Patents by Inventor Ryu Ohtaguro

Ryu Ohtaguro 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).

  • Substrate for photomask, photomask blank and photomask
    Patent number: 7323276
    Abstract: A substrate for photomask has a top surface and a back surface, the substrate being square in shape, an end surface formed along the thickness thereof and a chamfered surface formed on a perimeter edge region where the end surface and the top surface meet and another region where the end surface and the back surface meet, a size of the perimeter edge of the substrate is 300 mm or more on a side and the end surface and the chamfered surface each has a roughened surface having a surface roughness (Ra) ranging from 0.03 ?m to 0.3 ?m.
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: January 29, 2008
    Assignee: Hoya Corporation
    Inventors: Ryu Ohtaguro, Koichi Hashiguchi
  • Substrate for photomask, photomask blank and photomask
    Publication number: 20040248017
    Abstract: A substrate for photomask has a top surface and a back surface, the substrate being square in shape, an end surface formed along the thickness thereof and a chamfered surface formed on a perimeter edge region where the end surface and the top surface meet and another region where the end surface and the back surface meet, a size of the perimeter edge of the substrate is 300 mm or more on a side and the end surface and the chamfered surface each has a roughened surface having a surface roughness (Ra) ranging from 0.03 &mgr;m to 0.3 &mgr;m.
    Type: Application
    Filed: March 25, 2004
    Publication date: December 9, 2004
    Applicant: HOYA CORPORATION
    Inventors: Ryu Ohtaguro, Koichi Hashiguchi