Abstract:
A display may have an array of pixels. Display driver circuitry may supply data and control signals to the pixels. Each pixel may have seven transistors, a capacitor, and a light-emitting diode such as an organic light-emitting diode. The seven transistors may receive control signals using horizontal control lines. Each pixel may have first and second emission enable transistors that are coupled in series with a drive transistor and the light-emitting diode of that pixel. The first and second emission enable transistors may be coupled to a common control line or may be separately controlled so that on-bias stress can be effectively applied to the drive transistor. The display driver circuitry may have gate driver circuits that provide different gate line signals to different rows of pixels within the display. Different rows may also have different gate driver strengths and different supplemental gate line loading structures.
Abstract:
A display may have an array of pixels. The pixels may have color filter elements such as red, green, and blue color filter elements. A layer of opaque material may be used to form a black matrix. The black matrix may have openings that receive the color filter elements. A backlight unit may produce backlight illumination for the display. A reflector layer may be interposed between the black matrix and the backlight unit. The reflector layer may have openings aligned with the openings in the black matrix and the color filter elements and may overlap the black matrix. Some of the backlight from the backlight unit may pass through the color filter elements. Other backlight may by be recycled by being reflected off of the reflector layer, thereby enhancing backlight efficiency.
Abstract:
Improvement of visual uniformity of an integrated touch screen display is provided. A touch screen can include common electrodes separated by gaps in a Vcom layer. To improve visual non-uniformity in the display resulting from the gaps, a first set of semi-transparent dummy features (primary-dummy features) can be formed on a second layer at the locations of the gaps, and a second set of dummy features (supplementary-dummy features) can also be formed on the second layer or another layer to mitigate low spatial resolution of the primary-dummy features and/or non-uniform spacing of the primary-dummy features. In some examples, holes or slits can be formed in the Vcom layer at areas of the supplementary-dummy features to further improve visual uniformity.
Abstract:
A 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. A passivation layer may be formed on the thin-film transistor layers. An oxide liner may be formed on the passivation layer. A first low-k dielectric layer may be formed on the oxide liner. A second low-k dielectric layer may be formed on the first low-k dielectric layer. A common voltage electrode and associated storage capacitance may be formed on the second low-k dielectric layer. Thin-film transistor gate structures may be formed in the passivation layer. Conductive routing structures may be formed on the oxide liner, on the first low-k dielectric layer, and on the second low-k dielectric layer. The use of routing structures on the oxide liner reduces overall routing resistance and enables interlaced metal routing, which can help reduce the inactive border area outside the active display regions.
Abstract:
Devices and methods for increasing the aperture ratio and providing more precise gray level control to pixels in an active matrix organic light emitting diode (AMOLED) display are provided. By way of example, one embodiment includes disposing a gate insulator between a gate of a driving thin-film transistor and a gate of a circuit thin-film transistor. The improved structure of the display facilitates a higher voltage range for controlling the gray level of the pixels, and may increase the aperture ratio of the pixels.
Abstract:
A display may have an array of pixels. Display driver circuitry may supply data and control signals to the pixels. Each pixel may have seven transistors, a capacitor, and a light-emitting diode such as an organic light-emitting diode. The seven transistors may receive control signals using horizontal control lines. Each pixel may have first and second emission enable transistors that are coupled in series with a drive transistor and the light-emitting diode of that pixel. The first and second emission enable transistors may be coupled to a common control line or may be separately controlled so that on-bias stress can be effectively applied to the drive transistor. The display driver circuitry may have gate driver circuits that provide different gate line signals to different rows of pixels within the display. Different rows may also have different gate driver strengths and different supplemental gate line loading structures.
Abstract:
A display may have an array of pixels. Display driver circuitry may supply data and control signals to the pixels. Each pixel may have seven transistors, a capacitor, and a light-emitting diode such as an organic light-emitting diode. The seven transistors may receive control signals using horizontal control lines. Each pixel may have first and second emission enable transistors that are coupled in series with a drive transistor and the light-emitting diode of that pixel. The first and second emission enable transistors may be coupled to a common control line or may be separately controlled so that on-bias stress can be effectively applied to the drive transistor. The display driver circuitry may have gate driver circuits that provide different gate line signals to different rows of pixels within the display. Different rows may also have different gate driver strengths and different supplemental gate line loading structures.
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:
Devices and methods for increasing the aperture ratio and providing more precise gray level control to pixels in an active matrix organic light emitting diode (AMOLED) display are provided. By way of example, one embodiment includes disposing a gate insulator and an interlayer dielectric material between a gate electrode of a thin-film transistor of a driving circuit and a channel of the thin-film transistor. The improved structure of the driving circuit facilitates a higher voltage range for controlling the gray level of the pixels, and may increase the aperture ratio of the pixels.
Abstract:
A display may have an array of pixels. Display driver circuitry may supply data and control signals to the pixels. Each pixel may have seven transistors, a capacitor, and a light-emitting diode such as an organic light-emitting diode. The seven transistors may receive control signals using horizontal control lines. Each pixel may have first and second emission enable transistors that are coupled in series with a drive transistor and the light-emitting diode of that pixel. The first and second emission enable transistors may be coupled to a common control line or may be separately controlled so that on-bias stress can be effectively applied to the drive transistor. The display driver circuitry may have gate driver circuits that provide different gate line signals to different rows of pixels within the display. Different rows may also have different gate driver strengths and different supplemental gate line loading structures.