为了优化基于侧边抛磨光纤器件的性能，采用在线抛磨和测量的方法，实验研究了抛磨区长度和抛磨区剩余包层厚度对侧边抛磨光纤折射率传感特性的影响.研究发现，侧边抛磨光纤对材料折射率的传感特性依据灵敏度可以分为三个区域：1)折射率在1.300～1.450范围内，传感特性的灵敏度很低,但线性度很好；2)折射率在1.450～1.500范围内，具有灵敏的传感特性，但在这个范围内线性度较差；3)折射率液大于1.500以后，可以同时获得较好的灵敏度、线性度和稳定性.比较抛磨区长度分别为10 mm和20 mm的侧边抛磨光纤，20 mm的抛磨区长度不会提高传感的灵敏度，却会增加器件的不稳定性.抛磨光纤剩余包层厚度对传感灵敏度和功率损耗有重要影响，可依据器件实际需要选择合适的剩余包层厚度.

In order to optimize the performance of optical devices fabricated with side-polished fibers, online polishing and measurements were conducted to study sensing characteristics of side-polished fiber effected by polishing length and remaining cladding thickness. The results show that, the sensing characteristics for the side-polished fiber used here can be divided into three regions according to its sensitivity. In the first region with refractive index ranging from 1.300 to 1.450, low sensitivity and high linearity were achieved. In the second region with refractive index ranging from 1.450 to 1.500, high sensitivity can be obtained, while very low stability. Compared to the first two regions, both relatively good sensitivity, linearity and stability can be spontaneously achieved in the third region with refractive index higher than 1.50. Comparisons of fibers with polishing length of 10 mm and 20 mm show that the increase of polishing length do not result in improvement of sensitivity, while a loss in stability. The remaining cladding thickness plays an important role in determinating the sensitivity and the insert loss of side-polished fiber, therefore it should be optimized to achieve the desired sensors.