Title :
Abrupt Taper Michelson Interferometer Using Heterodyne for Measuring Refractive Index
Author :
Yu-Chan Liang ; Chia-Chi Liao ; Yu-Lung Lo
Author_Institution :
Dept. of Mech. Eng., Nat. Cheng Kung Univ., Tainan, Taiwan
Abstract :
A method is proposed for measuring the refractive index (RI) of aqueous solutions using an abrupt taper Michelson interferometer and a synthetic heterodyne detection scheme. In the proposed approach, the abrupt taper Michelson interferometer is implemented with a Fabry-Perot cavity in a path-matching differential interferometer. The RI of the aqueous solution is then extracted from the phase shift of the heterodyne demodulated interferometric signal. The experimental results show that a change in the RI of 0.0001 prompts a phase shift of sim 1.35° in the demodulated signal given the use of an abrupt taper Michelson interferometer with a sensing length of 20 cm.
Keywords :
Fabry-Perot interferometers; Michelson interferometers; demodulation; fibre optic sensors; heterodyne detection; optical phase shifters; optical signal detection; refractive index; refractive index measurement; Fabry-Perot cavity; abrupt taper Michelson interferometer; aqueous solutions; heterodyne demodulated interferometric signal; path-matching differential interferometer; phase shift; refractive index measurement; synthetic heterodyne detection scheme; Fabry-Perot; Optical fiber amplifiers; Optical fiber sensors; Optical interferometry; Phase shifting interferometry; Refractive index; Refractive index; abrupt taper Michelson interferometer; heterodyne modulation; path-matching differential interferometer;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2014.2355262
