中文摘要：

将长周期光纤光栅（LPG）和光纤Sagnac环相结合,实现了折射率和温度的同时测量。首先利用二氧化碳激光器在保偏光纤上制作了长周期光纤光栅（PM-LPG）,然后把该PM-LPG和普通单模光纤耦合器组成Sagnac环,作为传感单元。实验选择其某一透射峰作为测试对象,其波长随温度变化,强度随折射率变化,因此可实现两个参量的同时测量。实验获得的温度灵敏度为-0.654 nm.℃-1,折射率灵敏度为49.9dB.RIU-1。整个实验系统成本低、简单实用,具有较好的应用前景。

英文摘要：

By inscribing a long-period fiber grating（LPG） on a polarization-maintaining fiber（PMF）,a fiber Sagnac loop sensor for simultaneous measurement of refractive index and temperature has been proposed and demonstrated.The LPG was fabricated on the PMF by using a CO2 laser,and then inserted into a fiber loop formed by using a normal single-mode fiber coupler.One of the transmission minimum of the Sagnac loop sensor was measured,whose wavelength varied with temperature and the intensity changed with refractive index.Temperature sensitivity of-0.654 nm·℃-1 and refractive sensitivity of 49.9 dB·RIU-1 have been achieved.The sensor system shows advantages of small size and low cost,and owns a good application prospect.