Optical strain gauges are strain sensors based on optical fibers. There are several optical technologies that fit the same classification, but this article focuses on Fiber Bragg Grating (FBG) based sensors – a technology embraced by HBK. FBGs are primarily used to measure strain, but can easily be integrated into different types of transducers, such as temperature, acceleration or displacement transducers.
Compared to traditional electrical strain gauges, optical strain gauges do not need electricity. Instead, the technology is based on light that propagates through a fiber. The sensors are, therefore, completely passive and immune, for example, to electromagnetic interference. This is just one of the reasons why optical strain gauges are superior to electrical ones in certain applications.