Temperature-insensitive fiber optic deformation sensor embedded in composite material

Abstract

Composite structures are made of two or more components with significantly different physical or chemical properties and they remain separate and distinct in a macroscopic level within the finished structure. This feature allows for introducing optical fiber sensors into the composite material. These sensors can demonstrate stress distribution inside tested material influenced by external tensions. In the function of the sample bend the biggest deformation is created at the surface. In the middle of the sample strain is almost equal to zero. A fiber optic sensor placed in the center of the composite material is sensitive only to temperature changes, whereas a fiber sensor placed on the surface is sensitive simultaneously to temperature and to deformations. The use of the centre fiber as a temperature compensation component is presented in this paper. © 2009 Photonics Society of Poland.