OSP-A Fiber Optic Strain Gauge

Miniature, EMI/RFI and lightning immune fiber optic strain gauge

Opsens Solutions’ fabrication processes ensure an exact definition of the gauge factor, making OSP-A sensor the most accurate fiber-optic strain gauge sensor in the industry.

Combined with Opsens’ WLPI signal conditioner technology (Patent #7,259,862) and the inherent advantages of fiber optics, the OSP-A delivers unprecedented repeatability and reliability in the most adverse conditions such as high levels of electromagnetic fields as well as high voltage and rapid temperature cycling conditions.

The OSP-A uses two optical fibers that are precisely aligned inside a microcapillary tube to form an optical Fabry-Pérot interferometer. This makes the OSP-A strain gauge completely immune to any electromagnetic interference.

It is completely insensitive to transverse strains and temperatures and its micro-miniature size makes the OSP-A fiber optic sensor ideal for space-constrained applications such as intelligent load-sensing bolts and studs. Careful choice of materials for the sensor, fiber coating and cable buffering permit a high temperature operating range from -40 °C to +250 °C.

This miniature and robust fiber optic strain gauge sensor, available in different cables and sheath options, may be customized to customer specific requirements or for OEM-type applications.



  • Maintenance free without drifting over time
  • Outstanding repeatability
  • No temperature compensation required
  • Insensitive to transverse strains
  • Intrinsically safe
  • Easy to set-up and operate
  • EMI/RFI and microwave immune


  • Civil engineering and geotechnical applications
  • Marine and subsea conditions
  • High voltage environments
  • Radiated environment
  • Nuclear and hazardous environments
  • ATEX environment and zone exposed to explosive atmosphere
Measuring range (other ranges available on request)

± 1 000 µε

± 2 500 µε

± 5 000 µε

± 7 500 µε

(Extended Range Design)


0.15 µε

0.30 µε

0.75 µε

0.75 µε

Temperature sensitivity

Technology requiring no temperature compensation

Transverse strain sensitivity


Temperatures operating range

-40 °C to +250 °C (other temperatures available upon request)

EMI/RFI susceptibility

Complete immunity

Cable length

Up to 3 km (Sampling rate dependent, consult factory for more details)

Cable sheathing

From ruggedized flexible outdoor cable to robust stainless steel cable

Optical connector

SCA (Standard), SC (Standard), other connector available on request

Signal conditioner compatibility

All Opsens Solutions’ WLPI signal conditioners

Linearity, Repeatability and Hysteresis error (combined)

< 0.15%

Return to initial strain level (Lag & Latency)


Opsens Solutions Inc. reserves the right to make any changes to the above specifications without prior notice.

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