A novel microbending optical fiber temperature sensor

This paper presents a novel temperature sensor based on bimetallic strip and optical fiber microbending loss. A bimetallic strip is a mechanical temperature sensor element, is simply constructed from two strips of different metals with different thermal linear expansion coefficient bonded together. A fiber is distorted in a deformer by pressing it between grooved plates. One end of the bimetallic strip is welded on a fixed framework, the other end performed upon the deformer, and form a microbending optical fiber temperature sensor. When the temperature changes, the thermo static bimetallic strip deforms, and causes grooved plates having a displacement according to the temperature changes, and modulates light loss in fiber. The measuring results show measuring range comes to around 100°C with high accuracy and linearity.