Optical fiber strain gauge based on a tapered single-mode fiber

A low-cost optical fiber strain gauge based on the bending of a biconically tapered single-mode fiber was fabricated. An extensive experimental study was previously performed in order to choose the best tapering on the optical fiber. With this empirical information it is possible to fit the characteristics of the gauge according to the specific application. A maximum range of 87,500 με (microstrains) with a change of 19 dB (output optical power) was obtained. This gauge has immunity to electromagnetic noise and can be applied to different types of materials such as metal, plastic even wood. In addition, other sensors like temperature or pressure sensors were also experimentally, demonstrated.