Apple Inc.

Young Bae Park

Shih Chang Chang

Vasudha Gupta

Jae Won Choi

John Z Zhong

Tsung-Ting Tsai

Chin-Wei Lin

Kyung Wook Kim

Chun-Yao Huang

Paul Stephen Drzaic

Cheng Kai Chen

Ming-Chin Hung

MinKyu Kim

Wei Chen

Jean-Pierre Simon Guillou

Zhibing Ge

Byung Duk Yang

Sang Ha Kim

Jungbae Kim

Ming Xu

Shawn Robert Gettemy

Chieh-Wei Chen

Cheng-Ho Yu

Sang Young Youn

Shih-Chang Chang

Kuo-Hua Sung

Zhen Zhang

Young Cheol Yang

Hao-Lin Chiu

Silvio Grespan

Brett W Degner

Dinesh C Mathew

Ting-Kuo Chang

Abbas Jamshidi Roudbari

Joshua G Wurzel

Szu-Hsien Lee

Koorosh Aflatooni

Yi Tao

Kyung-Wook Kim

Stephen S Poon

Minhyuk Choi

Shang-Chih Lin

Kwang Ohk Cheon

Damien S Boesch

Daisuke Nozu

Cheng Ho Yu

Da Yu

Chih Jen Yang

EnkhAmgalan Dorjgotov

Lalgudi Bhadrinarayana Visweswaran

ZhiFeng Zhan

Minkyu Kim

Cheng Chen

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.

Displays with silicon and semiconducting oxide thin-film transistors

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.

Displays with series-connected switching transistors

An electronic device may be provided with an organic light-emitting diode display. The display may include row driver circuitry that provides an emission control signal at an output terminal to display pixels. The emission control signals may enable or disable light emission by the pixels. The row driver circuitry may include a bootstrapping capacitor that stores charge for boosting a gate signal at an intermediate node for a pull-up transistor above a power supply voltage. The row driver circuitry may include a pull-down transistor coupled to the intermediate node. The source terminal of the pull-down transistor may be coupled to the output terminal or an additional pull-down transistor may be stacked with the pull-down transistor to reduce leakage current. Charge pump circuitry may be coupled to the intermediate node to ensure that the intermediate node is maintained at a voltage above the power supply voltage.

Organic light emitting diode displays with improved driver circuitry

A display may have an array of pixels formed from thin-film transistor circuitry. The thin-film transistor circuitry may include thin-film layers of dielectric, semiconductor, and metal on a dielectric substrate. Test structures may be formed around the periphery of the substrate to facilitate testing of the thin-film circuitry during manufacturing. The test structures may include test pads that are coupled to the thin-film circuitry by test lines extending from the thin-film circuitry. Following testing, the outermost portions of the display and the test pads on these display portions may be removed by cutting the substrate along a substrate cut line. The test lines may be formed from parallel lines that are shorted together, semiconductor layers, multiple layers of conductive material, and other structures that resist corrosion along the cut line.

Corrosion resistant test lines

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 levelvoltage higher than a minimum gray scale levelvoltage 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.

Gray scale inversion reduction or prevention in liquid crystal displays

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. The silicon transistors may be configured in a top gate arrangement. The oxide transistors may be configured in a top gate or a bottom gate arrangement. In one embodiment, source-drain contacts for the silicon and oxide transistors may be formed simultaneously. In another embodiment, the silicon and oxide thin-film transistor structures may be formed using at least three metal routing layers.

Organic light-emitting diode displays with silicon and semiconducting oxide thin-film transistors

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.

Displays with bent signal lines

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.

Organic light-emitting diode display with luminance control

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.

Pixel inversion artifact reduction

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.

Display with inactive area surrounded by active area

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Cupertino, CA, United States of America

Young Bae Park