Abstract: A system may have a display that includes a plurality of light sources such as light-emitting diodes. The display may be an exterior display that is routinely operated in daytime conditions where ambient light levels are very high. To increase contrast in an exterior display, the display may include a sunlight blocking element. A static sunlight blocking element may include a louver film with asymmetric light blocking portions. The system may include an ambient light sensor that is configured to determine ambient light levels. Based on the detected ambient light level, control circuitry in the system may adjust one or more adjustable components in the display. The display may include an adjustable diffuser that has at least two states with different haze levels. The display may include an adjustable tint layer that has at least two states with different transmission levels.

Abstract: A display may have a display panel with an array of pixels formed from light-emitting diodes. Optical films that help collimate and homogenize light from the light-emitting diode pixels may overlap the light-emitting diodes. A transparent cover may overlap the display. The transparent cover may have an outer surface and an opposing inner surface, which may have areas of compound surface curvature. Louvers that serve to reduce off-axis solar light reflections while allowing light from the display panel to be emitted may be formed from molded polymer supported by a transparent cover layer in the cover. A diffuser may be formed by embedding light-scattering particles in a polymer layer covering the louvers and/or by forming light-scattering surface structures such as ridges and/or other texture on the surface of the polymer layer. Electrically adjustable light modulator layers and electrically adjustable louvers may be used in the display.

Abstract: A system may have an external display that presents content to viewers outside of the system. The external display may have a display panel with an array of pixels formed from light-emitting diodes. Optical films that help collimate and homogenize light from the light-emitting diode pixels may overlap the light-emitting diodes. A transparent cover may overlap the display. The transparent cover may have an outer surface and an opposing inner surface. The outer surface and inner surface may be planar or may have a curved cross-sectional profile. An optical louver layer or other solar rejection layer may be interposed between the inner surface of the transparent cover and the display panel. The louver layer may have a series of elongated parallel louvers formed from an opaque polymer or other material. The louvers may be configured to block sunlight reflections while allowing images on the display panel to be viewed.

Abstract: A system may have a display that includes a plurality of light sources such as light-emitting diodes. The display may be an exterior display that is routinely operated in daytime conditions where ambient light levels are very high. To increase contrast in an exterior display, the display may include a sunlight blocking element. A static sunlight blocking element may include a louver film with asymmetric light blocking portions. The system may include an ambient light sensor that is configured to determine ambient light levels. Based on the detected ambient light level, control circuitry in the system may adjust one or more adjustable components in the display. The display may include an adjustable diffuser that has at least two states with different haze levels. The display may include an adjustable tint layer that has at least two states with different transmission levels.

Abstract: A system may have an exterior display. The exterior display may display symbols that correspond to intended actions for the system or instructions for nearby viewers. The exterior display may include an array of light-emitting diodes, a collimator, a one-way filter to prevent sunlight from washing out the display, and a cover layer. The one-way filter may include a microlens array and a masking layer. The collimator is configured to collimate light from the array of light-emitting diodes and provide the collimated light to the one-way filter. The microlens array receives the collimated light and focuses the collimated light through a plurality of holes in the masking layer. In this way, the majority of display light is passed through the one-way filter towards a viewer. However, the majority of ambient sunlight is blocked by the masking layer, thus preserving a high contrast for the exterior display even in bright sunlight.

Abstract: An electronic device such as a voice-controlled speaker device may have a housing. A speaker and other input-output components and control circuitry may be mounted within the housing. Light-emitting components may emit light that passes through a curved upper top cap portion or other housing structure. The light-emitting components may be interconnected using a flex circuit on a curved substrate or may be mounted on a planar circuit board. A subset of the light-emitting components may be rotated to improve color balance. Optical structures such as light guides, lens, microlenses, and/or a diffuser layer may be disposed over the light-emitting components to promote light mixing, to reduce hotspots, and to improve contrast on the top cap. The diffuser layer may be suspended using a support structure having baffle members to constraint the angular spread of the emitted light. Illuminated or persistently visible glyphs may be displayed in or near the top cap portion.

Abstract: An electronic device such as a voice-controlled speaker device may have a housing. A speaker and other input-output components and control circuitry may be mounted within the housing. Light-emitting components may emit light that passes through a curved upper top cap portion or other housing structure. The light-emitting components may be interconnected using a flex circuit on a curved substrate or may be mounted on a planar circuit board. A subset of the light-emitting components may be rotated to improve color balance. Optical structures such as light guides, lens, microlenses, and/or a diffuser layer may be disposed over the light-emitting components to promote light mixing, to reduce hotspots, and to improve contrast on the top cap. The diffuser layer may be suspended using a support structure having baffle members to constraint the angular spread of the emitted light. Illuminated or persistently visible glyphs may be displayed in or near the top cap portion.

Abstract: An electronic device such as a voice-controlled speaker device may have a housing. A speaker and other input-output components and control circuitry may be mounted within the housing. Light-emitting components may emit light that passes through a curved upper top cap portion or other housing structure. Some of the light-emitting components may be rotated to improve color balance. Optical structures such as a dual-shot injection molded light control plate may be disposed over the light-emitting components to promote light mixing, reduce hotspots, and improve contrast on the top cap. The light control plate may have an upper clear layer with bell-shaped cavity portions configured to help spread light in the lateral direction and may have a reflective lower layer with dish-shaped portions configured to reflect and diffuse light back towards the top cap. The surface of the dish-shaped portions may be provided with microtextured structures to help scatter light.

Abstract: An electronic device includes a housing, a speaker, control circuitry, a plurality of light-emitting components configured to emit light through an upper housing wall or other housing structure. A lens diffuser layer having lenses overlapping respective light-emitting components, a textured diffuser layer formed from textured coatings on a substrate, and a volume diffuser layer having light-scattering structures in a polymer layer might be included to project light from the light-emitting components. A light-guiding portion of the lens diffuser layer may guide light to a circular peripheral edge to form an illuminated ring visible through the upper housing wall.

Abstract: An electronic device may have a display with a backlight. The backlight provides backlight illumination for an array of pixels that is displaying images. The backlight may include an array of cells. Each cell may contain a light source with one or more light-emitting diodes and a cavity reflector that reflects light from the light source outwardly through a diffuser for use in forming the backlight illumination. The light sources may be mounted to a printed circuit. Support posts on the printed circuit may be used to maintain the diffuser at a fixed distance from the printed circuit. Sensors on the printed circuit may be used to measure separation distances between the printed circuit and diffuser. Adjustments to pixel gain profiles can be made based on the measured separation distances.

Abstract: An electronic device such as a voice-controlled speaker device may have a housing. A speaker and other input-output components and control circuitry may be mounted within the housing. Light-emitting components may emit light that passes through a curved upper top cap portion or other housing structure. The light-emitting components may be interconnected using a flex circuit on a curved substrate or may be mounted on a planar circuit board. A subset of the light-emitting components may be rotated to improve color balance. Optical structures such as light guides, lens, microlenses, and/or a diffuser layer may be disposed over the light-emitting components to promote light mixing, to reduce hotspots, and to improve contrast on the top cap. The diffuser layer may be suspended using a support structure having baffle members to constraint the angular spread of the emitted light. Illuminated or persistently visible glyphs may be displayed in or near the top cap portion.

Abstract: A display may have a pixel array such as a liquid crystal pixel array. The pixel array may be illuminated with backlight illumination from a backlight unit. The backlight unit may include an array of light-emitting diodes and a light reflector that helps reflect light from the light-emitting diodes through the pixel array. A color conversion layer may be used to convert light from the light-emitting diodes from blue light to white light. A microlens array layer formed over the color conversion layer may spread the light from the color conversion layer to homogenize the light. To ensure light is emitted from the backlight with a uniform color, the microlens array layer may have different transmittance portions. A central portion of the microlens array layer may transmit more light and reflect less light than an edge portion of the microlens array layer.

Abstract: An array of pixels in a display may be illuminated by a backlight having an array of light-emitting diodes in an array of respective cells. A reflector is used to reflect light from the light-emitting diodes through the array of pixels. Within the cells, the reflector has cross-sectional profiles that help distribute light emitted from the light-emitting diodes toward edges of the cells. A light diffuser layer for the backlight may have a partially reflective layer such as a thin-film interference filter with an angularly dependent transmission. Within each cell, the reflector may have cross-sectional profiles with portions that are parabolic or elliptical.

Abstract: An electronic device may have a display with a backlight. The backlight provides backlight illumination for an array of pixels that is displaying images. The backlight may include an array of cells. Each cell may contain a light source with one or more light-emitting diodes and a cavity reflector that reflects light from the light source outwardly through a diffuser for use in forming the backlight illumination. The light sources may be mounted to a printed circuit. Support posts on the printed circuit may be used to maintain the diffuser at a fixed distance from the printed circuit. The support posts may have opposing first and second ends. The first ends may be attached to the diffuser with fixed connections such as adhesive connections. The second ends may be attached to the printed circuit using floating connections.

Abstract: A display may have a pixel array such as a liquid crystal pixel array. The pixel array may be illuminated with backlight illumination from a backlight unit. The backlight unit may include a printed circuit board, a plurality of light-emitting diodes mounted on the printed circuit board, at least one light spreading layer formed over the printed circuit board that spreads light received from the plurality of light-emitting diodes, a partially reflective layer formed over the at least one light spreading layer, a color conversion layer formed over the partially reflective layer, a collimating layer formed over the color conversion layer, a brightness enhancement film formed over the collimating layer, and a diffuser formed over the brightness enhancement film. The at least one light spreading layer may include two light spreading layers with elongated protrusions that are rotated relative to each other.

Abstract: An electronic device such as a voice-controlled speaker device may have a housing. A speaker and other input-output components and control circuitry may be mounted within the housing. A set of controlled light-emitting components may emit light that passes through an upper housing wall or other housing structure. Light from the light-emitting components may be spread laterally by multiple light diffusing layers such as a lens diffuser layer having lenses overlapping respective light-emitting components, a textured diffuser layer formed from textured coatings on a substrate, and a volume diffuser layer having light-scattering structures in a polymer layer. The lens layer may be formed from a transparent member with integral lenses having curved inner surfaces and opposing curved outer surfaces and central depressions. A light-guiding portion of the transparent member may guide light to a circular peripheral edge to form an illuminated ring visible through the upper housing wall.

Abstract: A display may have a pixel array such as a liquid crystal pixel array. The pixel array may be illuminated with backlight illumination from a backlight unit. The backlight unit may include a printed circuit board, a plurality of light-emitting diodes mounted on the printed circuit board, at least one light spreading layer formed over the printed circuit board that spreads light received from the plurality of light-emitting diodes, a partially reflective layer formed over the at least one light spreading layer, a color conversion layer formed over the partially reflective layer, a collimating layer formed over the color conversion layer, a brightness enhancement film formed over the collimating layer, and a diffuser formed over the brightness enhancement film. The at least one light spreading layer may include two light spreading layers with elongated protrusions that are rotated relative to each other.

Abstract: An electronic device may have a display with a backlight. The backlight provides backlight illumination for an array of pixels that is displaying images. The backlight may include an array of cells. Each cell may contain a light source with one or more light-emitting diodes and a cavity reflector that reflects light from the light source outwardly through a diffuser for use in forming the backlight illumination. The light sources may be mounted to a printed circuit. Support posts on the printed circuit may be used to maintain the diffuser at a fixed distance from the printed circuit. Sensors on the printed circuit may be used to measure separation distances between the printed circuit and diffuser. Adjustments to pixel gain profiles can be made based on the measured separation distances.

Abstract: An electronic device may have a display with a backlight. The backlight provides backlight illumination for an array of pixels that is displaying images. The backlight may include an array of cells. Each cell may contain a light source with one or more light-emitting diodes and a cavity reflector that reflects light from the light source outwardly through a diffuser for use in forming the backlight illumination. The light sources may be mounted to a printed circuit. Support posts on the printed circuit may be used to maintain the diffuser at a fixed distance from the printed circuit. Sensors on the printed circuit may be used to measure separation distances between the printed circuit and diffuser. Adjustments to pixel gain profiles can be made based on the measured separation distances.

Abstract: A display such as a liquid crystal display may have an array of pixels that is illuminated using backlight illumination from a backlight. The backlight may have a light guide layer that distributes light from light-emitting diodes across the display. The light guide layer may have a planar portion that provides backlight illumination to the array of pixels and may have bent edge portions that curve out of the plane of the planar portion. Light scattering structures may be formed in the planar portion to extract backlight illumination from the light guide layer. A light sensor adjacent to the bent portion may monitor leaked light. The light guide layer may have two bent portions on opposing edges of the light guide layer.