Patents by Inventor Masafumi Kondo

Masafumi Kondo 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).

  • Semiconductor laser device
    Patent number: 4750183
    Abstract: An active layer for laser oscillation and optical guiding layers for guiding laser light sandwiching the active layer therebetween are included in the device. At least one of the optical guiding layers is formed by a superlattice, the optical refractive index of which is lower than that of the active layer. Further, the optical refractive index is gradually decreased in the direction from the portion of the optical guiding layer adjacent to the active layer, to the outside of the optical guiding layer.
    Type: Grant
    Filed: February 18, 1987
    Date of Patent: June 7, 1988
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Kohsei Takahashi, Toshiro Hayakawa, Takahiro Suyama, Masafumi Kondo, Saburo Yamamoto
  • Separate confinement heterostructure semiconductor laser device
    Patent number: 4745612
    Abstract: The laser device has an Al.sub.x Ga.sub.1-x As (x.gtoreq.0.3) quantum well active region having a thickness of 200 angstroms or less. Al.sub.y Ga.sub.1-y As (y>x) carrier supplying layers sandwich the quantum well active region therebetween. An Al.sub.z Ga.sub.1-z As (z>y) cladding layer is disposed on each of the carrier supplying layers. Finally an Al.sub.w Ga.sub.1-w As (w>z) barrier layer is disposed between each of the carrier supplying layers and each of the cladding layers.
    Type: Grant
    Filed: July 11, 1986
    Date of Patent: May 17, 1988
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshiro Hayakawa, Takahiro Suyama, Kohsei Takahashi, Masafumi Kondo, Saburo Yamamoto