Optical stress sensing system with directional measurement capabilities
US5298964A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1992 |
| Grant date | Mar 29, 1994 |
| Priority date | — |
| Expiry date | Mar 31, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L1/241
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A stress sensor having directional measurement capabilities based on the photoelastic effect in isotropic photoelastic materials. Directional measurement capability is achieved in the sensor by the incorporation of three different optical axes passing through the photoelastic element. This creates three independent stress sensors which utilize a single sensing element. Each of the three independent stress sensors are sensitive to applied stress in different directions. The response of each of the sensors is analyzed and the magnitude and direction of incoming stress is determined. The use of a sum-difference output detection scheme results in immunity to light source intensity variations, optical fiber microbending losses, and fiberoptic connector losses. The stress sensor is immune to electromagnetic interference (EMI) and electromagnetic pulse (EMP), and is compatible with fiberoptic data transmission and control lines.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.