Gopal M Vasudevan from 1068 Roy Ave, San Jose, CA 95125, age 61, Phone: 4087232307

Us Patents

Amplitude And Phase Controlled Adaptive Optics System
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US Patent:

7397018, Jul 8, 2008
Filed:

Mar 2, 2005
Appl. No.:

11/068754
Inventors:

Ich V. Pham - San Jose CA, US
Gopal Vasudevan - San Jose CA, US
Assignee:

Lockheed Martin Corporation - Bethesda MD
International Classification:

G01J 1/20
US Classification:

2502019, 398118, 398119, 398192, 398201, 359279, 359284, 359286, 359289, 359290, 359291, 359298, 359300, 359318, 2502011, 2502012, 250205
Abstract:

An adaptive optics system is provided. The system includes a light source, a pair of deformable mirrors and a detection module. The light source is configured to provide an outgoing beam. The outgoing beam has an amplitude and a phase. The first deformable mirror is configured to reflect the outgoing beam and adjust its associated amplitude. The second deformable mirror is configured to reflect the outgoing beam reflected from the first deformable mirror and adjust its associated phase. The detection module is configured to detect an incoming beam and the reflected outgoing beam from the second deformable mirror and generate certain signals. The signals are used to control the first and second deformable mirrors such that the amplitude of the outgoing beam is the same as that of the incoming beam and the phase of the outgoing beam is opposite that of the incoming beam.

Extracting Higher Order Information From Scene-Based Shack-Hartmann Wave-Front Sensing
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US Patent:

7617060, Nov 10, 2009
Filed:

Jul 26, 2007
Appl. No.:

11/829061
Inventors:

Herbert E. Rauch - Los Altos CA, US
Dragos B. Maciuca - Mountain View CA, US
Gopal Vasudevan - San Jose CA, US
Assignee:

Lockheed Martin Corporation - Bethesda MD
International Classification:

G06F 19/00
US Classification:

702 85, 356124, 3561245, 359554, 382100, 382254, 702105
Abstract:

An adaptive optics system is provided, comprising a deformable mirror configured to receive an input beam with an aberrated wavefront and to reflect the input beam to a Shack-Hartmann wavefront sensor array. The system further comprises the Shack-Hartmann wavefront sensor array configured to receive the input beam from the deformable mirror, and to generate a plurality of sub-images from the input beam. The system further comprises a processor configured to measure, for each sub-image, two linear coefficients corresponding to a local wavefront aberration of the sub-image and to estimate, for each sub-image, three quadratic coefficients corresponding to the local wavefront aberration of the sub-image. The processor is further configured to reconstruct the aberrated wavefront of the input beam based on the measured linear coefficients and the estimated quadratic coefficients, and to provide control signals based upon the reconstructed wavefront to the deformable mirror to mitigate aberrations in the input beam.

Method And System Of Performing Multiple Observations Using A Space-Based Telescope Comprising Independently Targetable Sensor Units
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US Patent:

7759621, Jul 20, 2010
Filed:

Oct 29, 2007
Appl. No.:

11/927103
Inventors:

Gopal Vasudevan - San Jose CA, US
John S. Camp - San Francisco CA, US
Edward A. Lemaster - Cupertino CA, US
Michael A. Gonzales - San Jose CA, US
Assignee:

Lockheed Martin Corporation - Bethesda MD
International Classification:

G01C 21/02
G01C 21/24
G01J 1/20
US Classification:

2502036, 2502031, 2502061, 35613901
Abstract:

Multiple observations using a reconfigurable space-based telescope are performed by independently targeting one or more sensor units, within a field of view, relative to a main body of the space-based telescope. The sensor units are capable of simultaneously obtaining an image of one or more targets, respectively. At least one of the sensor units is independently retargetable relative to the main body of the space-based telescope to obtain an image of at least one other target. Further, the sensor units are independently maneuverable in formation relative to the main body of the space-based telescope to obtain various lines of sight without changing an optical axis of the main body of the space-based telescope.

Near Field Diversity Method For Estimation And Correction Of Aberrations
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US Patent:

7928351, Apr 19, 2011
Filed:

May 10, 2004
Appl. No.:

10/842987
Inventors:

Gopal Vasudevan - San Jose CA, US
Robert Duncan Reardon - Mountain View CA, US
Eric Hartel Smith - San Jose CA, US
Kenneth John Triebes - San Jose CA, US
Assignee:

Lockheed Martin Corporation - Bethesda MD
International Classification:

G01J 1/42
US Classification:

2502019, 356121, 356512, 356521, 359846, 359849
Abstract:

System and method for estimating and correcting an aberration of an optical system. The method includes capturing a first plurality of images on a first plurality of planes. The first plurality of images is formed by at least the optical system. Additionally, the method includes processing at least information associated with the first plurality of images, and determining a first auxiliary function based upon at least the information associated with the first plurality of images. The first auxiliary function represents a first aberration of the optical system. Moreover, the method includes adjusting the optical system based upon at least information associated with the first auxiliary function.

Euv Collector System With Enhanced Euv Radiation Collection
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US Patent:

8587768, Nov 19, 2013
Filed:

Mar 11, 2011
Appl. No.:

13/065008
Inventors:

Natale M. Ceglio - Pleasanton CA, US
Gopal Vasudevan - San Jose CA, US
Assignee:

Media Lario S.R.L. - Bosisio Parini (LC)
International Classification:

G02B 5/10
G03B 27/42
G03B 27/54
G03B 27/72
US Classification:

355 71, 355 53, 355 67, 359853
Abstract:

A collector system for extreme ultraviolet (EUV) radiation includes a collector mirror and a radiation-collection enhancement device (RCED) arranged adjacent an aperture member of an illuminator. The collector mirror directs EUV radiation from an EUV radiation source towards the aperture member. The RCED redirects a portion of the EUV radiation that would not otherwise pass through the aperture of the aperture member or that would not have an optimum angular distribution, to pass through the aperture and to have an improved angular distribution better suited to input specifications of an illuminator. This provides the illuminator with greater amount of useable EUV radiation than would otherwise be available from the collector mirror alone, thereby enhancing the performing of an EUV lithography system that uses such a collector system with a RCED.

Euv Collector System With Enhanced Euv Radiation Collection
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US Patent:

20140043595, Feb 13, 2014
Filed:

Oct 17, 2013
Appl. No.:

14/056654
Inventors:

- Bosisio Parini, IT
Gopal Vasudevan - San Jose CA, US
Assignee:

Media Lario, S.R.L. - Bosisio Parini
International Classification:

G03F 7/20
G02B 5/08
US Classification:

355 71, 359350
Abstract:

A collector system for extreme ultraviolet (EUV) radiation includes a collector mirror and a radiation-collection enhancement device (RCED) arranged adjacent an aperture member of an illuminator. The collector mirror directs EUV radiation from an EUV radiation source towards the aperture member. The RCED redirects a portion of the EUV radiation that would not otherwise pass through the aperture of the aperture member or that would not have an optimum angular distribution, to pass through the aperture and to have an improved angular distribution better suited to input specifications of an illuminator. This provides the illuminator with greater amount of useable EUV radiation than would otherwise be available from the collector mirror alone, thereby enhancing the performing of an EUV lithography system that uses such a collector system with a RCED.

Method And Apparatus For Estimating Piston Using A Grism
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US Patent:

6909512, Jun 21, 2005
Filed:

May 30, 2003
Appl. No.:

10/449808
Inventors:

Gopal Vasudevan - San Jose CA, US
Eric Hartel Smith - San Jose CA, US
Robert Duncan Reardon - Mountain View CA, US
Assignee:

Lockheed Martin Corporation - Bethesda MD
International Classification:

G01B009/02
US Classification:

356521
Abstract:

A method is provided for reducing the piston of neighboring first and second surfaces illuminated by polychromatic light transmitted from an unresolved-light source such that light transmitted or reflected from the first surface is out of phase with light respectively transmitted or reflected from the second surface, and the out-of-phase light is passed through a grism that generates a fringe pattern in the far-field. According to one exemplary embodiment, the method includes Fourier transforming the fringe pattern to generate a two-dimensional (2D) power spectrum; generating the absolute value of the 2D power spectrum to form an absolute value representation; displaying the 2D the absolute value representation on a computer display; and reducing the piston to affect rotation of the absolute value representation on the computer display and approximately align a central axis of the absolute value representation with an axis that indicates approximate alignment of the first and second surfaces.