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 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: 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: 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 method is provided for fabricating thin-film transistors (TFTs) for an LCD having an array of pixels. The method includes depositing a first photoresist layer over a portion of a TFT stack. The TFT stack includes a conductive gate layer, and a semiconductor layer. The method also includes doping the exposed semiconductor layer with a first doping dose. The method further includes etching a portion of the conductive gate layer to expose a portion of the semiconductor layer, and doping the exposed portion of the semiconductor layer with a second doping dose. The method also includes removing the first photoresist layer, and depositing a second photoresist layer over a first portion of the doped semiconductor layer in an active area of the pixels to expose a second portion of the doped semiconductor layer in an area surrounding the active area.

Abstract: A TFT stack for a liquid crystal display is provided. The TFT stack includes a silicon layer that includes a heavily doped region, a non-doped region, and a lightly doped region between the heavily doped region and the non-doped region. The heavily doped region is hydrogenated. The TFT stack also includes an insulation layer that includes a first portion formed over the lightly doped region and a second portion disposed over the non-doped region and a gate metal electrode layer formed over the second portion of the non-doped region. The TFT stack also includes a first dielectric layer disposed over the gate metal electrode and over the first portion of the insulation layer. The heavily doped region is hydrogenated to reduce the dependence of the capacitance between the gate metal electrode and the conductive layer Cgd upon a bias voltage being applied between the gate metal electrode and the conductive layer.

Abstract: A method is provided for fabricating thin-film transistors (TFTs) for an LCD having an array of pixels. The method includes depositing a first photoresist layer over a portion of a TFT stack that includes a conductive gate layer, and a semiconductor layer. The method also includes doping the exposed semiconductor layer with a first doping dose. The method further includes etching a portion of the conductive gate layer to expose a portion of the semiconductor layer, and doping the exposed portion of the semiconductor layer with a second doping dose. The method also includes depositing a second photoresist layer over a first portion of the doped semiconductor layer in an active area of the pixels to expose a second portion of the doped semiconductor layer in an area surrounding the active area, and doping the second portion of the doped semiconductor layer with a third doping dose.

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: With respect to liquid crystal display inversion schemes, a large change in voltage on a data line can affect the voltages on adjacent data lines due to capacitive coupling between data lines. The resulting change in voltage on these adjacent data lines can give rise to visual artifacts in the data lines' corresponding sub-pixels. Various embodiments of the present disclosure serve to prevent or reduce persisting visual artifacts by offsetting their effects or by distributing their presence among different colored sub-pixels. In some embodiments, this may be accomplished by using different write sequences during the update of a row of pixels.

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 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: Gate driver circuitry that controls an array of display elements is described. The gate driver circuitry has gate drivers that apply a control pulse to each of a number of gate lines in sequence, from a previous gate line to a current gate line, during a frame interval in which the array of display elements is filled with pixel values. Each gate driver has a latch stage followed by an output stage. The output stage is coupled to drive a current gate line, and the latch stage is coupled to drive a) a first hold circuit that holds the current gate line at a predetermined voltage, and b) a second hold circuit that holds a previous gate line at a predetermined voltage. 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: Display ground plane structures may contain slits. Image pixel electrodes in the display may be arranged in rows and columns. Image pixels in the display may be controlled using gate lines that are associated with the rows and data lines that are associated with the columns. An electric field may be produced by each image pixel electrode that extends through a liquid crystal layer to an associated portion of the ground plane. The slits in the ground plane may have a slit width. Data lines may be located sufficiently below the ground plane and sufficiently out of alignment with the slits to minimize crosstalk from parasitic electric fields. A three-column inversion scheme may be used when driving data line signals into the display, so that pairs of pixels that straddle the slits are each driven with a common polarity. Gate line scanning patterns may be used that enhance display uniformity.

Abstract: Common electrodes (Vcom) of integrated touch screens can be segmented into electrically isolated Vcom portions that can be operated as drive lines and/or sense lines of a touch sensing system. The touch screen can include high-resistivity connections between Vcom portions. The resistivity of the high-resistivity connections can be high enough so that touch sensing and image display can be performed by the touch screen, and the high-resistivity connections can provide an added functionality by allowing a charge build up on one of the Vcom portions to be spread to other Vcom portions and/or discharged from system by allowing charge to leak through the high-resistivity connections. In this way, for example, visual artifacts that result from charge build up on a Vcom portion can be reduced or eliminated.

Abstract: Display ground plane structures may contain slits. Image pixel electrodes in the display may be arranged in rows and columns. Image pixels in the display may be controlled using gate lines that are associated with the rows and data lines that are associated with the columns. An electric field may be produced by each image pixel electrode that extends through a liquid crystal layer to an associated portion of the ground plane. The slits in the ground plane may have a slit width. Data lines may be located sufficiently below the ground plane and sufficiently out of alignment with the slits to minimize crosstalk from parasitic electric fields. A three-column inversion scheme may be used when driving data line signals into the display, so that pairs of pixels that straddle the slits are each driven with a common polarity. Gate line scanning patterns may be used that enhance display uniformity.

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.