Optical-fiber arrays for vapor sensing

This paper reviews the use of optical fibers as a platform to fabricate vapor sensitive arrays that have been developed in the authors’ laboratory in recent years. Two types of fluorescence-based optical-fiber array systems are described: polymer-coated single core optical fibers and imaging fiber-optic bundles incorporating functionalized microspheres. Each system responds to an analyte vapor in a cross-reactive manner generating a multi-dimensional signal that can be used to train a pattern recognition program to identify subsequent exposures of the array to learned vapors. Several applications are described including explosives and nerve agent detection as well as the detection of several volatile organic compounds and ignitable liquids.