Patents by Inventor Shigeru Ehata

Shigeru Ehata 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: 5021705
    Abstract: An image pick-up tube and a method of fabricating an image pick-up tube and a target section used therewith, in which the target includes at least a conductive film and a photoconductive film on a substrate for photo-electric conversion, and a signal from the target section is read by an electron beam scanning system. At least a part of the surface area outside the effective scanning region of the electron beam scanning side of the target section is formed of a secondary electron emission dampening layer.
    Type: Grant
    Filed: May 24, 1989
    Date of Patent: June 4, 1991
    Assignees: Hitachi Ltd., Nippon Hoso Kyokai
    Inventors: Masanao Yamamoto, Takaaki Unnai, Shigeru Ehata, Tadaaki Hirai, Kenji Sameshima, Eikiyu Hiruma, Shirou Suzuki, Kenkichi Tanioka, Junichi Yamazaki, Keiichi Shidara
  • Patent number: 4467243
    Abstract: An electron gun is disclosed which includes a thermionic cathode for emitting an electron beam, a grid having a first aperture for controlling the diameter of the electron beam, and an anode having a second aperture for catching a part of the electron beam having passed through the first aperture; and in which the diameter of the first aperture is smaller than or equal to the diameter of the second aperture, and the grid and the anode are applied with positive potentials relative to a cathode potential, for example, with a voltage of 5 to tens of volts and a voltage of 100 to 500 volts, respectively, to form a uniform axial field between the grid and the anode, thereby generating a laminar flow electron beam having a constant current density.
    Type: Grant
    Filed: October 28, 1981
    Date of Patent: August 21, 1984
    Assignees: Hitachi, Ltd., Nippon Hoso Kyokai
    Inventors: Masakazu Fukushima, Masanori Maruyama, Shigeru Ehata, Chihaya Ogusu, Yukinao Isozaki
  • Patent number: 4427917
    Abstract: A television camera tube with electrostatic focusing comprising a triode section at the first stage having a cathode a first grid and a second grid, an electrostatic focusing lens section at the next stage having a third, fourth and fifth grids of cylindrical electrode configuration, and a sixth grid with mesh electrode configuration at the last stage, these electrodes being coaxially arranged in a cylindrical glass envelope, the length of the fourth grid is greater than 1.15 times the inner diameter thereof but equal to or smaller than 2.30 times the inner diameter thereof.
    Type: Grant
    Filed: September 13, 1982
    Date of Patent: January 24, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Masashi Mizushima, Shigeru Ehata, Masanori Maruyama, Masakazu Fukushima
  • Patent number: 4363996
    Abstract: A vidicon type camera tube comprising a beam current control section including a thermionic cathode, a first grid having an aperture of diameter d.sub.1, a second grid having an aperture of diameter d.sub.2 and a beam disc having a diaphragm of diameter d.sub.3 disposed at a distance of l along the tube axis from the second grid. The tube further comprises a main lens section constituted of cylindrical electrodes. The diameters d.sub.1, d.sub.2 and d.sub.3 and the distance l are so determined that the value of (d.sub.2 /l)(d.sub.3 /d.sub.1).sup.2 may lie in the range where the difference of the effective cathode loading is positive.
    Type: Grant
    Filed: December 11, 1980
    Date of Patent: December 14, 1982
    Assignee: Hitachi, Ltd.
    Inventors: Masashi Mizushima, Masanori Maruyama, Shigeru Ehata, Masakazu Fukushima
  • Patent number: 4169239
    Abstract: The electron lens of an electrostatically focusing type image pickup tube comprises three coaxially arranged cylindrical electrodes and the inner diameters thereof are decreased from the side of a target toward an electron gun. The electron lens is assembled by successively fitting the three electrodes over a mandrel, the outer diameter thereof varying stepwisely in accordance with the inner diameters of the three electrodes, and then interconnecting the three electrodes by axially extending insulating supporting rods.
    Type: Grant
    Filed: July 25, 1977
    Date of Patent: September 25, 1979
    Assignee: Hitachi, Ltd.
    Inventors: Shigeru Ehata, Hideyuki Sakai, Kinjir Gunbe