Patents by Inventor Chuni L. Ghosh

Chuni L. 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).

  • Patent number: 9574541
    Abstract: A high efficiency optical ignition device is provided in a two-part compact and robust package to be mounted directly on an internal combustion engine chamber. The ignition device ignites a combustion fuel with a high intensity plasma generated by a high power laser beam from a solid state laser operable in Q-switched, or non-Q-switched mode for producing short or long pulses, respectively. Multiple pulses are generated, and duration and frequency of the laser beam pulses are controlled by controlling an optical pump module to pump the solid state laser. The optical pump module comprises a semiconductor laser, preferably a VCSEL device. One or more laser beams are precisely directed, each one to a desired location anywhere within the combustion chamber for more efficient and near complete burning of the combustion fuel. The robust packaging is well suited to withstand mechanical and thermal stresses of the internal combustion engine.
    Type: Grant
    Filed: May 27, 2016
    Date of Patent: February 21, 2017
    Assignee: PRINCETON OPTRONICS INC.
    Inventors: Chuni L Ghosh, Qing Wang, Bing Xu, Robert van Leeuwen
  • Patent number: 9553423
    Abstract: A miniature structured light illuminator is provided. The miniature structured light illuminator uses a semiconductor surface emitting array including VCSEL or RC-LED array and an array of microlens elements to generate a wide range of structured light illumination patterns. The emission beam from a surface emitter array may be selectively directed, steered, focused or expanded, by applying a lateral displacement of the microlens array, such that centers of the emission beam and microlens array are misaligned. Emitted beams may be directed through small optical components to project the structured light pattern to a distant plane. The surface emitting arrays may be configured in addressable form to be activated separately for continuous or pulsed operation with very fast pulses having <100 ps risetime. A compact structured light illuminator module with projection optics is provided in very small physical size (˜6×6×3 mm3) suitable to configure in a handheld device.
    Type: Grant
    Filed: February 27, 2016
    Date of Patent: January 24, 2017
    Assignee: PRINCETON OPTRONICS INC.
    Inventors: Tong Chen, Chuni L Ghosh, Jean-Francois Seurin, Laurence S Watkins
  • Patent number: 9520696
    Abstract: A set of VCSEL fabrication methods has been invented which enhance the performance and long time reliability of VCSEL devices and arrays of devices. Wafer bow caused by growing a large number of epitaxial layers required to fabricate VCSEL device generates strain and results in bowing/warping of the device wafer. The stress so generated is eliminated by applying a stress compensation layer on the substrate to a surface opposite to the epitaxial layer surface. New oxidation equipment designs and process parameters are described which produce more precision apertures and reduce stress in the VCSEL device. An ultrathin fabrication procedure is described which enables high power VCSELs to be made for high power operation at many different wavelengths. A low temperature electrical contacting process improves VCSEL long term reliability.
    Type: Grant
    Filed: March 2, 2015
    Date of Patent: December 13, 2016
    Assignee: PRINCETON OPTRONICS INC.
    Inventors: Qing Wang, Jean-Francois Seurin, Chuni L Ghosh, Laurence S Watkins
  • Publication number: 20160348636
    Abstract: A high efficiency optical ignition device is provided in a two-part compact and robust package to be mounted directly on an internal combustion engine chamber. The ignition device ignites a combustion fuel with a high intensity plasma generated by a high power laser beam from a solid state laser operable in Q-switched, or non-Q-switched mode for producing short or long pulses, respectively. Multiple pulses are generated, and duration and frequency of the laser beam pulses are controlled by controlling an optical pump module to pump the solid state laser. The optical pump module comprises a semiconductor laser, preferably a VCSEL device. One or more laser beams are precisely directed, each one to a desired location anywhere within the combustion chamber for more efficient and near complete burning of the combustion fuel. The robust packaging is well suited to withstand mechanical and thermal stresses of the internal combustion engine.
    Type: Application
    Filed: May 27, 2016
    Publication date: December 1, 2016
    Applicant: Princeton Optronics Inc.
    Inventors: Chuni L. Ghosh, Qing Wang, Bing Xu, Robert van Leeuwen
  • Publication number: 20160254638
    Abstract: A miniature structured light illuminator is provided. The miniature structured light illuminator uses a semiconductor surface emitting array including VCSEL or RC-LED array and an array of microlens elements to generate a wide range of structured light illumination patterns. The emission beam from a surface emitter array may be selectively directed, steered, focused or expanded, by applying a lateral displacement of the microlens array, such that centers of the emission beam and microlens array are misaligned. Emitted beams may be directed through small optical components to project the structured light pattern to a distant plane. The surface emitting arrays may be configured in addressable form to be activated separately for continuous or pulsed operation with very fast pulses having <100 ps risetime. A compact structured light illuminator module with projection optics is provided in very small physical size (˜6×6×3 mm3) suitable to configure in a handheld device.
    Type: Application
    Filed: February 27, 2016
    Publication date: September 1, 2016
    Applicant: Princeton Optronics Inc.
    Inventors: Tong Chen, Chuni L. Ghosh, Jean-Francois Seurin, Laurence S. Watkins
  • Publication number: 20160072258
    Abstract: A structured light source comprising VCSEL arrays is configured in many different ways to project a structured illumination pattern into a region for 3 dimensional imaging and gesture recognition applications. One aspect of the invention describes methods to construct densely and ultra-densely packed VCSEL arrays with to produce high resolution structured illumination pattern. VCSEL arrays configured in many different regular and non-regular arrays together with techniques for producing addressable structured light source are extremely suited for generating structured illumination patterns in a programmed manner to combine steady state and time-dependent detection and imaging for better accuracy. Structured illumination patterns can be generated in customized shapes by incorporating differently shaped current confining apertures in VCSEL devices.
    Type: Application
    Filed: September 9, 2015
    Publication date: March 10, 2016
    Applicant: PRINCETON OPTRONICS INC.
    Inventors: Jean-Francois Seurin, Chuni L. Ghosh, Tong Chen, Laurence S. Watkins
  • Publication number: 20150311673
    Abstract: A new VCSEL design is presented to achieve high output power and high brightness with a strong selection of a linear polarization state in high speed pulsing operation. Higher output power is achieved by including multiple gain segments in tandem, in the gain region. To achieve single mode operation with high output power, an extended cavity three reflector design is presented. High degree of polarization selectivity is achieved by a linear grating deployed with the third reflector, such that lasing is allowed only in a preferred linear polarization state. A polarization selective reflector including a linear grating is designed to impart strong polarization selectivity for a preferred linear polarization state. The polarization selective reflector used as the third reflector in an extended cavity VCSEL device, exhibits strong polarization selection for a preferred linear polarization state during high speed pulsing including in the gain switching resonance regime.
    Type: Application
    Filed: April 29, 2015
    Publication date: October 29, 2015
    Applicant: Princeton Optronics Inc.
    Inventors: Qing Wang, Jean-Francois Seurin, Chuni L Ghosh, Laurence S Watkins
  • Publication number: 20150255955
    Abstract: A set of VCSEL fabrication methods has been invented which enhance the performance and long time reliability of VCSEL devices and arrays of devices. Wafer bow caused by growing a large number of epitaxial layers required to fabricate VCSEL device generates strain and results in bowing/warping of the device wafer. The stress so generated is eliminated by applying a stress compensation layer on the substrate to a surface opposite to the epitaxial layer surface. New oxidation equipment designs and process parameters are described which produce more precision apertures and reduce stress in the VCSEL device. An ultrathin fabrication procedure is described which enables high power VCSELs to be made for high power operation at many different wavelengths. A low temperature electrical contacting process improves VCSEL long term reliability.
    Type: Application
    Filed: March 2, 2015
    Publication date: September 10, 2015
    Applicant: Princeton Optronics Inc.
    Inventors: Qing Wang, Jean-Francois Seurin, Chuni L. Ghosh, Laurence S. Watkins
  • Publication number: 20140218898
    Abstract: VCSEL arrays with planar electrical contacts readily adaptable for surface mounting are provided. Monolithic VCSEL arrays are configured in array patterns on two and three-dimensional surfaces for configuring optical illuminator modules. Illuminator modules are easily expandable by increasing the array size or by modularly arranging more arrays with or without a transparent substrate, in different shapes by tiling array modules monolithically on a common substrate, or by tiling small modules. The surface mountable illuminator modules are easily assembled on a thermally conductive surface that may be air or liquid cooled for efficient heat dissipation. Array modules may be integrated with other electronic circuits such as current drivers, sensors, controllers, processors, etc.
    Type: Application
    Filed: January 28, 2014
    Publication date: August 7, 2014
    Applicant: Princeton Optronics Inc.
    Inventors: Jean F. Seurin, Chuni L. Ghosh, Qing Wang, Laurence S. Watkins
  • Patent number: 8783893
    Abstract: VCSEL arrays with planar electrical contacts readily adaptable for surface mounting are provided. Monolithic VCSEL arrays are configured in array patterns on two and three-dimensional surfaces for configuring optical illuminator modules. Illuminator modules are easily expandable by increasing the array size or by modularly arranging more arrays with or without a transparent substrate, in different shapes by tiling array modules monolithically on a common substrate, or by tiling small modules. The surface mountable illuminator modules are easily assembled on a thermally conductive surface that may be air or liquid cooled for efficient heat dissipation. Array modules may be integrated with other electronic circuits such as current drivers, sensors, controllers, processors, etc.
    Type: Grant
    Filed: January 28, 2014
    Date of Patent: July 22, 2014
    Inventors: Jean F. Seurin, Chuni L Ghosh, Qing Wang, Laurence S. Watkins
  • Publication number: 20140139467
    Abstract: Touch screen sensor systems that incorporate VCSELs or VCSEL arrays to provide illumination beams for sensing the position of objects such as a finger or stylus in a two dimensional space is provided. Normally the touch sensor is used with a display screen so that objects in the display screen are identified by positioning a finger or stylus at the object's position. The invention describes improved illumination methods using VCSELs that realize higher resolution in position sensing. VCSELs can also be integrated with detectors on a common substrate which provides both illumination and detection functions for the touch sensor system. Different methods to suitably couple light from VCSEL arrays directly, or through guided light paths such as fibers and waveguide arrays are provided to configure a touch sensor in different applications.
    Type: Application
    Filed: November 20, 2013
    Publication date: May 22, 2014
    Applicant: Princeton Optronics Inc.
    Inventors: Chuni L. Ghosh, Jean-Francois Seurin, Laurence S. Watkins
  • Patent number: 8675706
    Abstract: Illuminator module comprising VCSEL arrays with planar electrical contacts, readily adaptable for surface mounting, is provided. Monolithic VCSEL arrays are configured in array patterns on two and three-dimensional surfaces. Illuminator modules are easily expandable by increasing the array size or by modularly arranging more arrays with or without a transparent substrate. Different shapes of illuminator modules may be configured by tiling array modules monolithically on a common substrate, or by tiling small modules. The surface mountable illuminator modules are easily assembled on a thermally conductive surface that may be air or liquid cooled for efficient heat dissipation. Array modules may be integrated with other electronic circuits such as current drivers, sensors, controllers, processors, etc.
    Type: Grant
    Filed: July 5, 2012
    Date of Patent: March 18, 2014
    Assignee: Princeton Optronics Inc.
    Inventors: Jean F Seurin, Chuni L Ghosh, Qing Wang, Laurence Watkins
  • Patent number: 8576885
    Abstract: Optical pump modules using VCSEL arrays are provided to pump optical gain media for achieving high power laser output in CW, QCW and pulse operation modes for operation. Low divergence and symmetric far-field emission from VCSELs are particularly suitable for compact arrays. VCSEL arrays configured as laser pump modules are operable at high temperatures with practically no degradation over a long period of time. VCSEL pump modules are adaptable for side- or end-pumping configurations to pump high power lasers in CW, QCW and pulse mode. Power output from VCSEL pump modules is scalable. Incorporating microlens arrays with the VCSEL arrays improve brightness of the pump modules. High power and high temperature operation of VCSEL modules make it suitable for making compact high power solid state lasers that are operable in small spaces such as, ignition of internal combustion engines, stationary power generation engines and pulsed detonation engines.
    Type: Grant
    Filed: February 9, 2012
    Date of Patent: November 5, 2013
    Assignee: Princeton Optronics, Inc.
    Inventors: Robert van Leeuwen, Yihan Xiong, Jean F Seurin, Chuni L Ghosh, Bing Xu
  • Publication number: 20130163627
    Abstract: An optical illuminator using Vertical Cavity Surface Emitting Laser (VCSEL) is disclosed. Optical modules configured using single VCSEL and VCSEL arrays bonded to a thermal submount to conduct heat away from the VCSEL array, are suited for high power and high speed operation. High speed optical modules are configured using single VCSEL or VCSEL arrays connected to a high speed electronic module on a common thermal submount or on a common Printed Circuit Board (PCB) platform including transmission lines. The electronic module provides low inductance current drive and control functions to operate the VCSEL and VCSEL array. VCSEL apertures are designed for a desired beam shape. Additional beam shaping elements are provided for VCSELs or VCSEL arrays, for desired output beam shapes and/or emission patterns. VCSEL arrays may be operated in continuous wave (CW) or pulse operation modes in a programmable fashion using a built-in or an external controller.
    Type: Application
    Filed: December 24, 2011
    Publication date: June 27, 2013
    Applicant: PRINCETON OPTRONICS
    Inventors: Jean F. Seurin, Chuni L. Ghosh, Qing Wang
  • Patent number: 6888871
    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: Grant
    Filed: July 12, 2000
    Date of Patent: May 3, 2005
    Assignee: Princeton Optronics, Inc.
    Inventors: Kaiyan Zhang, Jiamin Zhang, Chuni L. Ghosh, Laurence S. Watkins
  • Patent number: 4525448
    Abstract: A method of fabricating a very small-size gate on a semiconductor substrate includes covering the substrate with a photoresist layer, masking an area of the photoresist layer that has a size exceeding the desired size of the gate, subjecting the photoresist layer to overexposure so that the size of the unaffected area is reduced to the desired size, removing the overexposed region of the photoresist layer, providing a protective coating on such region, clearing the unaffected photoresist material out of the area occupied thereby, and depositing gate material at least in the thus obtained recess. The gate material may be deposited over the protective coating, in which case the zone at which the gate is to remain is protected by unexposed photoresist material and the remainder of the gate material is removed from the protective coating.
    Type: Grant
    Filed: January 6, 1984
    Date of Patent: June 25, 1985
    Assignee: International Telephone and Telegraph Corporation
    Inventor: Chuni L. Ghosh