Patents by Inventor Tsuneyoshi Itoh

Tsuneyoshi Itoh 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).

  • Edge processing of chemically toughened lenses
    Patent number: 3981709
    Abstract: In a toughened lens which has been subjected to chemical tempering process and then to edge grinding, the fracture strength can be greatly enhanced if the peripheral portion is chamfered with the angle of chamfering to the tangential line on the optical surface of the lens not greater than 45.degree.. This toughened effect is further increased by subjecting the chamfered peripheral portion to such a post treatment as mechanical polishing, chemical etching or thermal polishing.
    Type: Grant
    Filed: April 7, 1975
    Date of Patent: September 21, 1976
    Assignee: Tokyo Kogaku Kikai Kabushiki Kaisha
    Inventors: Fumio Kondo, Masayuki Kondo, Tsuneyoshi Itoh, Koji Sato