Patents Assigned to Hamamatsu Photonics Kabushiki Kaisha
  • Patent number: 5048942
    Abstract: In order to reduce the light reflectance, an optical element comprises an optical element body formed of an optical crystal or a lens, and glass members with a prescribed refractive index, wherein the glass member is bonded to each of the light incident and emergent surfaces of the element body by an adhesive agent with a prescribed refractive index. The optical element body will not be affected adversely even if it is made of a crystal which is vulnerable to heat.
    Type: Grant
    Filed: October 17, 1988
    Date of Patent: September 17, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventor: Yasushi Ohbayashi
  • Patent number: 5034921
    Abstract: An optical memory circuit comprises two photodetectors, and an intermediate signal conductor for connecting the two photodetectors, wherein the two photodetectors and the signal conductor are connected in series in a closed circuit, wherein each of the photodetectors comprises two spaced Schottky electrodes symmetrically disposed on a semiconductor substrate and the signal conductor has a capacitance with a time constant of a potential of the signal conductor such that charges are stored in the signal conductor when an optical write signal is incident on one photodetector and stored charges are released from the signal conductor when an optical read signal is incident on the other photodetector.
    Type: Grant
    Filed: July 6, 1989
    Date of Patent: July 23, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Kazutoshi Nakajima, Hirofumi Kan, Kenichi Sugimoto, Yoshihiko Mizushima, Toru Hirohata, Takashi Iida, Yoshihisa Warashina, Toru Hirohata, Takashi Iida
  • Patent number: 5032024
    Abstract: An optical examination apparatus for optically examining density, distribution, etc.
    Type: Grant
    Filed: May 1, 1989
    Date of Patent: July 16, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventor: Mark Cope
  • Patent number: 5029221
    Abstract: An image reconstructing apparatus wherein the object under examination is irradiated in at least one direction to provide projection data, and the provided projection data is optically processed to form a reconstructed image representing the internal information of the object. An image associated with the projection data is formed and stored in the storage medium. The stored image is optically read out of the storage medium. The read out stored image which corresponds to one direction of irradiation is integrated at a time to produce sum data. The sum data and projection data corresponding to the same direction of irradiation are compared to form correction data. An image associated with the correction data is formed and optically superposed on the stored image in the storage medium corresponding to the same direction of irradiation, to produce the reconstructed image.
    Type: Grant
    Filed: January 10, 1989
    Date of Patent: July 2, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Yoshihiro Takiguchi, Makoto Kato
  • Patent number: 5025142
    Abstract: A light waveform shaping apparatus comprises; a beam splitting means for branching an input optical signal into two optical signals; a photoelectric converter for converting one of the two branched optical signals into an electrical signal; an optical amplifier whose gain is adjustable by a controlling electrical signal, for amplifying an optical signal; an input optical path for introducing the other branched optical signal to the optical amplifier; and an electrical circuit for introducing the electrical signal from the photoelectric converter to the optical amplifier; wherein the optical and controlling electrical signals are supplied to the optical amplifier at a predetermined timing of generally coincident arrival.
    Type: Grant
    Filed: May 19, 1989
    Date of Patent: June 18, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Shinichiro Aoshima, Tsuneyuki Urakami, Yutaka Tsuchiya
  • Patent number: 5020064
    Abstract: An electromagnetic wave device having an amplification function comprises a medium containing free carriers, means for applying a magnetic field to the medium, means for applying an input electromagnetic wave to the medium in a direction perpendicular to the magnetic field, and means for generating an electric field to accelerating the carriers in the direction of the input electromagnetic wave. A frequency of the input electromagnetic wave is within the range of the plasma frequency plus or minus the cyclotron frequency, and a polarization direction of the input electromagnetic wave is perpendicular both to the magnetic field and its own traveling direction. Furthermore, the device has such functions as oscillation, modulation, frequency conversion, etc. depending on the type of added units.
    Type: Grant
    Filed: August 14, 1989
    Date of Patent: May 28, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Yoshihiko Mizushima, Takashi Iida, Toru Hirohata, Kenichi Sugimoto, Yoshihisa Warashina, Kazutoshi Nakajima
  • Patent number: 5017829
    Abstract: A framing camera comprises a photocathode, a first deflection means for scanning electron beams emitted from the photocathode, a slit plate having a single slit for converting the electron beams with a spatial picture image information into electron beams with a picture image of temporal sequence and a second deflection means for scanning the electron beams passed from the slit plate to have them impinge upon a phosphor screeen to thereby produce a plurality of framed patterns, in which deflection voltages supplied to the first and second deflection means are adjustable independently of each other.
    Type: Grant
    Filed: February 24, 1989
    Date of Patent: May 21, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Musubu Koishi, Motoyuki Watanabe
  • Patent number: 5012103
    Abstract: A radiation detector basically comprises a scintillator, a light guide for introducing scintillation light, and a photodetector for detecting the scintillation light. A light output portion of the scintillator is wedge-shaped, and a light input portion of the light guide is V-shaped in section so as to receive the wedge-shaped light output portion of the scintillator. With this arrangement, light reflection at the interfaces of the scintillator and light guide is reduced, resulting in an improvement of transmission efficiency of light.
    Type: Grant
    Filed: October 6, 1989
    Date of Patent: April 30, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Eiichi Tanaka, Hiroshi Uchida
  • Patent number: 5003268
    Abstract: An optical signal sampling apparatus for high-speed gating of an optical signal in the form of repetitive waveforms comprises an input optical path for introducing the optical signal to an optical amplifier; the optical amplifier whose gain is adjustable by a gating electrical signal, for amplifying the optical signal; a driving circuit for providing, in response to a sampling signal, the optical amplifier with the gating electrical signal having a series of pulses which are gradually shifted on a time axis with respect to the repetitive waveforms of the optical signal; and an output optical path for introducing an output optical signal from the optical amplifier.
    Type: Grant
    Filed: April 25, 1989
    Date of Patent: March 26, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventor: Yutaka Tsuchiya
  • Patent number: 5003474
    Abstract: A method and an apparatus for performing address transformation of projection data for use in a positron CT system, where plural detectors are classified into plural detector groups. In this system, a polar coordinate of the addresses assigned to paired detectors which detect coincident events of gamma-ray emission is determined by adding a first encoded signal representing a first polar coordinate of the line joining the reference points of the paired detector groups including the paired detectors and a second encoded signal representing a second polar coordinate of the deviation of the line joining the two detectors from the line joining the reference points. The second encoded signal is obtained on the basis of address signals representing the addresses of the two detectors and a third encoded signal representing the angle relationship of the paired detector groups which is preliminarily stored in a memory.
    Type: Grant
    Filed: April 21, 1989
    Date of Patent: March 26, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Takaji Yamashita, Keiji Shimizu
  • Patent number: 4996475
    Abstract: A voltage detector detects a voltage developing in a selected area of an object such as an integrated circuit by utilizing an electro-optic material equipped in an optical probe. A change in refractive index of the electro-optic material which is caused by the voltage in the object, is detected as a change of polarization of a light beam passing through the electro-optic material. In order to accomplish precise detection of the voltage, a mirror in the form of a thin metal film or a multilayered dielectric film is disposed at the tip of electro-optic material and, at the same time, a transparent electrode is disposed on the side of electro-optic material opposite to the side where the mirror is disposed. As a result, lines of electric force produced by the voltage developing in the object are aligned in the electro-optic material parallel to the center line of the optical probe and the change in refractive index becomes uniform.
    Type: Grant
    Filed: May 31, 1988
    Date of Patent: February 26, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Hironori Takahashi, Shinichiro Aoshima, Yutaka Tsuchiya
  • Patent number: 4994663
    Abstract: An apparatus for measuring an autocorrelation wavaeform of intensity of input light comprises a beam splitting means for dividing the input light into two light beams, a photoelectric converter for converting one of the divided beams into an electrical signal, an optical modulating means for modulating the other light beam in accordance with the electrical signal, a delay means for varying a relative delay time between arrival times to the optical modulating means of the light beam and the electrical signal, and a photodetector having a response speed faster than that of the delay time variation for detecting output light from the optical modulating means.
    Type: Grant
    Filed: May 23, 1989
    Date of Patent: February 19, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Shinichiro Aoshima, Tsuneyuki Urakami, Yutaka Tsuchiya
  • Patent number: 4988859
    Abstract: An optical waveform measuring device, comprising an optical amplifier for amplifying a light beam under measurement and a photodetector to which a light beam amplified by the optical amplifier is applied.
    Type: Grant
    Filed: May 11, 1989
    Date of Patent: January 29, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Yutaka Tsuchiya, Shinichiro Aoshima
  • Patent number: 4982151
    Abstract: A voltage measuring apparatus comprises an optical probe furnished with an electro-optic material whose refractive index is changed in accordance with a voltage developing in a given part of an object and an auxiliary electrode for terminating electric lines of force coming from the given part, a light source for producing light to be inputted to the electro-optic material, a light polarization detector for detecting a polarization state of output light from the electro-optic material, and a power source for applying a variable voltage to the auxiliary electrode. An absolute value of the voltage in the given part can be determined as a specific value of the variable voltage obtained when no change is detected in the polarization state of the output light.
    Type: Grant
    Filed: August 8, 1989
    Date of Patent: January 1, 1991
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Hironori Takahashi, Shinichiro Aoshima, Yutaka Tsuchiya
  • Patent number: 4980632
    Abstract: The electrical signal observing device measures the electrical signal by applying the electrical signal to be measured to an optical amplifier in order to modulate a short pulse light train directed through the electrical amplifier. The electrical signal to be measured acts as a gain control for the optical amplifier. The photodetector detects the output of the optical amplifier and applies a resultant electrical signal to an integrator circuit after which the signal is displayed. The signal may be displayed in a time base fashion using a sweep generated by a delay system of the short pulse light train.
    Type: Grant
    Filed: May 30, 1989
    Date of Patent: December 25, 1990
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Shinichiro Aoshima, Tsuneyuki Urakami, Yutaka Tsuchiya
  • Patent number: 4980772
    Abstract: An image intensifier tube and a solid-state image pickup device are combined to form a unified image pickup device. A thin fiber plate with thickness of 0.5-1.5 mm is interposed between a phosphor layer of the image intensifier tube and a photosensitive layer of the solid-state image pickup device. A microchannel plate may be incorporated to multiply photoelectrons emitted from a photocathode.
    Type: Grant
    Filed: May 17, 1989
    Date of Patent: December 25, 1990
    Assignees: Hamamatsu Photonics Kabushiki Kaisha, Nippon Hoso Kyokai
    Inventors: Tatsuro Kawamura, Humihiko Ando, Masayuki Sugawara, Takashi Ando, Masumi Tachino, Yasushi Watase, Toshio Ikuma, Kazumasa Kato
  • Patent number: 4974090
    Abstract: An image intensifier tube and a solid-state image pickup device are combined to form a unified image pickup device. A thin transparent glass layer polished to a thickness of 50 microns or less is interposed between a phosphor layer of the image intensifier tube and a photosensitive layer of the solid-state image pickup device. A microchannel plate may be incorporated to multiply photoelectrons emitted from a photocathode.
    Type: Grant
    Filed: May 17, 1989
    Date of Patent: November 27, 1990
    Assignees: Hamamatsu Photonics Kabushiki Kaisha, Nippon Hoso Kyokai
    Inventors: Tatsuro Kawamura, Humihiko Ando, Masayuki Sugawara, Takashi Ando, Masumi Tachino, Yasushi Watase, Toshio Ikuma, Kazumasa Kato
  • Patent number: 4968881
    Abstract: A voltage detector comprises a light modulator which employs an electro-optic material whose refractive index changes according to the voltage developing in an object to be measured. A transparent anti-reflection film having a refractive index and thickness which are predetermined on the bases of a refractive index of the electro-optic material and a wavelength of incident light is formed on both light entrance and exit surfaces of the electro-optic material.
    Type: Grant
    Filed: February 2, 1989
    Date of Patent: November 6, 1990
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Hironori Takahashi, Shinichiro Aoshima, Yoshiharu Ooi, Mutsuji Takahashi, Yutaka Tsuchiya
  • Patent number: 4967093
    Abstract: In a deformation measuring method and device in which an object is irradiated with a laser beam before and after deformation of the object to obtain speckle patterns, the speckle patterns thus obtained are photoelectrically converted into electrical signals, and the cross-correlation function between the speckle patterns is calculated using the electrical signals to obtain displacement of the speckle pattern on the basis of the shift of position of the extreme value of the mutual-correlation function and to determine the amount of deformation of the object from the displacement of the speckle pattern, (1) the reference speckle pattern data for calculation of the cross-correlation function is renewed when the extreme value of the cross-correlation function is lower in level than a predetermined value or when the position of the extreme value is out of a predetermined range, or (2) the reference speckle pattern data is renewed when the extreme value of the cross-correlation function is lower in level than a pre
    Type: Grant
    Filed: June 19, 1989
    Date of Patent: October 30, 1990
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventor: Tamiki Takemori
  • Patent number: 4967080
    Abstract: An apparatus for measuring the temporal correlation of fundamental particles such as photons, neutrons, X-rays or the like, comprising at least one deflector for sweeping the fundamental particles or images thereof in at least one direction, an aperture member having at least two apertures for time-divisionally extracting the swept fundamental particles or the images thereof, multiplication means, such as dynode groups or photomultipliers, for multiplying each of the extracted fundamental particles or the images thereof and a correlator for performing correlating arithmetic operations on the basis of each output signal from the multiplication means.
    Type: Grant
    Filed: September 19, 1988
    Date of Patent: October 30, 1990
    Assignee: Hamamatsu Photonics Kabushiki Kaisha
    Inventors: Tsuneyuki Urakami, Yoshihiro Takiguchi