Patents by Inventor Takayuki Ohmura

Takayuki Ohmura 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: 8975592
    Abstract: An ion detector 1A for detecting positive ions is provided with a chamber 2 having an ion entrance 3 which allows positive ions to enter, a conversion dynode 9 which is disposed in the chamber 2 and to which a negative potential is applied, and an avalanche photodiode 30 that is disposed in the chamber 2 and has an electron incident surface 30a which is opposed to the conversion dynode 9 and also into which secondary electrons emitted from the conversion dynode 9 are made incident. The electron incident surface 30a is located closer to the conversion dynode 9 than a positioning part 14 which supports the avalanche photodiode 30 in the grounded chamber 2.
    Type: Grant
    Filed: January 18, 2013
    Date of Patent: March 10, 2015
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hiroshi Kobayashi, Motohiro Suyama, Masahiro Kotani, Takayuki Ohmura
  • Patent number: 8866071
    Abstract: An ion detector for detecting positive ions and negative ions, includes a housing provided with an ion entrance to make the positive ions and the negative ions enter, a conversion dynode which is disposed in the housing and to which a negative potential is applied, a scintillator which is disposed in the housing and has an electron incident surface which is opposed to the conversion dynode and into which secondary electrons emitted from the conversion dynode are made incident, a conductive layer which is formed on the electron incident surface and to which a positive potential is applied, and a photodetector which detects light emitted by the scintillator in response to incidence of the secondary electrons.
    Type: Grant
    Filed: May 24, 2013
    Date of Patent: October 21, 2014
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Masahiro Kotani, Takayuki Ohmura, Motohiro Suyama, Hiroshi Kobayashi
  • Publication number: 20130256539
    Abstract: An ion detector for detecting positive ions and negative ions, includes a housing provided with an ion entrance to make the positive ions and the negative ions enter, a conversion dynode which is disposed in the housing and to which a negative potential is applied, a scintillator which is disposed in the housing and has an electron incident surface which is opposed to the conversion dynode and into which secondary electrons emitted from the conversion dynode are made incident, a conductive layer which is formed on the electron incident surface and to which a positive potential is applied, and a photodetector which detects light emitted by the scintillator in response to incidence of the secondary electrons.
    Type: Application
    Filed: May 24, 2013
    Publication date: October 3, 2013
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Masahiro KOTANI, Takayuki OHMURA, Motohiro SUYAMA, Hiroshi KOBAYASHI
  • Patent number: 8466413
    Abstract: An ion detector for detecting positive ions and negative ions, includes a housing provided with an ion entrance to make the positive ions and the negative ions enter, a conversion dynode which is disposed in the housing and to which a negative potential is applied, a scintillator which is disposed in the housing and has an electron incident surface which is opposed to the conversion dynode and into which secondary electrons emitted from the conversion dynode are made incident, a conductive layer which is formed on the electron incident surface and to which a positive potential is applied, and a photodetector which detects light emitted by the scintillator in response to incidence of the secondary electrons.
    Type: Grant
    Filed: July 28, 2011
    Date of Patent: June 18, 2013
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Masahiro Kotani, Takayuki Ohmura, Motohiro Suyama, Hiroshi Kobayashi
  • Patent number: 8330364
    Abstract: The present invention relates to a photomultiplier that realizes a significant improvement of response time characteristics by a structure enabling mass production. The photomultiplier comprises a sealed container, and, in the sealed container, a photocathode, an electron multiplier section, and an anode are respectively disposed. The electron multiplier section includes multiple stages of dynode units, and each of the multiple stages of dynode units is fixed with one end of the associated dynode pin while being electrically connected thereto. In particular, the dynode pin, whose one ends are fixed to the multiple stages of dynode units, are held within an effective region of the electron multiplier section contributing to secondary electron multiplication, when the electron multiplier section is viewed from the photocathode side.
    Type: Grant
    Filed: February 19, 2009
    Date of Patent: December 11, 2012
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Takayuki Ohmura, Hiroyuki Kyushima, Hideki Shimoi, Tsuyoshi Kodama
  • Publication number: 20120025085
    Abstract: An ion detector for detecting positive ions and negative ions, includes a housing provided with an ion entrance to make the positive ions and the negative ions enter, a conversion dynode which is disposed in the housing and to which a negative potential is applied, a scintillator which is disposed in the housing and has an electron incident surface which is opposed to the conversion dynode and into which secondary electrons emitted from the conversion dynode are made incident, a conductive layer which is formed on the electron incident surface and to which a positive potential is applied, and a photodetector which detects light emitted by the scintillator in response to incidence of the secondary electrons.
    Type: Application
    Filed: July 28, 2011
    Publication date: February 2, 2012
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Masahiro KOTANI, Takayuki OHMURA, Motohiro SUYAMA, Hiroshi KOBAYASHI
  • Patent number: 8013294
    Abstract: This ion detector includes an MCP and a plurality of planar dynodes respectively having a plurality of slits. The plurality of planar dynodes are stacked via spacers parallel to an electron output plane of the MCP, and the first stage planar dynode is opposed parallel to the electron output plane. In accordance with this ion detector, it is possible to obtain output signals having the linearity reaching mV order, and to shorten its pulse width to approximately 600 ps.
    Type: Grant
    Filed: October 28, 2009
    Date of Patent: September 6, 2011
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Motohiro Suyama, Takayuki Ohmura, Hiroshi Kobayashi
  • Patent number: 7990064
    Abstract: The present invention relates to a photomultiplier that realizes significant improvement of response time properties with a structure enabling mass production. In the sealed container, a photocathode, a dynode unit including at least one dynode set, and preferably dynode sets of two series, a focusing electrode unit arranged between the photocathode and the dynode unit are housed. The focusing electrode unit is set to the same potential as the second dynode arranged at a position where secondary electrons from said first dynode, which emits secondary electrons in response to incidence of photoelectrons, arrive, and is provided with partitioning plates partitioning the second dynode into two in a longitudinal direction of the second dynode.
    Type: Grant
    Filed: November 8, 2006
    Date of Patent: August 2, 2011
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Takayuki Ohmura, Teruhiko Yamaguchi
  • Publication number: 20110095174
    Abstract: This ion detector includes an MCP and a plurality of planar dynodes respectively having a plurality of slits. The plurality of planar dynodes are stacked via spacers parallel to an electron output plane of the MCP, and the first stage planar dynode is opposed parallel to the electron output plane. In accordance with this ion detector, it is possible to obtain output signals having the linearity reaching mV order, and to shorten its pulse width to approximately 600 ps.
    Type: Application
    Filed: October 28, 2009
    Publication date: April 28, 2011
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Motohiro SUYAMA, Takayuki Ohmura, Hiroshi Kobayashi
  • Patent number: 7928657
    Abstract: The present invention relates to a photomultiplier having a fine configuration capable of realizing stable detection accuracy. The photomultiplier has a housing whose inside is maintained vacuum, and a photocathode, an electron-multiplier section, and an anode are disposed in the housing. In particular, one or more control electrodes disposed in an internal space of the housing which surrounds the electron-multiplier section and the anode are electrically connected via one or more connection parts extending from an electron emission terminal of the electron-multiplier section.
    Type: Grant
    Filed: June 1, 2006
    Date of Patent: April 19, 2011
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hiroyuki Kyushima, Hideki Shimoi, Hiroyuki Sugiyama, Hitoshi Kishita, Suenori Kimura, Yuji Masuda, Takayuki Ohmura
  • Patent number: 7923929
    Abstract: The present invention relates to a photomultiplier having a structure that enables to perform high gain and satisfy higher required characteristics. In the photomultiplier, an electron-multiplying unit accommodated in a sealed container comprises a focusing electrode, an accelerating electrode, a dynode unit, and an anode. Particularly, at least the accelerating electrode and dynode unit are held unitedly in a state that at least a first-stage dynode and a second-stage included in the dynode unit are opposite directly to the accelerating electrode not through a conductive material. A conventional metal disk for supporting directly dynodes which are set to the same potential as that of the first-stage dynode is not placed between the accelerating electrode and dynode unit; thus, variations of the transit time of electrons may be drastically reduced while the electrons reach from the cathode to the second-stage dynode via the first-stage dynode.
    Type: Grant
    Filed: May 7, 2008
    Date of Patent: April 12, 2011
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Takayuki Ohmura, Suenori Kimura, Masuo Ito
  • Patent number: 7919921
    Abstract: The present invention relates to a photomultiplier having a fine structure capable of realizing high multiplication efficiency. The photomultiplier comprises a housing whose inside is maintained vacuum, and, on a device mounting surface which is a part of an inner wall surface defining an internal space of the housing, a photocathode serving as a reflection type photocathode, an electron-multiplier section, an anode, and a voltage distributing section are disposed integrally. In particular, the electron-multiplier section is constituted by dynodes at multiple stages cascade-multiplying photoelectrons from the photocathode, and the voltage distributing section, which applies corresponding voltages to the dynodes at the respective stages respectively, is on the same surface together with the electron-multiplier section.
    Type: Grant
    Filed: June 1, 2006
    Date of Patent: April 5, 2011
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hiroyuki Kyushima, Hideki Shimoi, Hiroyuki Sugiyama, Hitoshi Kishita, Suenori Kimura, Yuji Masuda, Takayuki Ohmura
  • Patent number: 7880385
    Abstract: The present invention relates to a photomultiplier having a fine structure capable of realizing high detection accuracy by effectively suppressing cross talk among electron-multiplier channels. The photomultiplier comprises a housing whose inside is maintained vacuum, and, in the housing, a photocathode, an electron-multiplier section, and anodes are disposed. The electron-multiplier section has groove portions for cascade-multiplying photoelectrons as electron-multiplier channels, and the anodes are constituted by channel electrodes corresponding to the groove portions respectively defined by wall parts. In particular, at least parts of the respective channel electrodes are located in spaces sandwiched between pairs of wall parts defining the corresponding groove portions.
    Type: Grant
    Filed: June 1, 2006
    Date of Patent: February 1, 2011
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hiroyuki Kyushima, Hideki Shimoi, Hiroyuki Sugiyama, Hitoshi Kishita, Suenori Kimura, Yuji Masuda, Takayuki Ohmura
  • Patent number: 7855510
    Abstract: A photomultiplier tube includes: a cathode, a plurality of dynodes, and an electron lens forming electrode. The cathode emits electrons in response to incident light. The plurality of dynodes multiplies electrons emitted from the cathode. The electron lens forming the electrode is disposed in a prescribed position in relation to an edge of a first dynode positioned in a first stage from the cathode and an edge of a second dynode positioned in a second stage from the cathode, and smoothes an equipotential surface in a space between the first dynode and the second dynode along a longitudinal direction of the first dynode. This structure improves time resolution in response to incident light.
    Type: Grant
    Filed: December 24, 2004
    Date of Patent: December 21, 2010
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Takayuki Ohmura, Suenori Kimura, Masuo Ito
  • Patent number: 7821203
    Abstract: The present invention relates to a photomultiplier that realizes significant improvement of response time properties with a structure enabling mass production. The photomultiplier comprises a sealed container, and the sealed container includes a hollow body section, extending along a tube axis, and a faceplate. The faceplate has a light incidence surface and a light emission surface on which a photocathode is formed. In particular, the light emission surface is constituted by a flat region, and a curved-surface processed region that is positioned at a periphery of the flat region and that includes edges of the light emission surface. A surface shape of the peripheral region of the light emission surface of the faceplate is thus intentionally changed in order to adjust the angles of emission of photoelectrons from the photocathode positioned at the peripheral region.
    Type: Grant
    Filed: November 8, 2006
    Date of Patent: October 26, 2010
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Takayuki Ohmura, Suenori Kimura, Masuo Ito, Teruhiko Yamaguchi
  • Patent number: 7659666
    Abstract: The present invention relates to a photomultiplier that realizes significant improvement of response time properties with a structure enabling mass production. The photomultiplier comprises a sealed container, and, in the sealed container, a photocathode, at least one dynode set, a dynode unit including a part of insulating supporting members holding the one dynode unit, and a gain control unit are housed. The gain control unit has an insulating base plate, and the insulating base plate is integrally fixed with a control dynode and a final stage dynode that belong to each dynode set together with an anode. By the insulating base plate thus being clamped by the pair of insulating supporting members, the anode, the control dynode, and the final stage dynode constitute a part of an electron multiplier section.
    Type: Grant
    Filed: November 8, 2006
    Date of Patent: February 9, 2010
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Takayuki Ohmura, Teruhiko Yamaguchi
  • Publication number: 20090224666
    Abstract: The present invention relates to a photomultiplier having a fine structure capable of realizing high multiplication efficiency. The photomultiplier comprises a housing whose inside is maintained vacuum, and, on a device mounting surface which is a part of an inner wall surface defining an internal space of the housing, a photocathode serving as a reflection type photocathode, an electron-multiplier section, an anode, and a voltage distributing section are disposed integrally. In particular, the electron-multiplier section is constituted by dynodes at multiple stages cascade-multiplying photoelectrons from the photocathode, and the voltage distributing section, which applies corresponding voltages to the dynodes at the respective stages respectively, is on the same surface together with the electron-multiplier section.
    Type: Application
    Filed: June 1, 2006
    Publication date: September 10, 2009
    Inventors: Hiroyuki Kyushima, Hideki Shimoi, Hiroyuki Sugiyama, Hitoshi Kishita, Suenori Kimura, Yuji Masuda, Takayuki Ohmura
  • Publication number: 20090218944
    Abstract: The present invention relates to a photomultiplier having a fine configuration capable of realizing stable detection accuracy. The photomultiplier has a housing whose inside is maintained vacuum, and a photocathode, an electron-multiplier section, and an anode are disposed in the housing. In particular, one or more control electrodes disposed in an internal space of the housing which surrounds the electron-multiplier section and the anode are electrically connected via one or more connection parts extending from an electron emission terminal of the electron-multiplier section.
    Type: Application
    Filed: June 1, 2006
    Publication date: September 3, 2009
    Inventors: Hiroyuki Kyushima, Hideki Shimoi, Hiroyuki Sugiyama, Hitosha Kishita, Suenori Kimura, Yuji Masuda, Takayuki Ohmura
  • Publication number: 20090212699
    Abstract: The present invention relates to a photomultiplier that realizes a significant improvement of response time characteristics by a structure enabling mass production. The photomultiplier comprises a sealed container, and, in the sealed container, a photocathode, an electron multiplier section, and an anode are respectively disposed. The electron multiplier section includes multiple stages of dynode units, and each of the multiple stages of dynode units is fixed with one end of the associated dynode pin while being electrically connected thereto. In particular, the dynode pin, whose one ends are fixed to the multiple stages of dynode units, are held within an effective region of the electron multiplier section contributing to secondary electron multiplication, when the electron multiplier section is viewed from the photocathode side.
    Type: Application
    Filed: February 19, 2009
    Publication date: August 27, 2009
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Takayuki Ohmura, Hiroyuki Kyushima, Hideki Shimoi, Tsuyoshi Kodama
  • Publication number: 20090045741
    Abstract: The present invention relates to a photomultiplier having a fine structure capable of realizing high detection accuracy by effectively suppressing cross talk among electron-multiplier channels. The photomultiplier comprises a housing whose inside is maintained vacuum, and, in the housing, a photocathode, an electron-multiplier section, and anodes are disposed. The electron-multiplier section has groove portions for cascade-multiplying photoelectrons as electron-multiplier channels, and the anodes are constituted by channel electrodes corresponding to the groove portions respectively defined by wall parts. In particular, at least parts of the respective channel electrodes are located in spaces sandwiched between pairs of wall parts defining the corresponding groove portions.
    Type: Application
    Filed: June 1, 2006
    Publication date: February 19, 2009
    Inventors: Hiroyuki Kyushima, Hideki Shimoi, Hiroyuki Sugiyama, Hitoshi Kishita, Suenori Kimura, Yuji Masuda, Takayuki Ohmura