Robert R Christensen

US Patent:

7193765, Mar 20, 2007

Filed:

Mar 31, 2005

Appl. No.:

11/097462

Inventors:

Robert R. Christensen - Salt Lake City UT, US
Forrest L. Williams - Sandy UT, US
Allen H. Tanner - Sandy UT, US

Assignee:

Evans & Sutherland Computer Corporation - Salt Lake City UT

International Classification:

G02F 1/01

US Classification:

359279

Abstract:

The invention provides a system and method for reducing laser speckle and interference patterns in a laser projector display when using a laser projector having a spatial light modulator (SLM) with a defined pixel rate. The method can include the operation of polarizing a laser output of a continuous wave laser such that the laser output is s-polarized with respect to a beam combiner. The s-polarized laser output can be divided into a first laser beam and a second laser beam. A phase of the second laser beam can be modulated with an amplitude sufficient to create a phase delay of approximately half a wavelength of the laser output and at a frequency at least twice that of the SLM's pixel rate.

US Patent:

7334902, Feb 26, 2008

Filed:

Mar 28, 2005

Appl. No.:

11/092128

Inventors:

Harry Streid - Salt Lake City UT, US
Robert R. Christensen - Salt Lake City UT, US
Allen H. Tanner - Sandy UT, US

Assignee:

Evans & Sutherland Computer Corporation - Salt Lake City UT

International Classification:

G03B 21/28
G03B 21/56

US Classification:

353 98, 359451

Abstract:

A wide angle display system includes a linear array projector, a curved display surface, and an n-sides scanning mirror. The projector is configured to project an image along an optical axis to the scanning mirror. The scanning mirror continuously rotates about a rotational axis at a speed 1/n the refresh rate, so as to reflect and scan the image onto the display surface.

US Patent:

7400449, Jul 15, 2008

Filed:

Sep 29, 2006

Appl. No.:

11/541154

Inventors:

Robert R. Christensen - Salt Lake City UT, US
Forrest L. Williams - Sandy UT, US
Allen H. Tanner - Sandy UT, US

Assignee:

Evans & Sutherland Computer Corporation - Salt Lake City UT

International Classification:

G02B 5/18
G02B 27/44

US Classification:

359566, 359558

Abstract:

A system and method is disclosed for reducing visibility of image artifacts caused by diffractive elements in a laser projector having a structured diffractive device. At least two diffracted orders of light can be selected from light emitted from the structured diffractive device using a spatial light filter. The polarization of at least one of the selected diffracted orders can be changed with respect to another selected diffracted order. The selected diffracted order can be recombined to form an image having reduced visible image artifacts.

US Patent:

7420177, Sep 2, 2008

Filed:

Jan 20, 2006

Appl. No.:

11/336510

Inventors:

Forrest Williams - Sandy UT, US
Robert R. Christensen - Salt Lake City UT, US
Allen H. Tanner - Sandy UT, US

Assignee:

Evans & Sutherland Computer Corporation - Salt Lake City UT

International Classification:

G03B 21/00

US Classification:

25037008, 353 31, 353 98, 348756, 348 36, 359245, 359634

Abstract:

A system and method for generating a high-resolution image using a scanned-column projector is disclosed. The method includes the operation of generating a time-varying line image. A further operation includes collimating the time-varying line image in at least one plane. An additional operation involves scanning the collimated time-varying line image using a scan mirror. A further operation includes projecting the scanned collimated time-varying line image onto a surface. The scanned collimated time-varying line image is projected with at least one imaging element.

US Patent:

7891818, Feb 22, 2011

Filed:

Dec 12, 2007

Appl. No.:

12/001771

Inventors:

Robert R. Christensen - Rapid City SD, US
Bret D. Winkler - South Jordan UT, US
Dennis Elkins - Draper UT, US
Allen H. Tanner - Sandy UT, US

Assignee:

Evans & Sutherland Computer Corporation - Salt Lake City UT

International Classification:

G03B 21/00

US Classification:

353 31, 353 84, 353 94, 353 76, 353122, 372 25, 372 28, 372 2902, 372 6, 372 30, 348754, 348769, 348 E5139, 348311, 348750, 348203, 348756, 348205, 359291, 359238, 359276, 359278, 359290

Abstract:

A projection system that includes a singe light modulation device and a plurality of light sources of different wavelengths. Each wavelength of light is incident on the light modulation device at a spatially distinct location and a temporally distinct time. The use of a scanning mirror allows the projection system to sequentially form, in full-color, each of the columns or rows of an image. The projection system is characterized by the reduction of color separation or the rainbow effect due to the rendering of each column or row in full color.

US Patent:

20090002644, Jan 1, 2009

Filed:

May 21, 2008

Appl. No.:

12/124956

Inventors:

Robert R. Christensen - Rapid City SD, US
Bret D. Winkler - South Jordan UT, US
Allen H. Tanner - Sandy UT, US
Jeffery J. Waite - Salt Lake City UT, US
Dennis F. Elkins - Draper UT, US
Michael J. McMahon - Sandy UT, US
Forrest L. Williams - Sandy UT, US

Assignee:

EVANS & SUTHERLAND COMPUTER CORPORATION - Salt Lake City UT

International Classification:

F16P 3/14
G03B 21/14

US Classification:

353 85, 2505594

Abstract:

An invisible scanning safety system for use with laser projection systems that includes sensors monitoring less than the entire laser accessible region such that the region monitored is reduced to almost the absolute minimum, to thereby prevent unwarranted stoppages or disturbances in projection. The system may also monitor a 360 degree region around the lens of the laser projector, a wedge-shaped region, a pyramid-shaped region or a chimney-shaped region.

US Patent:

20090168186, Jul 2, 2009

Filed:

Sep 8, 2008

Appl. No.:

12/206582

Inventors:

Forrest Williams - Sandy UT, US
Robert Christensen - Rapid City SD, US
Allen Tanner - Sandy UT, US

International Classification:

G02B 27/10

US Classification:

359621, 359627

Abstract:

An optical assembly for reducing the etendue of a diode laser light source having a plurality of laser light emitters. The optical assembly comprises a first optical device for collimating beams of light emitted from the emitters of the diode laser. A second optical device spatially shifts a portion of the collimated light beams emitted from the diode laser to thereby reduce gaps or dark space between the beams. A third optical device focuses all of the light beams onto a surface, such as a surface of a light modulation surface.

US Patent:

20090219491, Sep 3, 2009

Filed:

Oct 20, 2008

Appl. No.:

12/288577

Inventors:

Forrest Williams - Sandy UT, US
Robert Christensen - Rapid City SD, US
David M. Bloom - Jackson WY, US
Allen Tanner - Sandy UT, US

Assignee:

Evans & Sutherland Computer Corporation - Salt Lake City UT

International Classification:

G03B 21/28
G02B 26/00
H01S 3/00

US Classification:

353 37, 359290, 362553

Abstract:

An illumination system for transforming at least one laser light beam having a non-uniform distribution in a first axis and a second axis to a beam having a substantially uniform distribution in the first axis while preserving the non-uniform distribution in the second axis. The transformed beam may be imaged as a line image onto a one-dimensional light modulation device. The illumination system may comprise a light tunnel having two sides that interact with the at least one laser light beam in the first axis and two sides that do not interact with the light in the second axis.