| Patent application number | Description | Published |
| 20080203930 | Electroluminescent Display Devices - An active matrix display device comprises an array of display pixels provided over a common substrate. Each pixel has a voltage-programmed current source circuit, a drive transistor and a light sensitive device for sensing the display element light output. The light sensitive device provides a current dependent on the display element output, and the light sensitive device and the current source circuit define a feedback control loop which controls the voltage provided to the gate of the drive transistor. This pixel circuit uses a current source circuit to provide a gate voltage to a drive transistor. This enables the current source circuit to operate at low current levels, and therefore under low voltage stress. | 08-28-2008 |
| 20080212000 | Colour Active Matrix Displays - A method of manufacturing a colour active matrix display device comprises forming islands over a rigid carrier substrate, forming a plastic substrate over the rigid carrier substrate, forming an array of pixel circuits over the plastic substrate and forming a display layer over the array of pixel circuits. The rigid carrier substrate is then released from the plastic substrate and the plastic substrate then has channels defined by the islands. These are filled to define colour filter portions. The formation of a plastic substrate on a rigid carrier, with the use of a subsequent lift off process, enables the circuit arrays to be made on very thin plastic sheets. The colour filters can then be made on the outside of the LC cell. Depressions are formed in the plastic substrate registered to the circuit array, and these are filled in with colour filter material, for example by ink jet printing. | 09-04-2008 |
| 20090015521 | ACTIVE MATRIX DISPLAY DEVICES - An active matrix display device stores a transistor drive voltage on a storage capacitor ( | 01-15-2009 |
| 20090015578 | LIGHT EMITTING DISPLAY DEVICES - An active matrix electroluminescent display device has power supply lines ( | 01-15-2009 |
| 20090128534 | ACTIVE MATRIX DISPLAY DEVICES - A method of driving an active matrix display device comprises, for each pixel, driving a current through a drive transistor ( | 05-21-2009 |
| 20090174699 | ELECTROLUMINESCENT DISPLAY DEVICES AN ACTIVE MATRIX - An active matrix EL display has first and second capacitors connected in series between the gate and source or drain of a pixel drive transistor. A data input to the pixel is provided to the junction between the first and second capacitors thereby to charge the second capacitor to a voltage derived from the pixel data voltage, and a voltage derived from the drive transistor threshold voltage being stored on the first capacitor. A discharge transistor is connected between the junction between the first and second capacitors and a common line for all pixels of the display. This device uses a common line as a discharge sink/source for the threshold voltage measurement operation. By avoiding the use of a data line for this purpose, the pixel can be in a non-addressed state when the threshold measurement takes place. | 07-09-2009 |
| 20090243498 | Electroluminescent display devices - The pixels of an active matrix display device have a current-driven light emitting display element, a drive transistor for driving a current through the display element, a storage capacitor for storing a pixel drive voltage to be used for addressing the drive transistor, a light-dependent device for detecting the brightness of the display element, and driver circuitry for providing data signals to the pixel external to the pixel array. This provides a pixel with optical feedback to compensate for display element ageing. The driver circuitry has a processing means for processing the feedback brightness signals and derives from them a threshold voltage for the drive transistor of the pixel as well as information relating to the performance of the display element, for ageing compensation. | 10-01-2009 |
| 20100177075 | ELECTROLUMINESCENT DISPLAY DEVICES - An active matrix LED display device uses optical feedback for controlling the pixel drive transistors ( | 07-15-2010 |
| 20100265440 | COLOUR ACTIVE MATRIX DISPLAYS - A method of manufacturing a colour active matrix display device comprises forming islands over a rigid carrier substrate, forming a plastic substrate over the rigid carrier substrate, forming an array of pixel circuits over the plastic substrate and forming a display layer over the array of pixel circuits. The rigid carrier substrate is then released from the plastic substrate and the plastic substrate then has channels defined by the islands. These are filled to define colour filter portions. The formation of a plastic substrate on a rigid carrier, with the use of a subsequent lift off process, enables the circuit arrays to be made on very thin plastic sheets. The colour filters can then be made on the outside of the LC cell. Depressions are formed in the plastic substrate registered to the circuit array, and these are filled in with colour filter material, for example by ink jet printing. | 10-21-2010 |
| 20110043548 | ELECTROLUMINESCENT DISPLAY DEVICE - In an active matrix electroluminescent display device, an overall brightness level of an image to be displayed in a frame period is determined. A drive transistor of each pixel is controlled in dependence on an input drive signal for the pixel and on the overall brightness level, for example using a signal processor ( | 02-24-2011 |
| 20110109670 | METHOD AND DEVICE FOR DRIVING AN ACTIVE MATRIX DISPLAY PANEL - An active matrix display panel comprises a substrate, an array of pixel circuits being arranged in a matrix of at least one column and a plurality of rows on the substrate, each pixel circuit comprising a light-emitting element, capable of emitting light of an intensity determined by the value of a current passed through it, and at least one column line, each column line arranged to conduct a reference current, provided by a current driving circuit, when connected to the panel. The pixel circuits in a column are divided into a plurality of groups of at least one pixel circuit. The active matrix display panel comprises at least one current mirror circuit associated with a first group, comprising a first current mirror, arranged to mirror a reference current flowing through a column line to a first current mirror output. Each pixel circuit in the first group comprises at least a first current-memory stage, having an output terminal connected to the light-emitting element, wherein the first current-memory stage is capable of drawing a current determined at least partly by the current mirrored to the first current mirror output through the output terminal. Each current mirror circuit comprises at least one additional current mirror, arranged to mirror a reference current flowing through an associated column line to an additional current mirror output, wherein each additional current mirror output is connected in parallel to the first current mirror output. | 05-12-2011 |