【作者】 张昊； 刘波； 贾承来；

【Author】 Zhang Hao Liu Bo Jia Chenglai (Key Laboratory of Opto-Electronic Information and Technology,Ministry of Education,Institute of Modern Optics,Nankai University,Tianjin 300071,PR China)

【机构】 南开大学现代光学研究所,光电信息技术教育部重点实验室；

【摘要】 介绍了一种基于多纵模分布布喇格反射(DBR)光纤激光器拍频解调的新型光纤折射率测量方法。利用拍频解调的原理,通过对激光器相邻纵模间拍频的观测实现了对光纤折射率的测量,该方法具有实验装置易于实现、同传统的波长解调方式相比解调成本低等优点。本文对这种新型的光纤折射率测量方法进行了理论分析与实验论证,通过利用等强度梁对激光器的谐振腔施加应变,实验上测量了不同应变下的光纤折射率。实验结果表明光纤折射率随应变的增加线性减小,其拟合度达到了0.9971,光纤折射率的应变系数约为-6.3086×10-7/με,其测量结果与国内外的前期相关研究结果一致,说明本文测量方法的可靠性。更多还原

【Abstract】 A novel method for fiber refractive index measurement based on beat frequency interrogation of the multi-longitudinal-mode distributed Bragg reflector (DBR) fiber laser is presented.Based on beat frequency interrogation,measurement of fiber refractive index has been achieved through monitoring the beat note between adjacent longitudinal modes.The proposed measurement method has several advantages such as simple structure,and,compared with the conventional wavelength interrogation approach,low system cost,etc.In this paper,this novel method for measurement of fiber refractive index has been theoretically and experimentally investigated.By utilizing an uniform cantilever beam (UCB) to apply strain on the oscillation cavity,strain dependence of fiber refractive index has been measured.Experimental results indicate that fiber refractive index linearly decreases as strain increases,and its coefficient of determination reaches 0.9971.The strain coefficient of fiber refractive index is about-6.3086×10-7 /με,basically in agreement with earlier related studies,which proves the reliability of this proposed approach.更多还原