Richard R Griffiths

US Patent:

48126454, Mar 14, 1989

Filed:

Mar 27, 1987

Appl. No.:

7/032042

Inventors:

Richard W. Griffiths - Pacific Palisades CA

Assignee:

G2 Systems Corporation - Pacific Palisades CA

International Classification:

G01L 124

US Classification:

250227

Abstract:

An optical fiber is securely and continuously engaged by a structure such as a pipeline, offshore platform, bridge, building, dam or even a natural object or fluid medium. A light signal is passed into one end of the optical fiber. Any physical movement of the structure, or sectional movements along the optical fiber path, such as deflection, bending, displacement (changes in linear uniformity) or fracture of the structure caused, for example, by stress, strain, pressure, temperature, etc. , will necessarily affect the optical fiber. As a consequence, detectable changes will occur in the "electro-optic signature" (for measurements made at the input end of the optical fiber) or in the light signal transmission (for measurements made at the opposite end of the optical fiber). Such measurements made at the input end include reflections resulting from Rayleigh back-scattering and can periodically or continuously be made to determine the magnitude and location of the aforementioned physical movements of the structure. In addition, by utilizing additional optical fibers, the direction and rate, i. e.

US Patent:

46545204, Mar 31, 1987

Filed:

Mar 18, 1985

Appl. No.:

6/712889

Inventors:

Richard W. Griffiths - Pacific Palisades CA

International Classification:

G01L 124

US Classification:

250227

Abstract:

An optical fiber is securely and continuously fastened to a structure such as a pipeline, offshore platform, bridge, building, dam or even a natural object. A light signal is passed into one end of the optical fiber. Any physical movement of the structure, or sectional movements along the optical fiber path, such as deflection, bending, displacement (changes in linear uniformity) or fracture of the structure will necessarily affect the optical fiber. As a consequence, detectable changes will occur in the "electro-optic signature" (for measurements made at the input end of the optical fiber) or in the light signal transmission (for measurements made at the opposite end of the optical fiber). Such measurements made at the input include reflections resulting from Rayleigh back-scattering and can be periodically or continuously made to determine the magnitude and location of the aforementioned physical movements of the structure. In addition, by utilizing additional optical fibers, the direction and rate, i. e.

US Patent:

50261410, Jun 25, 1991

Filed:

Oct 30, 1989

Appl. No.:

7/428881

Inventors:

Richard W. Griffiths - Pacific Palisades CA

Assignee:

G2 Systems Corporation - Pacific Palisades CA

International Classification:

G02B 626

US Classification:

350 9629

Abstract:

An optical fiber is securely and continuously engaged by a structure such as a pipeline, offshore platform, bridge, building, dam or even a natural object or fluid medium. A light signal is passed into one end of the optical fiber. Any physical movement of the structure, or sectional movements along the optical fiber path, such as deflection, bending, displacement (changes in linear uniformity) or fracture of the structure caused, for example, by stress, strain, pressure, temperature, etc. , will necessarily affect the optical fiber. As a consequence, detectable changes will occur in the "electro-optic signature" (for measurements made at the input end of the optical fiber) or in the light signal transmission (for measurements made at the opposite end of the optical fiber). A preferred optic fiber construction comprises a core and cladding contained within a protective buffer coating, wherein the buffer coating includes a particulate material for engaging the cladding in a manner altering reflective or transmission or other "electro-optic signature" characteristics of the fiber when the buffer coating is subjected to radial forces. The particulate material can be uniformly or nonuniformly distributed about the cladding to provide variable sensitivity.

US Patent:

49272322, May 22, 1990

Filed:

Mar 13, 1989

Appl. No.:

7/323498

Inventors:

Richard W. Griffiths - Pacific Palisades CA

Assignee:

G2 Systems Corporation - Pacific Palisades CA

International Classification:

G02B 616

US Classification:

350 9629

Abstract:

An optical fiber is securely and continuously engaged by a structure such as a pipeline, offshore platform, bridge, building, dam or even a natural object or fluid medium. A light signal is passed into one end of the optical fiber. Any physical movement of the structure, or sectional movements along the optical fiber path, such as deflection, bending, displacement (changes in linear uniformity) or fracture of the structure caused, for example, by strees, strain, pressure, temperature, etc. , will necessarily affect the optical fiber. As a consequence, detectable changes will occur in the "electro-optic signature" (for measurements made at the input end of the optical fiber) or in the light signal transmission (for measurements made at the opposite end of the optical fiber). A preferred optic fiber construction comprises a core and cladding contained within a protective buffer coating, wherein the buffer coating includes a particulate material for engaging the cladding in a manner altering reflective or transmission or other "electro-optic signature" characteristics of the fiber when the buffer coating is subjected to radial forces. The particulate material can be uniformly or nonuniformly distributed about the cladding to provide variable sensitivity.