Patents by Inventor Shinichiro Aoshima

Shinichiro Aoshima 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: 5307199
    Abstract: The optical apparatus includes first and second deflection members, a mask, a pumping light source, and a controller. The first and second deflection members are formed of nonlinear optical material whose refractive index is changed upon light radiation. The mask is arranged on an optical path extending from a front side of the first deflection member to a rear side of a second deflection member. The mask has a predetermined transmission pattern. The pumping light source radiates first and second beams on predetermined regions of the first and second deflection members. This changes the refractive indices of the predetermined regions to bend the optical path. The controller variably controls the intensity of the first and second beams.
    Type: Grant
    Filed: July 25, 1991
    Date of Patent: April 26, 1994
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Tsuneyuki Urakami, Shinichiro Aoshima, Yutaka Tsuchiya
  • Patent number: 5289114
    Abstract: A light source for emitting a pulsed laser beam having an ultrashort pulse width and a voltage detector including the light source therein. The light source includes a laser driving unit for driving the laser source to output the pulsed laser beam while the intensity of the pulsed laser beam is stabilized. A chirp compensator is also included to compensate for a chirp in the pulsed laser beam. A wavelength selector is used to extract light having a desired wavelength from the pulsed laser beam, thereby obtaining a pulsed laser beam having an ultrashort pulse width and a desired narrow spectral band width.
    Type: Grant
    Filed: June 11, 1991
    Date of Patent: February 22, 1994
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Takuya Nakamura, Shinichiro Aoshima, Yutaka Tsuchiya
  • Patent number: 5237388
    Abstract: Young's interferometer consisting of a single slit and a double slit member, and an analyzer are arranged along the axis of light to be measured. Parallel slits of the double slit member are provided with respective polarizers whose paralyzing directions are at .+-.45.degree. to the longitudinal direction of the parallel slits. The polarizing direction of the analyzer is set in parallel with the parallel slits. The incident light passes through Young's interferometer and the analyzer to form an interference fringe, which is detected by an image detector unit. An image analyzer unit produces an intensity profile of the interference fringe and determines the polarization state of the incident light, for instance, by comparing the produced intensity profile with conceivable profiles stored in advance.
    Type: Grant
    Filed: September 19, 1991
    Date of Patent: August 17, 1993
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Isuke Hirano, Hironori Takahashi, Tsuneyuki Urakami, Tamiki Takemori, Yutaka Tsuchiya, Shinichiro Aoshima
  • Patent number: 5220579
    Abstract: A pulse laser has a laser resonator, a laser medium in the laser resonator, and a deflecting device. The laser medium emits an emission light. The deflecting device switches an optical path of the emission light to output the emission light as a laser pulse. The deflecting device includes a deflecting member and a pumping device. The deflecting member is arranged in the optical path of the emission light. The deflection member has a refractive index which changes based on a pumping light incident thereon. The pumping device radiates the pumping light on a predetermined region of the deflection member and varies the refractive index of the predetermined region to switch the optical path of the emission light.
    Type: Grant
    Filed: July 25, 1991
    Date of Patent: June 15, 1993
    Assignee: Hamamatsu Photonics, K.K.
    Inventors: Tsuneyuki Urakami, Shinichiro Aoshima
  • Patent number: 5198921
    Abstract: A semiconductor light amplifier is driven by a drive device, and selectively amplifies one of a TM mode component and a TE mode component of input light. For example, TE mode light is selectively amplified by making thickness of the active layer of the semiconductor light amplifier not more than 0.05 .mu.m, or by tilting at least one of the entrance and exit faces of the semiconductor light amplifier by 10 to 16 degrees. An another type of light amplifying polarizer, input signal light and excitation light are combined by a half mirror or an optical coupler, and combined light is input to a rare-earth-element doped, polarization maintaining optical fiber.
    Type: Grant
    Filed: November 21, 1991
    Date of Patent: March 30, 1993
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Shinichiro Aoshima, Tsuneyuki Urakami, Yutaka Tsuchiya
  • Patent number: 5179565
    Abstract: A low noise pulsed light source utilizing a laser diode for generating a short pulsed light of a high repetitive frequency. The low noise pulsed light source includes a laser diode drived by an electric pulse generator for emitting repetitive pulsed light; a current source for supplying a bias current to the laser diode; and a photodetector for detecting the repetitive pulsed light emitted from the laser diode; and control means. The control means modulates at least one of the bias current from the current source and the amplitude of a pulse signal generated from the electric pulse generator in accordance with an output signal from the photodetector such that the intensity of the pulsed light is kept unchanged and any noise involved in the same is reduce. A feedback system including the photodetector and the control means has a peak in its frequency characteristics within a frequency band for light detecting in a light measuring system utilizing the low noise pulsed light source.
    Type: Grant
    Filed: June 5, 1991
    Date of Patent: January 12, 1993
    Assignee: Hamamatsu Photonics, K.K.
    Inventors: Yutaka Tsuchiya, Shinichiro Aoshima, Hironori Takahashi, Takuya Nakamura
  • Patent number: 5164667
    Abstract: A voltage detecting device using an electro-optical material with a refractive index which is changed by a voltage at a part of an object comprising a light source, comprises an electro-optical material for changing the optical path of the light beam from the light source in accordance with the refraction index of the electro-optical material and a slit or optical fiber extractor at a predetermined position at the output of the electro-optical material for extracting the quantity of light of the light beam at the predetermined position and a detector detecting a voltage at the part of the object from the quantity of light extracted.
    Type: Grant
    Filed: November 30, 1990
    Date of Patent: November 17, 1992
    Assignee: Hamamatsu Photonics K. K.
    Inventors: Hironori Takahashi, Shinichiro Aoshima, Takuya Nakamura, Yutaka Tsuchiya
  • Patent number: 5153667
    Abstract: A light beam is chopped and split into two beams. Intensity of a first beam is changed by using, e.g., an electrooptic material in accordance of a change in a signal to be detected, such as a voltage in an electronic device, and detected by a first photodetector. On the other hand, a second beam is detected by a second photodetector without being subjected to the intensity change. At least one of the outputs of the first and second photodetectors are adjusted so that they become equal to each other when no signal is applied to the light intensity changing means. The difference of the thus adjusted output signals is detected by, e.g., a lock-in amplifier in a narrow band at the chopping frequency.
    Type: Grant
    Filed: November 26, 1990
    Date of Patent: October 6, 1992
    Assignee: Hamamatsu Photonics K. K.
    Inventors: Shinichiro Aoshima, Hironori Takahashi, Yutaka Tsuchiya
  • Patent number: 5121404
    Abstract: An optically pumped solid laser that uses a corner cube or rectangular prism as its solid laser medium, containing end faces through which a semiconductor pumping light beam is applied to the medium. The solid laser medium contains at least one kind of coating formed on at least a part of an end face, such that the end face acts as a resonator and/or output mirror. Optical fibers may be connected to the end faces for inputting or outputting light beams. Non-linear crystals in waveguide form may be coupled to the outputting end face of the medium, specifically crystals of either SHG, THG, FHG, or parameteric; and KTP, .beta.-BaB.sub.2 O.sub.4, KNbP.sub.3, or MgO doped LiNbO.sub.3.
    Type: Grant
    Filed: May 9, 1991
    Date of Patent: June 9, 1992
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Shinichiro Aoshima, Kenshi Fukumitsu
  • Patent number: 5119385
    Abstract: Light input means inputs exciting pulse light beams to a parametric oscillator simultaneously in a plurality of directions. The parametric oscillator including a parametric element such as a urea crystal produces parametric pulse beams having different wavelengths. The parametric pulse beams are corrected into coaxial beams by a correcting optical means which includes an optical fiber, and then group dispersion of the coaxial beams are compensated for by a group dispersion compensating means which includes opposed diffraction gratings.
    Type: Grant
    Filed: August 1, 1990
    Date of Patent: June 2, 1992
    Assignee: Hamamatsu Photonics K. K.
    Inventors: Shinichiro Aoshima, Hideo Suzuki
  • Patent number: 5082340
    Abstract: In a wavelength converting device including a light waveguide made of nonlinear optical material and outputting Cherenkov light, a reflecting mirror for reflecting guided light is provided at the end of the light waveguide. The light waveguide may include a light introducing portion and a curved light waveguide smoothly coupled with the light introducing portion. The light waveguide may have a Y-shaped structure including two light introducing portions partially parallel to each other, a junction part at which the two light introducing portions are smoothly joined together, and a linear light generating portion coupled with the junction part.
    Type: Grant
    Filed: April 27, 1990
    Date of Patent: January 21, 1992
    Assignee: Hamamatsu Photonics K. K.
    Inventors: Shinichiro Aoshima, Hironori Takahashi, Yutaka Tsuchiya
  • Patent number: 5077745
    Abstract: Part of a solid-state lasing medium is made to be a mode locking section. An ultrasonic transducer being supplied with a high-frequency voltage generates an ultrasonic wave to propagate through the mode locking section. As a result, laser light pulses having a repetition frequency determined by the frequency of the ultrasonic wave are output from a laser apparatus.
    Type: Grant
    Filed: April 6, 1990
    Date of Patent: December 31, 1991
    Assignee: Hamamatsu Photonics K. K.
    Inventors: Shinichiro Aoshima, Kenshi Fukumitsu
  • Patent number: 5055770
    Abstract: A voltage in a selected area of an object is measured by launching an input light beam into an electrooptic material whose refractive index is changed in accordance with an electric field created by the voltage in a selected area of an object to be measured, and detecting a change in polarization or in a deflection angle of an output light beam from the electrooptic material. A medium having a dielectric constant greater than the air is placed between the area to be measured and the electrooptic material.
    Type: Grant
    Filed: April 11, 1990
    Date of Patent: October 8, 1991
    Assignee: Hamamatsu Photonics K. K.
    Inventors: Hironori Takahashi, Shinichiro Aoshima, Yutaka Tsuchiya
  • Patent number: 5043568
    Abstract: A first part of input light containing both background light and signal light is extracted by a sampling streak tube and converted to a first electric signal by a photodetector. A second part of the input light containing only background light is extracted by the same sampling streak tube by offsetting the sampling timing and converted to a second electric signal by the photodetector. A signal component corresponding to the signal light is extracted by taking the difference between the first and second electric signals. In one embodiment, the sampling timing is offset by applying a chopping voltage to chopping electrodes provided in the sampling streak tube.
    Type: Grant
    Filed: April 10, 1990
    Date of Patent: August 27, 1991
    Assignee: Hamamatsu Photonics K. K.
    Inventors: Yutaka Tsuchiya, Shinichiro Aoshima, Hironori Takahashi, Takuya Nakamura
  • Patent number: 5034683
    Abstract: A voltage detecting device for detecting voltages in an object under test including an electro-optic material covering a plurality of parts of the object under test; the refractive index of the electro-optic material being variable according to an applied voltage. A light source emits light through the electro-optic material toward the object under test and a detecting device receives an emergent light beam reflected from within the electro-optic material in order to detect voltages in the object. Further, a scanning device automatically scans the object under test with the light beam in order to detect voltages at a plurality of locations on the object.
    Type: Grant
    Filed: January 3, 1990
    Date of Patent: July 23, 1991
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hironori Takahashi, Shinichiro Aoshima, Yutaka Tsuchiya
  • 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: 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: 4982152
    Abstract: A voltage detecting device using an electro-optical material with a refractive index which is changed by a voltage at a part of an object comprising a light source, comprises an electro-optical material for changing the optical path of the light beam from the light source in accordance with the refraction index of the electro-optical material and a slit or optical fiber extractor at a predetermined position at the output of the electro-optical material for extracting the quantity of light of the light beam at the predetermined position and a detector detecting a voltage at the part of the object from the quantity of light extracted.
    Type: Grant
    Filed: June 2, 1988
    Date of Patent: January 1, 1991
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hironori Takahashi, Shinichiro Aoshima, Takuya Nakamura, Yutaka Tsuchiya