Patents by Inventor Kimitsugu Nakamura

Kimitsugu Nakamura 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: 5598061
    Abstract: A photomultiplier includes a photoelectric surface for photoelectrically converting incident light and emitting electrons, and a plurality of stages of dynodes for multiplying the electrons. The photomultiplier includes a first dynode array including box-and-grid dynodes arranged in a vessel and a second dynode array including in-line dynodes arranged in the vessel. A dynode having a curved secondary electron emitting layer opposes both a secondary electron emitting layer of a last stage dynode of the first dynode array and a secondary electron emitting layer of a first-stage dynode of the second dynode array.
    Type: Grant
    Filed: March 7, 1995
    Date of Patent: January 28, 1997
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Kimitsugu Nakamura, Yoshio Fujita, Keiichi Ohishi
  • Patent number: 5561347
    Abstract: There is provided a photomultiplier in which a transmittance of an incident light and a photosensitivity is high and a hysteresis characteristic is excellent. Therefore, in the present invention, a photocathode 16, dynodes 17a to 17c and an anode 18 are supported between insulating material substrates 12a and 12b provided in a glass bulb 11. A transparent conductive film 19 is formed on an inside wall surface of a light entrance portion 15. The transparent conductive film 19 electrically contacts with a pad 20 which is led through a terminal 14 to the outside. The same potential as the photocathode 12 is applied through the pad 20 to the transparent conductive film 19. The incident light directly impinges on the photocathode 16 through the glass bulb 11 and the transparent conductive film 19 at a place corresponding to the light entrance portion 15. As a result, the incident light reaches the photocathode 12 with not being interfered at all, and the transmittance of the incident light is improved.
    Type: Grant
    Filed: October 5, 1994
    Date of Patent: October 1, 1996
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Kimitsugu Nakamura, Hiroyuki Hanai, Takeo Hashimoto, Shinji Suzuki, Yasushi Watase, Masumi Tachino
  • Patent number: 5420476
    Abstract: An electron lens electrode for guiding photoelectrons emitted from a photocathode to an electron multiplier section is arranged between the photocathode and the light-incident portion of a sealed container, and an opening is formed at a portion of the electron lens electrode opposing the light-incident portion. Incident light reaches the photocathode through the opening without being scattered or absorbed at all. The transmittance of light incident on a photomultiplier is improved, and the output waveform is uniformed, resulting in an improved S/N ratio.
    Type: Grant
    Filed: May 27, 1993
    Date of Patent: May 30, 1995
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Kimitsugu Nakamura, Takeo Hashimoto, Hiroaki Washiyama, Tomihiko Kuroyanagi
  • Patent number: 5363014
    Abstract: A photomultiplier for receiving incident light on a photocathode, and cascade-multiplying electrodes emitted from the photocathode by a secondary electronic effect of a plurality of dynodes, whereby the incident light is detected. The photomultiplier includes a slowing-down electrode for decelerating those of secondary electrons emitted from a dynode on the first stage to a dynode on the second stage which have a higher speed. Because of the slowing-down electrode the secondary electrons having a higher speed are selectively decelerated, whereby a transit time spread of the secondary electrons emitted from parts of the first stage-dynode to the second stage-dynode is relatively decreased.
    Type: Grant
    Filed: October 23, 1992
    Date of Patent: November 8, 1994
    Assignee: Hamamatsu Photonics K.K.
    Inventor: Kimitsugu Nakamura
  • Patent number: 5336902
    Abstract: This invention relates to a semiconductor photo-electron-emitting device for emitting photoelectrons excited from the valence band to the conduction band by incident photons on a semiconductor layer. The device includes a Schottky electrode formed on the emitting surface on a surface of the semiconductor layer, and a conductor layer formed on a surface opposite to the emitting surface. A set bias voltage is applied between the Schottky electrode and the conductor layer to accelerate photoelectrons generated by the excitation of incident photons to the emitting surface and to transfer the accelerated photoelectrons from an energy band of a smaller effective mass to an energy band of a larger effective mass.
    Type: Grant
    Filed: October 5, 1992
    Date of Patent: August 9, 1994
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Minoru Nigaki, Tuneo Ihara, Toru Hirohata, Tomoko Suzuki, Kimitsugu Nakamura, Norio Asakura, Masami Yamada, Yasuharu Negi, Tomihiko Kuroyanagi, Yoshihiko Mizushima
  • Patent number: 5210403
    Abstract: There is disclosed a phototube comprising a closed container having a light permeable face plate the outside surface of which is a light incident surface, a photocathode so provided in the closed container that at least a part of a photo-electric surface is inclined to the light incident surface, and an anode so provided in the closed container that an electron capturing surface is opposed to the photo-electric surface in parallelism therewith.
    Type: Grant
    Filed: May 22, 1992
    Date of Patent: May 11, 1993
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Kimitsugu Nakamura, Masuo Ito, Seiji Suzuki, Yasushi Watase
  • Patent number: 4950951
    Abstract: A secondary electron multiplier having a Venetian blind dynode structure for use in a photomultiplier tube or the like. The dynode structure includes first and second dynodes being vertically disposed transverse to each other in that the geometrically transparent part of the first dynode is aligned with a portion of the geometrically opaque part of the second dynode corresponding to a width dimension defined from the lower end of the second dynode, and the voltages applied to the dynodes are specially configured to provide a sufficient energy to the dynodes for secondary electron mulitplication.
    Type: Grant
    Filed: January 24, 1989
    Date of Patent: August 21, 1990
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Kazuyoshi Okano, Kimitsugu Nakamura, Hiroyuki Kyushima
  • Patent number: 4881008
    Abstract: A photomultiplier with plural photocathodes comprising a rectangular end face plate, plural photocathodes arranged on the end face plates at predetermined intervals in the longitudinal direction of the end face plate, plural focusing electrodes assigned to the photocathodes respectively, plural dynodes provided in common for all of the photocathodes, and plural anode electrodes assigned to the photocathodes respectively, each of the dynodes having plural electron emitting parts for emitting secondary electrons and insulating parts for preventing the secondary electrons emitted from any one of the electron emitting parts from straying into the other electron emitting parts.
    Type: Grant
    Filed: April 18, 1988
    Date of Patent: November 14, 1989
    Assignees: Hamamatsu Photonics Kabushiki Kaisha, Research Development Corporation of Japan
    Inventors: Hiroyuki Kyushima, Kimitsugu Nakamura, Takahito Kato
  • Patent number: 4825066
    Abstract: A photomultiplier for converting an incident weak light into multiplied electrons to thereby output an electrical signal corresponding to the intensity of the incidence light. The photomultiplier comprises a photocathode for emitting primary electrons; plural dynodes for emitting secondary electrons in response to incident of the primary electrons and multiplying first secondary electrons passing between the dynodes; and shield means for preventing second secondary electrons emitted from a first dynode of the dynodes toward the photocathode from returning to the dynodes, thereby to reduce the generation of a residual pulse currents caused by the second secondary electrons and to accurately detect a main pulse current caused by the first secondary electrons.
    Type: Grant
    Filed: February 12, 1988
    Date of Patent: April 25, 1989
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Kimitsugu Nakamura, Masuo Ito