Patents by Inventor Tetsu Tatsuma

Tetsu Tatsuma 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: 9871147
    Abstract: A photodetector including a substrate, a light absorption layer arranged over the substrate, the light absorption layer including a stack including a semiconductor layer that absorbs light of a wavelength having an electric field vector parallel to a normal direction of a substrate surface, a lower contact layer arranged on a first side of the light absorption layer, a lower electrode contacting with the lower contact layer, an upper contact layer arranged on a second side of the light absorption layer, and an upper electrode contacting with the upper contact layer. An uneven structure including polarization-selective shapes of projections or depressions on the second side of the upper contact layer is provided, the shapes of projections or depressions each having a size of a wavelength or less of incident light in the semiconductor layer and half the wavelength or greater and being periodically arranged in at least one direction.
    Type: Grant
    Filed: November 16, 2016
    Date of Patent: January 16, 2018
    Assignees: SHARP KABUSHIKI KAISHA, THE UNIVERSITY OF TOKYO
    Inventors: Teruhisa Kotani, Yasuhiko Arakawa, Tetsu Tatsuma
  • Publication number: 20170141243
    Abstract: A photodetector including a substrate, a light absorption layer arranged over the substrate, the light absorption layer including a stack including a semiconductor layer that absorbs light of a wavelength having an electric field vector parallel to a normal direction of a substrate surface, a lower contact layer arranged on a first side of the light absorption layer, a lower electrode contacting with the lower contact layer, an upper contact layer arranged on a second side of the light absorption layer, and an upper electrode contacting with the upper contact layer. An uneven structure including polarization-selective shapes of projections or depressions on the second side of the upper contact layer is provided, the shapes of projections or depressions each having a size of a wavelength or less of incident light in the semiconductor layer and half the wavelength or greater and being periodically arranged in at least one direction.
    Type: Application
    Filed: November 16, 2016
    Publication date: May 18, 2017
    Inventors: Teruhisa KOTANI, Yasuhiko ARAKAWA, Tetsu TATSUMA
  • Patent number: 9455054
    Abstract: The present invention relates to a radioactive cesium adsorbent, a method for producing the same, and a method for decontaminating the environment from radioactive cesium with the adsorbent. The radioactive cesium adsorbent of the present invention includes a hydrophilic fiber substrate supporting a Prussian blue analog, in particular, Prussian blue, and the Prussian blue analog is immobilized in the inside of the fibers.
    Type: Grant
    Filed: August 16, 2012
    Date of Patent: September 27, 2016
    Assignee: The Foundation for the Promotion of Industrial Science
    Inventors: Kazuyuki Ishii, Masashi Obi, Kazuaki Kudo, Kengo Akagawa, Tetsu Tatsuma, Akiyoshi Sakoda
  • Publication number: 20140194665
    Abstract: The present invention relates to a radioactive cesium adsorbent, a method for producing the same, and a method for decontaminating the environment from radioactive cesium with the adsorbent. The radioactive cesium adsorbent of the present invention includes a hydrophilic fiber substrate supporting a Prussian blue analogue, in particular, Prussian blue, and the Prussian blue analogue is immobilized in the inside of the fibers.
    Type: Application
    Filed: August 16, 2012
    Publication date: July 10, 2014
    Applicant: The Foundation for the Promotion of Industrial Science
    Inventors: Kazuyuki Ishii, Masashi Obi, Kazuaki Kudo, Kengo Akagawa, Tetsu Tatsuma, Akiyoshi Sakoda
  • Patent number: 6882459
    Abstract: The inventive photoreactive device has a semiconductor and an oxidation-reduction material. The semiconductor has a conduction band with a potential and being capable of producing electrons under the irradiation of light on the semiconductor. The oxidation-reduction material has a redox potential being positive compared with the potential of the conduction band. The semiconductor supplies electrons into the oxidation-reduction material to reduce it under the irradiation of light for storing the electrons. The stored electrons are discharged from the oxidation-reduction material into a metal material to prevent the corrosion of the metal material.
    Type: Grant
    Filed: August 28, 2001
    Date of Patent: April 19, 2005
    Assignees: Koyo Engineering
    Inventors: Akira Fujishima, Tetsu Tatsuma, Yoshihisa Ohko, Shuichi Saitoh, Katsuhisa Kashiwazaki
  • Patent number: 6544478
    Abstract: A QCM sensor including a sensor device, the sensor device having a crystal substrate, on both of front and rear surfaces of which a pair of electrodes are disposed so as to oppose with each other and the QCM sensor detecting and quantitatively analyzing components of a sample from either a variation in a fundamental resonant frequency or a variation in an impedance when a surface of one of the pair of electrodes is immersed into either a sample gas or a sample solution. The sensor device is arranged in a multi-channel structure such that four mutually opposing electrodes (11A through 14A, 12B through 14B) are disposed on both front and rear surfaces of the crystal substrate 10, each electrode being arranged to enable a fixation of a receptor which is different for each component of a sample to be detected and quantitatively analyzed, whereby the QCM sensor detects and quantitatively analyzes once the components of one sample different for different electrodes.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: April 8, 2003
    Assignees: Kabushiki Kaisha Meidensha
    Inventors: Noboru Oyama, Tetsu Tatsuma, Yoshihito Watanabe, Osamu Hatozaki, Kaoru Kitakizaki, Masanori Haba, Takayuki Noguchi
  • Publication number: 20020047134
    Abstract: The inventive photoreactive device has a semiconductor and an oxidation-reduction material. The semiconductor has a conduction band with a potential and being capable of producing electrons under the irradiation of light on the semiconductor. The oxidation-reduction material has a redox potential being positive compared with the potential of the conduction band. The semiconductor supplies electrons into the oxidation-reduction material to reduce it under the irradiation of light for storing the electrons. The stored electrons are discharged from the oxidation-reduction material into a metal material to prevent the corrosion of the metal material.
    Type: Application
    Filed: August 28, 2001
    Publication date: April 25, 2002
    Inventors: Akira Fujishima, Tetsu Tatsuma, Yoshihisa Ohko, Shuichi Saitoh, Katsuhisa Kashiwazaki