Patents Assigned to Cambridge Display Technology Limited
  • Publication number: 20120182265
    Abstract: An apparatus such as a touch screen display includes correlated emitter-detector pairs for determining the amount of electromagnetic radiation received at a detector from its paired emitter. The apparatus comprises an array of emitters operable to emit electromagnetic radiation, an array of detectors for detecting the electromagnetic radiation, and drive control circuitry configured to control the array of emitters so that they emit pulses of electromagnetic radiation. The amplitude of the pulses is modulated using mutually orthogonal binary vectors such as a Paley construction of the Hadamard matrix. Each emitter has a different vector associated with it. Detection circuitry is provided to detect the electromagnetic radiation reaching each particular detector in the array of detectors using the mutually orthogonal binary vector associated with the correlated emitter to produce a correlation between particular emitter-detector pairs. The arrangement can discriminate between near field and touching objects.
    Type: Application
    Filed: August 31, 2010
    Publication date: July 19, 2012
    Applicant: Cambridge Display Technology Limited
    Inventors: Euan Smith, Aleksandra Rankov
  • Patent number: 8216874
    Abstract: An optical device comprising an anode, a cathode comprising barium, strontium or calcium, and a layer of organic semiconducting material between the anode and the cathode wherein a layer of hole transporting and electron blocking material is located between the anode and the layer of organic semiconducting material.
    Type: Grant
    Filed: April 30, 2009
    Date of Patent: July 10, 2012
    Assignee: Cambridge Display Technology Limited
    Inventors: Brian Tierney, Ilaria Grizzi, Clare Louise Foden, Nalinkumar L. Patel, Mark Leadbeater
  • Patent number: 8212270
    Abstract: A method of manufacturing a transparent encapsulating sheet for a light-emissive device, the method comprising the steps: forming a plurality of cavities in one side of a transparent sheet of material for receiving light-emissive structures therein, said forming step producing a frosted surface comprising micro cracks in the cavities; coating said frosted surface with a low viscosity material whereby the micro cracks in the frosted surface are filled with the low viscosity material in order to form the transparent encapsulating sheet.
    Type: Grant
    Filed: December 1, 2006
    Date of Patent: July 3, 2012
    Assignee: Cambridge Display Technology Limited
    Inventors: Russell Lees, Angela Lees, legal representative
  • Patent number: 8206562
    Abstract: The invention relates to a method and apparatus for the application of material to form a layer of an organic electroluminescent device. The material is sputter deposited typically from at least one target of material held in respect to a magnetron in a coating chamber. The magnetrons used can be unbalanced magnetrons and/or are provided with other magnetrons and/or magnet arrays in a closed field configuration. The material is found to be deposited in a manner which prevents or minimises damage to the device and hence reduces or removes the need for a barrier layer to be applied.
    Type: Grant
    Filed: February 16, 2006
    Date of Patent: June 26, 2012
    Assignees: Cambridge Display Technology Limited, System Control Technologies Limited
    Inventors: John Michael Walls, Desmond Gibson, William Young, Nalinkumar Patel, Nicoletta Anathassopoulou
  • Patent number: 8187669
    Abstract: Disclosed are compositions, useful in ink jet printing methods, that prevent clogging during dispensing, achieve stable dispensing, prevent precipitation of content matter during dispensing, and prevent phase separation during film formation. Also disclosed are uniform, homogenous, functional films formed using the compositions and manufacturing methods therefor, as well as organic EL devices and other such display devices and manufacturing methods therefor. The compositions contain a functional material and a solvent comprising at least one benzene derivative having one or more substituents, whereby the substituents have at least three carbon atoms in total.
    Type: Grant
    Filed: March 10, 2009
    Date of Patent: May 29, 2012
    Assignees: Seiko Epson Corporation, Cambridge Display Technology Limited
    Inventors: Sadao Kanbe, Shunichi Seki
  • Patent number: 8188949
    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 defined 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.
    Type: Grant
    Filed: December 12, 2008
    Date of Patent: May 29, 2012
    Assignee: Cambridge Display Technology Limited
    Inventors: Euan C. Smith, Paul R. Routley, William Goodchild
  • Publication number: 20120126688
    Abstract: An organic electroluminescent device comprising: a 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; and an encapsulant disposed over the second electrode, wherein the second electrode and the encapsulant are transparent to light emitted by the light emitting layer, wherein a cavity is provided between the encapsulant and the second electrode, and wherein an anti-reflective coating is provided on at least one side of the encapsulant for reducing reflection of light emitted by the light emitting layer so as to improve out-coupling of light from the device, said anti-reflective coating being transparent to light emitted by the light emitting layer.
    Type: Application
    Filed: May 24, 2006
    Publication date: May 24, 2012
    Applicant: Cambridge Display Technology Limited
    Inventors: Martin Richardson, Nalinkumar Patel, Russell Lees, Angela Lees, Matthew Roberts
  • Patent number: 8173996
    Abstract: A semiconductive hole transport material containing polar substituent groups, the polar substituent groups substantially not affecting the electronic properties of the hole transport material and the hole transport material being soluble in a polar solvent.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: May 8, 2012
    Assignees: Cambridge Display Technology Limited, CDT Oxford Limited
    Inventors: Carl R. Towns, Caroline Towns, legal representative, Mary J. McKiernan, Annette Steudel
  • Publication number: 20120095184
    Abstract: A monomer having the general formula: in which R1 is any substitution; R2 is any substitution; R1 and R2 may be linked to form a saturated or unsaturated ring; L represents a reactive leaving group; X and Y each independently represent CR2, O, BR, NR, SiR2, S, S?O, SO2, PR or P?O(R) wherein R in each occurrence is independently selected from H or a substituent; Z represents a single bond or a divalent atom or group, wherein X—Z—Y forms an unconjugated ring or chain, with the proviso that at least one of R1 and R2 is an aryl or heteroaryl group if Z is a single bond.
    Type: Application
    Filed: April 15, 2010
    Publication date: April 19, 2012
    Applicants: Sumitomo Chemical Company Limited, Cambridge Display Technology Limited
    Inventors: Mary McKiernan, Johathan Pillow
  • Publication number: 20120085994
    Abstract: An electroluminescent polymer comprising light-emissive repeat units and a non-emissive polycyclic aromatic hydrocarbon unit with greater than 12 aromatic sp2 hybridized carbon atoms, wherein the non-emissive polycyclic aromatic hydrocarbon unit comprises a structural unit having formula I:
    Type: Application
    Filed: April 15, 2010
    Publication date: April 12, 2012
    Applicant: CAMBRIDGE DISPLAY TECHNOLOGY LIMITED
    Inventors: Jonathan Pillow, Ilaria Grizzi, Martin Humphries, Ian Warburton
  • Publication number: 20120068140
    Abstract: A switchable electronic device comprises a hole blocking layer and a layer comprising a conductive material between first and second electrodes, wherein the conductivity of the device may be irreversibly switched upon application of a current having a current density of less than or equal to 100 A cm?2 to a conductivity at least 100 times lower than the conductivity of the device before switching. The conductive material is a doped organic material such as doped optionally substituted poly(ethylene dioxythiophene).
    Type: Application
    Filed: May 4, 2010
    Publication date: March 22, 2012
    Applicant: CAMBRIDGE DISPLAY TECHNOLOGY LIMITED
    Inventors: Neil Greenham, Jianpu Wang
  • Publication number: 20120065338
    Abstract: An organic light emitting device having a phase-separated light-emissive layer comprising: a charge transport phase comprising a charge transport material; and an emitting phase, the emitting phase comprising a plurality of discrete emissive domains dispersed in the charge transport phase, each emitting domain comprising a host material and one or more metal complexes for emitting light by phosphorescence; wherein the charge transport material has a T1 energy level lower than the T1 energy level of the metal complexes and the host material has a T1 energy level higher than the T1 energy level of the metal complexes.
    Type: Application
    Filed: November 15, 2011
    Publication date: March 15, 2012
    Applicants: CAMBRIDGE DISPLAY TECHNOLOGY LIMITED, CDT OXFORD LIMITED
    Inventors: Carl Towns, Andrew Bruce Holmes, Stephen O'Connor
  • Publication number: 20120053315
    Abstract: A monomer of formula (III): wherein X is a polymerisable group Ar, Ar1 and Ar2 each independently represent an optionally substituted aryl or heteroaryl group; R1 represents H or a substituent; and Z represents a direct bond or a divalent linking atom or group, wherein Ar1 and Ar2 are linked by a single bond or a divalent linking group selected from CR1R2, SiR1R2, PR1, NR1, O and S wherein R1 and R2 are independently selected from hydrogen; optionally substituted alkyl wherein one or more non-adjacent C atoms may be replaced with O, S, N, C?O and —COO—; alkoxy, aryl, arylalkyl, heteroaryl and heteroarylalkyl. Ar1 and Ar2 are preferably linked by an oxygen atom, and Ar1 and/or Ar2 may be fused to their respective adjacent Ar groups. Ar1 and its adjacent Ar group and/or Ar2 and its adjacent Ar group are optionally fused to form a fluorene unit.
    Type: Application
    Filed: April 15, 2010
    Publication date: March 1, 2012
    Applicants: Sumitomo Chemical Company Limited, Cambridge Display Technology Limited
    Inventors: Mary McKiernan, Thomas Pounds
  • Patent number: 8124248
    Abstract: A polymer blend comprising a first, light-emissive polymer comprising substituted or non-substituted units according to formulae (I) and (II) and a second, hole transport polymer comprising substituted or non-substituted fluorene units according to formula (I) and substituted or non-substituted triarylamine units, wherein the molecular weights of the first and second polymers and the blending ratio of the first and second polymers are selected such that, in use in a light-emissive device, the luminance of the emitted light at a bias of 5V is no less than 20,000 cd/m2. wherein R? is independently in each occurrence H, C1-C20 hydrocarbyl or C1-C20 hydrocarbyl containing one or more S, N, O, P or Si atoms, C4-C16 hydrocarbyl carbonyloxy, C4-C16 aryl(trialkylsiloxy) or both R? may form together with the 9-carbon on the fluorene ring a C5-C20 cycloaliphatic structure containing one or more heteroatoms of S, N or O.
    Type: Grant
    Filed: November 9, 2006
    Date of Patent: February 28, 2012
    Assignee: Cambridge Display Technology Limited
    Inventor: Salvatore Cina
  • Publication number: 20120046440
    Abstract: A method for forming a polymer comprising the polymerization of a plurality of monomers, wherein at least one of the plurality of monomers is one or both of: a charge transporting unit and a hydrocarbon monomer in which at least one carbon atom has been substituted by an atom or group with a greater quantity of unshared valence electrons than the carbon atom it has been substituted for, and wherein at least one of the plurality of monomers comprises an end-capping compound at one end of said monomer, the end-capping compound preventing polymerization at the end, wherein the end-capping compound is not charge transporting and comprises at least two rings. The end capping compound preferably consists of or includes a structural unit having the formula: (Ar)n—X, wherein Ar in each occurrence independently represents an aryl or heteroaryl group; X represents a leaving group comprising a boron derivative group or halogen; and n is 2 or more.
    Type: Application
    Filed: April 15, 2010
    Publication date: February 23, 2012
    Applicants: SUMITOMO CHEMICAL COMPANY LIMITED, CAMBRIDGE DISPLAY TECHNOLOGY LIMITED
    Inventors: Mary McKiernan, Thomas Pounds
  • Publication number: 20120037915
    Abstract: A method of forming an organic thin film transistor the method comprising: seeding a surface outside a channel region with one or more crystallization sites prior to deposition of the organic semiconductor; depositing a solution of the organic semiconductor onto the seeded surface and over the channel region whereby the organic semiconductor begins forming a crystal domain at the or each of the crystallization sites, the or each crystal domain growing from its crystallization site across the channel region in a direction determined by an advancing surface evaporation front; and applying energy to control the direction and rate of movement of the surface evaporation front thereby controlling the direction and rate of growth of the or each crystal domain across the channel region from the one or more crystallization sites outside the channel region.
    Type: Application
    Filed: April 13, 2010
    Publication date: February 16, 2012
    Applicant: CAMBRIDGE DISPLAY TECHNOLOGY LIMITED
    Inventor: Thomas Kugler
  • Publication number: 20120037907
    Abstract: A method of manufacturing an organic thin film transistor, the method comprising: depositing a source and drain electrode over a substrate using a solution processing technique; forming a workfunction modifying layer over the source and drain electrodes using a solution processing technique; and depositing an organic semi-conductive material in a channel region between the source and drain electrode using a solution processing technique.
    Type: Application
    Filed: January 27, 2010
    Publication date: February 16, 2012
    Applicant: Cambridge Display Technology Limited
    Inventors: Gregory Whiting, Jeremy Burroughes, Julian Carter, Jonathan Halls, Karl Weber
  • Patent number: 8115216
    Abstract: An optoelectronic display comprising a plurality of pixels, each pixel comprising a plurality of sub-pixels, wherein the optoelectronic display comprises a colour-forming layer which is patterned providing a plurality of discrete colour-forming regions in a two-dimensional array, and wherein an addressing array is provided for addressing the discrete colour-forming regions, at least some of the discrete colour-forming regions having portions which are separately addressable by the addressing array, each portion defining a sub-pixel of the optoelectronic display.
    Type: Grant
    Filed: April 5, 2007
    Date of Patent: February 14, 2012
    Assignee: Cambridge Display Technology Limited
    Inventors: Euan Smith, Mark Bale
  • Patent number: 8115704
    Abstract: A method of driving an emissive display, the display comprising a plurality of pixels each addressable by a row electrode and a column electrode, the method comprising: driving a plurality of the column electrodes with a first set of column drive signals; and driving two or more of the row electrodes with a first set of forward bias row drive signals at the same time as the column electrode driving with the column drive signals; then driving the plurality of column electrodes with a second and subsequent sets of column drive signals; and driving the two or more row electrodes with a second and subsequent sets of forward bias row drive signals at the same time as the column electrode driving with the second column drive signals.
    Type: Grant
    Filed: September 29, 2005
    Date of Patent: February 14, 2012
    Assignee: Cambridge Display Technology Limited
    Inventors: Euan Christopher Smith, Paul Richard Routley, Jonathan James Michael Halls
  • Publication number: 20120007068
    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.
    Type: Application
    Filed: September 22, 2011
    Publication date: January 12, 2012
    Applicant: CAMBRIDGE DISPLAY TECHNOLOGY LIMITED
    Inventors: Euan C. Smith, Matthew Roberts, William Young, Clare Louise Foden