Patent US4420251A successfully refreshed from Google Patents.
US4420251A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical deformation sensor
Assignee: Boeing North American Inc
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Filing: 1981-12-28
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Granted: 1983-12-13
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Expires: 2001-12-28
Abstract
Abstract This invention relates to a lightweight and compact optical sensor that provides an indication of a deformation (e.g. fatigue, vibration, flex, torsion, bending, slippage) occurring at a monitored area. The sensor includes at least one light transmitting optical fiber and an optical detector that is responsive to the optical characteristics (e.g. amplitude, phase, polarization angle) of a supply of light signals being transmitted through the fiber. In the event that deformation occurs at the monitored region, the optical fiber undergoes a displacement which thereby causes a corresponding change in the optical characteristics of the light signals supplied to the detector. The optical characteristics of the light signals supplied to the detector relative to those of the light signals supplied to the optical fiber provide an accurate indication of the physical parameter.
Inventors
- 👤 Kenneth A. James
- 👤 William H. Quick
- 👤 Rudolf R. August
- 👤 Virgil H. Strahan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:31
CPC Classifications
G; G01; G01M; G01M11/00; G01M11/08; G01M11/083; G01B; G01B11/00; G01B11/16; G01L; G01L1/00; G01L1/24; G01L1/242; G01L1/243
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
232 words
An optical sensor to provide an indication of a physical parameter, said optical sensor comprising: source means for providing a supply of incident light signals, first optical means to polarize said incident light signals, second optical means arranged so as to selectively transmit polarized light signals that are supplied thereto, at least one light transmitting optical fiber aligned at a first end thereof with each of said first and second optical means for receiving polarized incident light signals from said first optical means, light reflecting means aligned with the second end of said optical fiber to thereby reflect polarized light signals that are transmitted thereto via said optical fiber back through said optical fiber and to said second optical means, and optical detector means aligned to receive polarized output light signals that are selectively transmitted from said optical fiber through said second optical means, said detector means being responsive to the optical characteristics of the output light signals, said optical fiber undergoing a corresponding deformation in response to a physical parameter, whereby to alter the optical characteristics of the light signals being transmitted therethrough, the optical characteristics of the output light signals that are transmitted to said optical detector means through said second optical means relative to the optical characteristics of the incident light signals supplied to said optical fiber from said first optical means providing an indication of the physical parameter.
Claim 2
Dependent Claim
232 words
An optical sensor to provide an indication of a physical parameter, said optical sensor comprising: source means for providing a supply of incident light signals, first optical means to polarize said incident light signals, second optical means arranged so as to selectively transmit polarized light signals that are supplied thereto, at least one light transmitting optical fiber aligned at a first end thereof with each of said first and second optical means for receiving polarized incident light signals from said first optical means, light reflecting means aligned with the second end of said optical fiber to thereby reflect polarized light signals that are transmitted thereto via said optical fiber back through said optical fiber and to said second optical means, and optical detector means aligned to receive polarized output light signals that are selectively transmitted from said optical fiber through said second optical means, said detector means being responsive to the optical characteristics of the output light signals, said optical fiber undergoing a corresponding deformation in response to a physical parameter, whereby to alter the optical characteristics of the light signals being transmitted therethrough, the optical characteristics of the output light signals that are transmitted to said optical detector means through said second optical means relative to the optical characteristics of the incident light signals supplied to said optical fiber from said first optical means providing an indication of the physical parameter.
Claim 3
Dependent Claim
62 words
The optical sensor recited in claim 1, wherein the first end of said optical fiber comprises a relatively enlarged terminal to increase the optical coupling of light signals into and out of said fiber, said enlarged terminal having at least one flat face, and at least one of said first and second optical means positioned on the flat face of said terminal.
Claim 4
Dependent Claim
39 words
The optical sensor recited in claim 2, wherein the second end of said optical fiber comprises a relatively enlarged terminal having at least one flat face, said light reflecting means positioned on the flat face of said last-mentioned terminal.
Claim 5
Dependent Claim
28 words
The optical sensor recited in claim 1, wherein said first and second optical means include respective grating patterns that are rotated out of alignment relative to one another.
Claim 6
Dependent Claim
38 words
The optical sensor recited in claim 4, wherein one of said first or second optical grating patterns is rotated with respect to the other, so that said grating patterns are 90 degrees out of alignment with one another.
Claim 7
Dependent Claim
20 words
The optical sensor recited in claim 1, wherein each of said first and second optical means comprises a diffraction grating.
References Cited (Backward Citations)
GB1544483A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-12 | 1987-06-13 | 1987-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-12 | 1991-06-13 | 1991-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-12 | 1995-06-13 | 1995-12-13 | $7700.00 | Window Closed / Lapsed |