Stephen Walter Perkins

US Patent:

6515784, Feb 4, 2003

Filed:

Apr 24, 2001

Appl. No.:

09/840858

Inventors:

Bruce A. Ferguson - Redondo Beach CA
Richard A. Fields - Redondo Beach CA
Mark Kintis - Manhattan Beach CA
Elizabeth T. Kunkee - Manhattan Beach CA
Lawrence J. Lembo - Torrance CA
Stephen R. Perkins - Harbor City CA
David L. Rollins - Woodinville WA
Eric L. Upton - Bellevue WA

Assignee:

TRW Inc. - Redondo Beach CA

International Classification:

G02F 103

US Classification:

359244, 3593491, 250214 DC

Abstract:

An optical inverting system employs a first optical structure having an index of refraction that varies with the intensity of an incident beam and a second optical structure having a constant index of refraction, and forming an interface therebetween. An optical pulse stream is combined with a laser beam and the combined beam is applied to the first optical structure, impinging the interface at a predetermined angle of incidence. If the angle of incidence is less than a critical angle, the beam is refracted into the second optical structure. If the angle of incidence is greater than the critical angle, the beam is completely reflected at the interface. Thus the output of the second optical structure is an inversion, and the output of the first optical structure is a level shifted replica, of the optical digital pulse stream.

US Patent:

6529674, Mar 4, 2003

Filed:

Nov 29, 2001

Appl. No.:

09/998545

Inventors:

Richard A. Fields - Redondo Beach CA
Bruce A. Ferguson - Redondo Beach CA
Mark Kintis - Manhattan Beach CA
Elizabeth T. Kunkee - Manhattan Beach CA
Lawrence J. Lembo - Torrance CA
Stephen R. Perkins - Harbor City CA
David L. Rollins - Hawthorne CA
Eric L. Upton - Redondo Beach CA

Assignee:

TRW Inc. - Redondo Beach CA

International Classification:

G02B 600

US Classification:

385140

Abstract:

An optical device for use with an optical input beam comprising an optical thresholding device positioned along an optical path defined by the propagation direction of the optical input beam. If the combined intensity of the optical input beam and a control beam exceeds a threshold level, the optical beam passes through the thresholding device. Preferably, the optical thresholding device is a saturable absorber. When the device is configured as an optical comparator, the intensity of the optical input beam exceeds the threshold level and the thresholding device saturates and turns transparent so that the control beam passes through the thresholding device as an optical indicator beam. When the device is configured as an optical signal attenuator and the intensity of the optical input signal is negligible compared to that of the control beam, the combined intensity of the beams does not saturate the thresholding device.

US Patent:

20020037148, Mar 28, 2002

Filed:

Nov 30, 2001

Appl. No.:

09/999556

Inventors:

Richard Fields - Redondo Beach CA, US
Bruce Ferguson - Redondo Beach CA, US
Mark Kintis - Manhattan Beach CA, US
Elizabeth Kunkee - Manhattan Beach CA, US
Lawrence Lembo - Torrance CA, US
Stephen Perkins - Harbor City CA, US
David Rollins - Hawthorne CA, US
Eric Upton - Redondo Beach CA, US

Assignee:

TRW Inc.

International Classification:

G02B006/26

US Classification:

385/140000

Abstract:

An optical device for use with an optical input beam comprises and optical thresholding device having a predetermined threshold level, and is positioned along an optical path defined by the propagation direction of the optical input beam. A source generates a control beam through the optical thresholding device, wherein if the combined intensity of the optical input beam and the control beam is large enough to exceed the threshold level of the thresholding device, the optical beam passes through he thresholding device. The thresholding device attenuates the optical beam as it passes therethrough. In a preferred embodiment, the optical thresholding device is a saturable absorber. When the device is configured as an optical comparator, the intensity of the optical input beam is large enough to exceed the threshold level of the thresholding device, the thresholding device saturates and turns transparent so that the control beam passes through the thresholding device as an optical indicator beam and the optical input beam passes through the thresholding device. When configured as an optical signal attenuator and the intensity of the optical input signal is negligible compared to that of the control beam the combined intensity of the optical input signal and the control beam do not saturate the thresholding device.

US Patent:

63273993, Dec 4, 2001

Filed:

Nov 22, 1999

Appl. No.:

9/444977

Inventors:

Richard A. Fields - Redondo Beach CA
Bruce A. Ferguson - Redondo Beach CA
Mark Kintis - Manhattan Beach CA
Elizabeth T. Kunkee - Manhattan Beach CA
Lawrence J. Lembo - Torrance CA
Stephen R. Perkins - Harbor City CA
David L. Rollins - Hawthorne CA
Eric L. Upton - Redondo Beach CA

Assignee:

TRW Inc. - Redondo Beach CA

International Classification:

G02B 626

US Classification:

385 19

Abstract:

An optical device for use with an optical input beam comprises and optical thresholding device having a predetermined threshold level, and is positioned along an optical path defined by the propagation direction of the optical input beam. A source generates a control beam through the optical thresholding device, wherein if the combined intensity of the optical input beam and the control beam is large enough to exceed the threshold level of the thresholding device, the optical beam passes through he thresholding device. The thresholding device attenuates the optical beam as it passes therethrough. In a preferred embodiment, the optical thresholding device is a saturable absorber. When the device is configured as an optical comparator, the intensity of the optical input beam is large enough to exceed the threshold level of the thresholding device, the thresholding device saturates and turns transparent so that the control beam passes through the thresholding device as an optical indicator beam and the optical input beam passes through the thresholding device. When configured as an optical signal attenuator and the intensity of the optical input signal is negligible compared to that of the control beam the combined intensity of the optical input signal and the control beam do not saturate the thresholding device.

US Patent:

6121907, Sep 19, 2000

Filed:

Aug 11, 1998

Appl. No.:

9/133038

Inventors:

Richard A. Fields - Redondo Beach CA
David L. Rollins - Hawthorne CA
Stephen R. Perkins - Redondo Beach CA
Eric L. Upton - Redondo Beach CA
Elizabeth T. Kunkee - Manhattan Beach CA
Lawrence J. Lembo - Torrance CA
Juan C. Carillo - Torrance CA
Mark Kintis - Manhattan Beach CA

Assignee:

TRW Inc. - Redondo Beach CA

International Classification:

H03M 100

US Classification:

341137

Abstract:

An optical analog-to-digital converter (10) which fully operates in the optical domain and utilizes an upward-folding successive approximation approach for conversion. The converter (10) includes a plurality of optical stages (14, 16, 18) where each stage (14, 16, 18) generates a digital bit. Each stage (14, 16, 18) includes an optical threshold switch (30, 56, 78) that sets the bit high when the switch (30, 56, 78) is closed. When a sample amplitude of the analog signal is compared to a threshold value and found to exceed the threshold value, the bit is set to "high" and the sample is passed directly onto the next stage (14, 16, 18). If the sample amplitude is found to be less than the threshold value, the bit is set to "low" and an intensity equal to the maximum signal intensity minus the threshold intensity is added to the sample amplitude. Each successive stage (14, 16, 18) compares the normalized signal sample to thresholds growing closer and closer to the maximum signal intensity. Multiple bits can be obtained by cascading stages.

US Patent:

62921193, Sep 18, 2001

Filed:

Jun 30, 1999

Appl. No.:

9/345295

Inventors:

Juan C. Carillo - Torrance CA
Bruce A. Ferguson - Redondo Beach CA
Richard A. Fields - Redondo Beach CA
Mark Kintis - Manhattan Beach CA
Elizabeth T. Kunkee - Manhattan Beach CA
Lawrence J. Lembo - Torrance CA
Stephen R. Perkins - Redondo Beach CA
David L. Rollins - Hawthorne CA
Eric L. Upton - Redondo Beach CA

Assignee:

TRW Inc. - Redondo Beach CA

International Classification:

H03M 100

US Classification:

341137

Abstract:

An optical analog-to-digital converter (10) that makes use of a downward-folding successive approximation conversion scheme that employs subtraction of optical signals. A pulsed optical signal (20) to be converted is applied as an input to each of a plurality of converter channels (12, 14, 16, 18), where each channel (12, 14, 16, 18) outputs one of the bits of the digital output of the converter (10). The input signal (20) to each channel (12, 14, 16, 18) is sent to a thresholding device (24, 40, 60, 80) that determines whether the intensity of the signal is greater than or less than a predetermined threshold value. The first channel thresholding device (24) compares the input signal (20) to a threshold value that is one-half of a known maximum intensity. Subsequent channel thresholding devices (40, 60, 80) compare the input signal to a threshold value that is one-half of the intensity used in the previous channel in a downward-folding scheme. If the intensity of the input signal (20) is greater than the threshold value in a particular channel (12, 14, 16, 18), then that threshold value is subtracted from the input signal (20) in each of the successive channels before being applied to the thresholding device (40, 60, 80) in that channel (14, 16, 18).

US Patent:

60350792, Mar 7, 2000

Filed:

Aug 11, 1998

Appl. No.:

9/133032

Inventors:

Richard A. Fields - Redondo Beach CA
David L. Rollins - Hawthorne CA
Stephen R. Perkins - Redondo Beach CA
Eric L. Upton - Redondo Beach CA
Elizabeth T. Kunkee - Manhattan Beach CA
Lawrence J. Lembo - Torrance CA
Juan C. Carillo - Torrance CA
Mark Kintis - Manhattan Beach CA

Assignee:

TRW Inc. - Redondo Beach CA

International Classification:

G02B 626

US Classification:

385 19

Abstract:

An optical inverter (10) that uses a saturable absorber (28) to distinguish between a logical one and a logical zero. A low power laser (18) generates an optical beam that is split into a first beam that propagates among a first beam path (24) and a second beam that propagates along a second beam path (26). The saturable absorber (28) is an optical switch that is positioned in the first beam path (24), and is switched from an opaque mode to a transparent mode when it receives an optical input signal. The first beam and the second beam are recombined as an optical output beam in an optical combiner (30). The first beam path (24) and the second beam path (26) have a length relative to each other such that the first and second beams are 180. degree. out of phase when they reach the optical combiner (30). Therefore, if the saturable absorber (28) is switched to the transparent mode, the first and second beams combine destructively and the optical output beam is dark, or a logical zero.

US Patent:

61609307, Dec 12, 2000

Filed:

Aug 11, 1998

Appl. No.:

9/133036

Inventors:

Bruce A. Ferguson - Redondo Beach CA
Richard A. Fields - Redondo Beach CA
Mark Kintis - Manhatten Beach CA
Elizabeth T. Kunkee - Manhatten Beach CA
Lawrence J. Lembo - Torrance CA
Stephen R. Perkins - Redondo Beach CA
David L. Rollins - Hawthorne CA
Eric L. Upton - Redondo Beach CA

Assignee:

TRW Inc. - Redondo Beach CA

International Classification:

G02B 626

US Classification:

385 24

Abstract:

The optical hold unit (100) of the present invention includes an optical modulator (108) that has an electrical input, an optical input, and an optical output. A 1. times. N optical splitter (106) is also provided that has an optical input and N optical outputs. In addition, N optical paths (112) are individually coupled to the N optical outputs and carry one of the N output signals. Each optical path has an associated propagation delay. Optical delay elements may be located in any of the N optical paths that carry the output signals. The optical delay elements serve to lengthen the propagation delay (114a-e) of the optical path (112a-e) in which the optical delay element is located. In an alternative embodiment, the optical hold unit (200) includes an optical modulator (108) that has an electrical input, an optical input, and an optical output. An optical resonator (202) is also provided and connected to the optical output of the modulator (108).