Abstract: A display may include one or more display pixels in an array of pixels. A display pixel may include a storage capacitor chat stores a pixel data signal. The storage capacitor may be formed from a pixel electrode structure, a capacitor electrode structure, and a common electrode structure that is interposed between the pixel electrode structure and capacitor electrode structures. Each electrode structure may be formed from transparent conductive materials deposited on respective display layers. The pixel electrode structure and capacitor electrode structure may be electrically coupled by a conductive via structure that extends through the display layers without contacting the common electrode structure. The conductive via structure may contact underlying transistor structures such as a source-drain structure.

Abstract: An electronic device may include display layers such as liquid crystal display layers and a backlight unit that provides illumination for the display layers. The backlight unit may include light-emitting diodes that emit light into the edge of a light guide film. To minimize the inactive area of the display, the light-emitting diodes may be tightly spaced to approximate a line light source instead of point light sources. Color and/or luminance compensation layers may be incorporated at various locations within the backlight structures to ensure that the backlight provided to the display layers is homogenous. A thin-film transistor layer of the display may be coupled to a printed circuit board by a flexible printed circuit. The flexible printed circuit may have additional solder mask layers to improve robustness, may include encapsulation, and may have traces with a varying pitch.

Abstract: A display may have display layers that form an array of pixels. The display layers may include a first layer that includes a light-blocking matrix and a second layer that overlaps the first layer. The first layer may include quantum dot elements formed in openings in the light-blocking matrix. The light-blocking matrix may be formed from a reflective material such as metal. The second layer may include color filter elements that overlap corresponding quantum dot elements in the first layer. Substrate layers may be used to support the first and second layers and to support thin-film transistor circuitry that is used in controlling light transmission through the array of pixels. The display layers may include a liquid crystal layer, polarizer layers, filter layers for reflecting red and green light and/or other light to enhance light recycling, and layers with angularly dependent transmission characteristics.

Abstract: Aspects of the subject technology relate to gaze-dependent visual encryption of electronic device displays. Each display frame that is displayed on the electronic device display may include a clear-display region around the user's gaze location and an obscured region outside the clear-display region. In this way, only the display content that the user is actively viewing is recognizable and understandable and an onlooker such as an unwanted observer looking over the user's shoulder is unable to understand what is displayed. The obscured region of each display frame may be generated such that the overall look and structure of that region is unchanged, but the content is unintelligible. In this way, the visual experience of the user is not disrupted or distracted by the visual encryption and the eye of the onlooker is not guided to the clear-display region by the visual encryption.

Abstract: Systems and methods are provided for improving displayed image quality of an electronic display that includes a display pixel. The electronic display displays a first image frame directly after a second image frame by applying an analog electrical signal to the display pixel. To facilitate display of the first image frame, circuitry receives image data corresponding to the image frame, in which the image data includes a grayscale value that indicates target luminance of the display pixel; determines expected refresh rate of the first image frame based at least in part on actual refresh rate of the second image frame; determines a pixel response correction offset based at least in part on the expected refresh rate of the first image frame; and determines processed image data by applying the pixel response correction offset to the grayscale value, in which the processed image data indicates magnitude of the analog electrical signal.

Abstract: Liquid crystal display systems and methods of operation are described. In an embodiment, a liquid crystal display pixel cell includes an insulation layer spanning over a passivation layer and the plurality of signal electrodes such that it separates the signal electrodes from polymer alignment layer for the liquid crystal. In an embodiment, a method of operating a liquid crystal display panel includes temporal compensation of the Vcom value as a function of time and one or more operating parameters.

Abstract: Light emitting structures are described in which vertical inorganic semiconductor-based light emitting diodes (LEDs) with hexagon shaped sidewalls are mounted within corresponding circular reflective well structures. Diffuser layers may additionally laterally surround the hexagon shaped sidewalls within the circular reflective well structures.

Abstract: An electronic device may have a display. Input-output circuitry in the electronic device may be used to gather input from a viewer of the display. The input-output circuitry may include a gaze tracking system that gathers point-of-gaze information, vergence information, and head position information, may be a biometric sensor, may be an input device such as a button or touch sensor, may capture hand gestures, and/or may gather other information. The display may include a pixel array for producing images. An adjustable reflectance and transmittance layer may overlap the pixel array. Control circuitry in the electronic device may individually adjust different areas of the adjustable reflectance and transmittance layer. The control circuitry may place each area in a reflective mirror more or in a content-displaying mode and may move the areas in response to the information.

Abstract: An electronic device may generate content that is to be displayed on a display. The display may have an array of liquid crystal display pixels for displaying image frames of the content. The display may be operated in at least a normal viewing mode, a privacy mode, an outdoor viewing mode, and a power saving mode. The different view modes may exhibit different viewing angles. In one configuration, the display may include a backlight unit that generates a collimated light source and that includes a switchable diffuser film for selectively scattering the collimated light source depending on the current viewing mode of the display. In another configuration, the display may include a backlight unit that generates a scattered light source that includes a switchable microarray structure such as a switchable mirror structure or a tunable microlens array for selectively collimating the scattered light source depending on the current viewing mode.

Abstract: An electronic device may be provided with a display. An optical component window may be formed in the inactive area of the display. The optical component window may transmit infrared light from an infrared light source. The infrared light source may include a diffuser to allow the light source to operate in a flood illumination mode and a structured light mode. The diffuser may include liquid crystal material between first and second substrates. A sealant may surround the liquid crystal layer, and one or more spacer walls may be located between the sealant and the liquid crystal layer. An additional spacer wall may be used outside of the sealant to prevent metal from creating an electrical short between electrodes in the diffuser. Conductive material in the sealant may be used to couple a top electrode to a metal pad on a bottom substrate.

Abstract: A display may include an optical film to promote sunglass-friendly viewing of the display. Displays may include linear polarizers. For example, a liquid crystal display may have a linear polarizer above a liquid crystal layer, whereas an organic light-emitting diode display may have a linear polarizer that forms a portion of a circular polarizer to reduce reflections in the display. Displays that emit linearly polarized light may not be compatible with polarized sunglasses. To ensure an optimal user experience for users wearing sunglasses, displays may include sunglass-friendly optical films. A sunglass-friendly optical film may be a film formed from a birefringent material such as a polymer or liquid crystal. The sunglass-friendly optical film may have an optical axis that is at a 45° angle relative to the optical axis of the underlying linear polarizer. The sunglass-friendly optical film may be patterned to have reduced thickness regions.

Abstract: This application relates to systems, methods, and apparatus for compensating voltage for pixels of a display panel based on the location of the pixels within the display panel. An amount of voltage compensation is assigned to each pixel or a group of pixels within the display panel in accordance with a calibration of the display panel. During operation of the display panel, pixel data is generated for a location of the display panel, and the pixel data is modified according to the amount of voltage compensation corresponding to the location. By modifying the pixel data in this way, spatial variations in voltage across the display panel can be mitigated in order to reduce the occurrence of certain display artifacts at the display panel.

Abstract: An electronic device may generate content that is to be displayed on a display. The display may have an array of liquid crystal display pixels for displaying image frames of the content. The display may be operated in at least a normal viewing mode, a privacy mode, an outdoor viewing mode, and a power saving mode. The different view modes may exhibit different viewing angles. In one configuration, the display may include a backlight unit that generates a collimated light source and that includes a switchable diffuser film for selectively scattering the collimated light source depending on the current viewing mode of the display. In another configuration, the display may include a backlight unit that generates a scattered light source that includes a switchable microarray structure such as a switchable mirror structure or a tunable microlens array for selectively collimating the scattered light source depending on the current viewing mode.

Abstract: Liquid crystal display systems and methods of operation are described. In an embodiment, a liquid crystal display pixel cell includes an insulation layer spanning over a passivation layer and the plurality of signal electrodes such that it separates the signal electrodes from polymer alignment layer for the liquid crystal. In an embodiment, a method of operating a liquid crystal display panel includes temporal compensation of the Vcom value as a function of time and one or more operating parameters.

Abstract: Devices and methods related to high-contrast liquid crystal displays (LCDs) are provided. For example, such an electronic device may include an LCD with two liquid crystal alignment layers not symmetric to one another and upper and lower polarizing layers respectively above and below the alignment layers. Light transmittance through the plurality of pixels may increase monotonically with gray scale voltage. The display may operate using a gray scale level 0 voltage higher than a minimum gray scale level 0 voltage capability of the display. Additionally or alternatively, liquid crystal molecular alignment axes of the two alignment layers may be offset from one another by an angle other than a multiple of 180 degrees. Additionally or alternatively, a first polarizing axis of the upper polarizing layer or a second polarizing axis of the lower polarizing layer, or both, may be neither parallel nor perpendicular to one of the liquid crystal molecular alignment axes.

Abstract: A display may have display layers that form an array of pixels. The display layers may include a first layer that includes a light-blocking matrix and a second layer that overlaps the first layer. The first layer may include quantum dot elements formed in openings in the light-blocking matrix. The light-blocking matrix may be formed from a reflective material such as metal. The second layer may include color filter elements that overlap corresponding quantum dot elements in the first layer. Substrate layers may be used to support the first and second layers and to support thin-film transistor circuitry that is used in controlling light transmission through the array of pixels. The display layers may include a liquid crystal layer, polarizer layers, filter layers for reflecting red and green light and/or other light to enhance light recycling, and layers with angularly dependent transmission characteristics.

Abstract: An electronic device may have a display. Input-output circuitry in the electronic device may be used to gather input from a viewer of the display. The input-output circuitry may include a gaze tracking system that gathers point-of-gaze information, vergence information, and head position information, may be a biometric sensor, may be an input device such as a button or touch sensor, may capture hand gestures, and/or may gather other information. The display may include a pixel array for producing images. An adjustable reflectance and transmittance layer may overlap the pixel array. Control circuitry in the electronic device may individually adjust different areas of the adjustable reflectance and transmittance layer. The control circuitry may place each area in a reflective mirror more or in a content-displaying mode and may move the areas in response to the information.

Abstract: An electronic device may generate content that is to be displayed on a display. The display may have an array of liquid crystal display pixels for displaying image frames of the content. A charge accumulation tracker may analyze the image frames to determine when there is a risk of excess charge accumulation. The charge accumulation tracker may implement a physically derived circuit model of the pixels. A charge accumulation input response matrix and a charge accumulation state response matrix for the model may be stored in look-up table circuitry and used in computing a current charge accumulation state based on current pixel voltage information and previous state information. The impact of temperature, backlight illumination level, frame duration, and other factors may be taken into account in evaluating the current charge accumulation state.

Abstract: System and method for improving displayed image quality of an electronic display that displays a first image frame by applying a first voltage to a display pixel and a second image frame directly before the first image frame by applying a second voltage to the display pixel. A display pipeline is communicatively coupled to the electronic display and receives first image data corresponding with the first image frame, where the image data includes a first grayscale value corresponding with the display pixel. Additionally the display pipeline determines an inversion balancing grayscale offset based at least in part on the first grayscale value when polarity of the first voltage and polarity of the second voltage are the same and determines magnitude of the first voltage by applying the inversion balancing grayscale offset to the first grayscale value to reduce likelihood of a perceivable luminance spike when displaying the first image frame.

Abstract: Devices and methods for useful in providing localized synchronized and/or dynamic in-band internal gamma code adjustment per frame period are provided. By way of example, a display panel includes a data driver, which includes a first DAC configured to provide an internal gamma voltage signal to cause a first adjustment to an image data signal. The first adjustment is configured to selectively adjust the image data signal based at least in part on a refresh rate or a frame rate of the display panel. The data driver includes a second DAC coupled to the first DAC and configured to provide an external gamma voltage signal configured to provide a second adjustment to the image data signal, and an output buffer configured to supply the image data signal to pixels of the display panel, wherein the image data signal comprises the first adjustment and the second adjustment.