Abstract
An improved peak-to-peak method is developed for interrogating the absolute cavity length of fiber optic extrinsic Fabry–Perot interferometric (EFPI) sensors with high resolution. A fiber Fabry–Perot tunable filter (FFP-TF) is used to scan the optical spectrum of an EFPI, and the problems caused by the nonlinear performance and poor repeatability of the FFP-TF are removed by using a wavelength calibration technique. A linear fitting is used to calculate the wavelength spacing between two adjacent apexes in the optical spectrum, and the cavity length can be retrieved using this wavelength spacing. The experimental results show that the measuring resolution is improved from 25 to , and a linear output is also obtained.
© 2008 Optical Society of America
Full Article | PDF ArticleMore Like This
Hongchun Gao, Yi Jiang, Liuchao Zhang, and Lan Jiang
Appl. Opt. 57(5) 1168-1173 (2018)
Nikolai Ushakov and Leonid Liokumovich
Appl. Opt. 53(23) 5092-5099 (2014)
Jiawei Mei, Xiaosheng Xiao, and Changxi Yang
Appl. Opt. 54(12) 3677-3681 (2015)