Benjamin D Lee

US Patent:

6831750, Dec 14, 2004

Filed:

May 31, 2002

Appl. No.:

10/160377

Inventors:

David J. Mehrl - Plano TX
Kun Pan - Allen TX
Benjamin L. Lee - Duncanville TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G01B 1114

US Classification:

356614, 356138

Abstract:

A method and system for indirectly measuring the tilt angle of micromirrors in a micromirror array. The method and system aims a coherent light beam through an aperture in a screen so that it reflects off of the surface of the micromirror array and creates a pattern of reflected light on the screen. The micromirror array is loaded with a pattern that has a uniform power spectral density (such as a random, aperiodic pattern or a frequency chirped sinusoidal spatial pattern) whereby certain micromirrors will be placed in the âonâ position and the other micromirrors will be placed in the âoffâ position. By loading the micromirror array with a pattern having a uniform power spectral density distribution, the discrete nature of the resulting diffraction pattern is reduced and a pair of [sin(x)/x] patterns will be generated on the screen. These [sin(x)/x] patterns can be used to measure a variety of characteristics of the micromirrors, such as tilt angle, ârollâ, and deformation of the mirrors as they are tilted.

US Patent:

6943950, Sep 13, 2005

Filed:

Aug 7, 2001

Appl. No.:

09/923911

Inventors:

Benjamin L. Lee - Dallas TX, US
Claude E. Tew - Dallas TX, US
Walter M. Duncan - Dallas TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G02B005/18

US Classification:

359571, 359290

Abstract:

A method for assuring a blazed condition in a DMD device used in telecommunications applications. By meeting certain conditions in the fabrication and operation of the DMD, the device can achieve a blazed condition and be very effective in switching near monochromatic spatially coherent light, thereby opening up a whole new application field for such devices. This method determines the optimal pixel pitch and mirror tilt angle for a given incident angle and wavelength of near monochromatic spatially coherent light to assure blazed operating conditions. The Fraunhofer envelope is determined by convolving the Fourier transforms of the mirror aperture and the delta function at the center of each mirror and then aligning the center of this envelope with a diffraction order to provide a blazed condition. The method of the present invention presents a formula for precisely determining the mirror pitch and tilt angle to assure that a blazed condition exists for a given incident angle and wavelength of near monochromatic spatially coherent light. Considerations for the special case, know as Littrow conditions, where the incident and the reflected light transverse the same path, are also given.

US Patent:

6958841, Oct 25, 2005

Filed:

May 23, 2002

Appl. No.:

10/154257

Inventors:

Paul L. Rancuret - Plano TX, US
Terry A. Barlett - Dallas TX, US
Benjamin L. Lee - Duncanville TX, US
Elisabeth Marley Koontz - Dallas TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G02B026/00
G02F001/01

US Classification:

359239, 359291, 359292

Abstract:

Disclosed is a method for generating patterns to be used in a spatial light modulator having a plurality of pixels. The method includes generating an optical pattern to be placed upon the pixels of the spatial light modulator, applying the optical pattern to the pixels of the spatial light modulator, measuring the optical performance of the plurality of pixels having the optical pattern applied to it, comparing the measured optical performance to a target optical performance, and adjusting the optical pattern applied to the plurality of pixels to form another optical pattern that more closely achieves the target optical performance.

US Patent:

7167143, Jan 23, 2007

Filed:

May 30, 2003

Appl. No.:

10/449793

Inventors:

Benjamin Lowell Lee - Duncanville TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G09G 3/00

US Classification:

345 30, 345 32

Abstract:

The present application describes a system and method for determining characteristics (e. g. , exact band location, orientation and height and the spot shape and size of a single wavelength and the like) of an optical signal projected on a spatial light modulator. In an embodiment, images with sharper edges (i. e. clear boundary between ‘on’ pixels and ‘off’ pixels) on the spatial light modulator are used to obtain spectral information from a referenced broadband source. The spectral information can be used to determine the desired characteristics of optical signals projected on the spatial light modulator.

US Patent:

7171068, Jan 30, 2007

Filed:

Dec 20, 2002

Appl. No.:

10/326231

Inventors:

Terry Bartlett - Dallas TX, US
Benjamin L. Lee - Duncanville TX, US
Bryce D. Sawyers - Allen TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G02B 6/26
G02B 26/00

US Classification:

385 17, 385 18, 385 28, 385 37, 385 39, 385 40, 385 41, 385 47, 359291, 359298, 3593375, 359338

Abstract:

A method to improve an extinction ratio of an optical device, the method includes positioning at least a majority of a plurality of micro-mirrors in an off-state position. A mirror assembly includes the plurality of micro-mirrors. The method also includes selectively positioning at least one of the plurality of micro-mirrors in an on-state position. In one particular embodiment, the at least one of the plurality of micro-mirrors positioned in the on-state position operates to improve an extinction ratio of an optical device.

US Patent:

7630135, Dec 8, 2009

Filed:

Sep 12, 2005

Appl. No.:

11/224336

Inventors:

Benjamin L. Lee - Dallas TX, US
Claude E. Tew - Dallas TX, US
Walter M. Duncan - Dallas TX, US

Assignee:

Texas Instrument Incorporated - Dallas TX

International Classification:

G02B 5/18
H04J 14/02

US Classification:

359573, 359571, 398 84, 398 87

Abstract:

A method for assuring a blazed condition in a DMD device used in telecommunications applications. By meeting certain conditions in the fabrication and operation of the DMD, the device can achieve a blazed condition and be very effective in switching near monochromatic spatially coherent light, thereby opening up a whole new application field for such devices. This method determines the optimal pixel pitch and mirror tilt angle for a given incident angle and wavelength of near monochromatic spatially coherent light to assure blazed operating conditions. The Fraunhofer envelope is determined by convolving the Fourier transforms of the mirror aperture and the delta function at the center of each mirror and then aligning the center of this envelope with a diffraction order to provide a blazed condition. The method of the present invention presents a formula for precisely determining the mirror pitch and tilt angle to assure that a blazed condition exists for a given incident angle and wavelength of near monochromatic spatially coherent light. Considerations for the special case, know as Littrow conditions, where the incident and the reflected light transverse the same path, are also given.

US Patent:

7652657, Jan 26, 2010

Filed:

Dec 13, 2006

Appl. No.:

11/610394

Inventors:

Benjamin Lowell Lee - Duncanville TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G09G 3/34

US Classification:

345108, 345 30, 345 32, 345107

Abstract:

The present application describes a system and method for determining characteristics (e. g. , exact band location, orientation and height and the spot shape and size of a single wavelength and the like) of an optical signal projected on a spatial light modulator. In an embodiment, images with sharper edges (i. e. clear boundary between ‘on’ pixels and ‘off’ pixels) on the spatial light modulator are used to obtain spectral information from a referenced broadband source. The spectral information can be used to determine the desired characteristics of optical signals projected on the spatial light modulator.

US Patent:

8235532, Aug 7, 2012

Filed:

Apr 30, 2009

Appl. No.:

12/432862

Inventors:

Walter Marvin Duncan - Dallas TX, US
Benjamin Lowell Lee - Duncanville TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G03B 21/26

US Classification:

353 34, 353 30

Abstract:

A system comprises two or more light sources comprising a first light source and a second light source, each light source of the two or more light sources configured to provide light of a particular wavelength, wherein a first wavelength of a first light provided by the first light source differs from a second wavelength of a second light provided by the second light source, and wherein the first light has a first radiant energy that experiences roll-off. The system further comprises a controller configured to modulate an attribute of each light source to compensate for the roll-off, the modulation comprising modulating an attribute of the first light source, and the modulation further comprising modulating an attribute of the second light source, the modulation of the second attribute being different from the modulation of the first attribute.