Review of emitters and detectors for optical gas and chemical sensing

This paper presents the results of a survey commissioned by the Optical Sensors Collaborative Association (OSCA) to identify sources and detectors in the wavelength region 250 nm to 5 micrometers , greater emphasis being placed on low cost devices e.g., LEDs and semiconductor lasers, which could form the basis of low to medium cost, general purpose instrumentation. The survey reviews both commercial availability and near term research activities and concludes that while emitters are available across the entire spectral range of interest, and indeed tunable emitters cover the entire range, few low cost devices are currently commercially available. Detectors are available to cover the entire range available, but little novelty was identified except for the inclusion of thermoelectric coolers within device packages and in the area of pyroelectrics.