US4191470A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laser-fiber optic interferometric strain gauge
Assignee: Honeywell Inc
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Filing: 1978-09-18
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Granted: 1980-03-04
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Expires: 1998-09-18
Abstract
Abstract This invention is directed to a laser-fiber optic interferometric strain gauge. This is a strain gauge that can be read out by means of fiber optics, which has no power other than optical at the strain gauge. Laser light is directed into two single mode fibers, which fibers are attached to a supporting member the strain of which is to be measured. The ends of the fibers are brought into close proximity and the light coming out of the two fibers interferes. When the supporting member is strained the fringes move giving a measure of the strain.
Inventors
- 👤 Charles D. Butter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 03:10
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/16; G01B11/18; G01L; G01L1/00; G01L1/24; G01L1/242; G01L1/243
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
107 words
Optical strain gauge apparatus comprising: first and second single mode optical fibers; beam means subject to strain to be measured; means fastening portions of said first and second fibers, respectively, to different portions of said beam means; laser means positioned with respect to one end of said fibers to transmit coherent laser light through the length of said fibers; and means positioning the other end of said first and second fibers in close proximity so that the coherent laser light emanating therefrom produces an optical interference pattern, whereby when said beam means is subjected to strain said optical interference pattern changes to give a measure of strain.
Claim 2
Dependent Claim
107 words
Optical strain gauge apparatus comprising: first and second single mode optical fibers; beam means subject to strain to be measured; means fastening portions of said first and second fibers, respectively, to different portions of said beam means; laser means positioned with respect to one end of said fibers to transmit coherent laser light through the length of said fibers; and means positioning the other end of said first and second fibers in close proximity so that the coherent laser light emanating therefrom produces an optical interference pattern, whereby when said beam means is subjected to strain said optical interference pattern changes to give a measure of strain.
Claim 3
Dependent Claim
14 words
The apparatus according to claim 1 wherein said beam means are cantilever beam means.
Claim 4
Dependent Claim
21 words
The apparatus according to claim 1 wherein said different portions of said beam means are opposite sides of said beam means.
Claim 5
Dependent Claim
103 words
Optical strain gauge apparatus comprising: first and second single mode optical fibers adapted to be fastened, respectively, to different positions on strainable beam means, the different positions having different strains one from the other; laser means positioned with respect to one end of said fibers to transmit coherent laser light through the length of said fibers; and means positioning the other end of said first and second fibers in close proximity so that the coherent laser light emanating therefrom produces an optical interference pattern, whereby when optical fibers are subjected to strain said optical interference pattern changes to give a measure of strain.
Claim 6
Dependent Claim
103 words
Optical strain gauge apparatus comprising: first and second single mode optical fibers adapted to be fastened, respectively, to different positions on strainable beam means, the different positions having different strains one from the other; laser means positioned with respect to one end of said fibers to transmit coherent laser light through the length of said fibers; and means positioning the other end of said first and second fibers in close proximity so that the coherent laser light emanating therefrom produces an optical interference pattern, whereby when optical fibers are subjected to strain said optical interference pattern changes to give a measure of strain.
References Cited (Backward Citations)
US3664739A
Cited
US4163397A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-03-04 | 1983-09-03 | 1984-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-03-04 | 1987-09-03 | 1988-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-03-04 | 1991-09-03 | 1992-03-04 | $7700.00 | Window Closed / Lapsed |