What are the advantages in using optical sensors?

Optical sensors, in particular, Fiber Bragg Grating (FBG) sensors are a choice of election if the requested number of sensors is relatively high or if the distances to and between the sensors are long. Also, for particular environments the technology may be one of the existing alternatives to conventional sensing.

Take the example of an application where distances are suited for measuring with classical strain gauges. If this application requires more than 30 sensors, it becomes cost beneficial to use optical sensors rather than conventional ones.

Moreover, the advantages inherent to the technology here may turn FBG/optical sensors as the only available or the best possible solution for certain applications.

If long distances (in the order of km) or very specific application scenarios (for example, high magnetic fields, intense EMI/RFI, risk of explosion, etc.) are to be considered, optical sensors may be the only available solution, since electrical sensors would simply fail or carry numerous problems.

Such is the case of applications in cryogenic environments which require immunity to electromagnetic effects (EMI, RFI, sparks…) and electrical isolation.

Among other long recognized advantages of FBG based sensors are:

• safe operation in potentially explosive atmospheres;
• high multiplexing capability allowing the connection of a large number of different types of sensors to a single optical fiber, reducing network and installation complexity;
• small size and weight making them suitable to hard-to-reach locations and measurement points;
• remote sensing: large distance between sensors and interrogator (several kilometers);
• no mechanical failure and high resistance to fatigue;
• ability to provide absolute measurements without the need for referencing: based on the measurement of an absolute parameter - the Bragg wavelength - independent of power fluctuations.

Learn more about HBK's Fiber Bragg Grating sensors on our website: newLight | Optical Fiber Sensor | Fiber Optic | FBG (hbm.com)