高灵敏温度自补偿折射率传感器的研究

Research on temperature self compensated high sensitivity refractive index sensor

测量折射率时为同时达到高灵敏度和温度补偿的测量效果,提出一种环境折射率(RI)传感器。传感部分基于重叠级联结构的长周期光纤光栅(LPFG),通过寻找特定的光栅周期,使一阶9次、11次包层模的损耗峰分别向一短一长两个波长方向漂移,以其相对漂移量来解调折射率。仿真结果表明,该传感器与普通的温度补偿折射率传感器相比,折射率灵敏度明显提高,在生物、化工领域有较好的实用价值。

This paper puts forward such a kind of environmental optical fiber refractive index（RI） sensor which the sensing system is based on the overlapping cascade long-period fiber grating,and it can provide temperature self compensation during measurement.Though finding specific grating period,it can make the resonant wavelength of loss peak which was coupled out by the cladding mode including order 9 and order 11 in the cascade, and the drifting of wavelength that has an opposed direction with the changes of outside refractive index, demodulating the index of refraction with their relative drift. The emulation shows that, making comparison with the normal sensor of temperature compensation refractive index, the sensitivity of refractive index has an obvious improvement, so it has a better practicability.