We propose a new wavelength-division-multiplexing method for extrinsic fiber Fabry–Perot interferometric (EFPI) sensing in a polarized low-coherence interferometer configuration. In the proposed method, multiple LED sources are used with different center wavelengths, and each LED is used by a specific sensing channel, and therefore the spatial frequency of the low-coherence interferogram of each channel can be separated. A bandpass filter is used to extract the low-coherence interferogram of each EFPI channel, and thus the cavity length of each EFPI channel can be identified through demultiplexing. We successfully demonstrate the simultaneous demodulation of EFPI sensors with same nominal cavity length while maintaining high measurement precision.
© 2013 Optical Society of America
Instrumentation, Measurement, and Metrology
Original Manuscript: July 22, 2013
Revised Manuscript: August 22, 2013
Manuscript Accepted: August 22, 2013
Published: September 19, 2013
Jinde Yin, Tiegen Liu, Junfeng Jiang, Kun Liu, Shuang Wang, Fan Wu, and Zhenyang Ding, "Wavelength-division-multiplexing method of polarized low-coherence interferometry for fiber Fabry–Perot interferometric sensors," Opt. Lett. 38, 3751-3753 (2013)