Abstract: A touch screen display may have a color filter layer and a thin-film transistor layer. A layer of liquid crystal material may be located between the color filter layer and the thin-film transistor (TFT) layer. The TFT layer may include thin-film transistors formed on top of a glass substrate. Each display pixel in the TFT layer may include first and second TFTs coupled in series between a data line and a storage capacitor. The first TFT may have a gate that is coupled to a gate line. The second TFT may have a gate that is coupled to a control line that is different than the gate line. A global enable signal may be provided on the control line, where the enable signal is asserted during display intervals and is deasserted during touch intervals. The second TFT may be formed using a top-gate TFT or a bottom-gate TFT arrangement.

Abstract: A display may be provided with an active central region and a peripheral inactive region. The display may have one or more flexible edges in the peripheral inactive region. Conductive lines may pass between components in the active central region such as display pixels and touch sensor electrodes and components in the inactive peripheral region such as gate driver circuitry and patterned interconnect lines. Each conductive line may have an unbent segment on a portion of a display layer in the active central region and may have a segment on the bent edge of the display layer. The display layer may be formed from a polymer or other flexible material. The bent segments may be configured to be less susceptible to increases in resistance from bending than the unbent segments.

Abstract: Displays such as organic light-emitting diode displays may be provided with touch sensing capabilities. A touch sensor may be formed from electrodes located on a thin-film encapsulation layer or one or more sides of a polarizer. A single-sided or double-sided touch sensor panel may be attached to the upper or lower surface of a polarizer. Control circuitry may be used to provide control signals to light-emitting diodes in the display using a grid of control lines. The control lines and transparent electrode structures such as indium tin oxide structures formed on a thin-film encapsulation layer or polarizer may be used as electrodes for a touch sensor. Displays may have active regions and inactive peripheral portions. The displays may have edge portions that are bent along a bend axis that is within the active region to form a borderless display. Virtual buttons may be formed on the bent edge portions.

Abstract: An organic light-emitting diode display may have an array of pixel circuits. Each pixel circuit may contain an organic light-emitting diode that emits light, a drive transistor that controls current flow through the diode, and additional transistors such as switching transistors for loading data into the pixel circuit and emission transistors for enabling and disabling current flow through the drive transistor and diode. Gate driver circuitry may produce emission control signals that control the emission transistors. Display driver circuitry may generate a start signal with a digitally controlled pulse width. The start signal may be applied to shift register circuitry in the gate driver circuitry. The pulse width of the start signal may be adjusted to adjust the luminance of the display.

Abstract: A display may have an array of pixels. The array of pixels may have a shape such as a circular shape or other shape with a curved edge. Display driver circuitry may supply data signals to the pixels using folded vertical data lines and bisected horizontal gate lines. Each folded vertical lines may have a first segment in a left half of the array and a second segment in a right half of the display. Curved coupling segments in an inactive area of the display may be used in joining the first and second segments. Display driver circuits may be provided in top and bottom portions of the inactive area to supply data to respective top and bottom portions of the array. Gate driver output buffers may have different strengths in different rows of the array.

Abstract: An electronic device may include a display such as a light-emitting diode display. The electronic device may be a head-mounted device that provides a virtual reality or augmented reality environment to a user. To reduce artifacts in the display, a display may be operable in both a normal scanning mode and a partial scanning mode. In the normal scanning mode, every row of the display may be enabled to emit light in each frame. In the partial scanning mode, only a subset of the rows of the display may be enabled to emit light in each frame. The display may have a higher refresh rate in the partial scanning mode than in the normal scanning mode. To ensure uniform transistor stress across the display, the scanning driver for the display may scan the disabled rows in the partial scanning mode even though the rows will not be used to emit light.

Abstract: An electronic device may include a display such as a light-emitting diode display. The electronic device may be a head-mounted device that provides a virtual reality or augmented reality environment to a user. To reduce artifacts in the display, a display may be operable in both a normal scanning mode and a partial scanning mode. In the normal scanning mode, every row of the display may be scanned in each frame. In the partial scanning mode, only a subset of the rows of the display may be scanned in each frame. The display may have a higher refresh rate in the partial scanning mode than in the normal scanning mode. The gate driver circuitry may include a shift register that includes a plurality of register circuits. At least one register circuit may have a first input and a second input that is different than the first input.

Abstract: A display may have an array of pixels each of which has a light-emitting diode such as an organic light-emitting diode. A drive transistor and an emission transistor may be coupled in series with the light-emitting diode of each pixel between a positive power supply and a ground power supply. The pixels may include first and second switching transistors. A data storage capacitor may be coupled between a gate and source of the drive transistor in each pixel. Signal lines may be provided in columns of pixels to route signals such as data signals, sensed drive currents from the drive transistors, and predetermined voltages between display driver circuitry and the pixels. The switching transistors, emission transistors, and drive transistors may include semiconducting-oxide transistors and silicon transistors and may be n-channel transistors or p-channel transistors.

Abstract: Display backplanes and pixel element structures are described. In an embodiment, a pixel electrode is located between two stacked data lines, with a left edge of the pixel electrode being separated from a first lower data line by approximately a same distance as a right edge of the pixel electrode is separated from a second lower data line.

Abstract: This application relates to methods and apparatus for refreshing a display device at various frequencies. Specifically, multiple areas of the display device can be refreshed concurrently at different frequencies. In this way, when static content is being displayed in certain areas of the display device, those certain areas can be refreshed at a lower rate than areas displaying dynamic content such as video or animation. By refreshing at lower rates, the energy consumed by the display device and subsystems associated with the display device can be reduced. Additionally, processes for reducing flicker when refreshing the display device at different refresh rates are disclosed herein.

Abstract: An electronic device may include a display having an array of display pixels on a substrate. The display pixels may be organic light-emitting diode display pixels or display pixels in a liquid crystal display. In an organic light-emitting diode display, hybrid thin-film transistor structures may be formed that include semiconducting oxide thin-film transistors, silicon thin-film transistors, and capacitor structures. The capacitor structures may overlap the semiconducting oxide thin-film transistors. Organic light-emitting diode display pixels may have combinations of oxide and silicon transistors. In a liquid crystal display, display driver circuitry may include silicon thin-film transistor circuitry and display pixels may be based on oxide thin-film transistors. A single layer or two different layers of gate metal may be used in forming silicon transistor gates and oxide transistor gates. A silicon transistor may have a gate that overlaps a floating gate structure.

Abstract: A touch sensor panel comprising a first touch node electrode of a plurality of touch node electrodes, the first touch node electrode coupled to a first sense connection comprising a first set of traces, the first sense connection configured to have a first resistance per unit length that varies along a length of the first sense connection, and a second touch node electrode of the plurality of touch node electrodes, the second touch node electrode coupled to a second sense connection comprising a second set of traces, the second sense connection configured to have a second resistance per unit length that varies along a length of the second sense connection differently than the first resistance per unit length varies along the length of the first sense connection. An effective resistance of the first sense connection and the second sense connection are equal.

Abstract: A system and device for driving high resolution monitors while reducing artifacts thereon. Utilization of Z-inversion polarity driving techniques to drive pixels in a display reduces power consumption of the display but tends to generate visible horizontal line artifacts caused by capacitances present between the pixels and data lines of the display. By introducing a physical shield between the pixel and data line elements, capacitance therebetween can be reduced, thus eliminating the cause of the horizontal line artifacts. The shield may be a common voltage line (Vcom) of the display.

Abstract: Touch screens with more compact border regions can include an active area that includes touch sensing circuitry including drive lines, and a border region around the active area. The border region can include an area of sealant deposited on conductive lines, and transistor circuitry, such as gate drivers, between the active area and the sealant. The conductive lines can extend from the sealant to the active area without electrically connecting to the transistor circuitry. The conductive lines can have equal impedances and can connect the drive lines to a touch controller off of the touch screen. A set of drive signal characteristics for the drive lines can be obtained by determining a transfer function associated with each drive line, obtaining an inverse of each transfer function, and applying a set of individual sense signal characteristics to the inverse transfer functions to obtain the corresponding set of drive signal characteristics.

Abstract: A display may have an active area with an array of pixels to display images. An inactive area in the display may be formed from an opening in the active area. The inactive area may be enclosed by the pixels in the active area. An inactive border may run along an edge of the inactive area. A grid of positive power supply lines may be used to supply power to the pixels. Initialization voltage lines may be used to distribute initialization voltages to the pixels for use during transistor threshold voltage compensation operations. The inactive border may be free of positive power supply lines and initialization voltages lines. Control signal lines and data lines may pass through the inactive border to supply control signals and data signals respectively to the pixels. The display may have thin-film transistor circuitry with multiple layers of data lines.

Abstract: A display may have an array of pixels to display images. Gate line driver circuitry may have stages that supply gate line signals. A gate line may be located in each row of the pixels. Each stage may have an output block that produces a respective one of the gate line signals and may have a carry block that separately produces a carry signal that is provided to a later stage in the gate line driver circuitry. A memory may be provided in at least some of the stages to store signals produced by the output blocks during intraframe pausing operations. At the end of an intraframe pause, the stored signals may be used in restarting production of the gate line signals by output blocks in the gate line driver stages. Circuitry may be used to separately reset the output block and suppress carry signal production by the carry block.

Abstract: An organic light-emitting diode display may have an array of pixels. Each pixel may have multiple subpixels of different colors. To avoid undesired color shifts when operating the display, the display may be configured so that subpixels of different colors are not coupled to each other through parasitic capacitances. The subpixels may include red, green, and blue subpixels or subpixels of other colors. Each subpixel may include an organic light-emitting diode having an anode and a cathode. The anode of each organic light-emitting diode may be coupled to a respective storage capacitor. Capacitive coupling between subpixels can be minimized by configuring the subpixel structures of each pixel so that the storage capacitors of the subpixels do not overlap the anodes of other subpixels in the pixel. Anode and capacitor overlap with subpixel data lines may also be reduced or eliminated.

Abstract: A liquid crystal display having an outer layer such as a thin-film transistor layer and an inner layer such as a color filter layer may be mounted in a metal device housing. Transparent conductive coating material may be formed on display layers. The transparent conductive coating material may include a layer on the upper surface of the thin-film transistor layer, a layer on the lower surface of the color filter layer, and an edge coating that extends between the upper surface layer and lower surface layer. Electrostatic discharge protection structures for the display may include a conductive elastomeric gasket that couples the upper surface layer to an inner surface of the housing, a conductive tape that couples the lower surface layer to the inner surface, and a conductive material on the inner surface that contacts the edge coating.

Abstract: A display may have an array of pixels each of which has a light-emitting diode such as an organic light-emitting diode. A drive transistor and an emission transistor may be coupled in series with the light-emitting diode of each pixel between a positive power supply and a ground power supply. The pixels may include first and second switching transistors. A data storage capacitor may be coupled between a gate and source of the drive transistor in each pixel. Signal lines may be provided in columns of pixels to route signals such as data signals, sensed drive currents from the drive transistors, and predetermined voltages between display driver circuitry and the pixels. The switching transistors, emission transistors, and drive transistors may include semiconducting-oxide transistors and silicon transistors and may be n-channel transistors or p-channel transistors.

Abstract: An electronic device may include a display having an array of display pixels on a substrate. The display pixels may be organic light-emitting diode display pixels or display pixels in a liquid crystal display. In an organic light-emitting diode display, hybrid thin-film transistor structures may be formed that include semiconducting oxide thin-film transistors, silicon thin-film transistors, and capacitor structures. The capacitor structures may overlap the semiconducting oxide thin-film transistors. Organic light-emitting diode display pixels may have combinations of oxide and silicon transistors. In a liquid crystal display, display driver circuitry may include silicon thin-film transistor circuitry and display pixels may be based on oxide thin-film transistors. A single layer or two different layers of gate metal may be used in forming silicon transistor gates and oxide transistor gates. A silicon transistor may have a gate that overlaps a floating gate structure.