Abstract: A waveguide display assembly comprises a waveguide, including an in-coupling grating configured to in-couple light of a first wavelength band emitted by a light source into the waveguide, and cause propagation of the light of the first wavelength band through the waveguide via total internal reflection. An out-coupling grating is configured to out-couple the light of the first wavelength band from the waveguide and toward a user eye. One or more diffractive gratings are disposed along an optical path between the in-coupling grating and the out-coupling grating, the one or more diffractive gratings configured to diffract light outside the first wavelength band out of the waveguide and away from the user eye.

Abstract: Reflectors comprising thin film dichroic coatings are located on various components of a waveguide-based optical combiner in a see-through display of a head-mounted display (HMD) device to reduce color cross-coupling in holographic images and reflect forward-projected holographic image light back to a user's eye. The dichroic coatings implement narrowband reflectors for each of one or more colors of an RGB (red, green, blue) color model over the angular range associated with the field of view (FOV) of the virtual portion of the see-through display. Utilization of the dichroic coatings can improve virtual display uniformity and lessen sharp edge defects by reducing cross-coupling and may also improve light security by reducing the forward-projected holographic image light that escapes from the HMD device.

Abstract: A waveguide display assembly comprises a waveguide, including an in-coupling grating configured to in-couple light of a first wavelength band emitted by a light source into the waveguide, and cause propagation of the light of the first wavelength band through the waveguide via total internal reflection. An out-coupling grating is configured to out-couple the light of the first wavelength band from the waveguide and toward a user eye. One or more diffractive gratings are disposed along an optical path between the in-coupling grating and the out-coupling grating, the one or more diffractive gratings configured to diffract light outside the first wavelength band out of the waveguide and away from the user eye.

Abstract: Reflectors comprising thin film dichroic coatings are located on various components of a waveguide-based optical combiner in a see-through display of a head-mounted display (HMD) device to reduce color cross-coupling in holographic images and reflect forward-projected holographic image light back to a user's eye. The dichroic coatings implement narrowband reflectors for each of one or more colors of an RGB (red, green, blue) color model over the angular range associated with the field of view (FOV) of the virtual portion of the see-through display. Utilization of the dichroic coatings can improve virtual display uniformity and lessen sharp edge defects by reducing cross-coupling and may also improve light security by reducing the forward-projected holographic image light that escapes from the HMD device.

Abstract: A method for setting a display white point comprises displaying images with a display including at least a first light source and a second light source. The first light source is configured to emit light having a first color and having a first temperature-dependent luminance change. The second light source is configured to emit light having a second color and having a second temperature-dependent luminance change. An internal display temperature is measured. Based on the internal display temperature being a first temperature, a first target white point is set to prioritize color accuracy. Based on the internal display temperature being a second temperature, greater than the first temperature, a second target white point is set to prioritize luminance output.

Abstract: A method for setting a display white point comprises displaying images with a display including at least a first light source and a second light source. The first light source is configured to emit light having a first color and having a first temperature-dependent luminance change. The second light source is configured to emit light having a second color and having a second temperature-dependent luminance change. An internal display temperature is measured. Based on the internal display temperature being a first temperature, a first target white point is set to prioritize color accuracy. Based on the internal display temperature being a second temperature, greater than the first temperature, a second target white point is set to prioritize luminance output.

Abstract: Examples are disclosed that relate to a display device. One example provides a display device comprising a projector and a pre-expander optic configured to replicate an exit pupil of the projector in at least a first direction, the pre-expander optic comprising a plurality of spectrally-selective pupil-replicating elements to form at least two exit pupils at different spatial locations, each exit pupil being for a different spectral band. The display device further comprises a waveguide comprising at least two incoupling pupils, each incoupling pupil configured to receive light from a corresponding exit pupil of the pre-expander optic, and the waveguide configured to replicate each corresponding exit pupil in at least a second direction and output the light received toward an eyebox.

Abstract: Examples are disclosed that relate to expanding an exit pupil of a display device via a curved waveguide. One example provides a curved waveguide, including an input coupler configured to couple light into the curved waveguide, a first reflective surface, a second reflective surface opposing the first reflective surface, and an output coupler configured to couple the light out of the curved waveguide. The curved waveguide also has a curvature in a direction transverse to an optical path between the input coupler and the output coupler, the curvature having a radius that varies along a direction extending between the input coupler and the output coupler.

Abstract: Examples are disclosed that relate to expanding an exit pupil of a display device via a curved waveguide. One example provides a curved waveguide, including an input coupler configured to couple light into the curved waveguide, a first reflective surface, a second reflective surface opposing the first reflective surface, and an output coupler configured to couple the light out of the curved waveguide. The curved waveguide also has a curvature in a direction transverse to an optical path between the input coupler and the output coupler, the curvature having a radius that varies along a direction extending between the input coupler and the output coupler.

Abstract: Aspects described herein generally relate to a waveguide and/or an associated display apparatus. The waveguide includes a plurality of optical input ports configured to receive optical light, at least one optical output port configured to output at least a modified portion of the optical light, and a plurality of transmission channels, each coupled to one of the plurality of optical input ports and configured to transmit the optical light from a respective optical input port to the at least one optical output port. The plurality of transmission channels are arranged to cause the optical light diffracted from at least a first one of the plurality of transmission channels to partially overlap, at the at least one optical output port, with the optical light diffracted from at least a second one of the plurality of transmission channels.

Abstract: A waveguide-based pupil relay for an optical system can comprise a light-transmissive substrate that includes a plurality of internally reflective surfaces to enable light rays of a plurality of different colors to propagate through the substrate by total internal reflection. The pupil relay can further include an input surface to input light rays of the plurality of different colors through an entry pupil of the optical waveguide, and an output surface to output light rays of the plurality of different colors from the substrate through an exit pupil of the optical waveguide. The pupil relay can have optical properties such that the entry pupil and exit pupil have substantially identical size and shape and such that the input light rays and output light rays have substantially identical chromatic properties.

Abstract: Examples are disclosed that relate to a display device. One example provides a display device comprising a projector and a pre-expander optic configured to replicate an exit pupil of the projector in at least a first direction, the pre-expander optic comprising a plurality of spectrally-selective pupil-replicating elements to form at least two exit pupils at different spatial locations, each exit pupil being for a different spectral band. The display device further comprises a waveguide comprising at least two incoupling pupils, each incoupling pupil configured to receive light from a corresponding exit pupil of the pre-expander optic, and the waveguide configured to replicate each corresponding exit pupil in at least a second direction and output the light received toward an eyebox.

Abstract: Aspects described herein generally relate to a waveguide and/or an associated display apparatus. The waveguide includes a plurality of optical input ports configured to receive optical light, at least one optical output port configured to output at least a modified portion of the optical light, and a plurality of transmission channels, each coupled to one of the plurality of optical input ports and configured to transmit the optical light from a respective optical input port to the at least one optical output port. The plurality of transmission channels are arranged to cause the optical light diffracted from at least a first one of the plurality of transmission channels to partially overlap, at the at least one optical output port, with the optical light diffracted from at least a second one of the plurality of transmission channels.

Abstract: A multi-chromatic optical waveguide for a near-eye display (NED) device includes reflective/refractive structures and periodic grating structures. Image incoupling and outcoupling can be done by reflective mirrors/facets, and image expansion can done by one or more even order expansion gratings. Wider field of view can be by achieved by splitting the field-of-view into multiple portions that propagate in different directions within the waveguide and then recombining those portions in the outcoupling region of the waveguide.

Abstract: Introduced here is a display device that comprises a light emitter and a diffractive optical element (DOE) that is optically coupled to receive light from the light emitter and to convey the light along an optical path. The DOE may have an input surface and an output surface parallel to the input surface, where the input surface and the output surface each have a central region and a peripheral region. The DOE further may have optical characteristics such that light exiting the DOE in the peripheral region of the output surface has greater brightness than light exiting the DOE in the central region of the output surface.

Abstract: A multi-chromatic optical waveguide for a near-eye display (NED) device includes reflective/refractive structures and periodic grating structures. Image incoupling and outcoupling can be done by reflective mirrors/facets, and image expansion can done by one or more even order expansion gratings. Wider field of view can be by achieved by splitting the field-of-view into multiple portions that propagate in different directions within the waveguide and then recombining those portions in the outcoupling region of the waveguide.

Abstract: Disclosed are an apparatus and method for reducing interference for a near-eye display device. The near-eye display device includes an imager, a spatial light modulator and a waveguide. The imager generates an image based on light from a coherent light source. The spatial light modulator modulates phases of a plurality of coherent light rays representing the image received from the imager. The waveguide receives and guides the light rays having varied phases such that light rays propagating within the waveguide are incoherent with each other.

Abstract: A waveguide configured for use with a near eye display (NED) device can include a light-transmissive substrate configured to propagate light rays through total internal reflection and a switchable diffractive optical element (DOE) on a surface of the substrate that is configured to input and/or output light rays to and/or from the substrate. According to some embodiments, the switchable DOE can include diffractive properties that vary across an area of the DOE. In some embodiments, the switchable DOE includes a surface relief diffraction grating (SRG) a surface of the substrate, a layer of liquid crystal material in contact with the SRG, a layer of conducting material in contact with the liquid crystal material configured to apply the voltage to the liquid crystal material, and a layer of insulating material over the layer of conducting material.

Abstract: Disclosed are an apparatus and method for reducing interference for a near-eye display device. The near-eye display device includes an imager, a spatial light modulator and a waveguide. The imager generates an image based on light from a coherent light source. The spatial light modulator modulates phases of a plurality of coherent light rays representing the image received from the imager. The waveguide receives and guides the light rays having varied phases such that light rays propagating within the waveguide are incoherent with each other.

Abstract: A waveguide configured for use with a near eye display (NED) device can include a light-transmissive substrate configured to propagate light rays through total internal reflection and a switchable diffractive optical element (DOE) on a surface of the substrate that is configured to input and/or output light rays to and/or from the substrate. According to some embodiments, the switchable DOE can include diffractive properties that vary across an area of the DOE. In some embodiments, the switchable DOE includes a surface relief diffraction grating (SRG) a surface of the substrate, a layer of liquid crystal material in contact with the SRG, a layer of conducting material in contact with the liquid crystal material configured to apply the voltage to the liquid crystal material, and a layer of insulating material over the layer of conducting material.