| Title |
Unambiguous Fiber Fabry-Perot Temperature Sensor by an Additional Partial Mirror |
| Authors |
김광수(Kim, Gwang-Su) ; 이홍식(Lee, Hong-Sik) |
| Keywords |
Fiberoptic sensor ; temperature sensor ; fiber Fabry-Perot interferometry ; phase modulation ; TiO_2 coating |
| Abstract |
The fiber Fabry-Perot interferometric(FFPI) sensor is well known in the field of industrial diagnosis due to its outstanding properties such as tiny size, simple and rugged structure, and easy interrogation. As other fiber interferometric sensors, it also suffers from ambiguous output caused by highly periodic feature in its optical transfer function. In most cases, the ambiguity leads to relatively short dynamic operating range and long processing time during power-on reset, which limits its application to some specific fields requiring very high resolution. In this paper a method based on double sensing scheme was proposed to overcome the above difficulty. By employing a fringe selection auxiliary FFPI sensor the original FFPI sensor can identify its true position on the phase domain. The performance test with 10mm FFPI sensor and a thermocouple temperature sensor for reference shows wide dynamic range 0-900l keeping a reasonable resolution of 0.1l over the entire range. |