Progress toward a large-area chemical sensor

Pacific Northwest National Laboratory is developing a large- area, fiber-optic chemical sensor that combines chemically selective coatings and optical spectroscopy. This is a potentially hyphenated sensing technique because of the ability to collect broadband spectroscopic information in addition to sensing the quantity of the target species. Selective compound coating of optical waveguides enables the production of chemical sensors in large lot sizes. This paper describes the progress to date to produce iodine vapor selective fiber sensors that use through the fiber absorption spectroscopy. Spectra have been collected on uncalibrated I2/N2 gas mixtures using visible light.