Patents by Inventor Riyopoulos Spilios

Riyopoulos Spilios 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: 20040209386
    Abstract: A semiconductor laser, for example a Vertical Cavity Surface Emitting Laser (VCSEL), includes one or more photoactive layers to improve the fundamental mode operation of lasing. The photoactive layer(s) provides on-axis current channeling, resulting from the selective drop in resistance around the center of the photoactive layer(s) due to photo-excitation, and counteracts “hole burning” (i.e., carrier depletion) of the center axis region of the VCSEL cylinder. The photoactive layer(s) act as a variable resistivity screen(s) whose radial aperture is controlled by the light itself. The absorption of a small traction of the light intensity suffices for significant on-axis current peaking with minimum efficiency loss and optical mode distortion. Thus, the VCSEL has optically pumped photoactive layers that induce significant, self-regulated, on-axis current channeling and fundamental mode stability at high operation current, improving lasing operation.
    Type: Application
    Filed: May 14, 2004
    Publication date: October 21, 2004
    Applicant: Science Applications International Corporation
    Inventor: Riyopoulos Spilios
  • Patent number: 6795470
    Abstract: A semiconductor laser, for example a Vertical Cavity Surface Emitting Laser (VCSEL), includes one or more photoactive layers to improve the fundamental mode operation of lasing. The photoactive layer(s) provides on-axis current channeling, resulting from the selective drop in resistance around the center of the photoactive layer(s) due to photo-excitation, and counteracts“hole burning” (i.e. carrier depletion) of the center axis region of the VCSEL cylinder. The photoactive layer(s) act as a variable resistivity screen(s) whose radial aperture is controlled by the light itself. The absorption of a small fraction of the light intensity suffices for significant on-axis current peaking with minimum efficiency loss and optical mode distortion. Thus, the VCSEL has optically pumped photoactive layers that induce significant, self-regulated, on-axis current channeling and fundamental mode stability at high operation current, improving lasing operation.
    Type: Grant
    Filed: June 9, 1999
    Date of Patent: September 21, 2004
    Assignee: Science Applications International Corporation
    Inventor: Riyopoulos Spilios