Patents by Inventor Chuni Ghosh

Chuni Ghosh 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: 20200127441
    Abstract: A proximity sensor which uses very narrow divergent beams from Vertical Cavity Surface Emitting Laser (VCSEL) for the illumination source is disclosed. Narrow divergent beams in the range 0.5 to 10 degrees can be achieved to provide high proximity sensing accuracy in a small footprint assembly. One approach to reducing the beam divergence is to increase the length of the VCSEL resonant cavity using external third mirror. A second embodiment extends the length of the VCSEL cavity by modifying the DBR mirrors and the gain region. Optical microlenses can be coupled with the VCSEL to collimate the output beam and reduce the beam divergence. These can be separate optical elements or integrated with the VCEL by modifying the substrate output surface profile or an added a transparent layer. These methods of beam divergence reduction are incorporated into various embodiment configurations to produce a miniature proximity sensor suitable for cell phones and tablets.
    Type: Application
    Filed: December 28, 2017
    Publication date: April 23, 2020
    Inventors: Chuni Ghosh, Jean-Francois Seurin
  • Patent number: 10353215
    Abstract: A coded pattern projector apparatus comprises a surface-emitting array of emitters comprising a plurality of emitters where each of the plurality of emitters generates one of a plurality of optical beams in response to an electrical drive signal applied to a respective electrical input of each of the plurality of emitters. A first optical element projects each the plurality of optical beams generated by the surface-emitting array of emitters. A second optical element collimates the plurality of optical beams in a first dimension and diverges the plurality of optical beams in a second dimension such that the plurality of optical beams form at least one stripe patterns. A controller has electrical outputs, each of the electrical outputs is connected to a respective electrical input of each of the plurality of emitters. The controller generates electrical drive signals that produce a coded stripe pattern.
    Type: Grant
    Filed: March 13, 2018
    Date of Patent: July 16, 2019
    Assignee: Princeton Optronics, Inc.
    Inventors: Tong Chen, Chuni Ghosh, Laurence Watkins
  • Patent number: 10290993
    Abstract: A VCSEL illuminator module includes a module forming a physical cavity having electrical contacts positioned on an inner surface of the module that feed through the module to electrical contacts positioned on an outer surface of the module. A VCSEL device is positioned on the inner surface module and includes electrical contacts that are electrically connected to the electrical contacts on the inner surface of the module. The VCSEL device generates an optical beam when current is applied to the electrical contacts. An optical element is positioned adjacent to an emitting surface of the VCSEL device and is configured to modify the optical beam generated by the VCSEL device.
    Type: Grant
    Filed: May 25, 2017
    Date of Patent: May 14, 2019
    Assignee: Princeton Optronics, Inc.
    Inventors: Tong Chen, Chuni Ghosh, Qing Wang, Alexey Kovsh, Laurence Watkins
  • Publication number: 20190067909
    Abstract: A Vertical Cavity Surface Emitting Laser (VCSEL) includes a reflecting surface of the VCSEL. A gain region is positioned on the distributed Bragg reflector that generates optical gain. The gain region comprises a first and second multiple quantum well stack, a tunnel junction positioned between the first and second multiple quantum well stack, and a current aperture positioned on one of the first and second multiple quantum well stack. The current aperture confines a current flow in the gain region. A partially reflective surface and the reflective surface forming a VCSEL resonant cavity, wherein an output optical beam propagates from the partially reflecting surface.
    Type: Application
    Filed: August 2, 2018
    Publication date: February 28, 2019
    Applicant: Princeton Optronics, Inc.
    Inventors: Chuni Ghosh, Jean-Francois Seurin, Delai Zhou, Laurence Watkins
  • Publication number: 20180203247
    Abstract: A coded pattern projector apparatus comprises a surface-emitting array of emitters comprising a plurality of emitters where each of the plurality of emitters generates one of a plurality of optical beams in response to an electrical drive signal applied to a respective electrical input of each of the plurality of emitters. A first optical element projects each the plurality of optical beams generated by the surface-emitting array of emitters. A second optical element collimates the plurality of optical beams in a first dimension and diverges the plurality of optical beams in a second dimension such that the plurality of optical beams form at least one stripe patterns. A controller has electrical outputs, each of the electrical outputs is connected to a respective electrical input of each of the plurality of emitters. The controller generates electrical drive signals that produce a coded stripe pattern.
    Type: Application
    Filed: March 13, 2018
    Publication date: July 19, 2018
    Applicant: Princeton Optronics, Inc.
    Inventors: Tong Chen, Chuni Ghosh, Laurence Watkins
  • Patent number: 9946089
    Abstract: A coded pattern projector apparatus comprises a surface-emitting array of emitters comprising a plurality of emitters where each of the plurality of emitters generates one of a plurality of optical beams in response to an electrical drive signal applied to a respective electrical input of each of the plurality of emitters. A first optical element projects each the plurality of optical beams generated by the surface-emitting array of emitters. A second optical element collimates the plurality of optical beams in a first dimension and diverges the plurality of optical beams in a second dimension such that the plurality of optical beams form at least one stripe patterns. A controller has electrical outputs, each of the electrical outputs is connected to a respective electrical input of each of the plurality of emitters. The controller generates electrical drive signals that produce a coded stripe pattern.
    Type: Grant
    Filed: October 7, 2016
    Date of Patent: April 17, 2018
    Assignee: Princeton Optronics, Inc.
    Inventors: Tong Chen, Chuni Ghosh, Laurence Watkins
  • Publication number: 20170353004
    Abstract: A VCSEL illuminator module includes a module forming a physical cavity having electrical contacts positioned on an inner surface of the module that feed through the module to electrical contacts positioned on an outer surface of the module. A VCSEL device is positioned on the inner surface module and includes electrical contacts that are electrically connected to the electrical contacts on the inner surface of the module. The VCSEL device generates an optical beam when current is applied to the electrical contacts. An optical element is positioned adjacent to an emitting surface of the VCSEL device and is configured to modify the optical beam generated by the VCSEL device.
    Type: Application
    Filed: May 25, 2017
    Publication date: December 7, 2017
    Applicant: Princeton Optronics, Inc.
    Inventors: Tong Chen, Chuni Ghosh, Qing Wang, Alexey Kovsh, Laurence Watkins
  • Publication number: 20170256915
    Abstract: A Vertical Cavity Surface Emitting Laser (VCSEL) includes a reflecting surface of the VCSEL. A gain region is positioned on the distributed Bragg reflector that generates optical gain. The gain region comprises a first and second multiple quantum well stack, a tunnel junction positioned between the first and second multiple quantum well stack, and a current aperture positioned on one of the first and second multiple quantum well stack. The current aperture confines a current flow in the gain region. A partially reflective surface and the reflective surface forming a VCSEL resonant cavity, wherein an output optical beam propagates from the partially reflecting surface.
    Type: Application
    Filed: March 2, 2017
    Publication date: September 7, 2017
    Applicant: Princeton Optronics, Inc.
    Inventors: Chuni Ghosh, Jean-Francois Seurin, Delai Zhou, Laurence Watkins
  • Publication number: 20170115497
    Abstract: A coded pattern projector apparatus comprises a surface-emitting array of emitters comprising a plurality of emitters where each of the plurality of emitters generates one of a plurality of optical beams in response to an electrical drive signal applied to a respective electrical input of each of the plurality of emitters. A first optical element projects each the plurality of optical beams generated by the surface-emitting array of emitters. A second optical element collimates the plurality of optical beams in a first dimension and diverges the plurality of optical beams in a second dimension such that the plurality of optical beams form at least one stripe patterns. A controller has a plurality of electrical outputs, each of the plurality of electrical outputs is connected to a respective electrical inputs of each of the plurality of emitters. The controller generating desired electrical drive signals that produce a desired coded stripe pattern.
    Type: Application
    Filed: October 7, 2016
    Publication date: April 27, 2017
    Applicant: Princeton Optronics, Inc.
    Inventors: Tong Chen, Chuni Ghosh, Laurence Watkins
  • Publication number: 20130266032
    Abstract: Disclosed herein are architectures for an external cavity laser. In some embodiments, the external cavity laser includes vertical cavity surface emitting laser (VCSEL) elements, a Brewster plate, frequency doubling chips, and a microlens array. The Brewster plate is arranged at an angle relative to the light path, and is configured to polarize at least the light received from the VCSELs and propagating on the light path in a first direction, and extract, from the external cavity, frequency-doubled light propagating on the light path in a second direction opposite to the first direction. The doubling chips are operable to receive the light and double the frequency of a portion of the received light. The microlens array is aligned with the VCSEL elements. A mount may be employed to mount the side stack of doubling chips by either side mounting or end mounting.
    Type: Application
    Filed: April 5, 2013
    Publication date: October 10, 2013
    Applicant: RealD Inc.
    Inventors: Robert Van Leeuwen, Bing XU, Qing Wang, Chuni Ghosh
  • Publication number: 20070231669
    Abstract: An electrochemical fuel cell designed for a large electrochemical reaction surface area per unit volume for high power density and high efficiency. The fuel cell is designed for counter propagating reactants flow for uniform reaction rate over the whole reaction area. This design is scalable and a single cell can be built with output power level ranging from a few watts to several megawatts. The cell does not require bipolar plates and is lightweight. The design has been demonstrated with proton exchange membrane as an electrolyte for the electrochemical reaction, however, the design is adaptable for other types of fuels and fuel cells with other electrolytes including all types of polymer electrolytic fuel cells, alkaline fuel cells, phosphoric acid fuel cells, molten carbonate fuel cells, solid oxide fuel cells and all their subcategories as well. The fuel cell is adaptable for use as an electrolyzer as well.
    Type: Application
    Filed: March 22, 2007
    Publication date: October 4, 2007
    Inventor: Chuni Ghosh
  • Patent number: 7065112
    Abstract: A wavelength locker comprising a semiconductor or air gap etalon is used to monitor and maintain the output wavelength of a coherent radiation source. Said etalon may be fabricated from a commercially available silicon wafer, with individual regions of the wafer, each functioning as a separate etalon, etched or otherwise processed to produce different thicknesses. Illumination by the coherent radiation source generated transmitted signal intensities that are detected and processed to determine the output wavelength of the coherent radiation source. A wavelength tuner is then used to maintain or vary the output wavelength based on continuous measurements of etalon signal intensity.
    Type: Grant
    Filed: May 12, 2003
    Date of Patent: June 20, 2006
    Assignee: Princeton Optronics, Inc.
    Inventors: Chuni Ghosh, Laurence S. Watkins, Qing Wang, Raymond William Simpson, Steven R Leffler
  • Publication number: 20050025211
    Abstract: A vertical cavity surface emitting laser (VCSEL) device with improved power and beam characteristics. The VCSEL device contains one VCSEL or an array of VCSELs. Each VCSEL has a corresponding integrated microlens, and a heat sink is attached to the device side of the VCSEL device. The heat sink allows improved heat dissipation, and therefore provides improved power characteristics of the VCSEL device output laser beam. The microlens or microlens array allows easier and more compact focussing of the VCSEL device output laser beam. The VCSEL device can be used in a variety of optical systems, and its improved power and focusing characteristics provide a compact, low power, low cost laser system.
    Type: Application
    Filed: August 23, 2004
    Publication date: February 3, 2005
    Applicant: PRINCETON OPTRONICS, INC.
    Inventors: Kaiyan Zhang, Jiamin Zhang, Chuni Ghosh, Laurence Watkins
  • Publication number: 20040228375
    Abstract: A wavelength locker comprising a semiconductor or air gap etalon is used to monitor and maintain the output wavelength of a coherent radiation source. Said etalon may be fabricated from a commercially available silicon wafer, with individual regions of the wafer, each functioning as a separate etalon, etched or otherwise processed to produce different thicknesses. Illumination by the coherent radiation source generated transmitted signal intensities that are detected and processed to determine the output wavelength of the coherent radiation source. A wavelength tuner is then used to maintain or vary the output wavelength based on continuous measurements of etalon signal intensity.
    Type: Application
    Filed: May 12, 2003
    Publication date: November 18, 2004
    Applicant: Princeton Optronics, Inc.
    Inventors: Chuni Ghosh, Laurence S. Watkins, Qing Wang, Raymond William Simpson, Steven R. Leffler