Patents by Inventor Chiyuki Kitahara

Chiyuki Kitahara 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 of manufacturing semiconductor laser for communication, semiconductor laser for communication and optical transmission module
    Patent number: 7833807
    Abstract: Some semiconductor lasers have an initial failure mode that is advanced as the amount of optical power therein, namely, the amount of optical output observed from the outside increases in almost independent of the temperature. The initial failure mode that is advanced as the amount of optical output increases is not sufficiently screened, so that the initial failure rate is somewhat higher than that of the semiconductor laser having the conventional active layer material. It is effective to introduce a test with large optical output at lower temperature than average operating temperature such as room temperature, during the manufacturing process. This helps to eliminate elements having the initial failure mode that is advanced as the amount optical output increases, thereby to extend the expected life of the laser diodes.
    Type: Grant
    Filed: August 2, 2007
    Date of Patent: November 16, 2010
    Assignee: Opnext Japan, Inc.
    Inventors: Hiroyuki Kamiyama, Masaru Mukaikubo, Hiroaki Inoue, Chiyuki Kitahara
  • Method of manufacturing semiconductor laser for communication, semiconductor laser for communication and optical transmission module
    Publication number: 20080089378
    Abstract: Some semiconductor lasers have an initial failure mode that is advanced as the amount of optical power therein, namely, the amount of optical output observed from the outside increases in almost independent of the temperature. The initial failure mode that is advanced as the amount of optical output increases is not sufficiently screened, so that the initial failure rate is somewhat higher than that of the semiconductor laser having the conventional active layer material. It is effective to introduce a test with large optical output at lower temperature than average operating temperature such as room temperature, during the manufacturing process. This helps to eliminate elements having the initial failure mode that is advanced as the amount optical output increases, thereby to extend the expected life of the laser diodes.
    Type: Application
    Filed: August 2, 2007
    Publication date: April 17, 2008
    Inventors: Hiroyuki Kamiyama, Masaru Mukaikubo, Hiroaki Inoue, Chiyuki Kitahara