D-Fiber volatile organic compound sensor

Abstract

A fiber-optic volatile organic compound sensor is described. The sensor consists of a single-mode D-fiber with a polydimethylsiloxane layer. The polydimethylsiloxane layer is applied to the fiber flat after removal of a section of the fiber's supercladding in order to increase evanescent interaction of the light with the layer. Absorbance of volatile organic compounds alters the refractive index of the layer, resulting in a birefringent change. This change is observed as a shift in polarization of the light carried by the fiber. Sensor response is observed for dichloromethane and acetone in gas and liquid concentrations respectively.