七芯光纤三通道分段检测SPR传感技术研究

Optical fiber SPR sensor is the natural extension of the development of the sensing technology and the system miniaturization in the future. However, the optical fiber SPR sensor has not yet commercially, there is no effective solution for the two bottleneck problems of low sensitivity and it is difficult to achieve multi-channel detection. Based on the previous research of optical fiber SPR sensor ,we propose a three-channel segmented detection SPR sensor ,this three-channel SPR sensor uses circularly symmetric distributed six cores to couple light into and out to realize the three channels SPR sensing and testing by fiber-end grinding technology, which is the first time to realize the reflective type optical fiber SPR sensor based on time-division multiplexing (TDM) technology. After the further study of the relationship among the factors of grinding angle,the refractive index waiting for testing,sensitivity and the detection range,a novel SPR segmented detection technology is proposed.We employ the three sensing channel of the seven-core fiber to realize a fiber SPR sensor with wider detection range and higher sensitivity whose refractive index range is 1.333-1.395, testing average sensitivity is above 7000nm/RIU,bandwidth is within 250nm.The parameter index in this research has already reached or even beyond the commercialized prism type SPR sensor which employed the theoretical innovation and technological progress of microstructure multicore fiber SPR sensor.

光纤表面等离子体共振（SPR）传感器是今后SPR传感技术发展和系统微型化的自然延伸，但光纤型SPR传感器尚未商业化，存在灵敏度低、实现多通道测量困难两大瓶颈问题尚无法有效解决。本项目研究团队在前期纤维集成SPR传感器研究工作基础上，提出七芯光纤三通道分段检测SPR传感器，采用裸光纤端面研磨技术将七芯光纤加工成对称三对锥角结构，构成三传感通道，将首次实现光纤型SPR反射式时分复用技术。并在深入研究研磨角度、待测折射率、灵敏度、检测范围四因素间相互制约关系基础上，提出新颖的SPR分段检测技术，利用七芯光纤三传感通道，实现折射率检测范围1.333-1.395，平均灵敏度实验值7000nm/RIU以上，工作带宽250nm以内的新一代超宽检测范围超高灵敏度光纤型SPR传感器。推动光纤型SPR传感器指标达到甚至超越已商用化的棱镜型SPR传感器水平，实现微结构多芯光纤SPR传感器的理论创新和技术进步。

光纤表面等离子体共振（SPR）传感器是今后SPR传感技术发展和系统微型化的自然延伸，但光纤型SPR传感器尚未商业化，存在灵敏度低、实现多通道测量困难两大瓶颈问题尚无法有效解决。本项目提出七芯光纤三通道分段检测SPR传感器，基于裸光纤研磨技术，利用七芯光纤呈环形对称分布的六个纤芯，每组对称的两个纤芯为一组进行研磨镀膜并注光，构成三传感通道，首次实现光纤型SPR反射式时分复用技术。并在深入研究研磨角度、待测折射率、灵敏度、检测范围四因素间相互制约关系基础上，提出SPR分段检测技术，利用七芯光纤三传感通道，实现了在1.333-1.395大检测范围内，平均灵敏度达7387.1nm/RIU，最高灵敏度达8502.5nm/RIU，工作带宽仅需250nm的新一代超宽检测范围超高灵敏度光纤型SPR传感器。推动光纤型SPR传感器指标达到甚至超越已商用化的棱镜型SPR传感器水平，实现微结构多芯光纤SPR传感器的理论创新和技术进步。本项目实现的多通道传感器可用于混合物测量和去除非特异性干扰。此外，本项目实现的七芯光纤反射式结构，探针直径仅125μm，有望插入血管进行在线监测。