Patents by Inventor Thomas Aggerstam

Thomas Aggerstam 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).

  • Transverse mode and polarization control of surface emitting lasers through the formation of a dielectric stack
    Patent number: 6885690
    Abstract: A vertical cavity surface emitting laser (VCSEL) having asymmetrical optical confinement is described. Polarization of VCSELs having symmetrical structures tend to be unpredictable and switchable. The VCSEL of the present invention has a dielectric stack on top of the emitting distributed Bragg mirror. The stack is made up of two or more layers of dielectric material with each alternate layer having one of two different refractive indexes. In a preferred embodiment an antireflective coating is between the top mirror and the dielectric layers. The stack is preferably smaller than the emitting aperture.
    Type: Grant
    Filed: September 12, 2002
    Date of Patent: April 26, 2005
    Assignee: Zarlink Semiconductor AB
    Inventors: Thomas Aggerstam, Rickard von Wurtemberg
  • Transverse mode and polarization control of surface emitting lasers through the formation of a dielectric stack
    Publication number: 20030063642
    Abstract: A vertical cavity surface emitting laser (VCSEL) having asymmetrical optical confinement is described. Polarization of VCSELs having symmetrical structures tend to be unpredictable and switchable. The VCSEL of the present invention has a dielectric stack on top of the emitting distributed Bragg mirror. The stack is made up of two or more layers of dielectric material with each alternate layer having one of two different refractive indexes. In a preferred embodiment an antireflective coating is between the top mirror and the dielectric layers. The stack is preferably smaller than the emitting aperture.
    Type: Application
    Filed: September 12, 2002
    Publication date: April 3, 2003
    Applicant: Zarlink Semiconductor AB
    Inventors: Thomas Aggerstam, Rickard von Wurtemberg
  • Polarization controlled VCSELs using an asymmetric current confining aperture
    Publication number: 20030007531
    Abstract: A vertical cavity surface emitting laser (VCSEL) having asymmetrical optical confinement is described. Polarization of VCSELs having symmetrical structures tend to be unpredictable and switchable. The VCSEL of the present invention has vertically etched apertures into the top bragg mirror in order to confine the optical path into an asymmetric structure. This has the effect of locking polarization into a fixed mode.
    Type: Application
    Filed: June 25, 2002
    Publication date: January 9, 2003
    Applicant: Zarlink Semiconductor AB
    Inventor: Thomas Aggerstam