Patents by Inventor Tadao Katsuragawa

Tadao Katsuragawa 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: 8068387
    Abstract: A magneto-optical device is disclosed that includes a non-magnetic support body and a fine particle arrangement layer on the non-magnetic support body. The fine particle arrangement layer includes multiple regularly arranged fine metal magnetic particles. In the magneto-optical device, magnetization is generated by applying an external magnetic field to the fine metal magnetic particles, and linearly polarized light is made incident on the fine metal magnetic particles, so that a magneto-optical effect is increased by the interaction between the incident light on the fine metal magnetic particles and the surface plasmon oscillation of the fine metal magnetic particles.
    Type: Grant
    Filed: December 27, 2006
    Date of Patent: November 29, 2011
    Assignee: Ricoh Company, Ltd.
    Inventor: Tadao Katsuragawa
  • Publication number: 20090274016
    Abstract: A magneto-optical device is disclosed that includes a non-magnetic support body and a fine particle arrangement layer on the non-magnetic support body. The fine particle arrangement layer includes multiple regularly arranged fine metal magnetic particles. In the magneto-optical device, magnetization is generated by applying an external magnetic field to the fine metal magnetic particles, and linearly polarized light is made incident on the fine metal magnetic particles, so that a magneto-optical effect is increased by the interaction between the incident light on the fine metal magnetic particles and the surface plasmon oscillation of the fine metal magnetic particles.
    Type: Application
    Filed: December 27, 2006
    Publication date: November 5, 2009
    Inventor: Tadao Katsuragawa
  • Publication number: 20080311429
    Abstract: The disclosure provides a magnetic film which includes a titania nanosheet which is formed on a transparent substrate and contains a layered titanium oxide in which at least one magnetic element is substituted for a Ti lattice position, the titanium oxide being expressed by a formula: Ti2-xMxO4 where M is at least one kind of transition metal elements chosen from among V, Cr, Mn, Fe, Co, Ni, and Cu, and 0<x<2, a dispersant surrounding the nanosheet, and a water-soluble organic compound.
    Type: Application
    Filed: June 9, 2008
    Publication date: December 18, 2008
    Inventors: Tadao KATSURAGAWA, Takayoshi Sasaki, Minoru Osada
  • Patent number: 6993872
    Abstract: A light control window that includes at least a transparent window substrate and an optical element. The optical element includes at least an optical element main body configured to change the light transmittance through the window upon application of a magnetic field. The optical element main body includes at least a micro-magnetic head array configured to apply the magnetic field to the optical element main body.
    Type: Grant
    Filed: May 30, 2003
    Date of Patent: February 7, 2006
    Assignee: Ricoh Company, LTD
    Inventor: Tadao Katsuragawa
  • Publication number: 20040074165
    Abstract: A light control window that includes at least a transparent window substrate and an optical element. The optical element includes at least an optical element main body configured to change the light transmittance through the window upon application of a magnetic field. The optical element main body includes at least a micro-magnetic head array configured to apply the magnetic field to the optical element main body.
    Type: Application
    Filed: May 30, 2003
    Publication date: April 22, 2004
    Inventor: Tadao Katsuragawa
  • Patent number: 6243193
    Abstract: A magneto-optical light modulator includes a first polarizer, a transparent magneto-optical component including a magneto-optical film deposited on a surface of a substrate, and a second polarizer. The surface of the substrate includes features having a depth in a range of 0.1 &mgr;m to 5 &mgr;m. Side surfaces of the features are covered with the magneto-optical film to a thickness of 5 nm to 200 nm. Light flux from a light source passes through the first polarizer, the magneto-optical component and the second polarizer. Changes in incident light flux intensity can lead to rapid changes in the intensity of light flux transmitted through the magneto-optical light modulator.
    Type: Grant
    Filed: May 6, 1999
    Date of Patent: June 5, 2001
    Assignee: Ricoh Company, Ltd.
    Inventor: Tadao Katsuragawa
  • Patent number: 6187431
    Abstract: A magnetic recording medium has a transparent substrate with a plurality of grooves which extend parallel with each other at regular intervals, each of the grooves having inner side walls perpendicular to the transparent substrate and a space between adjacent side walls being constant, a magnetic material layer extending in the form of a stripe, provided on the surface of the inner side walls of each of the grooves, and a pair of dielectric multi-layers which are disposed so as to sandwich the transparent substrate therebetween.
    Type: Grant
    Filed: December 4, 1998
    Date of Patent: February 13, 2001
    Assignee: Ricoh Company, Ltd.
    Inventor: Tadao Katsuragawa
  • Patent number: 6055215
    Abstract: A magneto-optical device including a substrate which is transparent to light in a visible spectrum region and a plurality of ferromagnetic layers arranged thereon, each ferromagnetic layer preferably having a width ranging from 5 to 100 nanometers and a thickness ranging from 0.1 to 5 microns. The ferromagnetic layers are parallel to each other and separated by a distance ranging from 0.2 to 2 microns. The ferromagnetic layers are arranged preferably on the side walls of grooves formed parallel to each other in the transparent substrate.
    Type: Grant
    Filed: April 21, 1998
    Date of Patent: April 25, 2000
    Assignee: Ricoh Company, Ltd.
    Inventor: Tadao Katsuragawa
  • Patent number: 5991075
    Abstract: A polarizer and method of making the polarizer includes forming plural grooved lines on a surface of a supporting body that is transparent to visible light. The plural grooved lines are straight, concave and parallel to one another. Respective of the plural grooved lines include a sidewall portion that has a fine line formed thereon where the fine line constitutes a residual portion of a larger thin film that was subjected to an etching process. The fine line is composed of a semiconductor a metal or a combination of the two.
    Type: Grant
    Filed: November 25, 1997
    Date of Patent: November 23, 1999
    Assignee: Ricoh Company, Ltd.
    Inventors: Tadao Katsuragawa, Ikue Kawashima, Yasuhiro Satoh
  • Patent number: 5112466
    Abstract: An apparatus for forming a thin film having a vacuum container evacuated to high vacuum and receiving a gas for vapor deposition, a generation device for generating a material vapor, a counter electrode holding a substrate to be vapor-deposited, a first grid disposed between the generation device and the electrode for accelerating the vapor, and a filament for emitting thermions to ionize the vapor. The grid and counter electrode surfaces may be curved and parallel to each other, and a second grid for accelerating the vapor, having a potential which is negative with respect to the potential of the first grid, may be placed between the first grid and the electrode, in the vicinity of the electrode, and a device may be provided for moving the first grid with respect to the electrode on a predetermined track.
    Type: Grant
    Filed: September 14, 1990
    Date of Patent: May 12, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Wasaburo Ohta, Mikio Kinoshita, Tadao Katsuragawa
  • Patent number: 5112701
    Abstract: Magneto-optic recording media and production processes of the same in which a thin magnetic film comprising, as the main ingredient, nitrides of metal (Fe, Co and Ni) and having strong perpendicular magnetic anisotropy is formed directly or indirectly by way of a reflective layer on a non-magnetic support, providing that the reflective layer is formed on the thin magnetic film if the magnetic thin film is disposed directly on the non-magnetic support.
    Type: Grant
    Filed: March 23, 1989
    Date of Patent: May 12, 1992
    Assignee: Ricoh Company, Ltd.
    Inventor: Tadao Katsuragawa
  • Patent number: 4960072
    Abstract: An apparatus for forming a thin film having a vacuum container evacuated to high vacuum and receiving a gas for vapor deposition, a generation device for generating a material vapor, a counter electrode holding a substrate to be vapor-deposited, a first grid disposed between the generation device and the electrode for accelerating the vapor, and a filament for emitting thermions to ionize the vapor. The first grid and counter electrode surfaces may be curved and parallel to each other, and a second grid for accelerating the vapor, having a potential which is negative with respect to the potential of the first grid, may be placed between the first grid and the electrode, in the vicinity of the electrode, and a device may be provided for moving the first grid with respect to the electrode on a predetermined track.
    Type: Grant
    Filed: August 5, 1988
    Date of Patent: October 2, 1990
    Assignee: Ricoh Company, Ltd.
    Inventors: Wasaburo Ohta, Mikio Kinoshita, Tadao Katsuragawa
  • Patent number: RE42824
    Abstract: A magneto-optical device including a substrate which is transparent to light in a visible spectrum region and, a plurality of ferromagnetic layers arranged thereon, each ferromagnetic layer preferably having a width ranging from in an inclusive range of 5 to through 100 nanometers and a thickness ranging from in an inclusive range of 0.1 to through 5 microns. The, wherein said ferromagnetic layers are parallel to each other and separated by a distance ranging from in an inclusive range of 0.2 to through 2 microns. The ferromagnetic layers are arranged preferably on the side walls of grooves formed parallel to each other in the transparent substrate.
    Type: Grant
    Filed: April 24, 2002
    Date of Patent: October 11, 2011
    Assignee: Ricoh Company, Ltd.
    Inventor: Tadao Katsuragawa