Photoconductive (e.g., Light Sensitive) Patents (Class 338/15)
  • Patent number: 4553928
    Abstract: An improved multiple flashlamp array is disclosed having a plurality of low voltage type lamps fired individually and in sequence by means of a plurality of static solid switching devices capable of reliable actuation by radiant energy generated during flashing of the lamps. Initially, these switching devices have a high electrical resistance ("off position") and after being actuated by the heat and light radiation, they undergo chemical conversion to an electrically conductive state ("on position"). The switch devices are prepared in a conventional manner from a particulate mixture of silver oxide with oxidized copper metal and which further contains a particular organic polymer binder mixture. The low voltage flashlamps being fired in this manner require that the converted switch devices exhibit an electrical resistance after conversion not to exceed about 0.3 ohms.
    Type: Grant
    Filed: February 25, 1983
    Date of Patent: November 19, 1985
    Assignee: General Electric Company
    Inventors: Steven C. Lorenzen, Vaughn C. Sterling
  • Patent number: 4523090
    Abstract: A light controlled fader for providing an analog voltage output of approximately linear proportion to the position of a slider-type control mechanism. The fader includes coacting first light emitting and receiving members and coacting second light emitting and receiving members. A control member is provided to allow the amount of light received by the first and second light receiving members to be varied in an inverse proportion to one another.
    Type: Grant
    Filed: June 20, 1983
    Date of Patent: June 11, 1985
    Inventor: Warren E. Wagner
  • Patent number: 4490709
    Abstract: A photoconducting device fabricated from Fe-doped, semi-insulating InP crystals exhibits an exponential decay transient with decay time inversely related to Fe concentration. Photoconductive gain as high as 5 is demonstrated in photoconducting devices with AuGe and AuSn contacts. Response times from 150 to 1000 picoseconds can be achieved.
    Type: Grant
    Filed: December 6, 1982
    Date of Patent: December 25, 1984
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Robert B. Hammond, Nicholas G. Paulter, Ronald S. Wagner
  • Patent number: 4487574
    Abstract: A multiple flashlamp array is disclosed having a plurality of lamps fired individually and in sequence by means of a plurality of static solid switching devices capable of reliable actuation by radiant energy generated during flashing of the lamps. Initially, these switching devices have a high electrical resistance ("off position") and after being actuated by the heat and light radiation, they undergo chemical conversion to an electrically conductive state ("on position"). The switch devices are prepared in a conventional manner from a particulate mixture of silver oxide with a metal exhibiting both thermal and electrical conductivity but which does not react exothermally with said silver oxide. A binder mixture is used which includes a conventional organic polymer binder which serves as a fuel during conversion of the silver oxide together with a second organic polymer binder which is more resistant to combustion.
    Type: Grant
    Filed: December 20, 1982
    Date of Patent: December 11, 1984
    Assignee: General Electric Company
    Inventors: Mary S. Jaffe, Vaughn C. Sterling
  • Patent number: 4482881
    Abstract: A semiconductor photoconductor having low impedance nonmetallic contacts is disclosed which has increased detectivity over prior art photoconductor structures. The improved photoconductor has metallic contacts that are separated by a contact length that is greater than the optical length of the detector. The contact regions of the semiconductor adjacent the detector region are thicker than the detector region. The process for fabricating the photoconductor includes thinning the detector region to an appropriate thickness while preserving the greater thickness of the contact regions.
    Type: Grant
    Filed: July 19, 1982
    Date of Patent: November 13, 1984
    Assignee: The Aerospace Corporation
    Inventors: Richard B. Schoolar, Alfred A. Fote
  • Patent number: 4462019
    Abstract: A photosensitive semiconductor resistor has a monocrystalline semiconductor body of one conductivity type which, on two oppositely located surfaces, is provided with an anode contact and with a cathode contact, and is constructed so that the cathode contact is a highly doped zone of the same conductivity type as the semiconductor body. The semiconductor body can be exposed to photon radiation at its surface supporting the cathode contact and the area of the anode contact is at least 1000 times larger than the area of the cathode contact. Such a photosensitive semiconductor resistor is easy to manufacture and has both a low inertia and a good sensitivity.
    Type: Grant
    Filed: February 1, 1982
    Date of Patent: July 24, 1984
    Assignee: U.S. Philips Corporation
    Inventors: Helmut Ewaldt, Gerhard Raabe, Heinz Sauermann, Rainer Burmeister
  • Patent number: 4431913
    Abstract: A one-dimensional scanner for use in an image reader in which the pitch of the electrode elements is reduced to increase the image density. An upper electrode array has a plurality of upper electrode elements arranged at a predetermined pitch and spacing in a one-dimensional scanning direction while a lower electrode array similarly has a plurality of lower electrode elements arranged at a predetermined pitch and spacing in the one-dimensional scanning direction in an opposed, spaced and staggered relation with respect to the upper electrode elements wherein each lower electrode element is positioned across two adjacent upper electrode elements thereby defining a picture element region therebetween. A layer of material such a photosensitive material, a layer having an electro-optical effect, or a layer of electric-radiant-energy-converting material is disposed between the upper and lower electrode arrays.
    Type: Grant
    Filed: August 24, 1981
    Date of Patent: February 14, 1984
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Souichi Sekimoto, Ryoki Kato
  • Patent number: 4423403
    Abstract: Cadmium-tin oxide films are prepared by d-c reactive sputtering of Cd-Sn alloys in Ar-O.sub.2 mixtures. The films obtained have low resistivity of the order of 10.sup.-3 -10.sup.-4 .OMEGA.-cm and high optical transparency depending upon deposition conditions.
    Type: Grant
    Filed: April 16, 1982
    Date of Patent: December 27, 1983
    Assignees: Hitachi, Ltd., Kiyoshi Miyake
    Inventors: Kiyoshi Miyake, Naoyuki Miyata
  • Patent number: 4405915
    Abstract: A photoelectric transducing element comprising (a) a substrate; (b) first electrode provided on said substrate; (c) first contact layer to form an ohmic contact with said first electrode with respect to electric charge in at least one polarity; (d) a photoconductive layer provided in contact with said first contact layer and composed of an amorphous material containing silicon atom as a matrix and hydrogen atom, or halogen atom, or both, at a ratio of 1 to 30 atomic % with respect to said silicon atom; (e) second contact layer provided in contact with said photoconductive layer; and (f) second electrode to form an ohmic contact with said second contact layer with respect to said charge.
    Type: Grant
    Filed: March 23, 1981
    Date of Patent: September 20, 1983
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyuki Komatsu, Masaki Fukaya, Shunichi Uzawa, Seishiro Yoshioka, Yoshiaki Shirato
  • Patent number: 4388606
    Abstract: A self-sequencing multilamp photoflash array responsive to a low voltage source includes radiation-responsive switches having a pair of electrical conductors spaced by a switch paste comprising a heat sensitive silver compound, a powdered metal in stoichiometric excess and an organic binder. The array has a flashlamp coupled to a pair of electrical conductors and a plurality of series connected flashlamps and radiant-responsive switches connected in parallel to the electrical conductors with each switch responsive to a previously energized flashlamp. Also, a process is provided for fabricating the switches and the array.
    Type: Grant
    Filed: April 13, 1981
    Date of Patent: June 14, 1983
    Assignee: GTE Products Corporation
    Inventors: John W. Shaffer, Boyd G. Brower
  • Patent number: 4334774
    Abstract: A means for aligning components of an optical system without the use of conventional optical equipment is disclosed. This means includes the use of a pair of electrodes in proximity with the light guiding portion of a pyroelectric system element. The absorption of light in the waveguide produces a current in the pyroelectric material that is monitored at the electrodes. Alignment of the system components is achieved by adjusting their relative position to increase the monitored signal.
    Type: Grant
    Filed: December 31, 1979
    Date of Patent: June 15, 1982
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Alastair M. Glass, Ivan P. Kaminow, Donald H. Olson
  • Patent number: 4307372
    Abstract: In a thin-film photosensor comprising a transparent electrode deposited on one surface of a thin layer of photoconductor, and a counter electrode deposited on the other surface thereof, a photosensor for use in a photosensor array of a facsimile transmitter or the like characterized in that part of the transparent electrode other than a window for incidence of a light signal is covered with an opaque thin film.
    Type: Grant
    Filed: December 31, 1979
    Date of Patent: December 22, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Makoto Matsui, Hideaki Yamamoto, Eiichi Maruyama
  • Patent number: 4299558
    Abstract: An improved solid state radiant energy switch device is described for operation with a plurality of flash lamps fired individually and in sequence and which is activated by radiant energy generated during flashing of the lamps to convert from a high electrical resistance ("off" condition) to a low electrical resistance or conductive state ("on" condition). Said switches are prepared from an improved material composition which undergoes chemical conversion comprising a carbon-containing silver salt admixed with a humidity-resistant organic polymer binder in ratios wherein said polymer binder does not exceed more than about three percent by weight in said admixture.
    Type: Grant
    Filed: May 21, 1979
    Date of Patent: November 10, 1981
    Assignee: General Electric Company
    Inventor: Juliana Pinkasovich
  • Patent number: 4297392
    Abstract: In the course of producing a thin film of amorphous silicon by high frequency sputtering elemental silicon under an atmosphere containing at least hydrogen gas, the temperature of the base plate onto which the amorphous silicon is deposited is maintained at a temperature of about 50.degree. C. to 150.degree. C. The thus obtained silicon film possesses not only photoconductivity sufficient for use as a photoconductor but also a large difference between photoconductivity and dard conductivity. In addition, a photoconductor of an amorphous silicon thin film can be produced at low cost without environmental pollution problems.
    Type: Grant
    Filed: November 2, 1979
    Date of Patent: October 27, 1981
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Akio Higashi, Kazuhiro Kawaziri, Yosuke Nakajima
  • Patent number: 4283702
    Abstract: A contactless conductance potentiometer is provided in which the total conductance between two electric terminals can be selectively divided, the two parts being equal to the total conductance. This can be accomplished by using a ring-shaped photoconductor on a substrate, the ring-shaped photoconductor being divided along a diametral line. One exterior electrode is located on the substrate in a position surrounding one portion of the ring-shaped photoconductor and being in contact with the marginal edge thereof. The remaining part of the ring-shaped photoconductor is in marginal contact with the second exterior electrode. A tapping electrode is mounted inside the ring-shaped photoconductor and is in marginal contact with the inner edge of the ring-shaped photoconductor.
    Type: Grant
    Filed: May 10, 1979
    Date of Patent: August 11, 1981
    Assignee: Heimann GmbH
    Inventors: Juergen Meyer, Norbert Schaaf
  • Patent number: 4276534
    Abstract: The present invention involves a structure of a contactless ohmic resistance potentiometer. A current path between two exterior electrodes is provided by a photoconductor, and a means is provided for causing an exposure of a portion of the length of the photoconductor between one exterior electrode and a tapping electrode. This permits a voltage division between two exterior electrodes. The usable surface of the photoconductor layer is delimited by an exterior electrode and a tapping electrode having a definite geometric course between the exterior electrodes. The distance ratio from the tapping electrode to the two exterior electrodes is varied by means of displacing the exposure of the photoconductor which causes the active partial surface of the photoconductor to be varied at will.
    Type: Grant
    Filed: May 10, 1979
    Date of Patent: June 30, 1981
    Assignee: Heimann GmbH
    Inventors: Juergen Meyer, Norbert Schaaf, Claus Kunze
  • Patent number: 4156558
    Abstract: A liquid crystal device comprising a liquid crystal layer intermediate a substrate coated by a surfactant and another substrate coated by a photoconductive and a surfactant thereover that is manufactured by taking cleaned electrically conductive transparent substrates and depositing a photoconductor such as cadmium sulfide to one with thereafter treating that one so as to coat it with a surfactant and at the same time coat the other substrate with a surfactant before joining the substrates with a liquid crystal therebetween whose molecules are oriented by the said surfactant.
    Type: Grant
    Filed: August 4, 1977
    Date of Patent: May 29, 1979
    Assignee: Grumman Aerospace Corporation
    Inventor: Alex Grumet
  • Patent number: 4103144
    Abstract: A low inductance, rapid response, heater for silicon photodetector and microcircuit applications is realized by depositing on a substrate surface a heater whose contact terminals and resistance element are configured to eliminate electrical noise due to the induced currents that commonly result from on-off switching action. The heater geometry utilizes a concentric ring configuration and consists of an inner disc-shaped contact terminal, a ring-shaped resistive heater element surrounding the disc-shaped contact terminal and an outer peripheral contact terminal surrounding the heater element. The heater is operated by means of an electrical current flowing in a radial direction through the circuit comprising the outer peripheral contact terminal, the annular resistive heater element and the inner contact terminal.
    Type: Grant
    Filed: November 24, 1976
    Date of Patent: July 25, 1978
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Frank A. Pizzarello, Theodore J. LaChapelle, Jr.
  • Patent number: 4091803
    Abstract: A transducer for optically detecting a cyclic phenomenon of variable frequency and supplying an electric signal corresponding to the frequency, comprises a light source for illuminating the site of the phenomenon and a detector for detecting variations in the level of light reflected from the site of the phenomenon and providing the required electric signal, the detector being a semiconductor opto-electronic cell and the light source being positioned within the detector.
    Type: Grant
    Filed: February 9, 1976
    Date of Patent: May 30, 1978
    Assignee: Thomas Orr
    Inventor: Russell Stuart Pinder
  • Patent number: 4089991
    Abstract: An improved method for providing electrical conductive paths in a Dewar flask is disclosed. A thin metal film is deposited over the side and top of the inner flask of the Dewar. Portions of the metal film are then selectively removed to provide electrical conductive paths which extend from the side on to the top of the inner flask.
    Type: Grant
    Filed: April 7, 1977
    Date of Patent: May 16, 1978
    Assignee: Honeywell Inc.
    Inventor: Gene A. Robillard
  • Patent number: 4088485
    Abstract: A xerographic plate and photoreceptor having improved speed and image resolution capability comprising a charge generating photoconductor layer, a trapping layer and a profile layer interposed between the trapping and charge generating layers; a suitable profile layer being obtained for xerographic purposes by utilizing materials from the charge generating and trapping layers having different band gaps but applied so as to obtain a gradation or gradient rather than a sharp interface.
    Type: Grant
    Filed: October 21, 1975
    Date of Patent: May 9, 1978
    Assignee: Xerox Corporation
    Inventors: Samuel W. Ing, Fred W. Schmidlin
  • Patent number: 4086555
    Abstract: An improved photoconductive sensor is provided which includes a substrate of calcium fluoride or barium fluoride in monocrystalline form upon which has been sputtered under controlled conditions a thin unannealed monocrystalline film having the formula Pb.sub.1-x Sn.sub.x Te where x = about 0-0.3. The conditions under which the film is deposited are controlled so that the film exhibits a cutoff wavelength between about 6.mu.m and about 15.mu.m, a photoconductive responsivity which may be as high as up to about 10.sup.3 V/watt at 77.degree. K and a detectivity peak value which may be as high as up to about 1.5 .times. 10.sup.10 cm-Hz.sup.1/2 /watt at frequencies above the 1/f noise frequency. The film also exhibits a fast response time of less than about 100 nanoseconds and is usually present in a thickness, for example about 1-2.mu.m, corresponding to high quantum efficiency and minimal contribution of unexcited film to detector noise.
    Type: Grant
    Filed: May 27, 1976
    Date of Patent: April 25, 1978
    Assignee: General Dynamics Corporation
    Inventors: Esther Krikorian, Michael J. Crisp
  • Patent number: 4085321
    Abstract: A method for obtaining increased flexibility and responsiveness in solid state switching devices to effect a change in voltage or field and a corresponding switching device for obtaining such result, wherein the charge transport component of the photoactivated switch is functionally separate and distinct from the photoconductive charge-generating component, the former being initially selected to provide the necessary changes with respect to voltage or field while simultaneously maintaining constant photoconductive parameters such as dark decay, spectral range, etc. in the latter component.
    Type: Grant
    Filed: June 8, 1976
    Date of Patent: April 18, 1978
    Assignee: Xerox Corporation
    Inventor: Philip O. Sliva
  • Patent number: 4053309
    Abstract: An electrophotographic camera is disclosed. The camera employs a novel photoconductive plate, the composition of which is disclosed together with the method of making same. In the camera, a photo image to be recorded is focused thrugh an optically transparent substrate and transparent electrode onto the back surface of a photoconductive layer. The charge-retentive surface of an electrographic recording paper is disposed adjacent the photoconductive layer and the conductive backing of the paper is connected to an electrode for impressing a charge transfer potential across the photoconductor layer and the charge-retentive layer of the paper. When the potential is impressed across the photoconductor, electrons liberated in the photoconductor by the photon image to be recorded are transferred to the charge-retentive surface of the recording paper to form a charge image of the object to be recorded. The charge image is subsequently developed by applying charged toner particles to the image for developing same.
    Type: Grant
    Filed: January 12, 1976
    Date of Patent: October 11, 1977
    Assignee: Varian Associates, Inc.
    Inventor: Guy A. Marlor
  • Patent number: 4053863
    Abstract: In an electrophotographic camera, a photon image to be recorded is focused through an optically transparent substrate and transparent electrode onto the back surface of a photoconductive layer. The charge-retentive surface of an electrographic recording paper is disposed adjacent the photoconductive layer and the conductive backing of the paper is connected to an electrode for impressing a charge transfer potential across the photoconductor layer and the charge-retentive layer of the paper. When the potential is impressed across the photoconductor, increased conduction caused in the photoconductor by the photon image to be recorded are establish a charge transfer to the charge-retentive surface of the recording paper to form a charge image of the object to be recorded. The charge image is subsequently developed by applying charged toner particles to the image for developing same.
    Type: Grant
    Filed: July 17, 1972
    Date of Patent: October 11, 1977
    Assignee: Varian Associates, Inc.
    Inventor: Guy A. Marlor
  • Patent number: 4026702
    Abstract: The electrophotographic properties of photoconductive elements sensitized by a cadmium sulfide-binder layer are improved by incorporating hydrophobic colloidal silica in the photoconductive layer.
    Type: Grant
    Filed: November 28, 1975
    Date of Patent: May 31, 1977
    Assignee: Oce-van der Grinten N.V.
    Inventors: Michiel van den Brink, Andreas C. Stoot
  • Patent number: 3996548
    Abstract: A photodetector is bonded to an electrically conductive substrate with an indium containing solder. An electrical insulating layer of a stable oxide which is wettable by indium provides electrical insulation between the electrically conductive substrate and the photodetector.
    Type: Grant
    Filed: November 19, 1975
    Date of Patent: December 7, 1976
    Assignee: Honeywell Inc.
    Inventor: John H. Chaffin, III
  • Patent number: 3990832
    Abstract: A multiple flashlamp array is designed having a plurality of lamps fired individually and in sequence and includes a plurality of static solid switching devices capable of being easily activated by radiant energy generated during flashing of the lamps. Initially, the switches have a high resistance ("off" condition) and after being activated by radiation, they undergo chemical conversion to a conductive state ("on" condition). The switches are prepared from compositions which impart improved shelf life under conditions of relatively high humidity at above normal ambient temperatures.
    Type: Grant
    Filed: September 29, 1975
    Date of Patent: November 9, 1976
    Assignee: General Electric Company
    Inventors: Robert L. Smialek, Mary S. Jaffe
  • Patent number: 3988612
    Abstract: Disclosed is a photodetector array of resistance variable light detectors and a method for manufacturing such an array. Electronic read-out circuitry is normally associated therewith.
    Type: Grant
    Filed: April 19, 1973
    Date of Patent: October 26, 1976
    Assignee: General Dynamics Corporation
    Inventor: John P. Palmer
  • Patent number: 3968006
    Abstract: To achieve constant brightness from the chlorine stage of a wood pulp bleaching system, the chlorine addition rate is controlled by two white light photosensors positioned, respectively, 1-5 minutes downstream of the chlorine addition point and immediately prior to the chlorine washers. A relative error signal from the late photosensor is cascaded upon the set-point of a signal differentiator for the early photosensor to generate a chlorine valve control signal. The photosensors comprise selenium photocells positioned against a transparent stock conduit window and reflection illuminated by a low power white light source positioned more remotely from the window than the photocell at a discreet offset angle relative thereto. The white light is directed past the photocells, through the windows and into the flow stream; the photocells being responsive to the relative magnitude of white light reflected from the wood pulp. The power generated from the photocell is correlated to the pulp brightness.
    Type: Grant
    Filed: February 3, 1975
    Date of Patent: July 6, 1976
    Assignee: Westvaco Corporation
    Inventor: William E. Zimmerman
  • Patent number: 3966470
    Abstract: As a photoconductive material there is provided a carrier having a coating thereon of a germanium-sulphur-lead alloy or a germanium-sulphur-tin alloy.
    Type: Grant
    Filed: June 3, 1974
    Date of Patent: June 29, 1976
    Assignee: VEB Pentacon Dresden
    Inventors: Adalbert Feltz, Johannes Opfermann, Bernd Voigt, Walter Seliger
  • Patent number: 3962669
    Abstract: An improved semiconductor device is described which utilizes stable, slow diffusing resilient contacts that also serve as a suspension support for a semiconductor body.
    Type: Grant
    Filed: July 24, 1974
    Date of Patent: June 8, 1976
    Assignee: Tyco Laboratories, Inc.
    Inventors: Gerald Entine, Frank C. Wilson, Richard Farrell
  • Patent number: 3958207
    Abstract: High quantum yields are provided by sandwiching an insulating layer in contact with a photoconductor between two electrodes. The sandwiched structure in conjunction with an applied electrical potential and excitation light provides an electrical switching device. Optionally, an imaging layer can be included between the photoconductive layer and one of the electrodes, and can be imaged with increased sensitivity.
    Type: Grant
    Filed: July 17, 1974
    Date of Patent: May 18, 1976
    Assignee: Xerox Corporation
    Inventor: Simpei Tutihasi