弯曲致受抑全内反射式液位检测效应仿真实验分析

Analysis and Research of Bending-caused Frustrated Total Internal Reflection Liquid Level Detection Simulation and Experimental

从传统的有损光纤结构的液位传感方法入手,深入研究塑料多模光纤传输过程中的包层模式下的弯曲损耗、受抑全内反射以及光能量耦合机理,在理论上揭示传感器效应的作用机制,从几何光学的理论出发,使用光线追迹方法,进一步模拟宏弯曲光纤内的光线传播路径,光纤受抑全内反射效应的能量变化机制,仿真结果与理论分析一致,搭建实验平台对前述理论分析和仿真模拟结果进行进一步的测试和验证。实验结果表明,该效应相对于传统有损光纤结构方法,可以进行高精度高灵敏度的稳定可靠液位传感测量。

The paper firstly analyzes the liquid level sensing method which may damage optical fiber structure,researching the bending loss,frustrated total internal reflection,and light energy coupling mechanism under cladding mode of multimode in the process of fiber transmission.Theoretically,the paper demonstrates the mechanism of sensor effect. Then,it simulates the light transmission route in macro bending fiber and the energy changing mechanism of fiber frustrated total internal reflection. It is showed that the simulation results are in accordance with the former theoretical analysis. Then,further test is conducted to demonstrate whether the former theory accords with the simulation results. The result shows that frustrated total internal reflection liquid level detection is available compared to the old liquid level sensing method that may bring damage to optical fiber structure.