Abstract: An electronic device comprising: an electronic substrate comprising circuit elements; a double bank well-defining structure disposed over the electronic substrate, the double bank well-defining structure comprising a first layer of insulating material and a second layer of insulating material thereover, the second layer of insulating material having a lower wettability than the first layer of insulating material; and organic semiconductive material disposed in wells defined by the double bank well-defining structure.
Abstract: An organic electroluminescent device cfomprising: a transparent substrate; a first electrode disposed over the substrate for injecting charge of a first polarity; a second electrode disposed over the first electrode for injecting charge of a second polarity opposite to said first polarity; an organic light-emitting layer disposed between the first and the second electrode, wherein the second electrode is reflective, the first electrode is transparent or semi-transparent, and one or more intermediate layers of dielectric material with a refractive index greater than 1.
Type:
Application
Filed:
August 4, 2005
Publication date:
February 24, 2011
Applicant:
CAMBRIDGE DISPLAY TECHNOLOGY LIMITED
Inventors:
Euan C. Smith, Faisal Qureshi, Jan Jongman
Abstract: A pixel driver circuit for active matrix driving of an organic light emitting diode (OLED) comprises a drive transistor having a current path connected to a first voltage supply line at one end and to an OLED at the other end and a gate terminal connected to a storage element connected between gate and source of the drive transistor to memorize a drive signal for the drive transistor under the control of a first switch transistor having a gate connection to a first selection line and a current path connected between gate and drain of the drive transistor, and a second switch transistor having a gate connection to a second selection line, wherein the second switch transistor has a current path connected to the data line at one end and a node at the other end located between the drive transistor and the OLED.
Abstract: A composition suitable for fabricating an electronic device such as an OLED using an ink-jet printing technique comprises a conducting or semi-conducting organic material and a solvent, the solvent having a boiling point of greater than 250° C. and a viscosity of less than 5 cPs. The composition preferably has a viscosity in the range between 0.1 and 20 cPs, and the solvent preferably has the formula: where R represents a C6 to C11 alkyl. The high boiling point of the solvent allows the “ink” to remain wet for a longer time after printing. This provides better process control during drying, resulting in more uniform films and greater control over the film profile. The low viscosity of the solvent enables jetting of the composition at high frequencies.
Abstract: A method of forming an organic thin film transistor comprising source and drain electrodes with a channel region therebetween, a gate electrode, a dielectric layer disposed between the source and drain electrodes and the gate electrode, and an organic semiconductor disposed in at least the channel region between the source and drain electrodes, said method comprising: seeding a surface in the channel region with crystallization sites prior to deposition of the organic semiconductor; and depositing the organic semiconductor onto the seeded surface whereby the organic semiconductor crystallizes at the crystallization sites forming crystalline domains in the channel region.
Abstract: A method of manufacturing an organic thin film transistor, comprising: providing a substrate comprising source and drain electrodes defining a channel region; subjecting at least the channel region to a cleaning treatment step; and depositing organic semiconductive material from solution into the channel region by inkjet printing.
Abstract: A pulsed-driven device, such as a display, comprises an organic light-emitting composition comprising a host material and a blended or bound phosphorescent emitter. The phosphorescent emitter is present in the host material at a concentration of greater than 10 wt. %, and the host material has a higher triplet energy level than the phosphorescent emitter. The concentration at which the phosphorescent emitter is at peak efficiency in the host material is greater than 10 wt. %, and the composition does not include a fluorescent emitter, so that emission from the composition in use is substantially all phosphorescence.
Abstract: This disclosure generally relates to improved structures for organic light emitting diodes (OLEDs), and more particularly to so-called top emitting OLEDs.
Abstract: This invention relates to systems, methods and apparatus for driving organic light emitting diodes (OLED) displays, in particular those using multi-line addressing (MLA) techniques. Embodiments of the invention are particularly suitable for use with so-called passive matrix OLED displays. A current drive system for an electroluminescent display, the system comprising: a plurality of current mirrors having a plurality of outputs for driving a plurality of drive electrodes of said display, each said current mirror having a reference signal input; and an automatic selector coupled to said current mirror outputs to automatically select a said output for providing reference signal inputs to said current mirrors.
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: An optical device comprising an anode, a cathode, an organic semiconducting material between the anode and the cathode, and an electron transport layer between the cathode and the organic semiconducting material wherein the organic semiconducting material comprises sulfur and the electron transport layer containing barium.
Abstract: An organic light-emitting device comprising an anode; a hole transport layer; a light-emitting layer; and a cathode, characterised in that the hole transport layer comprises a polymer having a repeat unit comprising a 9,9 biphenyl fluorene unit wherein the 9-phenyl rings are independently and optionally substituted and the fluorene unit is optionally fused.
Abstract: A method of manufacturing an organic thin film transistor, comprising: providing a substrate comprising source and drain electrodes defining a channel region; forming a patterned layer of insulting material defining a well surrounding the channel region; depositing a protective layer in the well; subjecting exposed portions of the patterned layer of insulating material to a de-wetting treatment to lower the wettability of the exposed portions; removing the protective layer; and depositing organic semiconductive material from solution into the well.
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.
Type:
Application
Filed:
September 26, 2008
Publication date:
October 14, 2010
Applicant:
CAMBRIDGE DISPLAY TECHNOLOGY LTD.
Inventors:
Euan C. Smith, Richard Alan Page, Stefan Wurster, Barry Thompson
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.
Type:
Application
Filed:
September 26, 2008
Publication date:
October 14, 2010
Applicant:
CAMBRIDGE DISPLAY TECHNOLOGY LIMITED
Inventors:
Euan C. Smith, Richard Alan Page, Stefan Wurster, Barry Thompson
Abstract: This invention relates to pixel driver circuits for active matrix optoelectronic devices, in particular OLED (organic light emitting diodes) displays. We describe an active matrix optoelectronic device having a plurality of active matrix pixels each said pixel including a pixel circuit comprising a thin film transistor (TFT) for driving the pixel and a pixel capacitor for storing a pixel value, wherein said TFT comprises a TFT with a floating gate.
Type:
Application
Filed:
October 29, 2008
Publication date:
October 7, 2010
Applicant:
CAMBRIDGE DISPLAY TECHNOLOGY LTD.
Inventors:
Aleksandra Rankov, Euan Christopher Smith
Abstract: A formulation for depositing a material on a substrate, the formulation comprising the material to be deposited on the substrate dissolved in a solvent system comprising a first solvent component having a relatively high boiling point and which exhibits a relatively low solubility with respect to the material to be deposited, and a second solvent component having a relatively low boiling point and which exhibits a relatively high solubility with respect to the material to be deposited.
Type:
Grant
Filed:
October 9, 2008
Date of Patent:
October 5, 2010
Assignee:
Cambridge Display Technology Limited
Inventors:
Christopher J. Bright, Julian Carter, Martin Cacheiro, Peter Lyon
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.
Type:
Application
Filed:
September 26, 2008
Publication date:
September 30, 2010
Applicant:
CAMBRIDGE DISPLAY TECHNOLOGY LIMITED
Inventors:
Euan C. Smith, David S. Warren, Richard Alan Page, Stefan Wurster, Barry Thompson
Abstract: An organic electroluminescence element having a cathode as a top electrode, and excelling in luminance efficiency, drive voltage, and operational life is provided. The organic electroluminescence element includes an anode over a substrate and a luminescent layer over the anode. The luminescent layer comprises an organic material. An electron injection layer is over the luminescent layer for injecting electrons into the luminescent layer. The electron injection layer is a metal including at least one of an alkaline metal and an alkaline earth metal. A fullerene layer is over the electron injection layer and includes fullerenes and at least one of an alkaline metal and an alkaline earth metal. The at least one of the alkaline metal and the alkaline earth metal included in the fullerene layer has a lower work function than a lowest unoccupied molecular orbit energy level of the fullerenes. A cathode is over the fullerene layer.