band at a diffraction angle. The optical attenuator further comprises an electrode pair configured to apply a voltage across the switchable grating to tune a proportion of incident light diffracted at the diffraction angle, and an optical dump to receive the proportion of incident light diffracted.

Abstract: An augmented reality display device includes a near-eye display configured to present imagery to a user eye. A camera is configured to capture light from a real-world environment and produce output useable to contribute to the imagery presented to the user eye via the near-eye display. The camera includes an aperture configured to receive the light from the real-world environment and an image sensor configured to respond to the light received from the real-world environment by generating sensor output signals useable to produce images on the near-eye display depicting the real-world environment. One or more optical elements provide an optical path for light from the aperture to the image sensor, the optical path having a length that is within a threshold of a distance between the user eye and the aperture of the camera.

Abstract: This document relates to an optical device using waveguide that can enable propagation of large field of view images by use of metasurfaces, without the necessity of increasing the reflective index associated with the waveguide. An optical assembly can generate a compressed image corresponding to a wide field of view in order to ensure that the image can propagate through the waveguide according to TIR limits of the waveguide. The compressed image can be provided to a standard grating in-coupler, and can then be expanded by a metasurface out-coupler of the optical device to reproduce the wide field of view.

Abstract: The invention is directed to pharmaceutical compositions such as tablets that exhibit delayed release properties when administered as either whole or half tablets. The invention is also directed to delayed release tablets comprising deferiprone for oral administration, for which twice daily administration is bioequivalent to the same daily dose of an immediate release tablet administered thrice daily. The invention is also directed to methods of making and using the same.