Joled Inc.

Panasonic Corporation

Kouhei Ebisuno

Shinya Ono

Toshiyuki Kato

Hitoshi Tsuge

Masafumi Matsui

Yosuke Izawa

Arinobu Kanegae

Takashi Osako

Yasuo Segawa

Tetsurou Nakamura

Shigeo Homura

A display device comprising pixel circuits arranged in a matrix, in which each of the pixel circuits includes: an EL element; a capacitor for storing voltage; a drive transistor that provides, to the EL element, a current corresponding to the voltage stored in the capacitor to cause the EL element to emit light; a voltage supplier that applies a reference voltage to the drive transistor in an initialization period, and applies a reverse bias voltage to the drive transistor in a predetermined period before the initialization period, the reference voltage being higher than a threshold voltage of the drive transistor and providing a forward bias between the gate and source electrodes of the drive transistor, the initialization period being a period for initializing the pixel circuit, the reverse bias voltage providing a reverse bias between the gate and source electrodes of the drive transistor.

Display device and driving method

By a drive method, for each of a plurality of display pixels each including an EL element, a capacitor, a drive transistor, an enable switch, and a switch, a period Tis started by switching only the enable switch to an electrically conductive state before a period Tin which the drive transistor is initialized, and the period Tfollowing the period Tis started by switching the switch to an electrically conductive state. The period Tis longer than a period Tin which a threshold voltage of the drive transistor is compensated.

Drive method and display device

An image display apparatus includes: a first pixel circuit including a driving transistor that drives a light emitting element and includes a gate electrode on a substrate, a semiconductor layer and a pair of source-drain electrodes; a second pixel circuit disposed adjacent to the first pixel circuit; a second pixel electrode that is formed above the second pixel circuit and is electrically connected to one of the pair of source-drain electrodes of the driving transistor of the first pixel circuit; and a top metal electrode that is electrically connected to one of the pair of source-drain electrodes and is formed to cover at least an entire channel region of the semiconductor layer from above.

Image display apparatus

A display device includes a voltage drop amount calculating circuit that regulates a power source voltage, a power wire network in the organic EL display unit includes a row-wise resistance component Rah and a column-wise resistance component Rav, and the voltage drop amount calculating circuit divides the organic EL display unit into blocks each made up of pixels in Xv rows and Xh columns, and sets, for each of the blocks, a row-wise resistance component Rah' to a value obtained by multiplying the resistance component Rah by (Xh/Xv), and sets, for each of the blocks, a column-wise resistance component Rav&#x2032; to a value obtained by multiplying the resistance component Rav by (Xv/Xh), thereby estimating a distribution, for the respective blocks, of amounts of voltage drop which occurs in the power wire, and regulates, based on the distribution, a voltage to be supplied to the display unit.

Display device and method of driving the same

An organic electroluminescence (EL) display panel includes an anode electrode formed above a bank and formed opposite to a plurality of cathode electrodes, and a charge functional layer commonly formed for each of the organic light-emitting layers across a plurality of aperture areas formed in the bank. An end portion of the anode electrode and an end portion of the charge functional layer are provided above the bank located adjacent to a boundary between a display region and a peripheral region of a display region.

Organic electroluminescence display panel and organic electroluminescence display apparatus

An organic electroluminescence (EL) display panel includes a cathode electrode formed above a bank and formed opposite to a plurality of anode electrodes, and a charge functional layer commonly formed for each of the organic light-emitting layers across a plurality of aperture areas formed in the bank. An end portion of the cathode electrode and an end portion of the charge functional layer are provided above the bank located adjacent to a boundary between a display region and a peripheral region of a display region.

Pixel circuits of a display device each include: a drive transistor including one of a source and drain connected to a power source line; a capacitive element including a first terminal connected to a gate of the drive transistor; a switching element which switches conduction/non-conduction between a second terminal of the capacitive element and a data line; a switching element which switches conduction/non-conduction between the second terminal of the capacitive element and the source of the drive transistor; a switching element which switches conduction/non-conduction between the first terminal of the capacitive element and a reference voltage line; a light-emitting element including a first terminal connected to the other of the source and drain of the drive transistor and a second terminal connected to another power source line. The reference voltage line provides a forward bias voltage larger than a threshold voltage across the gate and source of the drive transistor.

Display device and method of controlling the same

A display device includes a lower wiring layer, an interlayer insulating layer, and an upper wiring layer. The lower wiring layer includes first partial electrode portions, first cuttable portions, and first openings; the upper wiring layer includes second partial electrode portions, second cuttable portions, and second openings. The first partial electrode portions and the second partial electrode portions are disposed in overlapping positions in the stacking direction; all the first cuttable portions and the second openings are disposed in overlapping positions in the stacking direction; all the second cuttable portions and the first openings are disposed in overlapping positions in the stacking direction.

Display device and method of manufacturing display device

A display device has a plurality of arrayed display pixels. A drive transistor includes a first gate electrode and supplies the current corresponding to a level of a luminance signal to the luminescence element. A switching transistor includes a source electrode, a drain electrode, a second gate electrode and a semiconductor layer. The semiconductor layer is faced with the second gate electrode and has, in a channel width direction perpendicular to a channel length direction of the switching transistor, a channel region with a first width and a remainder region with a second width larger than the first width. The source electrode or the drain electrode is connected to the first gate electrode. The source electrode and the drain electrode are provided on the semiconductor layer at an interval. The second gate electrode overlaps, in a plan view, the channel region entirely and the remainder region at least partially.

Display device

A panel for a display device includes a display unit, an electrostatic protection wire, a wire being connected to the display pixels, an electrostatic protection circuit, and an electrostatic protection circuit control line. The display unit includes a plurality of display pixels. The electrostatic protection wire is connected to a test pad, the test pad being provided to receive a test signal. The electrostatic protection circuit connects the electrostatic protection wire and the wire connected to the display pixels. The electrostatic protection circuit includes a back-gate-type transistor that has a gate electrode, a drain electrode being short-circuited with the gate electrode, and a back-gate electrode. The electrostatic protection circuit control line includes a first end and a second end, the first end being connected to the back-gate electrode of the back-gate-type transistor.

Panel for display device, display device, and method for testing panel for display device

In an organic electroluminescence (EL) display apparatus, a bus line is provided on an edge of a display unit in a display panel. A feedback circuit unit is provided outside of the bus line, and an output voltage of the feedback circuit unit is applied to a connecting part on the bus line. To the feedback circuit unit, a reference voltage from a reference voltage generating unit is applied, a power supply voltage from a power supply unit is supplied, and a monitoring voltage from the connecting part on the bus line is fed back. The feedback circuit unit includes a switching control circuit and a transistor, and controls, using a feedback, the output voltage by supplying or blocking the power supply voltage to an output terminal, so that a voltage at the connecting point is equal to a target voltage determined by the reference voltage.

Organic EL display apparatus

Display device includes: a power supplying unit which outputs at least a high-side or low-side output potential; an organic EL display unit which includes pixels and receives power supply from the power supplying unit; two or more detecting lines for transmitting a high-side or low-side applied potential applied to two or more pixels; a relay unit which outputs the high-side or low-side applied potentials transmitted by the detecting lines, to output lines fewer in number than the detecting lines; and a regulating unit which regulates at least the high-side or low-side output potential to be outputted by the power supplying unit, such that any one of potential difference between a reference potential and the high-side applied potential from the relay unit, potential difference between the reference potential and the low-side applied potential, and potential difference between the high-side applied potential and the low-side applied potential reaches a predetermined potential difference.

Display device and display device driving method for causing reduction in power consumption

An organic electroluminescence (EL) display panel includes a cathode electrode formed above a bank and formed opposite to a plurality of anode electrodes, and a charge functional layer commonly formed for each of the organic light-emitting layers across a plurality of aperture areas formed in the bank. A distance from the center of the display region to the end of the cathode electrode is shorter than a distance from the center of the display region to the end of the charge functional layer.

An organic electroluminescence (EL) display panel includes an anode electrode formed above a bank and formed opposite to a plurality of cathode electrodes, and a charge functional layer commonly formed for each of the organic light-emitting layers across a plurality of aperture areas formed in the bank. A distance from the center of the display region to the end of the anode electrode is shorter than a distance from the center of the display region to the end of the charge functional layer.

A display device includes: a high-side potential variable-voltage source which outputs a high-side output potential and a low-side potential variable-voltage source which outputs a low-side output potential; an organic EL display unit in which pixels are arranged; a high-side potential difference detecting circuit which detects a high-side potential applied to a first pixel and a low-side potential difference detecting circuit which detects a low-side potential applied to a second pixel; a high-side potential voltage margin setting unit and a low-side potential voltage setting unit which regulate the output potential of the high-side potential variable-voltage source and the low-side potential variable-voltage source to set a potential difference between the high-side potential of the first pixel and a reference potential to a predetermined potential difference and set a potential difference between the low-side potential of the second pixel and a reference potential to a predetermined potential difference; and a signal processing circuit.

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Kyoto, Japan

Kouhei Ebisuno