Abstract: This disclosure generally relates to display driver circuits for electro-optic displays, and more particularly relates to circuits and methods for driving active matrix organic light emitting diode displays with greater efficiency.

Abstract: A display driver control circuitry and method for controlling a display driver for an electroluminescent display, the display comprising at least one substantially constant current generator for driving the display element, the control circuitry comprising: a drive voltage sensor for sensing a drive voltage on a first line in which the current is regulated by the constant current generator; a reference voltage generator for providing a reference voltage offset from a supply voltage provided from a supply line to the constant current generator; means for determining a difference between the reference voltage and the drive voltage and for generating an adjustment signal, and wherein a voltage controller is configured to adjust the supply voltage responsive to the adjustment signal.

Abstract: A current matching control apparatus for matching a plurality of current sources and a plurality of current sinks, the plurality of current sinks having a drive current value controlled by a drive processor in accordance with a reference control current and wherein each output of the plurality of current sinks are connected to a common output node; a feedback circuit having an input connected to the common output node and an output connected to the drive processor, wherein the feedback circuit is arranged to match a voltage at the common output node to a reference voltage by communicating a signal to the drive processor to adjust the reference control current.

Abstract: A method of driving an electro-optic display comprising providing a current source, digitally modulating the current source and generating a modulated digital signal, and converting the modulated digital signal into an effective analog drive signal so that the display pixels receive an effective analog drive current, wherein the internal capacitance of the electro-optic display smooths the digitally modulated signal and generates the effective analog drive signal.

Abstract: Display driver circuits for driving an organic light emitting diode display, particularly a passive matrix display with greater efficiency are described. The display includes at least one electroluminescent display element, and the driver includes at least one substantially constant current generator for driving the display element. The display driver control circuitry includes a drive voltage sensor for sensing a voltage on a first line in which the current is regulated by the constant current generator; and a voltage controller coupled to the drive voltage sensor for controlling the voltage of a supply for the constant current generator in response to said sensed voltage, and configured to control the supply voltage to increase the efficiency of said display driver.

Abstract: A passive matrix display comprising an array of diodes disposed between a plurality of anode lines and a plurality of cathode lines, wherein at least some of the diodes are emissive diodes which are orientated in a forward direction relative to the cathode and anode lines and others of the diodes are sensing diodes orientated in a reverse direction relative to the cathode and anode lines.

Abstract: This invention generally relates to apparatus and methods for driving passive, electro-optic displays with greater efficiency. The invention is particularly suitable for driving passive matrix organic light emitting diode displays.

Abstract: This invention generally relates to organic electronic devices and to methods for their fabrication. More particularly we will describe organic thin film transistor (TFT) structures and their fabrication. An organic electronic device, the device comprising: a substrate supporting a first electrode; a spacer structure over said substrate; a second electrode over said spacer structure and at a height above said first electrode; and a layer of organic semiconducting material over said first and second electrodes to provide a conducting channel between said first and second electrodes; and wherein a majority of said first electrode is laterally positioned to one side of said channel and a majority of said second electrode is laterally positioned to the other side of said channel.

Abstract: This invention generally relates to active matrix organic electro-optic devices and to related display driving methods. In embodiments the invention relates to top-emitting OLED (Organic Light Emitting Diode) displays including additional circuitry which may be employed for display driving or other functions. An active matrix organic electro-optic device, the device having a plurality of pixels and comprising a substrate bearing pixel interface circuitry for each of said pixels and organic material over said pixel interface circuitry, wherein said device is configured such that over at least a part of an area of said device said pixel interface circuitry is staggered with respect to said pixels such that a region under at least one of said pixels is incompletely occupied by said pixel interface circuitry, and wherein additional circuitry for said device is fabricated in said region incompletely occupied by said pixel interface circuitry.

Abstract: This invention relates to methods, apparatus, and computer program code for driving an active matrix display, in particular an organic light emitting diode (OLED) display, with reduced power consumption.

Abstract: Display driver circuits are described for driving organic light emitting diode displays, particularly passive matrix displays, with greater efficiency. The display drivers comprise a controllable current generator to provide a variable current drive output to an OLED display, the current generator comprising at least one bipolar transistor in series with the current drive output. The display brightness is adjustable by controlling the current generator to vary the current drive to the display. Preferably the bipolar transistor has an emitter terminal substantially directly connected to a power supply line of the driver to reduce losses in the driver. A corresponding method is also described. By employing a bipolar transistor current drive and varying display brightness by controlling the current an efficient driver-display combination is obtained.

Abstract: Display driver circuits are described for driving organic light emitting diode displays, particularly passive matrix displays with greater efficiency. Display driver control circuitry (506) comprises a frame memory interface (505) for reading data from a frame memory (504) for presentation on a passive matrix OLED display. A blank line identifier (507) identifies one or more substantially blank rows of pixels define by the data in the frame memory and the control circuitry (506) skips past these rows when the passive matrix display is addressed. When blank lines are skipped the apparent brightness of the remaining lines increases and thus preferably the control circuitry includes a power controller (505) for reducing a power supply to the display in proportion to the number of skipped lines. The invention is particularly suited to a display driver providing a controlled current drive.

Abstract: A top-emitting display apparatus is provided having a plurality of pixels, said apparatus comprising an anode formed on a substrate, a well-defining layer, the thickness of said well-defining layer being insufficient for it to serve as a spacer for an evaporation mask, an organic electroluminescent layer formed on the anode in each well of the well-defining layer to form said plurality of pixels, a layer of metal formed on the top surface of the well-defining layer, and a transparent cathode layer deposited such that it is formed both on the electroluminescent layer and the layer of metal on the top surface of the well-defining layer. A method for the manufacture of such an apparatus is also provided.

Abstract: Display driver circuits are described for driving organic light-emitting diode displays, particularly passive matrix displays, with greater efficiency. Display driver circuitry includes a frame memory interface for reading data from a frame memory for presentation on a passive matrix OLED display. A blank line identifier identifies one or more substantially blank rows of pixels defined by the data in the frame memory and the control circuitry skips past these rows when the passive matrix display is addressed. When blank lines are skipped the apparent brightness of the remaining lines increases and thus preferably the control circuitry includes a power-controller for reducing a power supply to the display in proportion to the number of skipped lines. The disclosed circuitry is particularly suited to a display driver providing a controlled current drive.

Abstract: Display driver circuitry for electro-optic displays, in particular active matrix displays using organic light emitting diodes. The circuitry includes a driver to drive an electro-optic element in accordance with a drive voltage, a photosensitive device optically coupled to the electro-optic display element to pass a current dependent upon illumination reaching the photosensitive device, a first control device coupled between the photosensitive device and a data line and responsive to a first control signal on a first control line to couple the photosensitive device to the data line, and a second control device coupled between the photosensitive device and the driver and responsive to a second control signal on a second control line to couple the photosensitive device to the driver. The circuit can be operated in a number of different modes and provides flexible control of an electro-display element such as an organic LED pixel.

Abstract: An organic light emissive device comprising: a first electrode; a second electrode; and an organic light emissive region between the first and second electrodes comprising an organic light emissive material which has a peak emission wavelength, wherein at least one of the electrodes is transparent and comprises a composite of a charge injecting metal and another material which is codepositable with the charge injecting metal, the other material having a different refractive index to that of the charge injecting metal and wherein the other material has a lower degree of quenching at the peak emission wavelength than the charge injecting metal whereby quenching of excitons by the at least one electrode is reduced, the charge injecting metal comprising either a low work function metal having a work function of no more than 3.5 eV or a high work function metal having a work function of no less than 4.5 eV.

Abstract: A device comprising an organic light emitting diode coupled to a cavity, said cavity containing an emitting species, said device being arranged such that light emitted from said organic light emitting diode is at least partially absorbed by the emitting species and re-emitted from the emitting species. The device may be arranged such that the emitting species acts as the gain media of a laser, and the organic light emitting diode may be arranged to pump the emitting species. Also provided is method of generating light, said method comprising: coupling an organic light emitting diode to a cavity, said cavity containing an emitting species, said organic light emitting diode and said cavity being arranged such that light emitted from said organic light emitting diode is at least partially absorbed by the emitting species; operating said organic light emitting diode to emit light which is at least partially absorbed by the emitting species; and re-emitting light from the emitting species.

Abstract: A method of driving a passive matrix multicolor electroluminescent display, the display comprising a plurality of pixels arranged in rows and columns, each said pixel comprising at least first and second sub-pixels having different respective first and second colors, the method comprising: driving groups of said pixels in turn to display a multicolor image frame, said driving of a group of pixels comprising driving first and second sub-groups of sub-pixels of respective said first and second colors; and wherein said driving further comprises driving a said group of pixels for a duration dependent upon a maximum drive level of a sub-pixel of a said sub-group.

Abstract: A light-emissive display comprising a substrate, a first electrode layer disposed over the substrate, a light-emissive layer disposed over the first electrode layer, and a second electrode layer disposed over the light-emissive layer, wherein the light-emissive layer is patterned to provide a plurality of discrete light-emissive regions, each discrete light-emissive region being a pixel, or a sub-pixel, of the light-emissive display, and wherein the first electrode layer and/or the second electrode layer comprises a plurality of electrodes, each electrode comprising at least two sub-electrodes associated with each discrete light-emissive region.

Abstract: Display driver circuitry for electro-optic displays, in particular active matrix displays using organic light emitting diodes. The circuitry includes a driver to drive an electro-optic display element in accordance with a drive voltage, a photosensitive device optically coupled to the electro-optic display element to pass a current dependent upon illumination reaching photosensitive device, a control circuit having a control line coupled to the driver to control the brightness of the electro-optic display element and having a current sense input coupled to the photosensitive device, a current set line for coupling to a reference current generator, and a display element select line to, when active, cause the control circuit to drive the electro-optic display element in accordance with the current set by the reference current generator. The circuit provides improved control of an electro-display element such as an organic LED pixel.