Patents by Inventor Dean Tsang

Dean Tsang 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: 6798550
    Abstract: A modulator formed with a solid state electro-optic material having a pixellated structure interconnected to a circuit on a semiconductor substrate. Silicon CMOS integrated circuit that can include random access memories (RAMs) are used as a substrate and interfaced to solid state electro-optic materials coated thereon. In particular, the electro-optic modulators are controlled by RAM cells to produce a modulation of reflected light. SRAMs can be used with connection to the SRAM cell flip-flop. DRAMs can be used with the modulator replacing the DRAM storage capacitor. The SLM thus formed can be connected to a digital computer and controlled as if were a being written to as a memory, but other IC structures can also be used. In order to enhance the modulation effects, the electro-optic material is used as the spacer for a Fabry-Perot etalon structure that is also deposited on the semiconductor substrate. PLZT is a suitable electro-optic material.
    Type: Grant
    Filed: November 17, 2000
    Date of Patent: September 28, 2004
    Assignee: Corning Applied Technologies Corporation
    Inventors: Feiling Wang, Kewen Kevin Li, Dean Tsang, Hua Jiang
  • Patent number: 6522456
    Abstract: An apparatus and method for filtering an optical input is disclosed. In an illustrative embodiment, an optical input is split into polarization components along separate paths. The polarization components are then fed into a first electro-optic device that includes a set of electrodes across which a voltage is applied to adjust a wavelength transmission characteristic of the device. A section of the first device positioned between the electrodes preferably has a birefringence that is adjusted depending on the voltage applied across the electrodes. The adjusted components of the optical input are thereafter combined to produce an optical output. Accordingly, the optical input can be attenuated based on the voltage applied to electrodes of the first electro-optic device.
    Type: Grant
    Filed: May 4, 2001
    Date of Patent: February 18, 2003
    Assignees: Corning Applied Technologies, Inc., Corning Incorporated
    Inventors: Qiushui Chen, Hua Jiang, Yingyin Zou, Dean Tsang, Paul Melman, Feiling Wang, Guanghai Jin, Jing Zhao
  • Publication number: 20020163707
    Abstract: An apparatus and method for filtering an optical input is disclosed. In an illustrative embodiment, an optical input is split into polarization components along separate paths. The polarization components are then fed into a first electro-optic device that includes a set of electrodes across which a voltage is applied to adjust a wavelength transmission characteristic of the device. A section of the first device positioned between the electrodes preferably has a birefringence that is adjusted depending on the voltage applied across the electrodes. The adjusted components of the optical input are thereafter combined to produce an optical output. Accordingly, the optical input can be attenuated based on the voltage applied to electrodes of the first electro-optic device.
    Type: Application
    Filed: May 4, 2001
    Publication date: November 7, 2002
    Applicant: Corning Applied Technologies, Inc.
    Inventors: Qiushui Chen, Hua Jiang, Yingyin Zou, Dean Tsang, Paul Melman, Feiling Wang, Guanghai Jin, Jing Zhao
  • Patent number: 6404538
    Abstract: An optical modulator is provided to control the intensity of a transmitted or reflected light. In a transmission mode, a separator splits arbitrarily polarized light into two polarization rays and one is made to travel a separate path from the other. A recombiner causes the two rays to recombine at an output unless an electro-optic phase retarder changes the polarization of the two rays, in which case, both of them miss the output by an amount which is a function of the voltage on the retarder. A normally-off version with low polarization mode dispersion is obtained by changing the orientation of the recombiner. A normally-on version with low polarization mode dispersion is obtained with a passive polarization direction rotator. Similar results can be obtained in a reflection mode where the input and output are on the same side of the modulator. Versions using a GRIN lens are particularly suited to modulation of light out of and back into fiber-optic cables.
    Type: Grant
    Filed: October 24, 2000
    Date of Patent: June 11, 2002
    Assignee: Corning Applied Technologies Corporation
    Inventors: Qiushui Chen, Gary Y. Wang, Paul Melman, Kevin Zou, Hua Jiang, Run Zhang, Jing Zhao, Dean Tsang, Feiling Wang
  • Patent number: 6330097
    Abstract: An optical modulator is provided to control the intensity of a transmitted or reflected light. In a transmission mode, a separator splits arbitrarily polarized light into two polarization rays and one is made to travel a separate path from the other. A recombiner causes the two rays to recombine at an output unless an electro-optic phase retarder changes the polarization of the two rays, in which case, both of them miss the output by an amount which is a function of the voltage on the retarder. A normally-off version with low polarization mode dispersion is obtained by changing the orientation of the recombiner. A normally-on version with low polarization mode dispersion is obtained with a passive polarization direction rotator. Similar results can be obtained in a reflection mode where the input and output are on the same side of the modulator. Versions using a GRIN lens are particularly suited to modulation of light out of and back into fiber-optic cables.
    Type: Grant
    Filed: April 8, 1999
    Date of Patent: December 11, 2001
    Assignee: Corning Applied Technologies Corp.
    Inventors: Qiushui Chen, Gary Y. Wang, Paul Melman, Kevin Zou, Hua Jiang, Run Zhang, Jing Zhao, Dean Tsang, Feiling Wang