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).
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Publication number: 20200127441Abstract: 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: ApplicationFiled: December 28, 2017Publication date: April 23, 2020Inventors: Chuni Ghosh, Jean-Francois Seurin
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Patent number: 10353215Abstract: 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: GrantFiled: March 13, 2018Date of Patent: July 16, 2019Assignee: Princeton Optronics, Inc.Inventors: Tong Chen, Chuni Ghosh, Laurence Watkins
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Patent number: 10290993Abstract: 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: GrantFiled: May 25, 2017Date of Patent: May 14, 2019Assignee: Princeton Optronics, Inc.Inventors: Tong Chen, Chuni Ghosh, Qing Wang, Alexey Kovsh, Laurence Watkins
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Publication number: 20190067909Abstract: 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: ApplicationFiled: August 2, 2018Publication date: February 28, 2019Applicant: Princeton Optronics, Inc.Inventors: Chuni Ghosh, Jean-Francois Seurin, Delai Zhou, Laurence Watkins
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Publication number: 20180203247Abstract: 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: ApplicationFiled: March 13, 2018Publication date: July 19, 2018Applicant: Princeton Optronics, Inc.Inventors: Tong Chen, Chuni Ghosh, Laurence Watkins
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Patent number: 9946089Abstract: 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: GrantFiled: October 7, 2016Date of Patent: April 17, 2018Assignee: Princeton Optronics, Inc.Inventors: Tong Chen, Chuni Ghosh, Laurence Watkins
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Publication number: 20170353004Abstract: 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: ApplicationFiled: May 25, 2017Publication date: December 7, 2017Applicant: Princeton Optronics, Inc.Inventors: Tong Chen, Chuni Ghosh, Qing Wang, Alexey Kovsh, Laurence Watkins
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Publication number: 20170256915Abstract: 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: ApplicationFiled: March 2, 2017Publication date: September 7, 2017Applicant: Princeton Optronics, Inc.Inventors: Chuni Ghosh, Jean-Francois Seurin, Delai Zhou, Laurence Watkins
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Publication number: 20170115497Abstract: 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: ApplicationFiled: October 7, 2016Publication date: April 27, 2017Applicant: Princeton Optronics, Inc.Inventors: Tong Chen, Chuni Ghosh, Laurence Watkins
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Publication number: 20130266032Abstract: 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: ApplicationFiled: April 5, 2013Publication date: October 10, 2013Applicant: RealD Inc.Inventors: Robert Van Leeuwen, Bing XU, Qing Wang, Chuni Ghosh
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Publication number: 20070231669Abstract: 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: ApplicationFiled: March 22, 2007Publication date: October 4, 2007Inventor: Chuni Ghosh
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Patent number: 7065112Abstract: 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: GrantFiled: May 12, 2003Date of Patent: June 20, 2006Assignee: Princeton Optronics, Inc.Inventors: Chuni Ghosh, Laurence S. Watkins, Qing Wang, Raymond William Simpson, Steven R Leffler
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Publication number: 20050025211Abstract: 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: ApplicationFiled: August 23, 2004Publication date: February 3, 2005Applicant: PRINCETON OPTRONICS, INC.Inventors: Kaiyan Zhang, Jiamin Zhang, Chuni Ghosh, Laurence Watkins
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Publication number: 20040228375Abstract: 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: ApplicationFiled: May 12, 2003Publication date: November 18, 2004Applicant: Princeton Optronics, Inc.Inventors: Chuni Ghosh, Laurence S. Watkins, Qing Wang, Raymond William Simpson, Steven R. Leffler