Abstract: An electronic device may provide visual content at a virtual image distance that is farther from a user than the physical distance of the device from the user. A display in the device may have a transmissive spatial light modulator and beam steering device that are illuminated by a plane wave illumination system to provide computer-generated hologram images, may have a waveguide-based system that ensures that image content is presented at a desired virtual image distance, or may be a light-field display. The display may be used to display a left image in a left eye box and a right image in a right eye box. When viewed from the eye boxes, the left and right images fuse and are visible at a virtual image distance that is farther from the user than the distance physically separating the eye boxes from the display.

Abstract: An electronic device such as a head-mounted display may have a display system that produces images. The display system may have one or more pixel arrays (26-1, 26-2) such as liquid-crystal-on-silicon pixel arrays. Images from the display system may be coupled into a waveguide (116) by an input coupler system (114X, 114Y) and may be coupled out of the waveguide in multiple image planes using an output coupler system (120X, 120Y). The input and output coupler systems may include single couplers, stacks of couplers, and tiled arrays of couplers. Multiplexing techniques such as wavelength multiplexing, polarization multiplexing, time-division multiplexing, multiplexing with image light having different ranges of angular orientations, and/or tunable lens techniques may be used to present images to a user in multiple image planes.

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: An optical component includes a block of a transparent material, having a trapezoidal cross-section defined by first and second parallel, rectangular faces on mutually-opposing sides of the block and third and fourth faces oriented diagonally at opposing ends of the first and second faces. One or more planar, partially-reflecting layers extend within the block between the third and fourth faces in an orientation parallel to the first and second faces.

Abstract: An electronic device may have a reflective display with a pixel array that generates images. The reflective display may be illuminated by an illumination system. Light from the illumination system may be reflected by the pixel array as image light. The image light may be provided to a viewer using a waveguide with diffractive input and output couplers. The illumination system may have a waveguide. The illumination system may also have a light source such as one or more light-emitting diodes. Light from the light source may be coupled into the waveguide of the illumination system by a diffractive coupler such as volume hologram that serves as an input coupler. Light from the light source may be routed to the display to illuminate the display using the waveguide in the illumination system and a diffractive coupler such as a volume hologram that serves as an output coupler.

Abstract: An electronic device may include an optical combiner with a waveguide. The waveguide may have an output coupler that directs high resolution light towards an eye box within a field of view. Peripheral light sources may provide low resolution peripheral light to the eye box about a periphery of the field of view. The peripheral light sources may be mounted to a frame for the waveguide, to an additional substrate mounted to the frame and overlapping the waveguide, in a low resolution projector that projects the peripheral light towards reflective structures in the additional substrate, or in a display module that produces the high resolution light. The optical combiner may overlay real world light with the high resolution light and the low resolution peripheral light.

Abstract: An electronic device may have a light source such as a laser light source. The light source may emit light into a waveguide. A phase grating may diffract the light that is emitted into the waveguide to produce diffracted light. The diffracted light may be oriented parallel to a surface normal of an angled edge of the waveguide and parallel to a surface normal of a microelectromechanical systems mirror element in a two-dimensional scanning microelectromechanical systems mirror that is coupled to the edge of the waveguide. A wave plate may be interposed between the mirror and the edge of the waveguide to change the polarization state of light reflected from the mirror element relative to incoming diffracted light from the phase grating. The phase grating may be configured so that the reflected light is not diffracted by the phase grating.

Abstract: An electronic device such as a head-mounted display may have a display system that produces images. The display system may have one or more pixel arrays (26-1, 26-2) such as liquid-crystal-on-silicon pixel arrays. Images from the display system may be coupled into a waveguide (116) by an input coupler system (114X, 114Y) and may be coupled out of the waveguide in multiple image planes using an output coupler system (120X, 120Y). The input and output coupler systems may include single couplers, stacks of couplers, and tiled arrays of couplers. Multiplexing techniques such as wavelength multiplexing, polarization multiplexing, time-division multiplexing, multiplexing with image light having different ranges of angular orientations, and/or tunable lens techniques may be used to present images to a user in multiple image planes.

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: An electronic device may have a reflective display with a pixel array that generates images. The reflective display may be illuminated by an illumination system. Light from the illumination system may be reflected by the pixel array as image light. The image light may be provided to a viewer using a waveguide with diffractive input and output couplers. The illumination system may have a waveguide. The illumination system may also have a light source such as one or more light-emitting diodes. Light from the light source may be coupled into the waveguide of the illumination system by a diffractive coupler such as volume hologram that serves as an input coupler. Light from the light source may be routed to the display to illuminate the display using the waveguide in the illumination system and a diffractive coupler such as a volume hologram that serves as an output coupler.

Abstract: An electronic device may include a display system for presenting images close to a user's eyes. The display system may include a display unit that directs light and an optical system that redirects the light from the display unit towards a user's eyes. The optical system may include an input coupler and an output coupler formed on a waveguide. The input coupler may redirect light from the display unit so that it propagates in the waveguide towards the output coupler. The output coupler may redirect the light from the input coupler so that it exits the waveguide towards the user's eyes. A light-redirecting element may be used to redirect edge light that would otherwise be outside of the user's field of view towards the user's eyes.

Abstract: An electronic device may have a light source such as a laser light source. The light source may emit light into a waveguide. A phase grating may diffract the light that is emitted into the waveguide to produce diffracted light. The diffracted light may be oriented parallel to a surface normal of an angled edge of the waveguide and parallel to a surface normal of a microelectromechanical systems mirror element in a two-dimensional scanning microelectromechanical systems mirror that is coupled to the edge of the waveguide. A wave plate may be interposed between the mirror and the edge of the waveguide to change the polarization state of light reflected from the mirror element relative to incoming diffracted light from the phase grating. The phase grating may be configured so that the reflected light is not diffracted by the phase grating.