Patents by Inventor Tun-Sein Tan

Tun-Sein Tan 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).

  • Patent number: 7087941
    Abstract: The extraction efficiency of a light emitting device can be improved by making the absorbing device layers as thin as possible. The internal quantum efficiency decreases as the device layers become thinner. An optimal active layer thickness balances both effects. An AlGaInP LED includes a substrate and device layers including an AlGaInP lower confining layer of a first conductivity type, an AlGaInP active region of a second conductivity type, and an AlGaInP upper confining layer of a second conductivity type. The absorbance of the active region is at least one fifth of the total absorbance in the light-emitting device. The device optionally includes at least one set-back layers of AlGaInP interposing one of confining layer and active region. The p-type upper confining layer may be doped with oxygen improve the reliability.
    Type: Grant
    Filed: November 5, 2001
    Date of Patent: August 8, 2006
    Assignee: Philips Lumileds Lighting Company, LLC
    Inventors: Nathan F. Gardner, Fred A. Kish, Herman C. Chui, Stephen A. Stockman, Michael R. Krames, Gloria E. Hofler, Christopher Kocot, Nicolas J. Moll, Tun-Sein Tan
  • Patent number: 6750973
    Abstract: A test structure supports simultaneous characterization of a two port optical component. The test structure includes an input port for receiving an input signal from an optical source, two test ports for connecting the test structure to a component under test, separate optical paths for supplying reflected and transmitted optical response signals from the component under test to separate receivers, and optical components for combining a first portion of the input signal with the reflected optical response signal before the first portion of the input signal and the reflected optical response signal are detected by a first receiver and for combining a second portion of the input signal with the optical response signal before the second signal and the optical response signal are detected by a second receiver. The optical component of the test structure may be connected by optical fibers or integrated into a single substrate.
    Type: Grant
    Filed: February 20, 2002
    Date of Patent: June 15, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: Tun Sein Tan, Douglas M. Baney
  • Patent number: 6649440
    Abstract: A light-emitting diode (LED) and a method of making the device utilize a thick multi-layered epitaxial structure that increases the light extraction efficiency of the device. The LED is an aluminum-gallium-indium-nitride (AlGaInN)-based LED. The thick multi-layered epitaxial structure increases the light extraction efficiency of the device by increasing the amount of emitted light that escapes the device through the sides of the thick multi-layered epitaxial structure. The LED includes a substrate, a buffer layer, and the thick multi-layered epitaxial structure. In the preferred embodiment, the substrate is a sapphire substrate having a textured surface. The textured surface of the substrate randomized light impinges the textured surface, so that an increased amount of emitted light may escape the LED as output light. The multi-layered epitaxial structure includes an upper AlGaInN region, an active region, and a lower AlGaInN region.
    Type: Grant
    Filed: July 17, 2000
    Date of Patent: November 18, 2003
    Assignee: Lumileds Lighting U.S., LLC
    Inventors: Michael Ragan Krames, Paul Scott Martin, Tun Sein Tan
  • Publication number: 20030156295
    Abstract: A test structure supports simultaneous characterization of a two port optical component. The test structure includes an input port for receiving an input signal from an optical source, two test ports for connecting the test structure to a component under test, separate optical paths for supplying reflected and transmitted optical response signals from the component under test to separate receivers, and optical components for combining a first portion of the input signal with the reflected optical response signal before the first portion of the input signal and the reflected optical response signal are detected by a first receiver and for combining a second portion of the input signal with the optical response signal before the second signal and the optical response signal are detected by a second receiver. The optical component of the test structure may be connected by optical fibers or integrated into a single substrate.
    Type: Application
    Filed: February 20, 2002
    Publication date: August 21, 2003
    Inventors: Tun Sein Tan, Douglas M. Baney
  • Publication number: 20030016425
    Abstract: An optical detection system includes a planar waveguide optical coupler that is directly adjacent to a polarizing beam splitter. The planar waveguide optical coupler combines an input signal with a local oscillator signal and the polarizing beam splitter divides the combined optical signal into orthogonally polarized beams. The orthogonally polarized beams are detected by first and second optical detectors. In one embodiment, the planar waveguide optical coupler is in contact with the polarizing beam splitter, in another embodiment, the planar waveguide optical coupler is attached to the polarizing beam splitter, and in another embodiment, the planar waveguide optical coupler and the polarizing beam splitter are attached to opposite sides of a polarization rotator.
    Type: Application
    Filed: July 19, 2001
    Publication date: January 23, 2003
    Inventors: Tun Sein Tan, Douglas M. Baney, Steven A. Newton
  • Publication number: 20020127751
    Abstract: The extraction efficiency of a light emitting device can be improved by making the absorbing device layers as thin as possible. The internal quantum efficiency decreases as the device layers become thinner. An optimal active layer thickness balances both effects. An AlGaInP LED includes a substrate and device layers including an AlGaInP lower confining layer of a first conductivity type, an AlGaInP active region of a second conductivity type, and an AlGaInP upper confining layer of a second conductivity type. The absorbance of the active region is at least one fifth of the total absorbance in the light-emitting device. The device optionally includes at least one set-back layers of AlGaInP interposing one of confining layer and active region. The p-type upper confining layer may be doped with oxygen improve the reliability.
    Type: Application
    Filed: November 5, 2001
    Publication date: September 12, 2002
    Inventors: Nathan F. Gardner, Fred A. Kish, Herman C. Chui, Stephen A. Stockman, Michael R. Krames, Gloria E. Hofler, Christopher Kocot, Nicolas J. Moll, Tun-Sein Tan
  • Patent number: 6133589
    Abstract: A light-emitting diode (LED) and a method of making the device utilize a thick multi-layered epitaxial structure that increases the light extraction efficiency of the device. The LED is an aluminum-gallium-indium-nitride (AlGaInN)-based LED. The thick multi-layered epitaxial structure increases the light extraction efficiency of the device by increasing the amount of emitted light that escapes the device through the sides of the thick multi-layered epitaxial structure. The LED includes a substrate, a buffer layer, and the thick multi-layered epitaxial structure. In the preferred embodiment, the substrate is a sapphire substrate having a textured surface. The textured surface of the substrate randomized light impinges the textured surface, so that an increased amount of emitted light may escape the LED as output light. The multi-layered epitaxial structure includes an upper AlGaInN region, an active region, and a lower AlGaInN region.
    Type: Grant
    Filed: June 8, 1999
    Date of Patent: October 17, 2000
    Assignee: LumiLeds Lighting, U.S., LLC
    Inventors: Michael Ragan Krames, Paul Scott Martin, Tun Sein Tan
  • Patent number: 6043481
    Abstract: An optoelectronic device and method for making same in which the device demonstrates efficient fill factor and focuses light upon an optoelectronic element close to the focal point of the light focusing element. The device comprises a substrate supporting an optoelectronic element, a microlens array, and a light transmissive layer intermediate between the substrate and the microlens array. The intermediate layer is of a thickness so that the spot size formed by the light collected by the microlens is substantially smaller than the photosensitive or photosensitive area at the plane of the optoelectronic element. In alternate embodiments, the transmissive layer assists in achieving maximum fill factor. The method taught provides minimum alignment steps thereby providing a method of improved manufacturability.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: March 28, 2000
    Assignee: Hewlett-Packard Company
    Inventors: Tun Sein Tan, Ronald Kaneshiro