Abstract: A display may have a thin-film-transistor layer with a substrate layer. A layer of dielectric may be formed on the substrate layer and may have an upper surface and a lower surface. The thin-film-transistor layer may include an array of display pixels. Data lines and gate lines may provide signals to the display pixels. Gate driver circuitry in an inactive peripheral portion of the display may include a gate driver circuit for each gate line. The gate driver circuits may include thin-film transistors that are formed on the upper surface of the layer of dielectric. Signal lines such as a gate low line, a gate routing line coupled between the gate driver circuits, and a common electrode line may be formed from two or more layers of metal to reduce their widths or may be embedded within the dielectric layer between the upper and lower surfaces under the thin-film transistors.

Abstract: Devices and methods for reducing or eliminating image artifacts are provided. By way of example, a display panel includes row common voltage (VCOM) electrodes each having a first width. The row VCOM electrodes extend along a first direction of the display panel. The display panel also includes column VCOM electrodes each having a second width. The column VCOM electrodes extend along a second direction of the display panel perpendicular to the first direction. The second width of the column VCOM electrodes may be substantially less than the first width of the row VCOM electrodes to increase a resistance of the column VCOM electrodes. By increasing the resistance of the column VCOM electrodes, image artifacts on the display panel may be prevented or eliminated.

Abstract: Methods and devices for shielding displays from electrostatic discharge (ESD) are provided. In one example, a display of an electronic device may include a high resistivity shielding layer configured to protect electrical components from static charges. The display may also include a conductive layer electrically coupled to the high resistivity shielding layer and configured to decrease a discharge time of static charges from the high resistivity shielding layer. The display may include a grounding layer and a conductor electrically coupled between the conductive layer and the grounding layer to direct static charges from the conductive layer to the grounding layer.

Abstract: A display may have a thin-film-transistor layer with a substrate layer. A layer of dielectric may be formed on the substrate layer and may have an upper surface and a lower surface. The thin-film-transistor layer may include an array of display pixels. Data lines and gate lines may provide signals to the display pixels. Gate driver circuitry in an inactive peripheral portion of the display may include a gate driver circuit for each gate line. The gate driver circuits may include thin-film transistors that are formed on the upper surface of the layer of dielectric. Signal lines such as a gate low line, a gate routing line coupled between the gate driver circuits, and a common electrode line may be formed from two or more layers of metal to reduce their widths or may be embedded within the dielectric layer between the upper and lower surfaces under the thin-film transistors.

Abstract: An electronic device may have a display such as a liquid crystal display. The display may include a layer of liquid crystal material interposed between a color filter layer and a thin-film transistor layer. The thin-film transistor layer may be provided with capacitive touch sensor electrodes. Wide metal lines on the thin-film transistor layer may be used to inhibit parasitic capacitances during touch sensor mode. The color filter layer may include a layer of black masking material that surrounds the active display area. A light-curable adhesive may used to attach the color filter layer to the thin-film transistor layer. Openings may be formed in the black masking material and in the metal lines on the thin-film transistor layer. The adhesive may be cured by applying ultraviolet light to the adhesive through the openings in the black masking material and through the openings in the metal lines.

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: Methods and devices employing charge removal circuitry are provided to reduce or eliminate artifacts due to a bias voltage remaining on an electronic display after the display is turned off. In one example, a method may include connecting a pixel electrode of a display to ground through charge removal circuitry while the display is off (e.g., using depletion-mode transistors that are active when gates of the depletion-mode transistors are provided a ground voltage). When a corresponding common electrode is also connected to ground, a voltage difference between the pixel electrode and common electrode may be reduced or eliminated, preventing a bias voltage from causing display artifacts in the pixel.

Abstract: A touch screen to reduce touch pixel coupling. In some examples, the touch screen can include a first display pixel and a second display pixel in a row of display pixels, where the first display pixel can be configurable to be decoupled from the second display pixel during at least a touch sensing phase of the touch screen. In some examples, the touch screen can include a display pixel having a first and a second transistor, where the second transistor can be electrically connected to a gate terminal of the first transistor, and can be diode-connected. In some examples, the touch screen can include two display pixels, each display pixel having two transistors, where two of the transistors can be electrically connected to a first gate line, and the remaining two transistors can be individually electrically connected to a second and third gate line, respectively.

Abstract: A display may be provided with integral touch functionality. The display may include a common electrode layer having row electrodes arranged in rows and column electrodes interposed between the row electrodes of each row. The row electrodes may be electrically coupled by conductive paths. The row and column electrodes may be coupled to touch sensor circuitry that uses the row and column electrodes to detect touch events. Each electrode of the common electrode layer may cover a respective portion of an array of pixels. Each pixel of the display may have a respective aperture. The conductive paths that electrically couple row electrodes of the common electrode layer may cover or otherwise block some light from passing through pixels, resulting in reduced apertures. Dummy structures may be provided for other pixels that modify the apertures of the other pixels to match the reduced apertures associated with the conductive paths.

Abstract: A touch sensitive device that can detect the amount of pressure being applied to a touch screen from a user or other external object is provided. A spacer of the touch screen can be coated with a layer of conductive material and the change in capacitance between the spacer and various circuit elements of the touch screen can be measured. The change in capacitance can be correlated to the amount of pressure being applied to the touch screen, thus providing a method to determine the pressure being applied. During operation of the device, the system can time multiplex touch, display and pressure sensing operations so as to take advantage of an integrated touch and display architecture.

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: An electronic display system has a light transmissive panel, a region of display elements on the panel, and source lines coupled to the display elements. A demultiplexor circuit has multiple groups of pass gates. Each pass gate has a pair of complimentary on-panel transistors, and the signal outputs of each group are connected to a respective group of the source lines. A display driver integrated circuit (IC) receives video data and timing control signals. A signal input of each group of pass gates is connected to a respective output pin of the driver IC. The display driver IC provides digital timing control signals to control the pass gates of the demultiplexor circuit. Other embodiments are also described.

Abstract: A transistor that may be used in electronic displays to selectively activate one or more pixels. The transistor includes a metal layer, a silicon layer deposited on at least a portion of the metal layer, the silicon layer includes an extension portion that extends a distance past the metal layer, and at least three lightly doped regions positioned in the silicon layer. The at least three lightly doped regions have a lower concentration of doping atoms than other portions of the silicon layer forming the transistor.

Abstract: A touchscreen system has a light transparent panel, a region of display elements below the panel, and a transparent conductor plate that overlays the region of display elements. The transparent conductor plate is made of a number of electrode segments. Touch driver circuits are positioned on the panel and in a border region thereof. Each touch driver circuit has a respective latch and a respective output stage. The output stage is coupled to a respective one of the electrode segments and has a signal input to receive a touch stimulus signal. The touch driver circuits may be operated in shift register fashion so that the touch stimulus signal is pulsed sequentially to the electrode segments. Other embodiments are also described and claimed.

Abstract: Disclosed embodiments relate to signal routings for use in a display device. The display device may include a liquid crystal display (LCD) panel having multiple pixels arranged in rows and columns. Each of the pixels includes a pixel electrode and a thin-film transistor (TFT). The LCD may include a conductive signal routing portion having a first metallic layer, a second metallic layer formed directly on the first metallic layer, and a third metallic layer formed directly on the second metallic layer. The first metallic layer may include a contact terminal. The second metallic layer when combined with the third metallic layers may decrease the resistance of the third metallic layer.

Abstract: An electronic device display may have an array of display pixels that are controlled using a grid of data lines and gate lines. The display may include compact gate driver circuits that perform gate driver operations to drive corresponding gate lines. Each compact gate driver circuit may include a first driver stage and a second driver stage. The first driver stage may receive a start pulse signal and produce a control signal. The control signal may be stored by a capacitor to identify a control state of the gate driver circuit. The second driver stage may receive the control signal, a clock signal, and a corresponding inverted clock signal and drive the corresponding gate line based on the received signals. The second driver stage may include pass transistor circuitry that passes the clock signal to the corresponding gate line and may include short circuit protection circuitry.

Abstract: The antenna on hand held devices, such as the iPhone or iPad, can be subject to interference from other circuitry on the device. Such interference may come from high frequency switching of nearby display circuitry, such as de-multiplexors or other circuits. To address this issue, the switching rates may be slowed in certain circuits by adding resistance and/or capacitance, thus raising the RC time constant and slowing the switching times to reduce the high frequency components. Alternatively or in addition to, an EMI shield can be placed over some or all of the display driving circuitry to shield the antenna from high frequency interference.

Abstract: A transistor that may be used in electronic displays to selectively activate one or more pixels. The transistor includes a metal layer, a silicon layer deposited on at least a portion of the metal layer, the silicon layer includes an extension portion that extends a distance past the metal layer, and at least three lightly doped regions positioned in the silicon layer. The at least three lightly doped regions have a lower concentration of doping atoms than other portions of the silicon layer forming the transistor.

Abstract: A display may have a thin-film-transistor layer with a substrate layer. A layer of dielectric may be formed on the substrate layer and may have an upper surface and a lower surface. The thin-film-transistor layer may include an array of display pixels. Data lines and gate lines may provide signals to the display pixels. Gate driver circuitry in an inactive peripheral portion of the display may include a gate driver circuit for each gate line. The gate driver circuits may include thin-film transistors that are formed on the upper surface of the layer of dielectric. Signal lines such as a gate low line, a gate routing line coupled between the gate driver circuits, and a common electrode line may be formed from two or more layers of metal to reduce their widths or may be embedded within the dielectric layer between the upper and lower surfaces under the thin-film transistors.

Abstract: Methods and devices for shielding displays from electrostatic discharge (ESD) are provided. In one example, a display of an electronic device may include a high resistivity shielding layer configured to protect electrical components from static charges. The display may also include a conductive layer electrically coupled to the high resistivity shielding layer and configured to decrease a discharge time of static charges from the high resistivity shielding layer. The display may include a grounding layer and a conductor electrically coupled between the conductive layer and the grounding layer to direct static charges from the conductive layer to the grounding layer.