激光加工微型光纤折射率传感器的工艺与特性

Laser-Machined Miniature Fiber-Optic Refractive-Index Sensor Tip

提出一种由157nm激光制造的新型微型光纤法布里-珀罗折射率传感器的制作方法,传感头由靠近单模光纤端的具有光纤顶端微通道的法布里-珀罗空气腔组成,将单模光纤顶端的微通道作为检测介质的入口.分别在珐珀腔的反射界面镀以薄膜作为反射镜面来确保高的光对比度.试验中获得了1130.887nm/refractive-index的分辨率.和其他的光纤传感器相比,这种传感器具有体积小,结构坚固,高分辨率,线性良好,测量范围宽等优点,能够满足实际应用的要求,特别是对需要小型传感器的场合.

A novel miniature fiber-optic Fabry-Perot refractive-index sensor machined by 157 nm laser is proposed.The sensor head consists of a micro air F-P cavity near the tip of a single-mode fiber with a micro channel on the fiber tip.The micro channel is used as the entrance for medium under test.Two thin films are coated at reflective interfaces of the F-P cavity as mirrors to ensure high optical contrast,respectively.A RI resolution of 1 130.887 nm/ refractive-index unit is achieved by experiment.Compared with other fiber-optic RI sensors,the proposed sensor has a number of outstanding advantages including small,rigid,high resolution,excellent linearity,and wide measurement range,etc,which can meet the requirements for practical applications especially in biomedical diagnostic where small sensor size is essential.