Patents by Inventor Tu Zhang

Tu Zhang 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).

  • Low threshold vertical cavity surface emitting laser
    Patent number: 5420880
    Abstract: In a VCSEL, vertical cavity surface emitting laser, lateral traveling mode density is reduced by reducing the number of traveling modes available to spontaneous emission of photons in the active cavity region, to suppress spontaneous emission into lateral traveling modes, to increase spontaneous emission into axial normal modes, to lower lasing threshold. The sidewall of the active cavity region is contoured, preferably by a 90.degree. symmetrical V-shaped notch, to internally reflect laterally traveling photons, to suppress lateral traveling modes.
    Type: Grant
    Filed: October 12, 1993
    Date of Patent: May 30, 1995
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Ned Tabatabaie, Tu Zhang
  • Charger connector
    Patent number: D570286
    Type: Grant
    Filed: July 31, 2007
    Date of Patent: June 3, 2008
    Assignee: Cheng Uei Precision Industry Co., Ltd.
    Inventors: Li-Li Shen, Hong Tu Zhang, Mao Jung Huang
  • SIM card connector
    Patent number: D570291
    Type: Grant
    Filed: September 21, 2007
    Date of Patent: June 3, 2008
    Assignee: Cheng Uei Precision Industry Co., Ltd.
    Inventor: Hong Tu Zhang