Laser & Optoelectronics Progress, Volume. 55, Issue 3, 030602(2018)
Central Wavelength Interrogation Method of Ultra-Short FBG by Dual-Wavelength Laser
To realize the demodulation of the fiber grating center wavelength, we fabricate an ultra-short fiber Bragg grating (US-FBG), with grating length of less than 1 mm, reflectivity of over 60%, 3 dB bandwidth of more than 1.5 nm, and the edge linear region of the reflection spectrum of more than 1.5 nm. We use US-FBG as the sensing element, and propose a central wavelength interrogation method based on dual-wavelength laser. When the frequency stabilized laser with the central wavelength in the spectral linear region is incident on the US-FBG, the reflected optical power changes linearly with the drifts of the US-FBG spectrum, whose linearity is 0.998. In order to make full use of the linear region on the two sides of reflection spectrum, we use the complementary interrogation method with dual-wavelength lasers to extend the wavelength demodulation range to 3 nm. The measured values are in great agreement with the actual values. The method has the advantages of simple structure, low power consumption, and high spatial resolution.
Get Citation
Copy Citation Text
Kai Li, Jingtao Xin, Fei Luo, Xiaoping Lou, Lianqing Zhu. Central Wavelength Interrogation Method of Ultra-Short FBG by Dual-Wavelength Laser[J]. Laser & Optoelectronics Progress, 2018, 55(3): 030602
Category: Fiber Optics and Optical Communications
Received: Aug. 25, 2017
Accepted: --
Published Online: Sep. 10, 2018
The Author Email: Zhu Lianqing (zhulianqing@sina.com)