Abstract: An electronic device may include a display that produce images. The display may generate light for an optical system that redirects the light towards an eye box. The optical system may include a waveguide that propagates the light in a first direction towards the output coupler. The output coupler may couple the light out of the waveguide towards the eye box while inverting a parity of the light about the first direction. The coupler may include a first element such as a set of partial mirrors or diffractive gratings that redirects a first portion of the light in a second direction. The coupler may include a second element that redirects a second portion of the light in a third direction opposite the second direction. The first element may redirect the second portion and the second element may redirect the first portion towards the eye box.

Abstract: A static multiview display and method of static multiview display operation provide a static multiview image using diffractive gratings to that encode pixels of the static multiview image. The static multiview display includes a light guide configured to guide plurality of guided light beams and a light source configured to provide the guided light beam plurality having the different radial directions. The static multiview display further includes a plurality of diffraction gratings configured to provide different individual directional light beams from a portion of the radially directed guided light beams. The different individual directional light beams having different intensities and directions corresponding to and representing different view pixels of the static multiview image.

Abstract: An electronic device may have a waveguide, an input coupler that couples light into the waveguide, and an optical coupler that couples the light out of the waveguide. A medium may be layered onto the waveguide. The input coupler may include a first surface relief grating (SRG) and the optical coupler may include a second SRG in the medium. The first SRG may be a non-binary staircase SRG having ridges with multiple steps. The second SRG may be a binary SRG having troughs that extend to the height of the lowest steps of the first SRG. A reflective layer may fill the first SRG. Forming the input coupler using a staircase SRG may serve to maximize the in-coupling efficiency of the input coupler, thereby maximizing the efficiency with which the light is provided to an eye box.

Abstract: An electronic device may include a display that generates light for an optical system that redirects the light towards an eye box. The optical system may include a waveguide, a non-diffractive input coupler, a cross coupler, and an output coupler. The cross coupler may expand the light in a first direction. The cross coupler may perform an even number of diffractions on the light and may couple the light back into the waveguide at an angle suitable for total internal reflection. The output coupler may expand the light in a second direction while coupling the light out of the waveguide. The cross coupler may include surface relief gratings or holographic gratings embedded within the waveguide or formed in a separate substrate. The optical system may direct the light towards the eye box without chromatic dispersion and while supporting an expanded field of view and optical bandwidth.

Abstract: Multi-wavelength light is directed to an optic including a substrate and metasurface optical components deposited on a surface of the substrate. The metasurface optical components comprise a pattern of silicon dielectric resonators with nonperiodic gap distances between adjacent dielectric resonators. Incident light directed to the metasurface optical components is scattered and phase-shifted by the configuration of the gap distances and the widths and thicknesses of the dielectric resonators. Each dielectric resonator has a rectangular cross-section such that a first phase shift is imparted for a transverse-electric (TE) component of the incident light and a second phase shift is imparted for a transverse-magnetic (TM) component of the incident light.

Abstract: An electronic device may include a display that generates light for an optical system that redirects the light towards an eye box. The optical system may include a waveguide, a non-diffractive input coupler, a cross coupler, and an output coupler. The cross coupler may expand the light in a first direction. The cross coupler may perform an even number of diffractions on the light and may couple the light back into the waveguide at an angle suitable for total internal reflection. The output coupler may expand the light in a second direction while coupling the light out of the waveguide. The cross coupler may include surface relief gratings or holographic gratings embedded within the waveguide or formed in a separate substrate. The optical system may direct the light towards the eye box without chromatic dispersion and while supporting an expanded field of view and optical bandwidth.

Abstract: Multi-wavelength light is directed to an optic including a substrate and metasurface optical components deposited on a surface of the substrate. The metasurface optical components comprise a pattern of silicon dielectric resonators with nonperiodic gap distances between adjacent dielectric resonators. Incident light directed to the metasurface optical components is scattered and phase-shifted by the configuration of the gap distances and the widths and thicknesses of the dielectric resonators. Each dielectric resonator has a rectangular cross-section such that a first phase shift is imparted for a transverse-electric (TE) component of the incident light and a second phase shift is imparted for a transverse-magnetic (TM) component of the incident light.

Abstract: A display may include a waveguide. An input coupler may couple image light into the waveguide and an output coupler may couple the image light out of the waveguide. A surface relief grating on the waveguide may couple infrared light into the waveguide and may couple the infrared light out of the waveguide. The surface relief grating may additionally or alternatively couple reflected infrared light into the waveguide and out of the waveguide and towards an infrared sensor. The surface relief grating may also form a cross-coupler for the image light. The infrared sensor may gather infrared sensor data based on the reflected infrared light. Control circuitry may perform gaze tracking operations based on the infrared sensor data. The input and output couplers may also be formed from surface relief gratings or may include other optical components.

Abstract: An electronic device may have a display that provides image light to a waveguide. First and second liquid crystal lenses may be mounted to opposing surfaces of the waveguide. An coupler may couple the image light out of the waveguide through the first lens. The second lens may convey world light to the first lens. Control circuitry may control the first lens to apply a first optical power to the image light and the world light and may control the second lens to apply a second optical power to the world light that cancels out the first optical power. Each lens may include two layers of liquid crystal molecules having antiparallel pretilt angles. The pretilt angles and rubbing directions of the first lens may be antiparallel to corresponding pretilt angles and rubbing directions of the second lens about the waveguide.

Abstract: An electronic device may have a display that emits image light, a waveguide, and an input coupler that couples the image light into the waveguide. Beam splitter structures may be embedded within the waveguide. The beam splitter structures may partially reflect the image light multiple times and may serve to generate replicated beams of light that are coupled out of the waveguide by an output coupler. The beam splitter structures may replicate the beams across two dimensions to provide an eye box with uniform-intensity light from the display across its area. The beam splitter structures may include stacked partially reflective beam splitter layers, sandwiched transparent substrate layers having different indices of refraction, a thick volume hologram interposed between substrate layers, or combinations of these or other structures. The reflectivity of the beam splitter structures may vary discretely or continuously across the lateral area of the waveguide.

Abstract: Multi-wavelength light is directed to an optic including a substrate and achromatic metasurface optical components deposited on a surface of the substrate. The achromatic metasurface optical components comprise a pattern of dielectric resonators. The dielectric resonators have nonperiodic gap distances between adjacent dielectric resonators; and each dielectric resonator has a width, w, that is distinct from the width of other dielectric resonators. A plurality of wavelengths of interest selected from the wavelengths of the multi-wavelength light are deflected with the achromatic metasurface optical components at a shared angle or to or from a focal point at a shared focal length.

Abstract: A static multiview display and method of static multiview display operation provide a static multiview image using diffractive gratings to that encode pixels of the static multiview image. The static multiview display includes a light guide configured to guide plurality of guided light beams and a light source configured to provide the guided light beam plurality having the different radial directions. The static multiview display further includes a plurality of diffraction gratings configured to provide different individual directional light beams from a portion of the radially directed guided light beams. The different individual directional light beams having different intensities and directions corresponding to and representing different view pixels of the static multiview image.

Abstract: A multilayer static multiview display and method of multilayer multiview display operation provide a plurality of multiview images using diffractive scattering of light from guided light beams having different radial directions. The static multiview display includes a first multiview display layer configured to emit directional light beams representing a first multiview image by diffractive scattering light from a radial pattern of guided light beams within the first multiview display layer. The static multiview display further includes a second multiview display layer configured to emit directional light beams representing a second static multiview image by diffractive scattering light from a radial pattern of guided light beams within the second multiview display layer. The provided plurality of multiview images may include a composite color multiview image, a static multiview image, or an animated or quasi-static multiview image.

Abstract: A static multiview display includes a plurality of light emitters offset in a longitudinal direction; a light guide configured to guide light in the longitudinal direction; a collimating light coupler configured to receive light from the light emitters and coupling the light to the light guide; and an array of diffraction gratings to extract light guided by the light guide to provide a multiview image having a direction that is a function of both color and a propagation angle of light guided by the light guide.

Abstract: A grating-coupled light guide concentrates light and diffractively redirects the concentrated light at a non-zero propagation angle as guided light having a predetermined spread angle. The grating-coupled light guide includes a light guide, an optical concentrator, and a grating coupler. The optical concentrator is configured to concentrate light from a light source as concentrated light and the grating coupler is configured to diffractively redirect the concentrated light into the light guide as the guided light. Characteristics of the optical concentrator and grating coupler are configured in combination to determine the non-zero propagation angle and predetermined spread angle. A grating-coupled display system further includes an array of light valves configured to modulate emitted light as a displayed image.

Abstract: An electronic device may include a display that generates light for an optical system that redirects the light towards an eye box. The optical system may include a waveguide, a non-diffractive input coupler, a cross coupler, and an output coupler. The cross coupler may expand the light in a first direction. The cross coupler may perform an even number of diffractions on the light and may couple the light back into the waveguide at an angle suitable for total internal reflection. The output coupler may expand the light in a second direction while coupling the light out of the waveguide. The cross coupler may include surface relief gratings or holographic gratings embedded within the waveguide or formed in a separate substrate. The optical system may direct the light towards the eye box without chromatic dispersion and while supporting an expanded field of view and optical bandwidth.

Abstract: A polarization recycling backlight and a multiview display employ a polarization-selective scattering feature configured to preferentially scatter out a first polarization component of guided light and a polarization conversion structure configured to convert a portion of a second polarization component of the guided light into the first polarization component. The polarization conversion structure includes a subwavelength grating.

Abstract: A unilateral backlight and a unilateral multiview display employ an array of unilateral diffractive elements configured to provide directional light beams having a unilateral direction. A unilateral diffractive element of the unilateral diffractive element array comprises a slanted diffraction grating configured to provide a directional light beam by diffractive scattering of light guided in a light guide. The unilateral multiview display further includes light valves configured to modulate a plurality of directional light beams as multiview image having the unilateral direction.

Abstract: In an example, an apparatus is described that includes a light source, a holographic optical element, a sampling apparatus, and a detector. The light source is configured to emit a beam of excitation light. The holographic optical element is arranged to convert the beam of excitation light into a plurality of beams of excitation light. The sampling apparatus is arranged to project the plurality of beams of excitation light onto a surface outside the apparatus as a two-dimensional pattern of projection points. The sampling apparatus is further arranged to collect scattered radiation emitted by the surface in response to the two-dimensional pattern of projection points. The detector detects a frequency shift in the scattered radiation.

Abstract: Multiview backlighting employs a plasmonic multibeam element having a color-tailored emission pattern to provide directional light beams corresponding to a plurality of different views of a multiview image. A multiview backlight includes a light guide configured to guide light as guided light and a plasmonic multibeam element. The plasmonic multibeam element includes a plasmonic material and is configured to provide emitted light having a color-tailored emission pattern from the guided light. The emitted light includes a plurality of directional light beams having different principal angular directions corresponding to respective different view directions of a multiview display and the color-tailored emission pattern corresponds to an arrangement of color sub-pixels of a view pixel in the multiview display.