Title :
Wide-Range Displacement Sensor Based on Fiber-Optic Fabry–Perot Interferometer for Subnanometer Measurement
Author :
Zhou, Xinlei ; Yu, Qingxu
Author_Institution :
Sch. of Phys. & Optoelectron. Technol., Dalian Univ. of Technol., Dalian, China
fDate :
7/1/2011 12:00:00 AM
Abstract :
A displacement sensor with subnanometer resolution based on the fiber-optic Fabry-Perot interferometer is proposed. The Fabry-Perot cavity is formed between the fiber end face and a high reflectivity mirror, which effectively improved the contrast of the interference fringe. Meanwhile, since the measuring range and the demodulate resolution for Fabry-Perot sensor are difficult to be improved simultaneously, a novel demodulation method based on the combination of the Fourier transform method and the minimum mean square error estimation-based signal processing method has been presented, which is capable of providing subnanometer resolution and absolute measurement over a wide dynamic range. The experimental results show that the resolution of the sensor is up to 0.084 nm over a dynamic range of 3 mm.
Keywords :
Fabry-Perot interferometers; Fourier transforms; displacement measurement; fibre optic sensors; optical scanners; Fourier transform method; fiber-optic Fabry-Perot interferometer; high reflectivity mirror; mean square error estimation-based signal processing method; subnanometer measurement; wide-range displacement sensor; Confocal laser scanning microscope; large measurement range; nano-displacement measurement; spectrum demodulation;
Journal_Title :
Sensors Journal, IEEE
DOI :
10.1109/JSEN.2010.2103307