Wong Allan C L, Chung W H, Tam Hwa-Yaw, Lu Chao
Photonics Research Centre, Department of Electronic and Information Engineering, Hong Kong Polytechnic University, Kowloon, Hong Kong.
Opt Express. 2011 Jan 17;19(2):409-14. doi: 10.1364/OE.19.000409.
A type of fiber laser, called tilted Bragg reflector fiber laser (TBR-FL), is proposed and its application in simultaneous sensing of surrounding refractive index (SRI) and temperature is demonstrated. This FL is formed by a pair of wavelength and tilt-angle matched tilted fiber Bragg gratings (TFBGs) that acted both as a resonant cavity and sensing element. A unique spectral feature of the TBR-FL is the presence of grating tilt-induced cladding modes spectrum that does not appear in other type of FL, which provides an extra sensing mechanism. By employing a simple experimental setup with the discrete wavelet transform as the demodulation technique, simultaneously sensing of SRI and temperature are achieved by measuring and analyzing the wavelet coefficients shifts of the laser output and averaged cladding modes.
提出了一种称为倾斜布拉格反射器光纤激光器（TBR-FL）的光纤激光器，并展示了其在同时传感周围折射率（SRI）和温度方面的应用。这种光纤激光器由一对波长和倾斜角匹配的倾斜光纤布拉格光栅（TFBG）构成，它们既作为谐振腔又作为传感元件。TBR-FL的一个独特光谱特征是存在由光栅倾斜引起的包层模光谱，这在其他类型的光纤激光器中并不出现，它提供了一种额外的传感机制。通过采用以离散小波变换作为解调技术的简单实验装置，通过测量和分析激光输出及平均包层模的小波系数偏移，实现了对SRI和温度的同时传感。
