Patents by Inventor Atsuhi Shimada

Atsuhi Shimada 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).

  • Method for welding a quartz glass tube for use as an optical fiber preform
    Patent number: 6484540
    Abstract: A method for welding a dummy tube to a quartz glass tube for use as an optical fiber preform, comprising chamfering the inner edge portion of the dummy tube and/or the quartz glass tube for use as the optical fiber preform before welding the quartz glass tube for use as the optical fiber preform with the dummy tube, and then melt welding them together.
    Type: Grant
    Filed: August 11, 2000
    Date of Patent: November 26, 2002
    Assignees: Heraeus Quarzglas GmbH & Co. KG, Shin-Etsu Quartz Products Co., Ltd.
    Inventors: Atsuhi Shimada, Toshiyuki Kato, Masanori Suzuki, Yutaka Watabe
  • Rod in tube method of forming a fiber preform, with maintaining a gas supply until after an end is stretched
    Patent number: 6425270
    Abstract: A method for producing an optical fiber preform comprising inserting a core glass rod for use in the optical fiber preform into the quartz glass tube for the optical fiber preform and then welding them in a heating furnace to melt weld them together into a monolithic product, wherein the melting is started in such a state that the lower open edge of said quartz glass tube is placed inside the heating furnace and a gas is supplied from the upper edge of the tube, and after the lower edge portion of the quartz glass tube is drawn out from said heating furnace by melt deformation and stretching by the gravitational force, the gas supply is cut off and the pressure is reduced.
    Type: Grant
    Filed: July 7, 2000
    Date of Patent: July 30, 2002
    Assignees: Heraeus Quarzglas GmbH & Co. KG, Shin-Etsu Quartz Products Co., Ltd.
    Inventors: Masanori Suzuki, Toshiyuki Kato, Atsuhi Shimada, Yutaka Watabe