Patents by Inventor Jeff Tsao

Jeff Tsao 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: 20120106540
    Abstract: The present invention is a method for securing internet communications between various voice over IP (VoIP) applications. The method enables VoIP Devices to operate within multiple IP networks which are physically connected to the VoIP Device in a manner that ensures inbound and outbound network traffic separation from other connected IP networks based on applicable Security Classifications of the VoIP Device and/or VoIP Device user.
    Type: Application
    Filed: November 1, 2010
    Publication date: May 3, 2012
    Inventors: Tim Moyers, Jeff Tsao
  • Patent number: 6696308
    Abstract: A method of fabricating an electrically pumped, long-wavelength vertical cavity surface emitting laser includes epitaxially growing a stack of alternate layers of a first material and a second material on a compatible substrate. A long wave-length active region is epitaxially grown on the stack and a lasing aperture and current confinement volume are defined in the long wave-length active region. A first mirror stack is formed on the long wave-length active region and portions of one of the first material and the second material are removed to form a high reflectivity second mirror stack.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: February 24, 2004
    Inventors: Chan-Long Shieh, Jeff Tsao
  • Patent number: 6594294
    Abstract: A segmented-mirror vertical cavity surface emitting laser includes an active portion with an active region having at least one quantum well and a lateral dimension. A first mirror stack is positioned on a first opposed major surface of the active portion and extends laterally beyond the lateral dimension of the active region. A second mirror stack is positioned on the opposed major surface and extends laterally beyond the lateral dimension of the active region. The second mirror stack is segmented into two or more zones. In the case where there are two zones, in the first zone there would be a first reflectivity and a first thermal impedance, and in the second zone there would be a second reflectivity lower than the first reflectivity and a second thermal impedance lower than the first thermal impedance.
    Type: Grant
    Filed: March 7, 2001
    Date of Patent: July 15, 2003
    Inventors: Jeff Tsao, Chan-Long Shieh, P. Daniel Dapkus, Jay Yang
  • Patent number: 6556610
    Abstract: Semiconductor lasers are formed by integrating an electrically pumped semiconductor laser, a beam steering element and a vertical cavity surface emitting laser (VCSEL) together. The electrically pumped semiconductor laser is modulated to modulate a pump beam of photons at a first wavelength. The beam steering element directs the pump beam to the VCSEL to provide optical pumping. The VCSEL receives the pump beam of photons at the first wavelength and is stimulated to emit photons of a laser beam at a second wavelength longer than the first. In embodiments, index guiding is provided in the VCSEL to improve the optical pumping and emission efficiencies when the pump beam is modulated at high frequencies. Embodiments of the beam steering element include a silicon bench, a polymer element, and a facet included in the edge emitting laser and an external mirror. Embodiments of index guiding include an air gap to form a mesa and an oxide confinement ring shaped layer.
    Type: Grant
    Filed: April 12, 2001
    Date of Patent: April 29, 2003
    Assignee: E20 Communications, Inc.
    Inventors: Wenbin Jiang, Chan-Long Shieh, Xiqing Sun, Jeff Tsao, Hsing-Chung Lee
  • Patent number: 6542530
    Abstract: An electrically pumped, long-wavelength VCSEL includes a long wavelength active region having electrical contacts on opposed sides thereof. A layer of semiconductor material is included in the active region having an electrically conductive portion defining a lasing aperture and current confinement volume with the conductive portion being limited by an electrically insulating portion. Windows are formed in the electrical contacts in alignment with the lasing aperture and mirror stacks are positioned on the long wavelength active region in each of the windows. At least one of the mirror stacks includes a metamorphic distributed Bragg reflector for heat conduction.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: April 1, 2003
    Inventors: Chan-Long Shieh, Jeff Tsao