Patent application number | Description | Published |
20150053935 | Organic Light-Emitting Diode Displays With Semiconducting-Oxide and Silicon Thin-Film Transistors - 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. | 02-26-2015 |
20150109276 | Organic Light Emitting Diode Displays with Improved Driver Circuitry - 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. | 04-23-2015 |
20150109279 | Organic Light Emitting Diode Displays with Improved Driver Circuitry - 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. | 04-23-2015 |
20150145849 | Display With Threshold Voltage Compensation Circuitry - 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 compensation and programming operations. Each display pixel may have five p-type transistor and two capacitors. One of the five p-type transistors may serve as the drive transistor and may be compensated using the remaining four of the p-type transistors and the two capacitors. A first of the capacitors may be coupled between the gate and source of the drive transistor. A second of the capacitors may have a terminal coupled to the source. Alternatively, each display pixel may have six p-type transistors and a single capacitor. The six p-type transistors may include a drive transistor having a gate coupled to the capacitor. | 05-28-2015 |
20150206931 | Organic Light-Emitting Diode Display with Bottom Shields - 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. | 07-23-2015 |
20150268775 | Flexible Displays with Strengthened Pad Area - An electronic device may have a flexible display with portions that can be bent. The display may include an array of display pixels in an active area. Contact pads may be formed in an inactive area of the display. Display circuitry in the active area may exhibit a given stack height, whereas display circuitry in the inactive area may exhibit a stack height that is less than the given stack height. In particular, the contact pads may be formed directly on a multi-buffer layer that sits directly on a flexible display substrate. Passivation material may be selectively formed only at the edges of the contact pad on the multi-buffer layer. The multi-buffer layer may be formed at a distance from the edge of the flexible display substrate to minimize cracking in the multi-buffer layer. | 09-24-2015 |
20150275351 | Evaporation Tool - An evaporation tool is provided that has an elongated evaporation source with elongated edges that run parallel to a longitudinal axis and shorter edges that run perpendicular to the longitudinal axis. The evaporation source has multiple evaporation sources formed by respective source orifices through which material is evaporated. An evaporation control structure is mounted to the evaporation source to enhance the directionality of evaporated material. A shadow mask is provided that has a rectangular frame for supporting a metal mask layer with a pattern of openings. The evaporation control structure ensures that the evaporated material from the source is evaporated towards the shadow mask. Angled walls attached to the elongated edges, a series of vertical walls that extend between the angled walls in the evaporation control structure, and aligned vertical wall extensions on the frame of the shadow mask are used to block evaporated material following angled trajectories. | 10-01-2015 |
20150379938 | Organic Light-Emitting Diode Display With Reduced Lateral Leakage - A display may have an array of pixels. Each pixel may have a light-emitting diode that emits light under control of a drive transistor. The organic light-emitting diodes may have a common cathode layer, a common electron layer, individual red, green, and blue emissive layers, a common hole layer, and individual anodes. The hole layer may have a hole injection layer stacked with a hole transport layer. Pixel circuits for controlling the diodes may be formed from a layer of thin-film transistor circuitry on a substrate. A planarization layer may cover the thin-film transistor layer. Lateral leakage current between adjacent diodes can be blocked by shorting the common hole layer to a metal line such as a bias electrode that is separate from the anodes. The metal line may be laterally interposed between adjacent pixels and may be formed on the planarization layer or embedded within the planarization layer. | 12-31-2015 |