Photocathode Responsive To Phosphor Patents (Class 313/527)
  • Patent number: 11848180
    Abstract: Components of scientific analytical equipment. More particularly, ion detectors of the type which incorporate electron multipliers and modifications thereto for extending the operational lifetime or otherwise improving performance. The ion detector may be embodied in the form of a particle detector having one or more electron emissive surfaces and/or an electron collector surface therein, the particle detector being configured such that in operation the environment about the electron emissive surface(s) and/or the electron collector surface is/are different to the environment immediately external to the detector.
    Type: Grant
    Filed: March 22, 2019
    Date of Patent: December 19, 2023
    Assignee: ADAPTAS SOLUTIONS PTY LTD
    Inventors: Russell Jurek, Kevin Hunter
  • Patent number: 9360566
    Abstract: Provided is a radiation detector, including: a two-dimensional light receiving element including a plurality of pixels; and a scintillator layer having multiple scintillator crystals two-dimensionally arranged on a light receiving surface of the two-dimensional light receiving element, in which: the scintillator crystal includes two crystal phases, which are a first crystal phase including a material including a plurality of columnar crystals extending in a direction perpendicular to the light receiving surface of the two-dimensional light receiving element and having a refractive index n1, and a second crystal phase including a material existing between the plurality of columnar crystals and having a refractive index n2; and a material having a refractive index n3 is placed between adjacent scintillator crystals, the refractive index n3 satisfying a relationship of one of n1?n3?n2 and n2?n3?n1.
    Type: Grant
    Filed: July 18, 2012
    Date of Patent: June 7, 2016
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tatsuya Saito, Tatsuya Iwasaki, Nobuhiro Yasui, Toru Den
  • Patent number: 9316742
    Abstract: An ordering structure scintillator of scintillator and fabrication method is disclosed. The ordering structure scintillator of scintillator comprises: a tubular template, which consists of a plurality of thin film oxidized metal tubes; a plurality of scintillators, filled in the thin film oxidized metal tubes; and a package layer, formed on the surface of the tubular template for protecting the tubular template. In addition, through the fabrication method, the ordering structure scintillator of scintillator can be made by anodic treatment and die casting technology with low cost and rapid production; moreover, the film oxidized metal tubes of the tubular template can be further manufactured to nano tubes by adjusting electrolyte composition, electrolysis voltage, and processing time of anodic treatment, and the aperture size, the thickness and the vessel density of the nano tube can be controlled and ranged from 10 nm to 500 nm, 0.1 ?m to 1000 ?m, and 108 to 1012 tube/cm2, respectively.
    Type: Grant
    Filed: December 12, 2012
    Date of Patent: April 19, 2016
    Inventor: Chien-Chon Chen
  • Patent number: 7786445
    Abstract: A side tube includes a tube head, a funnel-shaped connection neck, and a tube main body, which are arranged along a tube axis and which are integrated together into the side tube. The size of a cross section of the tube head perpendicular to the tube axis is larger than the size of a cross section of the tube main body perpendicular to the tube axis. The radius of curvature of rounded corners of the tube head is smaller than the radius of curvature of rounded corners of the tube main body. The length of the tube head along the tube axis is shorter than the length of the tube main body along the tube axis. One surface of a faceplate is connected to the tube head. A photocathode is formed on the surface of the faceplate in its area located inside the tube head.
    Type: Grant
    Filed: September 17, 2007
    Date of Patent: August 31, 2010
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Teruhiko Yamaguchi, Suenori Kimura, Minoru Suzuki, Yoshitaka Nakamura
  • Patent number: 7728292
    Abstract: An ion detector includes collision surfaces for converting both positively and negatively charged ions into emitted secondary electrons. Secondary electrons may be detected using an electron detector, than may, for example include an electron multiplier. Conveniently, secondary electrons (or electrons emitted by the multiplier) may be detected using an electron pulse counter.
    Type: Grant
    Filed: August 28, 2006
    Date of Patent: June 1, 2010
    Assignee: Ionics Mass Spectrometry Group Inc.
    Inventors: Charles Jolliffe, Lisa Cousins, Gholamreza Javahery
  • Patent number: 7525249
    Abstract: In an electron tube, an insulating tube protrudes inside an envelope. One end of the insulating tube is connected to the envelope. An avalanche photo diode (APD) is provided on the other end of the insulating tube. A ground voltage is applied to the envelope and a positive high voltage is applied to the APD. Photoelectrons which are emitted in response to an incident light on a photocathode are converged by an electrical field in the envelope and enter the APD. Thereafter, the incident photoelectrons are amplified and detected. Since a positive high voltage is not exposed to the envelope, the electron tube can easily be handled and is excellent in safety.
    Type: Grant
    Filed: September 9, 2004
    Date of Patent: April 28, 2009
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Motohiro Suyama, Hiroyuki Kyushima, Suenori Kimura, Yasuharu Negi, Atsuhito Fukasawa, Yoshihiko Kawai, Atsushi Uchiyama, Yasuyuki Egawa
  • Patent number: 7486021
    Abstract: A photocathode is formed on a predetermined portion of the internal surface of an envelope of an electric tube. An avalanche photodiode (APD) is provided inside the envelope. The APD is surrounded by a cover and a tubular inner wall. A manganese bead and an antimony bead serving as evaporation sources are disposed in the vicinity outside the inner wall. The manganese bead and the antimony bead are surrounded by a tubular outer wall. The manganese bead and the antimony bead generate metal vapor to thereby form the photocathode. In forming the photocathode, the cover, inner wall, outer wall prevent the metal vapor from being deposited on the APD or an unintended portion inside the electron tube.
    Type: Grant
    Filed: September 9, 2004
    Date of Patent: February 3, 2009
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Yasuhara Negi, Atsushi Uchiyama, Yasuyuki Egawa, Hiroyuki Kyushima, Suenori Kimura, Motohiro Suyama
  • Patent number: 7417235
    Abstract: A multi-purpose efficient charge particle detector that by switching bias voltages measures either secondary ions, or secondary electrons (SE) from a sample, or secondary electrons that originate from back scattered electrons (SE3), is described. The basic version of the detector structure and two stripped down versions enable its use for the following detection combinations: The major version is for measuring secondary ions, or secondary electrons from the sample, or secondary electrons due to back-scattered electrons that hit parts other than the sample together or without secondary electrons from the sample. Measuring secondary ions or secondary electrons from the sample (no SE3). Measuring secondary electrons from the sample and/or secondary electrons resulting from back-scattered electrons hitting objects other than the sample (no ions).
    Type: Grant
    Filed: May 11, 2006
    Date of Patent: August 26, 2008
    Assignee: El-Mul Technologies, Ltd.
    Inventors: Armin Schon, Eli Cheifetz, Semyon Shofman
  • Patent number: 7251400
    Abstract: A limiter device is used as a fiber optic faceplate (FOFP) night vision goggle for limiting light or laser induced damage on a vacuum side of the FOFP. The limiter device includes a plurality of longitudinally extending optical fibers, each bundled to each other to form a light input surface on an external side of the FOFP and a light output surface on the vacuum side of the FOFP. The optical fibers include fiber optic cores and a glass cladding surrounding each of the cores. A portion of the glass cladding is replaced by an optical absorber material extending longitudinally away from the light input surface. The optical absorber material may extend longitudinally about 1-20 microns away from the light input surface.
    Type: Grant
    Filed: June 13, 2005
    Date of Patent: July 31, 2007
    Assignee: ITT Manufacturing Enterprises, Inc.
    Inventor: Niels Frederick Jacksen
  • Patent number: 6992441
    Abstract: A photocathode manufacturing intermediary article (24) includes a substrate layer (26), and an active layer (20) that is carried by the substrate layer (26). The active layer (20) includes photoemissive alkali antimonide material that is epitaxially grown on the substrate (26).
    Type: Grant
    Filed: September 13, 2004
    Date of Patent: January 31, 2006
    Assignee: Litton Systems, Inc.
    Inventors: Robert Glosser, Joseph P. Estrera, Loig E. Bourree
  • Patent number: 6762555
    Abstract: A photomultiplier tube has a side tube with a stem plate fixed on one end and a faceplate fixed on the other. The side tube is formed of metal, and at least the portion of the stem plate contacting the metal side tube is formed of metal. The side tube and stem plate are fused together by laser welding or electron beam welding to form an airtight vessel, such that the outer edge of the stem plate does not protrude further externally than the outer surface of the side tube.
    Type: Grant
    Filed: November 28, 2000
    Date of Patent: July 13, 2004
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hiroyuki Kyushima, Akira Atsumi, Hideki Shimoi, Tomoyuki Okada, Masuo Ito
  • Patent number: 6657385
    Abstract: A diamond transmission dynode and photocathode are described which include a thin layer of a crystalline semiconductive material. The semiconductive material is preferably textured with a (100) orientation. Metallic electrodes are formed on the input and output surfaces of the semiconductive material so that a bias potential can be applied to enhance electron transport through the semiconductive material. An imaging device and a photomultiplier utilizing the aforesaid transmission dynode and/or photocathode are also described.
    Type: Grant
    Filed: June 20, 2001
    Date of Patent: December 2, 2003
    Assignee: Burle Technologies, Inc.
    Inventors: Charles M. Tomasetti, Robert Caracciolo, Charles B. Beetz, David R. Winn
  • Patent number: 6635990
    Abstract: A display device comprising a primary light-emissive region, a light-sensitive region and a secondary light-emissive region, wherein: the primary light-emissive region comprises an organic light-emissive material and a pair of electrodes arranged to apply an electric field across the light-emissive material to cause it to emit light; the light-sensitive region comprises a photocathode responsive to light from the primary light-emissive region to release charged particles towards the secondary light-emissive region; sand the secondary light-emissive region comprises a phosphorescent material excitable by the charged particles from the light-sensitive region to emit light.
    Type: Grant
    Filed: June 15, 1999
    Date of Patent: October 21, 2003
    Assignee: Cambridge Display Technologies
    Inventor: Karl Pichler
  • Patent number: 6628072
    Abstract: A method and apparatus for increasing the quantum efficiency of a photomultiplier tube by providing a photocathode with an increased surface-to-volume ratio. The photocathode includes a transparent substrate, upon one major side of which is formed one or more large aspect-ratio structures, such as needles, cones, fibers, prisms, or pyramids. The large aspect-ratio structures are at least partially composed of a photoelectron emitting material, i.e., a material that emits a photoelectron upon absorption of an optical photon. The large aspect-ratio structures may be substantially composed of the photoelectron emitting material (i.e., formed as such upon the surface of a relatively flat substrate) or be only partially composed of a photoelectron emitting material (i.e., the photoelectron emitting material is coated over large aspect-ratio structures formed from the substrate material itself.
    Type: Grant
    Filed: May 14, 2001
    Date of Patent: September 30, 2003
    Assignee: Battelle Memorial Institute
    Inventors: Richard A. Craig, Mary Bliss
  • Patent number: 6624414
    Abstract: The present invention comprises an enhanced vision device having an image intensifier tube (16) with an input end (17a) and an output end (17b) with an IR phosphor (19) deposited on the input end (17a) of the image intensifier tube (16). The IR phosphor (19) produces photons in response to light of wavelengths that would be undetectable by the image intensifier tube (16).
    Type: Grant
    Filed: August 25, 1999
    Date of Patent: September 23, 2003
    Assignee: Litton Systems, Inc.
    Inventor: John W. Glesener
  • Patent number: 6614180
    Abstract: An apparatus and method for detecting ionizing radiation are presented. The apparatus includes a scintillator adapted to convert incident ionizing radiation into light; a photocathode adapted to release photoelectrons in dependence on the light; an electron avalanche amplifier adapted to avalanche amplify the photoelectrons; and a readout arrangement adapted to detect the avalanche amplified electrons. The electron avalanche amplifier in one implementation is a gaseous avalanche amplifier including an array of amplification regions. A protective layer is provided to prevent the avalanche gas from coming into contact with the photocathode.
    Type: Grant
    Filed: October 30, 2000
    Date of Patent: September 2, 2003
    Assignee: XCounter AB
    Inventors: Tom Francke, Vladimir Peskov
  • Patent number: 6563264
    Abstract: This photocathode comprises: InP substrate 1; InAsx2P1−x2(0<x2<1) buffer layer 2; Inx1Ga1−x1As (1>x1>0.53) light-absorbing layer 3; InAsx3P1−x3 (0<x3<1) electron-emitting layer 4; InAsx3P1−x3 contact layer 5 formed on the electron-emitting layer 4; active layer 8 of an alkali metal or its oxide or fluoride formed on the exposed surface of electron-emitting layer 4; and electrodes 6 and 7.
    Type: Grant
    Filed: April 27, 2001
    Date of Patent: May 13, 2003
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Minoru Niigaki, Toru Hirohata, Tomoko Mochizuki, Hirofumi Kan
  • Patent number: 6437491
    Abstract: The present invention comprises a photon detector and image generator, which includes a photocathode that receives photons from an image. The photocathode discharges electrons in response to the received photons. A microchannel plate with an unfilmed input face and an output face receives the electrons from the photocathode and produces secondary emission electrons which are emitted from the output face. A display receives the secondary electrons and displays a representation of the image. The photon detector and image generator has a lifetime of more than 7,500 hours.
    Type: Grant
    Filed: June 4, 1999
    Date of Patent: August 20, 2002
    Assignee: Northrop Grumman Corporation
    Inventors: Joseph P. Estrera, Anthony J. Nico, Keith T. Passmore, Timothy W. Sinor, Robert H. Smithson
  • Patent number: 6437339
    Abstract: A flat panel x-ray imager includes a gain layer (charge multiplication layer) that facilitates imaging at low x-ray exposure levels. The gain layer can be a gas chamber or a solid state material operating in an avalanche mode.
    Type: Grant
    Filed: March 22, 2001
    Date of Patent: August 20, 2002
    Assignee: Hologic, Inc.
    Inventors: Denny L. Y. Lee, Lawrence K. F. Cheung, Andrew P. Smith
  • Publication number: 20020041154
    Abstract: A diamond transmission dynode and photocathode are described which include a thin layer of a crystalline semiconductive material. The semiconductive material is preferably textured with a (100) orientation. Metallic electrodes are formed on the input and output surfaces of the semiconductive material so that a bias potential can be applied to enhance electron transport through the semiconductive material. An imaging device and a photomultiplier utilizing the aforesaid transmission dynode and/or photocathode are also described.
    Type: Application
    Filed: June 20, 2001
    Publication date: April 11, 2002
    Inventors: Charles M. Tomasetti, Robert Caracciolo, Charles B. Beetz, David R. Winn
  • Publication number: 20020011787
    Abstract: This photocathode comprises: InP substrate 1; InAsx2P1−x2(0<x2<1) buffer layer 2; Inx1Ga1−x1As (1>x1>0.53) light-absorbing layer 3; InAsx3P1−x3 (0<x3<1) electron-emitting layer 4; InAsx3P1−x3 contact layer 5 formed on the electron-emitting layer 4; active layer 8 of an alkali metal or its oxide or fluoride formed on the exposed surface of electron-emitting layer 4; and electrodes 6 and 7.
    Type: Application
    Filed: April 27, 2001
    Publication date: January 31, 2002
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Minoru Niigaki, Toru Hirohata, Tomoko Mochizuki, Hirofumi Kan
  • Patent number: 6169360
    Abstract: The present invention assures a satisfactory adhesiveness of an input screen 13 of an X-ray image intensifier, high resolution of an output image and brightness uniformity as required, by configuring an aluminum or aluminum alloy substrate 21 so to have a concave surface with minute irregularities of the substrate material removed by burnishing, excepting gentle irregularities 21c without directivity which are caused by pressing. The gentle irregularities 21c of the substrate 21 preferably have an average length L in a range of 50 &mgr;m to 300 &mgr;m between the neighboring bottoms and an average height H in a range of 0.3 &mgr;m to 4.0 &mgr;m from peaks to bottoms. The invention improves resolution with light on the substrate surface suppressed from being scattered, and decreases image noises which are caused by the minute irregularities.
    Type: Grant
    Filed: July 17, 1998
    Date of Patent: January 2, 2001
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Electronic Engineering Corporation
    Inventors: Kazutoshi Tanno, Yoshinobu Sekijima, Hitoshi Yamada, Takashi Noji
  • Patent number: 5680007
    Abstract: A photoelectric emission surface which is excellent in stability and reproducibility of photoelectric conversion characteristics and has a structure capable of obtaining a high photosensitivity is provided. A predetermined voltage is applied between an upper surface electrode and a lower surface electrode by a battery. Upon application of this voltage, a p-n junction formed between a contact layer and an electron emission layer is reversely biased. A depletion layer extends from the p-n junction into the photoelectric emission surface, and an electric field is formed in the electron emission layer and a light absorbing layer in a direction for accelerating photoelectrons. When incident light is absorbed in the light absorbing layer to excite photoelectrons, the photoelectrons are accelerated by the electric field toward the emission surface.
    Type: Grant
    Filed: July 27, 1995
    Date of Patent: October 21, 1997
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Minoru Niigaki, Toru Hirohata, Tomoko Suzuki, Masami Yamada
  • Patent number: 5646477
    Abstract: An X-ray image intensifier that includes a vacuum envelope having a metal X-ray input window and an input screen formed on the inner surface of the X-ray input window, a focusing electrode, an anode, and an output screen arranged in the vacuum envelope along the traveling direction of electrons generated from the input screen. The X-ray input window has a rough, surface-hardened layer on the side on which the input screen is formed. The input screen includes a phosphor layer adjacent to the rough, surface-hardened layer and a photocathode formed on the phosphor layer.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: July 8, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Shirofumi Yamagishi
  • Patent number: 5587621
    Abstract: In order to increase the sensitivity of an image intensifier tube, the efficiency with which an electron image is formed from radiation of a first wavelength is increased. Radiation of the first wavelength is converted into radiation of a second wavelength by means of a conversion screen provided with a scintillation layer, and radiation of the second wavelength releases electrons from a photocathode which is sensitive to the second wavelength. Loss of radiation of a second wavelength, incurred because a part of this radiation does not reach the photocathode, is reduced. Radiation of the second wavelength which is not emitted in the direction of the photocathode is recaptured by providing the conversion screen with a metallic reflecting intermediate layer.
    Type: Grant
    Filed: February 8, 1995
    Date of Patent: December 24, 1996
    Assignee: U.S. Philips Corporation
    Inventor: Johannes K. E. Colditz
  • Patent number: 5349178
    Abstract: An x-ray image intensifier has an evacuated housing, an input luminescent screen, electron optics, and an image sensor disposed inside the housing at a side of the housing opposite the input luminescent screen. The image sensor is covered by a protective layer which effects a deceleration of the incident electrons, the protective layer being applied on that side of the image sensor facing the input luminescent screen.
    Type: Grant
    Filed: June 22, 1993
    Date of Patent: September 20, 1994
    Assignee: Siemens Aktiengesellschaft
    Inventors: Detlef Mattern, Arnulf Oppelt, Hartmut Sklebitz
  • Patent number: 5338926
    Abstract: An X-ray imaging tube has an input phosphor screen including a substrate, a discontinuous phosphor layer formed on the substrate, and a continuous phosphor layer formed on the discontinuous phosphor layer. The discontinuous phosphor layer consists of a large number of columnar crystals separated from each other and containing a substance for absorbing light emitted from a phosphor upon incidence of an X-ray. Light-absorbing layers containing a compound of the substance and having a concentration of the element higher on outer surfaces thereof than that in interiors thereof are formed on adjacent side surfaces of the columnar crystals such that the light-absorbing layers are not present at an interface between the discontinuous phosphor layer and the continuous phosphor layer. The gap between the adjacent side surfaces of the columnar crystals is 0.1 .mu.m or more.
    Type: Grant
    Filed: May 22, 1992
    Date of Patent: August 16, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Atsuya Yoshida
  • Patent number: 5311098
    Abstract: An interference photocathode includes a reflective substrate and interference layers disposed on said reflective substrate for selectively enhancing a first photoelectric yield of said photocathode when irradiated by radiation having a first wavelength relative to a second photoelectric yield of said photocathode when irradiated by radiation having a second wavelength. In one embodiment, the interference layers include a dielectric layer having a wavelength dependent effective thickness disposed on said reflective substrate such that said effective thickness for radiation having said first wavelength is an odd multiple of a quarter of said first wavelength and said effective thickness for radiation having said second wavelength is an even multiple of a quarter of said second wavelength. In another embodiment, the dielectric layer includes a layer of electrically conductive material and a dielectric material disposed between said layer of electrically conductive material and said reflective substrate.
    Type: Grant
    Filed: May 26, 1992
    Date of Patent: May 10, 1994
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: John F. Seely, William R. Hunter
  • Patent number: 5268570
    Abstract: An improved photocathode for use in a night vision system, comprising a glass face plate, an AlInAs window layer having an anti-reflection and protective coating bonded to the face plate, an InGaAs active layer epitaxially grown to the window layer, and a chrome electrode bonded to the face plate, the window layer, and the active layer providing an electrical contact between the photocathode and the night vision system, whereby an optical image illuminated into the face plate results in a corresponding electron pattern emitted from the active layer.
    Type: Grant
    Filed: December 20, 1991
    Date of Patent: December 7, 1993
    Assignee: Litton Systems, Inc.
    Inventor: Hyo-Sup Kim
  • Patent number: 5093566
    Abstract: Via the shape of the photocathode surface and the geometry and potential distribution of electrodes of the electron-optical system, an X-ray image intensifier tube is optimized for reduction of the transit time variance for photoelectrons from the photocathode surface to a photoelectron detector. The photoelectron detector, on which an image need not be formed in this case, has, for example, a comparatively small entrance surface and is arranged in or near a cross-over of the photoelectrons.
    Type: Grant
    Filed: June 29, 1990
    Date of Patent: March 3, 1992
    Assignee: U.S. Philips Corporation
    Inventor: Gerardus Van Aller
  • Patent number: 5029247
    Abstract: An X-ray image intensifier includes an input screen for converting incident X-rays into photoelectrons, and an output screen for converting the photoelectrons into visible light. The input screen includes a phosphor layer. The phosphor layer has a large number of columnar crystals of a phosphor which have end faces constituting a smooth surface facing the output screen. A low-refractive-index layer is formed on the phosphor layer and made of a material having a refractive index smaller than a refractive index of the phosphor, with respect to the light having a specified wavelength, at which the fluorescence of the phosphor is the most intensive. A photoemissive layer is formed directly or indirectly on the low-refractive-index layer.
    Type: Grant
    Filed: May 17, 1990
    Date of Patent: July 2, 1991
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hidero Anno, Katsuhiro Ono
  • Patent number: 5008591
    Abstract: The entrance screen in an X-ray image intensifier includes an intermediate layer of a material which selectively absorbs photon energy. As a result, the speed of the photo-electrons is substantially reduced, thus improving the imaging. By introducing a radial variation of the absorption in the intermediate layer, vignetting-compensation can also be realized without substantial loss of sensitivity and resolution for the central portion of the tube. The resolution at the periphery of the tube can thus be substantially improved.
    Type: Grant
    Filed: January 8, 1990
    Date of Patent: April 16, 1991
    Assignee: U.S. Philips Corp.
    Inventors: Johnny van der Velden, Theodorus F. van Bergen, August L. H. Simons, Johannes K. E. Colditz, Martinus A. C. Ligtenberg, Franciscus M. Dreesen
  • Patent number: 4982136
    Abstract: An aluminum substrate which supports a scintillator transforms X-rays into visible or nearly visible light radiation which is converted into a flux of electrons by means of a photocathode. The flux produces a visible image on an exit screen through electro-optical means. A layer which absorbs the light radiation emitted by the scintillator in the direction of the aluminium substrate is inserted between the aluminium substrate and the scintillator, the absorbing layer consisting of a material chosen from the following materials: titanium nitride, cadmium sulphide, (Cu, OhI.sub.2). A layer having a low optical index can be inserted between the scintillator and the photocathode. A chemical barrier may also be inserted between the scintillator and the photocathode. An electrically conductive and optically transparent layer can be inserted between the photocathode and the chemical barrier.
    Type: Grant
    Filed: November 21, 1988
    Date of Patent: January 1, 1991
    Assignee: U.S. Philips Corporation
    Inventors: Pierre M. Dolizy, deceased, by Francois Charpail, legal representative
  • Patent number: 4950952
    Abstract: The present invention provides a photocathode which is formed on a substrate consisting of polycrystalline members, and which mainly consists of a semimetal, manganese or silver, and one or a plurality of alkaline metals, characterized in that the photocathode is formed on an alkaline metal oxide layer formed on the substrate, and a composition ratio of the semimetal, manganese or silver, and the one or a plurality of alkaline metals is stoichiometric or almost stoichiometric. The photocathode of the present invention has high sensitivity and can stably maintain the sensitivity for a long period of time.
    Type: Grant
    Filed: September 15, 1989
    Date of Patent: August 21, 1990
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yoshimitsu Aramaki
  • Patent number: 4935617
    Abstract: An X-ray image intensifier comprising a vacuum envelope and an input screen having an improved sensitivity and including a substrate disposed on the X-ray input side of the vacuum envelope, a phosphor layer formed on the substrate and a photocathode formed on the phosphor layer. The phosphor layer consists of columnar crystals extending in a direction perpendicular to the substrate surface. The tip portions of the columnar crystals are deformed to close the upper portion of the clearances formed between the columnar crystals.
    Type: Grant
    Filed: February 27, 1989
    Date of Patent: June 19, 1990
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hidero Anno, Katsuhiro Ono
  • Patent number: 4831249
    Abstract: The separating layer between the luminescent layer and the photocathode of the entrance screen in an X-ray image intensifier tube is formed by a layer which has a suitable optical transmission, a suitable chemical inertia, a suitable tightness and a strongly bridging character and which is deposited by means of a plasma CVD technique, so that all requirements to be imposed on a separating layer can be satisfied without causing a substantial loss of efficiency. By variation of the material composition, measured across the thickness of the layer, an optimum optical transition can be realized between the luminescent layer and the photocathode.
    Type: Grant
    Filed: October 16, 1987
    Date of Patent: May 16, 1989
    Assignee: U.S. Philips Corporation
    Inventors: Johny W. Van Der Velden, Willem H. Diemer
  • Patent number: 4740683
    Abstract: An X-ray image intensifier includes an input surface and an output surface facing the input surface. The input surface has a base and a phosphor layer formed on the base and having a predetermined effective radius. The phosphor layer includes a thickest portion which has a thickness about 105 to 115% of a thickness of a center of the layer and is located in a region spaced from the center toward the periphery of the layer by a distance about 60 to 80% of the effective radius. The phosphor layer is formed so that the thickness is gradually increased from the center to the thickest portion and a region between the thickest portion and the periphery of the layer has a thickness about 50 to 100% of the thickness of the thickest portion.
    Type: Grant
    Filed: March 30, 1987
    Date of Patent: April 26, 1988
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Noji, Shigeharu Kawamura
  • Patent number: 4730141
    Abstract: An imaging tube particularly useful in providing a visible image corresponding to an incident infrared image in which a reflective photocathode is used to provide an electron image corresponding to the infrared image, and in which the incident image rays and the ultimate image rays move along different directions.
    Type: Grant
    Filed: March 21, 1986
    Date of Patent: March 8, 1988
    Assignee: Galileo Electro-Optics Corp.
    Inventor: Christopher H. Tosswill
  • Patent number: 4709140
    Abstract: A high speed light detection tube consists of a planar photoelectron source of transparent type, a photoelectron collection electrode arranged in parallel with the photoelectron source and an acceleration electrode of transmission type arranged in parallel with the photoelectron source in a space between the photoelectron source and the photoelectron collection electrode. The potential distribution has been set so that the photoelectrons passing through the acceleration electrode can be incident on the photoelectron collection electrode at a constant speed or near value.
    Type: Grant
    Filed: July 17, 1986
    Date of Patent: November 24, 1987
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventor: Koichiro Oba
  • Patent number: 4698544
    Abstract: An imaging tube for amplifying and observing a diminished light image and a streaking tube for analyzing the light intensity distributions of light sources with elapsing of time. In order to avoid adhesion of alkali metal to the micro-channel-plate in fabrication of the imaging tube and to avoid adhesion of alkali metal to the deflection electrode in the streaking tube, a separation wall and a lid movable on the separation wall are used.
    Type: Grant
    Filed: January 30, 1986
    Date of Patent: October 6, 1987
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Katsuyuki Kinoshita, Yoshiji Suzuki
  • Patent number: 4645971
    Abstract: The thickness of the layer of luminescent material on the edges of the screen at approximately 1/10.degree. from the edge of the image field is approximately 15 to 25% smaller than its thickness at the center of the screen. Thus the length of the x-ray path within the luminescent material is substantially the same irrespective of the angle of incidence of the x-rays on the screen and, when the x-ray energy varies, the sensitivity at all points of the screen varies substantially in the same manner. The screen in accordance with the invention is primarily employed in digital radiology systems in which the same image is produced several times by utilizing different x-ray energies.
    Type: Grant
    Filed: April 23, 1984
    Date of Patent: February 24, 1987
    Assignee: Thomson-CSF
    Inventor: Jean Ricodeau
  • Patent number: 4563614
    Abstract: A photocathode arrangement comprises a body of semiconductor material, such as gallium arsenide which is bonded to a fiber optic face plate. A thin anti-reflection coating of silicon nitride is positioned between the body and the plate and forms an integral part of the bond. The properties of the glasses from which the fiber optic face plate is made are carefully chosen to minimize crystal dislocations which can be introduced into the body of gallium arsenide when it is bonded to the face plate. Such crystal dislocations can seriously impair the performance of the photocathode. It has been found that it is advantageous to use a glass having an annealing temperature of about 575.degree. C. or less. Because of high temperature processing steps, its softening temperature must be about 680.degree. C. or greater. The photocathode arrangement so formed is intended to constitute the input port of an image intensifier.
    Type: Grant
    Filed: January 24, 1985
    Date of Patent: January 7, 1986
    Assignee: English Electric Valve Company Limited
    Inventor: Jonathan R. Howorth
  • Patent number: 4475032
    Abstract: A conversion screen such as is used for X-ray image intensifier screens, X-ray image intensifier tubes, cathode-ray tubes, image pick-up tubes, X-ray electrography, fluorescent lamps and the like is formed by the deposition of a layer of conversion material on a carrier (19) via a melting space (7) which is preferably heated by means of a plasma arc. This method of deposition offers very robust screens with a high density and also allows the filling of recesses in a carrier with conversion material, so that structured conversion screens can be formed.
    Type: Grant
    Filed: June 7, 1982
    Date of Patent: October 2, 1984
    Assignee: U.S. Philips Corporation
    Inventors: Theo J. A. Popma, Gerhardus A. Te Raa, Adrianus T. Vink
  • Patent number: 4447721
    Abstract: An x-ray image intensifier tube for medical x-ray diagnostic use having a tube envelope, an inwardly concave, iron nickel, chromium alloy input window, an output display screen, a scintillator photocathode screen suspended within the envelope and in between the input window and the output screen, and a glass output window.
    Type: Grant
    Filed: July 31, 1981
    Date of Patent: May 8, 1984
    Assignee: Diagnostic Information, Inc.
    Inventor: Shih-Ping Wang
  • Patent number: 4398118
    Abstract: In an X-ray image intensifier consisting of a scintillator screen associated with a photocathode, an electron-optical system and an output screen on which a strong visible image appears, resolution is improved by providing the scintillator screen, formed by a layer of cesium iodide doped with sodium deposited onto the substrate, a structure of needles approximately micrometers in diameter which are kept in the form of separate needles during the subsequent heat treatment by virtue of the presence of silicon oxide in the cesium iodide lattice.
    Type: Grant
    Filed: April 29, 1981
    Date of Patent: August 9, 1983
    Assignee: Thomson - CSF
    Inventors: Jean-Pierre Galves, Jean-Marie Gutierrez
  • Patent number: 4396853
    Abstract: An image intensifier tube comprising a sealed envelope having therein means for controllably liberating oxygen within the envelope, and an input screen including an oxygen conditioned layer of fluorescent material and an overlying layer of photoemissive material which may be oxidized to improve the photon-to-electron conversion efficiency of the input screen.A method of improving the conversion efficiency of an image intensifier tube input screen including the steps of exposing a layer of fluorescent material to oxygen prior to the deposition of an overlying layer of photoemissive material, and subsequently exposing the layer of photoemissive material to oxygen, if desired, after the tube envelope has been sealed.
    Type: Grant
    Filed: August 18, 1980
    Date of Patent: August 2, 1983
    Assignee: The Machlett Laboratories, Incorporated
    Inventor: James R. Caraher
  • Patent number: RE31691
    Abstract: A panel shaped, proximity type, x-ray image intensifier tube for medical x-ray diagnostic use having all linear components and yet a high brightness gain, in the range of 500 to 20,000 cd-sec/m.sup.2 -R, the tube being comprised of a rugged metallic tube envelope, an inwardly concave, iron, nickel, chromium alloy input window, a full size output display screen, a halide activated alkaline-halide scintillator photocathode screen suspended on insulators within the envelope and in between the input window and the output screen, and a high Z glass output window to reduce x-ray backscatter inside and outside of the tube. The tube can be used in a direct view, photofluorographic mode, in a radiographic camera system and with a remote view T.V. system.
    Type: Grant
    Filed: August 29, 1980
    Date of Patent: October 2, 1984
    Assignee: Diagnostic Information, Inc.
    Inventor: Shih-Ping Wang