Michael W O'Callaghan

US Patent:

7656768, Feb 2, 2010

Filed:

Jan 27, 2005

Appl. No.:

11/046197

Inventors:

Mark A. Handschy - Boulder CO, US
Michael J. O'Callaghan - Louisville CO, US
Christopher M. Walker - Boulder CO, US

Assignee:

Micron Technology, Inc. - Boise ID

International Classification:

G11B 7/00

US Classification:

36911202, 369103

Abstract:

A spatial light modulator (SLM) having a phase mask that is provided as an internal component thereof. The phase mask can be provided as a multilevel surface of relatively higher index of refraction material on an inner surface of a transmissive cover window or as a separate transmissive window between the cover window and the pixels of the SLM. If the phase mask is to be used with a liquid crystal SLM, then it may be desirable to planarize the surface of the cover window contacting the liquid crystal by providing a layer of relatively lower index of refraction material adjacent the multilevel surface. The phase mask can also be provided on the transmissive cover window by patterned ion deposition, exposing patterned light to a photopolymeric material, or in some other suitable fashion. Arranging for the pixel electrodes to be at one of multiple levels rather than lying in an exactly planar relationship can also effectively create the phase mask.

US Patent:

7733557, Jun 8, 2010

Filed:

Apr 24, 2007

Appl. No.:

11/739642

Inventors:

Mark A. Handschy - Boulder CO, US
Michael J. O'Callaghan - Louisville CO, US

Assignee:

Micron Technology, Inc. - Boise ID

International Classification:

G02F 1/01
G02B 5/32
G03H 1/16
G11B 7/00

US Classification:

359279, 359245, 359320, 359237, 359561, 359 11, 359 15, 359 29, 359 35, 369103, 349 74, 349171, 345690

Abstract:

A holographic data storage system that includes a write head that includes a pixellated spatial light modulator and a separate or integral phase mask that varies the phase depending on the location in the phase mask that light passes through. The phase variation can be changed over time in a random, pseudo-random, or predetermined fashion. The spatial light modulator and phase mask can be implemented in a liquid crystal SLM (nematic, ferroelectric, or other), in a DMD SLM, in a magneto-optical SLM, or in any other suitable manner.

US Patent:

8107344, Jan 31, 2012

Filed:

Dec 16, 2009

Appl. No.:

12/639821

Inventors:

Mark A. Handschy - Boulder CO, US
Michael J. O'Callaghan - Louisville CO, US
Christopher M. Walker - Boudler CO, US

Assignee:

Micron Technology, Inc. - Boise ID

International Classification:

G11B 7/00

US Classification:

36911202, 36911201, 369103

Abstract:

A spatial light modulator (SLM) having a phase mask that is provided as an internal component thereof. The phase mask can be provided as a multilevel surface of relatively higher index of refraction material on an inner surface of a transmissive cover window or as a separate transmissive window between the cover window and the pixels of the SLM. If the phase mask is to be used with a liquid crystal SLM, then it may be desirable to planarize the surface of the cover window contacting the liquid crystal by providing a layer of relatively lower index of refraction material adjacent the multilevel surface. The phase mask can also be provided on the transmissive cover window by patterned ion deposition, exposing patterned light to a photopolymeric material, or in some other suitable fashion. Arranging for the pixel electrodes to be at one of multiple levels rather than lying in an exactly planar relationship can also effectively create the phase mask.

US Patent:

8134771, Mar 13, 2012

Filed:

Apr 29, 2010

Appl. No.:

12/770444

Inventors:

Mark A. Handschy - Boulder CO, US
Michael J. O'Callaghan - Louisville CO, US

Assignee:

Micron Technology, Inc. - Boise ID

International Classification:

G02F 1/01
G02B 26/00
G03H 1/12

US Classification:

359279, 359290, 359 11, 359 22, 359 32, 359 35, 369103, 36911202, 356450, 356512

Abstract:

A holographic data storage system that includes a write head that includes a pixellated spatial light modulator and a separate or integral phase mask that varies the phase depending on the location in the phase mask that light passes through. The phase variation can be changed over time in a random, pseudo-random, or predetermined fashion. The spatial light modulator and phase mask can be implemented in a liquid crystal SLM (nematic, ferroeleletric, or other), in a DMD SLM, in a magneto-optical SLM, or in any other suitable manner.

US Patent:

20130194556, Aug 1, 2013

Filed:

Jan 31, 2013

Appl. No.:

13/756225

Inventors:

Citizen Finetech Miyota Co., LTD - Miyota, JP
Michael J. O'Callaghan - Louisville CO, US

Assignee:

Citizen Finetech Miyota Co., LTD - Miyota

International Classification:

G02B 27/28
G03B 21/14

US Classification:

353121, 362 19

Abstract:

An illumination system for a pico-projector that provides polarization conversion includes the combination of an optical element with a series of stacked, elongated PBSs, where alternate ones of the PBSs have a half-wave plate film applied to a back side thereof and a retarder stack film (RSF) that flips or passes different linear polarization orientations based on the wavelength of light. This combination is placed at a position in the illumination system where the impinging light is collimated to at least some degree.

US Patent:

20140009731, Jan 9, 2014

Filed:

Jul 9, 2012

Appl. No.:

13/544476

Inventors:

Michael O'Callaghan - Louisville CO, US
Wanli Chi - Longmont CO, US
Mark Handschy - Boulder CO, US

International Classification:

G02F 1/1335
G02F 1/1343

US Classification:

349114, 349113

Abstract:

A liquid crystal panel and method are disclosed for increasing optical efficiency in the panel by using a reflector with a high fill factor and arranging an array of transparent pixel electrodes between the reflector and a layer of liquid crystal.

US Patent:

51826658, Jan 26, 1993

Filed:

Sep 7, 1990

Appl. No.:

7/578647

Inventors:

Michael J. O'Callaghan - Louisville CO
Mark A. Handschy - Boulder CO

Assignee:

Displaytech, Inc. - Boulder CO

International Classification:

G02F 113

US Classification:

359 95

Abstract:

An arrangement (apparatus and method) for selectively modulating incident unpolarized light passing through a birefringent material, such as ferroelectric crystal. The apparatus includes a plate having one or more birefringent layers. The birefringent layer has an optic axis selectably set in a first orientation and a second orientation. A switching means controls the optical axis state of voltages to the areas of the birefringent layer. Light having passed through the birefringent layer at locations having the first orientation have a different phase from, and same polarization as, light having passed through locations with the second orientation, independent of a polarization state of the incident light. As a result, the birefringent material has a uniform state at locations where the correspon BACKGROUND OF THE INVENTION Government Contract Clause This invention was made with Government support un contract F29601-89-C-0075 awarded by the Department of the Air Force. The Government may have certain rights in this invention.

US Patent:

55529160, Sep 3, 1996

Filed:

Jan 25, 1993

Appl. No.:

8/008764

Inventors:

Michael J. O'Callaghan - Louisville CO
Mark A. Handschy - Boulder CO

Assignee:

Displaytech, Inc. - Boulder CO

International Classification:

G02F 113

US Classification:

359 95

Abstract:

An arrangement (apparatus and method) for selectively modulating incident unpolarized light passing through a birefringent material, such as ferroelectric crystal. The apparatus includes a plate having one or more birefringent layers corresponding to first and second alignment regions. The birefringent layer corresponding to the first alignment region has a first optic axis selectably set in a first orientation and a second orientation. The birefringent layer corresponding to the second alignment region has a second optic axis selectably set in a third orientation and a fourth orientation. A switching means controls the optical axis states of the birefringent material by applying switching voltages to the areas of the birefringent layer. Light having passed through the birefringent layer at locations having the first orientation has a different phase from, and same polarization as, light having passed through locations with the third orientation, independent of a polarization state of the incident light. As a result, the birefringent material has a uniform state at locations where the corresponding optic axes between the first and second alignment regions are parallel, and a diffracting state produced by an interaction between the light having passed through areas having the first orientation and the light having passed through areas having the second orientation.