A 2-channel embedded infrared fiber-optic temperature sensor was fabricated using two identical silver halide optical fibers for accurate thermometry without complicated calibration processes. In this study, we measured the output voltages of signal and reference probes according to temperature variation over a temperature range from 25 to 225 °C. To decide the temperature of the water, the difference between the amounts of infrared radiation emitted from the two temperature sensing probes was measured. The response time and the reproducibility of the fiber-optic temperature sensor were also obtained. Thermometry with the proposed sensor is immune to changes if parameters such as offset voltage, ambient temperature, and emissivity of any warm object. In particular, the temperature sensing probe with silver halide optical fibers can withstand a high temperature/pressure and water-chemistry environment. It is expected that the proposed sensor can be further developed to accurately monitor temperature in harsh environments.
Lee, B; Cho, DH; Tack, G-R; Chung, S-C; Yi, JH; Jun, JH; Son, S; Cho, S. Feasibility study of development of plastic optical fiber temperature sensor using thermosensitive clouding material. Jpn. J. Appl. Phys 2006, 45, 4234–4236.
Fernandez-Valdivielso, C; Egozkue, E; Matias, IR; Arregui, FJ; Bariain, C. Experimental study of a thermochromic material based optical fiber sensor for monitoring the temperature of the water in several applications. Sens. Actuat. B 2003, 91, 231–240.