Patents by Inventor Koji Fujitaka

Koji Fujitaka 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).

  • Short arc discharge lamp
    Patent number: 8716934
    Abstract: Disclosed herein is a short arc discharge lamp which has a cathode electrode structure formed by solid-phase bonding a tip part made of thoriated tungsten to a body part made of tungsten. In the present invention, thorium can be reliably diffused onto the surface of the cathode electrode over a long period of time without stagnation of reduction of thorium oxide in the tip part. Therefore, satisfactory emission characteristics can be provided, whereby the arc stability is more reliable. The cathode electrode of the present invention is characterized in that potassium concentration of the body part is higher than potassium concentration of the tip part.
    Type: Grant
    Filed: May 17, 2013
    Date of Patent: May 6, 2014
    Assignee: Ushio Denki Kabushiki Kaisha
    Inventors: Koji Fujitaka, Hirohisa Iwabayashi
  • SHORT ARC DISCHARGE LAMP
    Publication number: 20130320845
    Abstract: Disclosed herein is a short arc discharge lamp which has a cathode electrode structure formed by solid-phase bonding a tip part made of thoriated tungsten to a body part made of tungsten. In the present invention, thorium can be reliably diffused onto the surface of the cathode electrode over a long period of time without stagnation of reduction of thorium oxide in the tip part. Therefore, satisfactory emission characteristics can be provided, whereby the arc stability is more reliable. The cathode electrode of the present invention is characterized in that potassium concentration of the body part is higher than potassium concentration of the tip part.
    Type: Application
    Filed: May 17, 2013
    Publication date: December 5, 2013
    Applicant: Ushio Denki Kabushiki Kaisha
    Inventors: Koji Fujitaka, Hirohisa Iwabayashi