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 display may have an array of pixels controlled by display driver circuitry. The pixels may have pixel circuits. In liquid crystal display configurations, each pixel circuit may have an electrode that applies electric fields to an associated portion of a liquid crystal layer. In organic light-emitting diode displays, each pixel circuit may have a drive transistor that applies current to an organic light-emitting diode in the pixel circuit. The pixel circuits and display driver circuitry may have thin-film transistor circuitry that includes transistor such as silicon transistors and semiconducting-oxide transistors. Semiconducting-oxide transistors and silicon transistors may be formed on a common substrate. Semiconducting-oxide transistors may have polysilicon layers with doped regions that serve as gates. Semiconducting-oxide channel regions overlap the gates.

Abstract: A touch screen is disclosed. The touch screen can comprise a substrate having a first surface upon which a touch or proximity event is to be detected, and a second surface that opposes the first surface, and a touch sensor electrode and a first display pixel including a first display pixel TFT formed on the second surface of the substrate. The first touch sensor electrode can be disposed between the second surface of the substrate and the first display pixel TFT, and the first touch sensor electrode can be configured to detect the touch or proximity event. In some examples, the substrate can comprise a TFT glass substrate. In some examples, the touch screen can comprise a first touch sensor routing electrically coupled to the first touch sensor electrode, wherein the first touch sensor routing is disposed between the second surface of the substrate and the first display pixel TFT.

Abstract: A display may have an array of organic light-emitting diode display pixels. Each display pixel may have a light-emitting diode that emits light under control of a drive transistor. Each display pixel may also have control transistors for compensating and programming operations. The array of display pixels may have rows and columns. Row lines may be used to apply row control signals to rows of the display pixels. Column lines (data lines) may be used to apply display data and other signals to respective columns of display pixels. A bottom conductive shielding structure may be formed below each drive transistor. The bottom conductive shielding structure may serve to shield the drive transistor from any electric field generated from the adjacent row and column lines. The bottom conductive shielding structure may be electrically floating or coupled to a power supply line.

Abstract: A display may have an array of pixels controlled by display driver circuitry. The display driver circuitry may supply the pixels with data signals over data lines in columns of the pixels and may supply the pixels with gate line signals over gate lines in rows of the pixels. The display driver circuitry may have a display driver integrated circuit located on one of the edges of the display. The display driver circuitry may also have gate driver integrated circuits that extend along opposing edges of the display to form a pair of shift registers. Conductive lines in a display substrate may be coupled to opposing ends of the shift registers and to intermediate locations within the shift registers to minimize delays in distributing a gate high voltage signal from the display driver integrated circuit to the shift registers.

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: A display may have an array of light-emitting diode pixels or pixels containing portions of a liquid crystal layer to which electric fields are applied using electrodes. A pixel with a light-emitting diode may have a drive transistor coupled in series with the light-emitting diode. A storage capacitor may be coupled to a gate of the drive transistor. A pixel with a liquid crystal portion may have a storage capacitor coupled to a given one of the electrodes in that pixel. Switching circuitry in each pixel may be used to load data from a data line into the storage capacitor of the pixel. The switching circuitry may include a semiconducting-oxide transistor coupled to an associated data line and a series-connected silicon transistor that is coupled to the storage capacitor.

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: A display may have an array of organic light-emitting diode display pixels. Each display pixel may have a light-emitting diode that emits light under control of a thin-film drive transistor. Each display pixel may have thin-film transistors and capacitor structures that form a circuit for compensating the drive transistor for threshold voltage variations. The capacitor structures may be formed from interleaved stacked conductive plates. The conductive plates may be formed from layers of material that are used in forming the drive transistor and other thin-film transistors such as a semiconductor layer, a first metal layer, a second metal layer, a third metal layer, and interposed dielectric layers.

Abstract: A display may have upper and lower display layers. A layer of liquid crystal material may be interposed between the upper and lower display layers. The display layers may have substrates. The display layers may include a color filter layer having an array of color filter elements on a glass substrate and a thin-film transistor layer having a layer of thin-film transistor circuitry on a glass substrate. Dielectric layers within the display layers such as dielectric layers within the thin-film transistor layer may have differing indices of refraction. Reflections and color shifts due to index of refraction discontinuities may be minimized by interposing graded index dielectric layers between adjacent layers with different indices. The graded index layers may be formed from structures with a continuously varying index of refraction or structures with a step-wise varying index of refraction.

Abstract: A display may have a color filter layer and a thin-film transistor layer. A liquid crystal layer may be located between the color filter layer and the thin-film transistor layer. The color filter layer may have an array of color filter elements on a transparent substrate. The array of color filter elements may include more than three colors. Colored photoimageable polymer layers may be combined to form some of the color filter elements. The color filter may have cyan, magenta, and yellow color filter elements each formed from a respective single layer of cyan, magenta, and yellow polymer and may have blue elements formed by overlapping cyan and magenta polymer, green elements formed by overlapping cyan and yellow polymer, and red elements formed by overlapping magenta and yellow polymer. Filters with white elements may also be provided.

Abstract: An electronic device may have a flexible display with portions that are bent along a bend axis. The display may have display circuitry such as an array of display pixels in an active area. Contact pads may be formed in an inactive area of the display. Signal lines may couple the display pixels to the contact pads. The signal lines may overlap the bend axis in the inactive area of the display. During fabrication, an etch stop may be formed on the display that overlaps the bend axis. The etch stop may prevent over etching of dielectric such as a buffer layer on a polymer flexible display substrate. A layer of polymer that serves as a neutral stress plane adjustment layer may be formed over the signal lines in the inactive area of the display. Upon bending, the neutral stress plane adjustment layer helps prevent stress in the signal lines.

Abstract: Fabrication of thin sheets of glass or other substrate material for use in devices such as touch sensor panels is disclosed. A pair of thick glass sheets, typically with thicknesses of 0.5 mm or greater each, may each be patterned with thin film on a surface, sealed together to form a sandwich with the patterned surfaces facing each other and spaced apart by removable spacers, either or both thinned on their outside surfaces to thicknesses of less than 0.5 mm each, and separated into two thin glass sheets. A single thick glass sheet, typically with a thickness of 0.5 mm or greater, may be patterned, covered with a protective layer over the pattern, thinned on its outside surface to a thickness of less than 0.5 mm, and the protective layer removed. This thinness of less than 0.5 mm may be accomplished using standard LCD equipment, despite the equipment having a sheet minimum thickness requirement of 0.5 mm.

Abstract: A display may have a thin-film transistor layer and color filter layer. The display may have an active area and an inactive border area. Light blocking structures in the inactive area may prevent stray backlight from a backlight light guide plate from leaking out of the display. The thin-film transistor layer may have a clear substrate, a patterned black masking layer on the clear substrate, a clear planarization layer on the black masking layer, and a layer of thin-film transistor circuitry on the clear planarization layer. The black masking layer may be formed from black photoimageable polyimide. The clear planarization layer may be formed from spin-on glass. The light blocking structures may include a first layer formed from a portion of the black masking layer and a second layer such as a layer of black tape on the underside of the color filter layer.

Abstract: A liquid crystal display (LCD) is provided having a discontinuous electrode. In certain embodiments, different portions (such as finger- or slit-like extensions) of the discontinuous electrode may be at different depths relative to one another and/or may be of different widths relative to one another. Similarly, in other embodiments, the different portions of the discontinuous electrode may be spaced apart in a non-uniform manner.

Abstract: A display has an array of pixels controlled by display driver circuitry. Gate driver circuitry supplies gate line signals to rows of the pixels. The pixels may be liquid crystal display pixels. Each pixel may have a common electrode voltage terminal. The display may have a transparent conductive film that forms a common electrode voltage layer that overlaps that array and that is shorted to the common electrode voltage terminals of the pixels. Metal common electrode voltage lines may run across the transparent conductive film to reduce resistance. Metal common electrode voltage paths that are coupled to the metal common electrode voltage lines may run along the left and right edge of the display. Common electrode voltage compensation circuits may receive feedback from the metal common electrode voltage paths. There may be two or more common electrode voltage compensation circuits for both the left and right edges of the display.

Abstract: A display may have an array of pixels arranged in rows and columns. Display driver circuitry may be provided along an edge of the display. Data lines that are associated with columns of the pixels may be used to distribute data from the display driver circuitry to the pixels. Gate lines in the display may each have a horizontal straight portion that extends along a respective row of the pixels and may each have one or more non-horizontal segments such as zigzag segments. The non-horizontal portion of each gate line may be connected to the horizontal straight portion of the gate line by a via. The non-horizontal portions may each have portions that are overlapped by portions of the data lines. Dummy gate line structures may be provided on the display that are not coupled to any of the pixels in the display.

Abstract: A display device may include pixels and source lines that provide data line signals to the pixels. The display device may also include gate lines that provide gate signals to switches associated with the pixels. The display device may also include vertical gate lines disposed generally parallel to the source lines and coupled to the gate lines at cross point nodes. The display device may also include compensation lines, such that each compensation line is proximate to a respective vertical gate line. The compensation lines may transmit compensation signals having an opposite polarity as compared to respective gate signals to reduce or eliminate a kickback voltage on at least one of the plurality of pixels.

Abstract: A display may have upper and lower display layers. A layer of liquid crystal material may be interposed between the upper and lower display layers. The display layers may have substrates. A thin-film transistor layer may have a layer of thin-film transistor structures on a substrate such as a clear glass layer. A planarization layer may be formed on the thin-film transistor structures. A transparent conductive layer may be formed on the planarization layer. The display may have a dielectric layer on the transparent conductive layer. Pixels may be formed in the display layers. The pixels may include pixel electrodes having fingers. The fingers may be formed on the dielectric layer. Trenches in the dielectric layer may be formed between the fingers. The trenches may extend to the transparent conductive layer or may be formed only partway into the dielectric layer.

Abstract: A flexible display having an array of pixels or sub-pixels is provided. The display includes a flexible substrate and an array of thin film transistors (TFTs) corresponding to the array of pixels or sub-pixels on the substrate. The display also includes a first plurality of metal lines coupled to gate electrodes of the TFTs and a second plurality of metal lines coupled to source electrodes and drain electrodes of the TFTs. At least one of the first plurality of metal lines and the second plurality of metal lines comprises a non-stretchable portion in the TFT areas and a stretchable portion outside the TFT areas.