基于SPR的双锥形光纤折射率传感特性研究

Research on Refractive Index Sensing Properties of Bioconical Optical Fiber Based on SPR

利用液体折射率与表面等离子共振技术（SPR）,研究了光纤传感器在液体中透射光功率的变化,提出了一种液体折射率光纤传感器。该传感器采用3 d B耦合器进行分光,利用输出波长范围为1 530-1 580 nm的ASE作为光源,以熔融拉锥光纤作为传感单元。利用该光纤传感器,对Na Cl溶液浓度与透射光功率之间关系的进行了实验研究。研究结果表明传感器外部介质折射率越高,光的传输损耗越大。而且在锥区外部镀膜,能够有效地提高传感器的灵敏度。

The change of transmission optical power of optical fiber sensor in the liquid was studied and the liquid refractive index optical fiber sensor was proposed. The sensor used a 3 d B coupler to divide light. The wavelength of the light source ASE ranged from 1 530 nm to 1 580 nm. The fused taper fiber was used as sensing unit. The relationship between the light power of the transmission spectrum and the Na Cl solution concentration was analyzed by using the optical fiber sensor. The results show that the higher the refractive index of the sensor external medium is,the bigger the transmission loss is. And coating on the outside of the cone can effectively improve the sensitivity of the sensor.