Patents by Inventor Yasuharu Hirai

Yasuharu Hirai 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: 7499520
    Abstract: A sample which includes a region exhibiting a large density change, such as, bones or lungs and a region exhibiting a small density change, such as, biological soft tissues, and whose measurement is difficult to do for conventional absorption and phase contrast X-ray imaging apparatuses is highly sensitively imaged and observed. In a phase contrast X-ray imaging apparatus using an X-ray interferometer, a reference object whose shape and internal density distribution are analogous to those of a sample and which is known is positioned on an optical path other than an optical path in the interferometer on which the sample is positioned.
    Type: Grant
    Filed: May 9, 2007
    Date of Patent: March 3, 2009
    Assignee: Hitachi, Ltd.
    Inventors: Akio Yoneyama, Yasuharu Hirai
  • Patent number: 7346145
    Abstract: To obtain an image that uses both an accurate spatial differential of an object-caused phase shift and the phase shift as contrast at a small observation field of view and under a simplified apparatus configuration , , , . a spatial differential of the object-caused phase shift and the phase shift are arithmetically obtained from the diffraction images of the object formed by simultaneous X-ray diffraction of crystals.
    Type: Grant
    Filed: January 27, 2006
    Date of Patent: March 18, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Akio Yoneyama, Yasuharu Hirai
  • Publication number: 20080019482
    Abstract: A sample which includes a region exhibiting a large density change, such as, bones or lungs and a region exhibiting a small density change, such as, biological soft tissues, and whose measurement is difficult to do for conventional absorption and phase contrast X-ray imaging apparatuses is highly sensitively imaged and observed. In a phase contrast X-ray imaging apparatus using an X-ray interferometer, a reference object whose shape and internal density distribution are analogous to those of a sample and which is known is positioned on an optical path other than an optical path in the interferometer on which the sample is positioned.
    Type: Application
    Filed: May 9, 2007
    Publication date: January 24, 2008
    Inventors: Akio Yoneyama, Yasuharu Hirai
  • Publication number: 20060256918
    Abstract: To obtain an image that uses both an accurate spatial differential of an object-caused phase shift and the phase shift as contrast at a small observation field of view and under a simplified apparatus configuration. a spatial differential of the object-caused phase shift and the phase shift are arithmetically obtained from the diffraction images of the object formed by simultaneous X-ray diffraction of crystals.
    Type: Application
    Filed: January 27, 2006
    Publication date: November 16, 2006
    Inventors: Akio Yoneyama, Yasuharu Hirai
  • Patent number: 4704540
    Abstract: A shock wave detection system used in a vacuum protection system constructed so that a high-speed shutter provided in a vacuum pipe connecting a vacuum system with an experimental apparatus is closed in response to the detection of an atmospheric shock wave that will rush into the vacuum system when an accidental vacuum breakdown occurs at the experimental apparatus.
    Type: Grant
    Filed: June 9, 1986
    Date of Patent: November 3, 1987
    Assignee: Hitachi, Ltd.
    Inventor: Yasuharu Hirai
  • Patent number: 4379250
    Abstract: A field emission cathode of the present invention is characterized by the possession of a special layer which is adsorbed onto the surfaces of a tip that is joined to the top of a hairpin-shaped filament.This layer is formed by adsorbing a selected metal via oxygen to a thickness which does not exceed the thickness of the monolayer of atoms.The metal will be selected from chromium, aluminum, cerium, magnesium, titanium, silicon, zirconium or hafnium.The field emission cathode features that the electrons are emitted in a concentrated manner from a particular crystal plane among the crystal planes of the tip.Therefore, it is possible to obtain a field emission cathode having very small emission angle of electrons.
    Type: Grant
    Filed: October 17, 1980
    Date of Patent: April 5, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Shigeyuki Hosoki, Shigehiko Yamamoto, Hideo Todokoro, Susumu Kawase, Yasuharu Hirai