Fiber optic acoustic sensor with specifically selected flexural disks
US6496264B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 2000 |
| Grant date | Dec 17, 2002 |
| Priority date | — |
| Expiry date | Jan 16, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01H9/004
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A displacement sensor and an acceleration sensor are mounted to a common support member. The displacement sensor comprises a first circular flexural disk having a natural frequency less than the frequency range of the acoustic waves of interest. Spiral-wound optical fiber coils are mounted to opposite sides of the first flexural disk. The acceleration sensor comprises a second flexural disk having a natural frequency greater than the frequency range of the acoustic waves. Spiral-wound optical fiber coils are mounted to opposite sides of the second flexural disk. A fiber optic interferometer provides an output signal that is a combination of signals output from the displacement sensor and the acceleration sensor. The displacement sensor includes an inertia ring mounted to an edge of the first flexural disk to keep it nearly stationary when an acoustic wave in the selected frequency range is incident upon the housing. The flexural disks include upper and lower rings spaced apart from the support post with portions of the disks between the rings and the support post defining hinges at which the flexural disk flex in response to acceleration of the support member along its longitudinal…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.