Norwegian fiber optic sensors include Distributed Acoustic Sensing (DAS), Distributed Temperature Sensing (DTS), Distributed Strain Sensing (DSS), and specialized chemical and current sensors, each designed for precise monitoring in diverse applications.

Distributed Acoustic Sensing (DAS)

DAS technology is widely used in Norway by institutions like NORSAR and NORCE. It utilizes fiber optic cables to detect vibrations along the cable length, converting laser backscatter signals into spatially resolved measurements. DAS can monitor pipelines, railways, highways, and natural hazards such as avalanches or rockslides. It allows continuous vibration localization with high spatial resolution, often down to one meter over distances up to 150 km, and supports automated data processing and alarm systems .

Distributed Temperature Sensing (DTS)

DTS systems measure temperature along the entire length of an optical fiber. Norwegian research groups employ Raman DTS and Fiber Bragg Grating (FBG) arrays for applications including geothermal energy, industrial process monitoring, pipeline leakage detection, and high-voltage cable monitoring. DTS offers long-distance measurement capabilities, high spatial resolution, and suitability for harsh or electrically sensitive environments .

Distributed Strain Sensing (DSS)

DSS technology measures strain along structures such as bridges, mountainsides, and seabeds. NORCE uses DSS for monitoring natural hazards like rockslides and avalanches, providing early warning and structural health insights. DSS is particularly valuable for large-scale infrastructure monitoring where conventional sensors are impractical .

Chemical and Water Sensing

NORCE has developed systems like ODIMS for distributed water and humidity measurement, targeting corrosion under insulation (CUI) and industrial process monitoring. Ongoing research aims to expand these sensors to detect chemical leaks, including CO2 leakage from pipelines or geological storage sites, enhancing environmental and industrial safety .

Fiber Optic Current Sensors

These sensors measure electrical currents using the Faraday Effect, detecting polarization changes in light caused by magnetic fields. They are highly immune to electromagnetic interference, operate non-contact, and are used in power generation, oil and gas, telecommunications, and aerospace applications. Norwegian research leverages these sensors for precise monitoring in electrically noisy or high-voltage environments .

Sensor Classification

Fiber optic sensors can also be categorized by their construction:

• Intrinsic sensors: The fiber itself acts as the sensing element, directly affected by the measurand.
• Extrinsic sensors: The fiber transmits light to and from an external sensing element.
• Hybrid sensors: Combine intrinsic and extrinsic elements for enhanced functionality . These Norwegian-developed fiber optic sensors are applied across energy, transportation, environmental monitoring, and industrial sectors, demonstrating versatility, high sensitivity, and suitability for challenging conditions.