Patents by Inventor Tetu Okamoto

Tetu Okamoto 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 type ultra-high pressure discharge lamp
    Patent number: 6713949
    Abstract: The present invention is a short arc type ultra-high pressure discharge lamp in which a pair of electrodes 3 are disposed inside an arc tube 1 that comprises quartz glass, seal portions 2 are formed that comprise quartz glass and extend to both sides of the arc tube 1, and at least 0.15 mg/mm3 of mercury is filled into the arc tube 1, wherein a metal foil 4 is embedded in each of the seal portions 2, and metal granular lumps 6 are protrusively provided on surfaces of each metal foil 4.
    Type: Grant
    Filed: October 16, 2002
    Date of Patent: March 30, 2004
    Assignee: Ushio Denki Kabushiki Kaisha
    Inventors: Kensuke Fukushima, Tetu Okamoto
  • Super-high pressure mercury lamp
    Patent number: 6653786
    Abstract: A high pressure mercury lamp for a projector device in which a discharge vessel made of quartz glass is filled with at least 0.15 mg/mm3 mercury in which both devitrification of as well as damage to the discharge vessel can be eliminated is obtained by the quartz glass of the discharge vessel being given a fictive temperature of 1000° C. to 1250° C., a total content of alkali metals of 0.1 ppm by weight to 3 ppm by weight and an aluminum content of from 1 ppm by weight to 30 ppm by weight.
    Type: Grant
    Filed: May 22, 2002
    Date of Patent: November 25, 2003
    Assignee: Ushiodenki Kabushiki Kaisha
    Inventors: Kensuke Fukushima, Tetu Okamoto
  • Short arc type ultra-high pressure discharge lamp
    Publication number: 20030094899
    Abstract: The present invention is a short arc type ultra-high pressure discharge lamp in which a pair of electrodes 3 are disposed inside an arc tube 1 that comprises quartz glass, seal portions 2 are formed that comprise quartz glass and extend to both sides of the arc tube 1, and at least 0.15 mg/mm3 of mercury is filled into the arc tube 1, wherein a metal foil 4 is embedded in each of the seal portions 2, and metal granular lumps 6 are protrusively provided on surfaces of each metal foil 4.
    Type: Application
    Filed: October 16, 2002
    Publication date: May 22, 2003
    Applicant: Ushio Denki Kabushiki Kaisya
    Inventors: Kensuke Fukushima, Tetu Okamoto
  • Super-high pressure mercury lamp
    Publication number: 20020175624
    Abstract: A high pressure mercury lamp for a projector device in which a discharge vessel made of quartz glass is filled with at least 0.15 mg/mm3 mercury in which both devitrification of as well as damage to the discharge vessel can be eliminated is obtained by the quartz glass of the discharge vessel being given a fictive temperature of 1000° C. to 1250° C., a total content of alkali metals of 0.1 ppm by weight to 3 ppm by weight and an aluminum content of from 1 ppm by weight to 30 ppm by weight.
    Type: Application
    Filed: May 22, 2002
    Publication date: November 28, 2002
    Applicant: Ushiodenki Kabushiki Kaisha
    Inventors: Kensuke Fukushima, Tetu Okamoto