Patents by Inventor Keiji Segawa

Keiji Segawa 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: 6411194
    Abstract: The invention provides a production method capable of forming a thin film resistance element having a thickness and a shape controlled in a high accuracy in a printed circuit board. The production method of a thin film resistance element formed on a printed circuit board, has the steps of forming a thin film resistance layer having a predetermined thickness on the printed circuit board through an insulation layer by a dry process used in producing a semiconductor, forming an electrically conductive layer on the thin resistance layer, and etching the electrically conductive layer selectively so as to make, at least, a pair of electrically conductive pads, resulting in the thin film resistance element having a predetermined value of resistivity between the pair of electrically conductive pads. Thereby, it is possible to form the thin film resistance element having a thickness and a shape controlled in a high accuracy on the printed circuit board.
    Type: Grant
    Filed: February 27, 2001
    Date of Patent: June 25, 2002
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Motoshi Shindoh, Keiji Segawa, Mitsuru Otsuki
  • Publication number: 20010026211
    Abstract: The invention provides a production method capable of forming a thin film resistance element having a thickness and a shape controlled in a high accuracy in a printed circuit board (core material). The production method of a thin film resistance element formed on a printed circuit board, has the steps of forming a thin film resistance layer having a predetermined thickness on the printed circuit board through an insulation layer by a dry process used in producing a semiconductor, forming an electrically conductive layer on the thin resistance layer, and etching the electrically conductive layer selectively so as to make, at least, a pair of electrically conductive pads, resulting in the thin film resistance element having a predetermined value of resistivity between the pair of electrically conductive pads. Thereby, it is possible to form the thin film resistance element having a thickness and a shape controlled in a high accuracy on the printed circuit board (core material).
    Type: Application
    Filed: February 27, 2001
    Publication date: October 4, 2001
    Inventors: Motoshi Shindoh, Keiji Segawa, Mitsuru Otsuki
  • Patent number: 4675765
    Abstract: A magnetic recording and/or reproducing element comprises a main element body, and windings wound around the main element body. The main element body has a pair of extremely thin layers made from a ferromagnetic material, and the extremely thin layers oppose each other at respective edges thereof so as to constitute a gap. Each of the thin layers are sandwiched between a pair of support members which are made from a non-magnetic and abrasion proof material. A contact surface is formed on a vertex part of the main element body, for making contact with a magnetic recording medium so as to record and/or reproduce a signal on and/or from the magnetic recording medium. The main element body has one or a plurality of side surfaces which form a predetermined angle with respect to the contact surface and define the peripheral edge of the contact surface so that the contact surface has a predetermined shape with an extremely small area and has the gap at an approximate center of the predetermined shape.
    Type: Grant
    Filed: December 20, 1984
    Date of Patent: June 23, 1987
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Keiji Segawa, Hirofumi Imaoka, Hisao Kinjo, Toshiya Sakurai
  • Patent number: 4498163
    Abstract: An electrostatic capacitance type pickup stylus for use on an information storage disc comprises a crystal of diamond including a sliding face for slidable contact with the information storage disc, an electrode face supporting thereon a conductive electrode layer for detecting signals on the information storage disc as changes in electrostatic capacitance, a pair of first and second angularly spaced back faces adjoining the electrode face, and a pair of first and second angularly spaced guide faces adjoining each other and the first and second back faces, respectively.
    Type: Grant
    Filed: July 30, 1982
    Date of Patent: February 5, 1985
    Assignee: Victor Company of Japan, Limited
    Inventors: Keiji Segawa, Mikio Naoi, Masaki Murakami
  • Patent number: 4488281
    Abstract: A capacitance detection type record stylus comprises a conductive shank and a diamond partially embedded in the shank so that the diamond projects downwardly from one end of the shank. The shank is formed with a bottom face for making slidable contact with the disk record. The shank and diamond are formed with a pair of common rear faces inclined with respect to the axis of the stylus to define an electrode forming face therebetween which extends from the bottom face of the diamond partially into the shank. The electrode forming face is inclined at an acute angle with respect to the axis so that the lower end of the electrode forming face is located at a point forward with respect to the upper end thereof and subtends at the lower end thereof at such an angle that the diamond can be lapped without causing defects to occur on the lapped surfaces.
    Type: Grant
    Filed: March 12, 1982
    Date of Patent: December 11, 1984
    Assignee: Victor Company of Japan, Limited
    Inventors: Hideaki Takehara, Yoshiyo Wada, Kunio Goto, Keiji Segawa
  • Patent number: 4410974
    Abstract: A capacitance detection type record stylus comprises a body of artificial diamond having flat faces lying parallel to the crystal planes {111} and {100} wherein adjoining identical crystal planes are either {111} or {100}. A crystal plane {110} is formed between any two of the adjoining identical crystal planes by lapping the edge between them. A conductive material is deposited on the crystal plane {110} to form an electrode for detecting signals recorded as geometric variations on a recording medium. Because of the aligned carbon atoms beneath the crystal plane {110}, a substantial amount of the conductive material penetrates deeply into the diamond making the electrode resistant to wear.
    Type: Grant
    Filed: September 8, 1981
    Date of Patent: October 18, 1983
    Assignee: Victor Company of Japan, Limited
    Inventors: Keiji Segawa, Masaki Murakami, Keiichiro Doi
  • Patent number: 4398282
    Abstract: A cylindrical diamond body is shaped to form a truncated conical portion. A conductive layer is deposited on the diamond body extending from the truncated end to the other end of the body. The conical portion of the body with the conductive layer being attached thereto is lapped to remove portions of the layer and the diamond body to form a pair of substantially flat surfaces extending from the truncated end toward the opposite end leaving the conductive layer to form a narrow width electrode for picking just one information signal stored in the form of minute pits along a spiral track or concentric tracks.
    Type: Grant
    Filed: May 8, 1981
    Date of Patent: August 9, 1983
    Assignee: Victor Company of Japan, Limited
    Inventors: Keiji Segawa, Norio Matsuda, Masaki Murakami
  • Patent number: 4120742
    Abstract: A stylus for the capacitive pickup of information signals inscribed in a recording medium as a geometrical variation comprises a corundum single crystal rod having two parallel side faces, which are inherently flat and optically smooth, and a thin electrode film coated on one of these two side faces. The electrode film is normal to the c-axis of the crystal, and the longitudinal axis of the rod coincides with one of the a-axes. The rod is formed by the "edge defined film fed growth" method, wherein corundum melt is made to spread as a film over a flat shape-defining surface and a seed crystal is pulled vertically through a capillary so that an elongated crystal is continuously grown. The c-axes of the grown and seed crystals are parallel to the shape-defining surface and normal to the growth direction. Thereby, the rod is formed without the need of machining and abrading steps, other than steps for the shaping of a tip.
    Type: Grant
    Filed: October 28, 1976
    Date of Patent: October 17, 1978
    Assignee: Victor Company of Japan, Limited
    Inventors: Akira Asano, Keiji Segawa