Patents by Inventor Young Gu Ju

Young Gu Ju 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).

  • Publication number: 20020075922
    Abstract: Disclosed is a surface-emitting laser device which eliminates an absorption loss of a p-type doped layer and reduces a scattering loss in a mirror layer and a carrier loss due to a current induction, comprising a first conductive type of semiconductor substrate; a bottom mirror layer formed on the semiconductor substrate and composed of a first conductive type of semiconductor layer; an active layer formed on the bottom mirror layer; an electron leakage barrier layer formed on the active layer and having an energy gap larger than the active layer; a current induction layer formed on the electron leakage barrier layer and a second conductive type of semiconductor layer; a current extension layer formed on the current induction layer and composed of the second conductive type of semiconductor layer; and a top mirror layer formed on the current extension layer, wherein the top mirror layer includes undoped center portion and its both end having the second conductive type of dopant diffusion region.
    Type: Application
    Filed: April 25, 2001
    Publication date: June 20, 2002
    Inventors: Byueng-Su Yoo, O-Kyun Kwon, Young-Gu Ju
  • Patent number: 6253004
    Abstract: An optical interconnection structure between an optoelectric device and a single mode optical fiber for enlarging an alignment tolerance is provided. The optical interconnection structure is constituted by a microlensed optoelectric device and a graded index fiber ended single mode optical fiber. Light beams emitted from the optoelectric device are collimated by the microlens on the rear surface of a substrate or are enlarged in size by being focused or diverged. The extended output light travels a predetermined distance and then reaches the graded index fiber ended single mode optical fiber. When the length of the graded index optical fiber lens is appropriate, the incident extended beams are again focused by the lens, and thus enter into the single mode optical fiber while maintaining a great coupling efficiency. The optoelectric device and the microlens are integrated by the photolithography process, such that alignment with respect to all elements within a substrate is accomplished.
    Type: Grant
    Filed: July 9, 1999
    Date of Patent: June 26, 2001
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Yong Hee Lee, Young Gu Ju, Myung Lae Lee