FOS Strain Gauge
The FOS is a Fabry-Perot fiber-optic strain gauge from Roctest, bonded to a specimen to measure its expansion and contraction from mechanical stress or thermal effects for high-performance strain measurement.
- Range
- ±1000, ±2500 or ±5000 microstrain
- Resolution
- 0.01% of full scale
- Transverse sensitivity
- <0.1% of full scale

Overview
In detail
How it works
The FOS gauge is a Fabry-Perot interferometer (FPI) that converts strain transferred from a bonded specimen into engineering units via a compatible readout system. It resists interference from fiber bending and internal creep, and the sensor is intrinsically safe and immune to lightning, EMI and RFI.
Applications
Because it is unaffected by electromagnetic interference, the FOS suits harsh environments including nuclear facilities and corrosive settings, as well as embedding within composite materials for combined static and dynamic strain measurement.
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Specifications
Technical specifications
- Range
- ±1000, ±2500 or ±5000 microstrain
- Resolution
- 0.01% of full scale
- Transverse sensitivity
- <0.1% of full scale
- Operating temperature
- -40°C to +250°C (cable and adhesive dependent)
- Gauge diameter
- 230 µm
- Gauge material
- Glass
- Connector
- ST
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