Patents by Inventor Richard H. Friend

Richard H. Friend has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8530269
    Abstract: A method of forming a polymer device including the steps (i) of depositing on a substrate a solution containing a polymer or oligomer and a crosslinking moiety, to form a layer, and, (ii) curing the layer formed in step (i) under conditions to form an insoluble crosslinked polymer, wherein the crosslinking moiety is present in step (i) in an amount in the range of from 0.05 mol % to 5 mol % based on the total number of moles or repeat units of the polymer or oligomer and the crosslinking moiety in the solution.
    Type: Grant
    Filed: May 12, 2004
    Date of Patent: September 10, 2013
    Assignee: Cambridge Enterprise Ltd
    Inventors: Lay-Lay Chua, Peter Kian-Hoon Ho, Richard H. Friend
  • Publication number: 20130069043
    Abstract: An electro optic device comprising a first electrode and a second electrode and an emissive layer located between the first and second electrodes, the emissive layer comprising a polymeric semiconductor, or semiconducting and luminescent material having a thickness of 200 nm to 3000 nm.
    Type: Application
    Filed: January 12, 2011
    Publication date: March 21, 2013
    Applicant: CAMBRIDGE ENTERPRISE LIMITED
    Inventors: Richard H. Friend, Henry Snaith, Dinesh Kabra, Myoung Hoon Song, Li Ping Lu
  • Publication number: 20110140091
    Abstract: A light emissive or photovoltaic device comprising: a cathode structure for injecting electrons, the cathode structure having one or more constituent regions; an anode structure for injecting holes, the anode structure having one or more constituent regions; and an organic light emissive component located between the anode structure and the cathode structure; the refractive indices and the thicknesses of the or each constituent region of the cathode and anode structures and of the light emissive component being such that the emission or absorption spectrum of the device is substantially angularly dependent.
    Type: Application
    Filed: June 18, 2009
    Publication date: June 16, 2011
    Applicant: CAMBRIDGE ENTERPRISE LIMITED
    Inventors: Richard H. Friend, Dinesh Kabra, Bernard Wenger, Henry Snaith, Myoung Hoon Song
  • Patent number: 6872970
    Abstract: A method of preparing an efficient photoresponsive device includes the steps of providing a first electrode on a substrate, providing a layer of an organic material including a blend of at least two semiconductive polymers having different electrode affinities and/or different ionization potentials over the first electrode, providing a second electrode over the layer of organic material, at least one of the electrodes being a transparent or semi-transparent, to form a photoresponsive device, and thermally annealing the photoresponsive device.
    Type: Grant
    Filed: December 18, 2003
    Date of Patent: March 29, 2005
    Assignee: Cambridge Display Technology Limited
    Inventors: Jonathan J. Halls, Richard H. Friend
  • Publication number: 20040201583
    Abstract: A display control device for a light-emissive display comprising: input means for receiving display data defining a visual display pattern, processing means for processing the display data to generate control data for controlling the pixels of the display and having a first, normal mode of operation in which it controls the pixels to display the pattern as defined by the display data, and a second, power-saving mode of operation in which it controls a set of pixels of the display to operate with reduced power consumption whilst maintaining display of the pattern, and output means for connection to the pixels to transmit the control data to the pixels.
    Type: Application
    Filed: April 29, 2004
    Publication date: October 14, 2004
    Applicant: Cambridge Display Technology Limited
    Inventors: Jeremy Burroughes, Richard H. Friend, Karl Pichler
  • Publication number: 20040132226
    Abstract: A method of preparing an efficient photoresponsive device includes the steps of providing a first electrode on a substrate, providing a layer of an organic material including a blend of at least two semiconductive polymers having different electrode affinities and/or different ionization potentials over the first electrode, providing a second electrode over the layer of organic material, at least one of the electrodes being a transparent or semi-transparent, to form a photoresponsive device, and thermally annealing the photoresponsive device.
    Type: Application
    Filed: December 18, 2003
    Publication date: July 8, 2004
    Applicant: Cambridge Display Technology Limited
    Inventors: Jonathan J. Halls, Richard H. Friend
  • Patent number: 6670213
    Abstract: A method of preparing an efficient photoresponsive device includes the steps of providing a first electrode on a substrate, providing a layer of an organic material including a blend of at least two semiconductive polymers having different electrode affinities and/or different ionization potentials over the first electrode, providing a second electrode over the layer of organic material, at least one of the electrodes being a transparent or semi-transparent, to form a photoresponsive device, and thermally annealing the photoresponsive device.
    Type: Grant
    Filed: October 10, 2001
    Date of Patent: December 30, 2003
    Assignee: Cambridge Display Technology Limited
    Inventors: Jonathan J. Halls, Richard H. Friend
  • Patent number: 6608323
    Abstract: The new fluorocarbon-functionalized polythiophenes, in particular, &agr;,&ohgr;-diperfluorohexylsexithiophene DFH-6T (1) can be straightforwardly prepared in high yield and purified by gradient sublimation. Introduction of perfluorocarbon chains on the thiophene core affords enhanced thermal stability and volatility, and increased electron affinity versus the fluorine-free analog 2. Evaporated films of 1, for example, behave as n-type semiconductors, and can be used to fabricate thin film transistors with FET mobilities on the order of ˜0.01 cm2/Vs—some of the highest reported to date for n-type organic semiconductors.
    Type: Grant
    Filed: July 24, 2001
    Date of Patent: August 19, 2003
    Assignees: Northwestern University, Cambridge Univ. Technical Services, Ltd.
    Inventors: Tobin J. Marks, Antonio Facchetti, Henning Sirringhaus, Richard H. Friend
  • Publication number: 20030066950
    Abstract: A method of preparing an efficient photoresponsive device includes the steps of providing a first electrode on a substrate, providing a layer of an organic material including a blend of at least two semiconductive polymers having different electrode affinities and/or different ionization potentials over the first electrode, providing a second electrode over the layer of organic material, at least one of the electrodes being a transparent or semi-transparent, to form a photoresponsive device, and thermally annealing the photoresponsive device.
    Type: Application
    Filed: October 10, 2001
    Publication date: April 10, 2003
    Inventors: Jonathan J. Halls, Richard H. Friend
  • Patent number: 6498049
    Abstract: A method for forming a display device, comprising: depositing a thin-film transistor switch circuit on a substrate; depositing by ink-jet printing an electrode layer of light transmissive conductive organic material in electrical contact with the output of the thin-film transistor circuit; and depositing an active region of the device over the electrode layer.
    Type: Grant
    Filed: August 17, 2000
    Date of Patent: December 24, 2002
    Assignees: Cambridge Display Technology, Seiko Epson Corporation
    Inventors: Richard H. Friend, Carl R. Towns, Julian C. Carter, Stephen K. Heeks, Hermann F. Wittman, Karl Pichler, Ichio Yudasaka
  • Patent number: 6429601
    Abstract: An organic light-emitting device having an organic light-emitting region comprising a plurality of organic light-emitting pixels; switch means each associated with a respective pixel for switching power to that pixel; and drive means for driving each switch means to cycle between a first, low power mode and a second, high power mode, at a frequency sufficient to cause light emission from the associated pixel to appeal substantially continuous, the duration of the highpower mode relative to the low power mode being variable so as to vary the average brightness of the pixel.
    Type: Grant
    Filed: August 17, 2000
    Date of Patent: August 6, 2002
    Assignee: Cambridge Display Technology Ltd.
    Inventors: Richard H. Friend, Jeremy H. Burroughes, Mutsumi Kimura, Stephen K. Heeks
  • Publication number: 20020053666
    Abstract: The new fluorocarbon-functionalized polythiophenes, in particular, &agr;,&ohgr;-diperfluorohexylsexithiophene DFH-6T (1) can be straightforwardly prepared in high yield and purified by gradient sublimation. Introduction of perfluorocarbon chains on the thiophene core affords enhanced thermal stability and volatility, and increased electron affinity versus the fluorine-free analog 2. Evaporated films of 1, for example, behave as n-type semiconductors, and can be used to fabricate thin film transistors with FET mobilities on the order of ˜0.01 cm2/Vs—some of the highest reported to date for n-type organic semiconductors.
    Type: Application
    Filed: July 24, 2001
    Publication date: May 9, 2002
    Applicant: Northwestern University
    Inventors: Tobin J. Marks, Antonio Facchetti, Henning Sirringhaus, Richard H. Friend
  • Patent number: 5670791
    Abstract: First and second electrodes (3 and 4) are provided on respective ones (2' and 2") of the first and second major surfaces of a photoresponsive zone (2). The photoresponsive zone (2) is in the form of a polymer blend having regions (2a) of a first semiconductive polymer and regions (2b) of a second semiconductive polymer phase-separated from the first semiconductive polymer. The second semiconductive polymer has an electron affinity greater than that of the first semiconductive polymer so that, in use of the device (1), a photocurrent between the first and second electrodes (3 and 4) resulting from light incident on the photoresponsive layer comprises electrons travelling predominantly through the second semiconductive polymer and holes travelling predominantly through the first semiconductive polymer.
    Type: Grant
    Filed: November 22, 1995
    Date of Patent: September 23, 1997
    Assignee: U.S. Philips Corporation
    Inventors: Jonathan J. M. Halls, Richard H. Friend
  • Patent number: 5523555
    Abstract: A photodetector device includes a semiconductive conjugated polymer, such as PPV, arranged between first and second electrode layers having different work functions, a bias circuitry connected to apply a bias voltage between the first and second electrode layers, and a sensing circuitry connected to detect a photocurrent flowing between the first and second electrode layers across the polymer layer as a result of radiation incident on the polymer layer while the bias voltage is applied. The bias voltage is selected in relation to the thickness of the polymer layer.
    Type: Grant
    Filed: September 14, 1994
    Date of Patent: June 4, 1996
    Assignee: Cambridge Display Technology
    Inventors: Richard H. Friend, Andrew B. Holmes, Donal D. C. Bradley, Robert N. Marks
  • Patent number: 5514878
    Abstract: This invention provides semiconductive conjugated polymers incorporating electron-withdrawing groups for use in electroluminescent devices, methods for their manufacture, and electroluminescent devices incorporating the polymers. The electron-withdrawing group is conjugatively linked to the polymer chain and is selected so that the polymer exhibits electroluminesence upon application of an electric field to a layer thereof.
    Type: Grant
    Filed: March 18, 1994
    Date of Patent: May 7, 1996
    Inventors: Andrew B. Holmes, Richard H. Friend, Stephen C. Moratti, Derek R. Baigent, Donald C. Bradley, Raoul Cervini, Neil C. Greenham, Peter J. Hamer
  • Patent number: 5512654
    Abstract: A semiconductive conjugated copolymer comprises at least two chemically different monomer units which, when existing in their individual homopolymer forms, have different semiconductor bandgaps. The proportion of said at least two chemically different monomer units in the copolymer is selected to control the semiconductor bandgap of the copolymer so as to control the optical properties of the copolymer. The copolymer is formed in a manner enabling it to be laid down as a film without substantially affecting the luminescent characteristics of the copolymer and is stable at operational temperature.The semiconductor bandgap may be spatially modulated so as to increase the quantum efficiency of the copolymer when excited to luminesce, to select the wavelength of radiation emitted during luminescence or to select the refractive index of the copolymer.
    Type: Grant
    Filed: May 19, 1994
    Date of Patent: April 30, 1996
    Assignee: Cambridge Display Technology Limited
    Inventors: Andrew Holmes, Donal D. Bradley, Richard H. Friend, Arno Kraft, Paul Burn, Adam Brown
  • Patent number: 5425125
    Abstract: A method is provided for forming in a semiconductive conjugated polymer at least first and second legions having different optical properties. The method comprises: forming a layer of a precursor polymer and permitting the first region to come into contact with a reactant, such as an acid, and heat while permitting the second region to come into contact with a lower concentration of the reactant. The reactant affects the conversion conditions of the precursor polymer in such a way as to control the optical properties of at least the first region so that the optical properties of the first region are different from those of the second region. The precursor polymer may comprise a poly(arylene-1, 2-ethanediyl) polymer, at least some of the ethane groups of which include a modifier group whose susceptibility to elimination is increased in the presence of the reactant.
    Type: Grant
    Filed: February 18, 1994
    Date of Patent: June 13, 1995
    Assignee: Cambridge Display Technology Limited
    Inventors: Andrew B. Holmes, Donal D. Bradley, Richard H. Friend, Paul L. Burn, Arno Kraft, Adam R. Brown
  • Patent number: 5401827
    Abstract: A semiconductive conjugated copolymer comprises at least two chemically different monomer units which, when existing in their individual homopolymer forms, have different semiconductor bandgaps. The proportion of said at least two chemically different monomer units in the copolymer is selected to control the semiconductor bandgap of the copolymer so as to control the optical properties of the copolymer. The copolymer is formed in a manner enabling it to be laid down as a film without substantially affecting the luminescent characteristics of the copolymer and is stable at operational temperature.The semiconductor bandgap may be spatially modulated so as to increase the quantum efficiency of the copolymer when excited to luminesce, to select the wavelength of radiation omitted during luminescence or to select the refractive index of the copolymer.
    Type: Grant
    Filed: August 22, 1991
    Date of Patent: March 28, 1995
    Assignee: Cambridge Display Technology Limited
    Inventors: Andrew Holmes, Donal D. Bradley, Richard H. Friend, Arno Kraft, Paul Burn, Adam Brown
  • Patent number: 5399502
    Abstract: An electroluminescent device includes a semiconductor layer (4) in the form of a thin dense polymer film comprising at least one conjugated polymer, a first contact layer (5) in contact with a first surface of the semiconductor layer, and a second contact layer (3) in contact with a second surface of the semiconductor layer. The polymer film (4) of the semiconductor layer has a sufficiently low concentration of extrinsic charge carriers that on applying an electric field between the first and second contact layers across the semiconductor layer so as to render the second contact layer positive relative to the first contact layer charge carriers are injected into the semiconductor layer and radiation is emitted from the semiconductor layer.
    Type: Grant
    Filed: May 5, 1993
    Date of Patent: March 21, 1995
    Assignee: Cambridge Display Technology Limited
    Inventors: Richard H. Friend, Jeremy H. Burroughes, Donal D. Bradley
  • Patent number: 5328809
    Abstract: A method is provided for forming in a semiconductive conjugated polymer at least first and second regions having different optical properties. The method comprises: forming a layer of a precursor polymer and permitting the first region to come into contact with a reactant, such as an acid, and heat while permitting the second region to come into contact with a lower concentration of the reactant. The reactant affects the conversion conditions of the precursor polymer in such a way as to control the optical properties of at least the first region so that the optical properties of the first region are different from those of the second region.The precursor polymer may comprise a poly(arylene-1,2-ethanediyl) polymer, at least some of the ethane groups of which include a modifier group whose susceptibility to elimination is increased in the presence of the reactant.
    Type: Grant
    Filed: August 22, 1991
    Date of Patent: July 12, 1994
    Assignee: Cambridge Display Technology Limited
    Inventors: Andrew Holmes, Donal D. Bradley, Richard H. Friend, Arno Kraft, Paul Burn, Adam Brown