Low-temperature measurement by using IR TeX glass fibers

The TeX glass optical fibers have been developed for their broad transparency in the 3 to 13 micrometer region and their good thermal, mechanical and chemical properties. The minimum losses of these fibers are approximately 0.5 dB/m in the mid-IR domain of 7 - 9 micrometer. Owing to these properties, these fibers are useful in a wide range of applications, requiring a relatively low power level, such as temperature sensing. Temperature measurements using a TeX glass fiber have been investigated. The set-up was mainly composed of a polymer-coated fiber which transmitted the signal of a black body to a HgCdTe detector. Fibers with different lengths and different diameters have been used for this experiment and the temperature sensing has been performed in the region of minus 30 degrees Celsius up to 400 degrees Celsius. It has been found that the signal transmitted to the detector increases very rapidly when the temperature is higher than 60 degrees Celsius. However, the sensitivity of the used set-up is still high, even at temperatures as low as minus 30 degrees Celsius. The resolution of the sensor is estimated to be better than 1 degree Celsius in the region of room temperature. These fibers provide a possibility of non-contact low temperature sensing.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.