新结构D形光纤消逝场传感器  

Optical fiber evanescent field sensor based on new type D-shaped fiber

作　　者：庄须叶[1,2] 吴一辉[1] 王淑荣[1] 宣明[1] 

机构地区：[1]中国科学院长春光学精密机械与物理研究所应用光学国家重点实验室,吉林长春130033 [2]中国科学院研究生院,北京100039

出　　处：《光学精密工程》2008年第10期1936-1941,共6页Optics and Precision Engineering

基　　金：国家863高技术研究发展计划资助项目(No.2006AA04Z358);国家自然科学基金资助项目(No.60574089)

摘　　要：为提高D形光纤消逝场传感器的灵敏度并改进制作工艺,对D形光纤的结构和制作方法进行了研究。通过加大D形光纤的研磨深度,增大了传感器的有效探测面积,并使消逝场能量可以直接与被测物质作用,避免了能量耦合的损耗,提高了传感器的灵敏度。提出了采用机械研磨制作D形光纤的新方法,降低了制作成本。改进结构后,D形光纤消逝场传感器的灵敏度比旧结构传感器的灵敏度提高了3个数量级,是具有相同光程长度的直接光探测方法的1.2倍。测量亚甲基蓝时的灵敏度达到0.0435,最低测量浓度在10-7mol/L数量级,传感器的响应速度快,适合实时检测。结果表明,改进结构的D形光纤传感器灵敏度高,可以实时地反映被测物的浓度变化。In order to improve the sensitivity of D-shaped optical fiber evanescent field sensor, the construction and manufacturing methods of the sensor were studied and the construction of sensing fiber was improved. By increasing the grinding depth for D-shaped optical fiber,enlarging the effective detecting area of sensing fiber and letting the energy of evanescent wave field interact with the analyzed substance directly, the sensitivity of the sensor was improved greatly. D-shaped fiber was fabricated by a new machine grinding method,so that the quality of fiber surface was improved and the produce cost was reduced. Experimental results show that the sensitivity of new sensor has improved by three order of magnitude as compared with that of original D-shaped fiber sensor,and is about 1.2 times that of the open-path cell sensing with the same optical paths length. The sensor＇s sensitivity is 0. 043 5 when detecting methylene blue solutions, the lowest concentration can be sensed to the order 10.7 mol/L. It proves that the new sensor has a higher sensitivity and can be used in real-time detection.

关 键 词：D形光纤 光纤消逝场传感器 高灵敏度 

分 类 号：TN253[电子电信—物理电子学] TP212.2[自动化与计算机技术—检测技术与自动化装置]