Chuni L Ghosh

US Patent:

6888871, May 3, 2005

Filed:

Jul 12, 2000

Appl. No.:

09/615065

Inventors:

Kaiyan Zhang - Belle Meade NJ, US
Jiamin Zhang - Plainsboro NJ, US
Chuni L. Ghosh - West Windsor NJ, US
Laurence S. Watkins - Pennington NJ, US

Assignee:

Princeton Optronics, Inc. - Mercerville NJ

International Classification:

H01S003/091
H01S003/094
H01S003/04

US Classification:

372 75, 372 36, 372 69, 372 70

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.

US Patent:

7065112, Jun 20, 2006

Filed:

May 12, 2003

Appl. No.:

10/435197

Inventors:

Chuni Ghosh - West Windsor NJ, US
Laurence S. Watkins - Pennington NJ, US
Qing Wang - Plainsboro NJ, US
Raymond William Simpson - Hamilton Square NJ, US
Steven R Leffler - Lawrenceville NJ, US

Assignee:

Princeton Optronics, Inc. - Mercerville NJ

International Classification:

H01S 3/13
H01S 3/10

US Classification:

372 32, 372 20

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.

US Patent:

8576885, Nov 5, 2013

Filed:

Feb 9, 2012

Appl. No.:

13/369581

Inventors:

Robert van Leeuwen - Ewing NJ, US
Yihan Xiong - Pennington NJ, US
Jean F Seurin - Princeton Junction NJ, US
Chuni L Ghosh - West Windsor NJ, US
Bing Xu - Bayside NY, US

Assignee:

Princeton Optronics, Inc. - Mercerville NJ

International Classification:

H01S 3/04

US Classification:

372 34, 372 36, 372 3805, 372 5012, 372 50124, 372 72

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.

US Patent:

20050025211, Feb 3, 2005

Filed:

Aug 23, 2004

Appl. No.:

10/922920

Inventors:

Kaiyan Zhang - Belle Meade NJ, US
Jiamin Zhang - Plainsboro NJ, US
Chuni Ghosh - West Windsor NJ, US
Laurence Watkins - Pennington NJ, US

Assignee:

PRINCETON OPTRONICS, INC. - Mercerville NJ

International Classification:

H01S003/08
H01S003/04

US Classification:

372101000, 372036000

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.

US Patent:

20070231669, Oct 4, 2007

Filed:

Mar 22, 2007

Appl. No.:

11/726650

Inventors:

Chuni Ghosh - Princeton Junction NJ, US

International Classification:

H01M 8/02
H01M 8/10
H01M 8/04
C25B 9/00

US Classification:

429038000, 429035000, 429030000, 429026000, 204266000

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.

US Patent:

20130163626, Jun 27, 2013

Filed:

Jul 5, 2012

Appl. No.:

13/541906

Inventors:

J-F Seurin - Princeton Junction NJ, US
Chuni Lal Ghosh - West Windsor NJ, US
Qing Wang - Plainsboro NJ, US
Laurence Watkins - Pennington NJ, US

Assignee:

PRINCETON OPTRONICS - Mercerville NJ

International Classification:

H01S 5/183
H01S 5/024

US Classification:

372 35, 372 50124, 372 36

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. on a common platform, for example, a single or multiple layer printed circuit boards (PCB) to assemble illumination systems for different applications including a gesture recognition apparatus and a battery operated portable illuminator devices.

US Patent:

20130163627, Jun 27, 2013

Filed:

Dec 24, 2011

Appl. No.:

13/337098

Inventors:

Jean F. Seurin - Princeton Junction NJ, US
Chuni L. Ghosh - West Windsor NJ, US
Qing Wang - Plainsboro NJ, US

Assignee:

PRINCETON OPTRONICS - Mercerville NJ

International Classification:

H01S 3/04
H01S 3/00
H01S 5/183
H01S 5/42

US Classification:

372 36, 372 50124, 372 3802

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.

US Patent:

20130208741, Aug 15, 2013

Filed:

Feb 11, 2013

Appl. No.:

13/764770

Inventors:

REALD INC. - , US
Bing XU - Bayside NY, US
Yihan Xiong - Lawrenceville NJ, US
Jean-Francois Seurin - West Windsor, NJ, US
Chuni Ghosh - West Windsor NJ, US

Assignee:

REALD INC. - Beverly Hills CA

International Classification:

H01S 5/06

US Classification:

372 22

Abstract:

Disclosed herein are architectures for VCSEL systems. By using high power IR VCSEL element(s), a bulk doubling material can be used to double the IR light and generate visible light (red, green, blue, or UV light) in a cavity, in either continuous wave (CW) or pulsed mode. The reflectivity of the output distributed Bragg reflector (DBR) of these VCSELs can be designed to increase the power in the cavity, rather than the power in the VCSEL laser. By enabling the use of a bulk doubling material in the cavity and directly doubling the VCSEL the device can be inexpensive, simpler, high efficiency, better reliability, and vastly improved manufacturing and alignment tolerances. There are a number of cavity architectures that can be used to double the IR light from the VCSEL(s). The VCSEL(s) can be single elements, or arrays with high intensity elements.