Richard Erwin Knox

Address:

9943 Burntfork St, Houston, TX 77064

VIN:

3N1BC13E17L435493

Make:

NISSAN

Model:

VERSA

Year:

2007

US Patent:

6339454, Jan 15, 2002

Filed:

Nov 20, 2000

Appl. No.:

09/715057

Inventors:

Richard M. Knox - Houston TX

Assignee:

Duke University - Durham NC

International Classification:

H04N 574

US Classification:

348788, 348781, 353 77, 353 98

Abstract:

An âextra-foldedâ projection display system includes a selectively reflective material (e. g. , a linear reflecting polarizer) placed immediately behind the systems imaging screen. The display system includes an image projector that projects an image beam containing light of a predetermined linear polarization toward the imaging screen. The linear reflecting polarizer reflects the light in the image beam away from the screen. The reflected image beam then encounters a Â-wavelength achromatic retarder which converts the linear polarization to circular polarization. The image beam next hits a mirror that reflects the light back through the Â-wavelength achromatic retarder, which converts the circular polarization back to linear polarization, with the polarization director rotated from the original polarization director. The linear reflecting polarizer then allows the light to pass through to the image screen.

US Patent:

6379011, Apr 30, 2002

Filed:

Apr 10, 2001

Appl. No.:

09/829817

Inventors:

Richard M. Knox - Houston TX

Assignee:

Duke University - Durham NC

International Classification:

G03B 2100

US Classification:

353 31

Abstract:

A full color image projection system is provided using two non-color-specific image sources and color-specific filters. The system is capable of projecting an image using one primary color from one image source and the other two primary colors from another image source. The system uses slower speed image sources than would be required with one source alternating between three colors, and exhibits higher resolution than would be obtained from a color-specific image source.

US Patent:

6390626, May 21, 2002

Filed:

Oct 17, 1996

Appl. No.:

08/730818

Inventors:

Richard M. Knox - Houston TX

Assignee:

Duke University - Durham NC

International Classification:

G03B 2114

US Classification:

353 20, 353 31, 353 84, 349 9

Abstract:

A light projection engine uses a wide angle reflecting polarizer material (preferably 3M DBEF brand double brightness enhancement filter) as a polarizing beamsplitter to direct polarized light to beam splitter/combiner (such as an X-cube dichroic reflector). The beam splitter/combiner then splits the directed polarized light into separate reflective LCD panels acting as light valves. The LCD panels alter the polarity of the incident light from 0 degrees up to 90 degrees to control which light is passes from the wide angle reflecting polarizer back towards the light source and which light has the necessary polarization change to allow it to pass from the wide angle reflecting polarizer to the lens system. After reflecting off of the LCD panels, the light goes back through the X-cube dichroic reflector, where it is recombined. The recombined light which is of a first polarity is transmitted from the reflecting polarizer to the lens system, while the recombined light which is of a second polarity is transmitted to the light source.

US Patent:

6490017, Dec 3, 2002

Filed:

Jan 28, 1999

Appl. No.:

09/238713

Inventors:

Austin L. Huang - Arlington TX
Richard M. Knox - Houston TX

Assignee:

Duke University - Durham NC

International Classification:

G02F 11335

US Classification:

349 97, 359495, 353 31

Abstract:

An electro-optic shutter is provided that includes first and second liquid crystal devices located along an optical path and first and second color-selective layers located between the first and second liquid crystal devices. Each liquid crystal device is adapted to rotate the polarization of incident light to a substantially orthogonal polarization in response to being in a first state, and to not substantially change the polarization of incident light in response to being in a second state. The first color-selective layer is adapted to transmit first and second colors and a first polarization of a third color. The second color-selective layer is adapted to transmit the first and the third colors and a second polarization of the second color that is substantially orthogonal to the first polarization. An electro-optic shutter is also provided that includes a color-selective layer, a liquid crystal device to receive light from the color-selective layer and a polarizer to receive light from the liquid crystal layer. The color-selective layer is adapted to transmit a first color, a first polarization of a second color, and a substantially orthogonal polarization of a third color.

US Patent:

6525750, Feb 25, 2003

Filed:

Mar 8, 1996

Appl. No.:

08/615019

Inventors:

Richard M. Knox - Houston TX

Assignee:

Duke University - Durham NC

International Classification:

G06F 116

US Classification:

345901, 345905, 361681

Abstract:

A display system for a computer includes an image projector located in the computer and oriented to project a computer-generated image from the computer. Alternatively, the display system includes a screen and an image projector attached to the screen, where the screen is capable of receiving a computer-generated image projected by the image projector. Alternatively, the display system includes an image projector and a screen that is attached to the computer and that is capable of displaying an image projected by the image projector.

US Patent:

6535196, Mar 18, 2003

Filed:

May 3, 2001

Appl. No.:

09/846851

Inventors:

Dale S. Walker - Houston TX
Richard M. Knox - Houston TX

Assignee:

Duke University - Durham NC

International Classification:

G09G 336

US Classification:

345102, 345 88

Abstract:

In a color sequential system using LCDs, the LCD must operate faster than the frame rate because red, green, and blue are done sequentially. Ferroelectric LCDs can do this, but they are not analog devices and so cannot provide analog display levels. Instead, a pulse width modulation (PWM) technique is used. In the system of the present invention, each pixel has three storage devices to hold RGB analog levels. A latch is used to load these values in parallel. Then an analog 3:1 multiplexer is used to select the proper storage device for the current sequential color. The multiplexer output goes to a comparator, which has a sawtooth waveform input at much faster than the frame rate. The comparator output changes with the sawtooth level, so that PWM control is provided for each pixel. As an alternative, standard analog LCD pixels can be sequentially switched between three color input storage devices.

US Patent:

6547399, Apr 15, 2003

Filed:

Mar 18, 2002

Appl. No.:

10/100537

Inventors:

Richard M. Knox - Houston TX

Assignee:

Duke University - Durham NC

International Classification:

G03B 2100

US Classification:

353 31, 353 30, 353 34, 353 37, 353 81, 349 5, 349 9, 348743

Abstract:

A full color image projection system is provided using two non-color-specific image sources and color-specific filters. The system is capable of projecting an image using one primary color from one image source and the other two primary colors from another image source. The system uses slower speed image sources than would be required with one source alternating between three colors, and exhibits higher resolution than would be obtained from a color-specific image source.

US Patent:

6580471, Jun 17, 2003

Filed:

Jan 14, 2002

Appl. No.:

10/043228

Inventors:

Richard M. Knox - Houston TX

Assignee:

Duke University - Durham NC

International Classification:

H04N 574

US Classification:

348788, 348781, 353 77, 353 98

Abstract:

An âextra-foldedâ projection display system includes a selectively reflective material (e. g. , a linear reflecting polarizer) placed immediately behind the systems imaging screen. The display system includes an image projector that projects an image beam containing light of a predetermined linear polarization toward the imaging screen. The linear reflecting polarizer reflects the light in the image beam away from the screen. The reflected image beam then encounters a Â-wavelength achromatic retarder which converts the linear polarization to circular polarization. The image beam next hits a mirror that reflects the light back through the Â-wavelength achromatic retarder, which converts the circular polarization back to linear polarization, with the polarization director rotated 90Â from the original polarization director. The linear reflecting polarizer then allows the light to pass through to the image screen.