基于M-Z动态干涉仪的全光纤麦克风研究

Theoretical and Experimental Research of All-Fiber Microphone Based on M-Z Interferometer

设计了一种新型的全光纤干涉型型麦克风.通过构造由光纤耦合器和镀铝振膜组成的动态M-Z干涉光路,将外界声压对振膜的作用转化为对光路相位的调制,得到的输出光信号光电转换后可直接提取出原声音信号.整个光路和光纤探头部分无任何电的参与,具有抗电磁干扰、尺寸小、灵敏度高等优点.并通过实验对该光纤麦克风进行了测试,得到了较好的实验结果.

A design is proposed for an all-fiber microphone which utilizes optical interference to sense the sound-induced motion of a thin diaphragm. The microphone operates on the well known principle of M-Z interferometer made up of fiber couplers and diaphragm to get the original acoustic signal. The microphone membrane is the only metallic part in the microphone. The quantity of aluminium on diaphragm is so small that the microphone does not feel any of electrical, magnetic, electromagnetic and high frequency radio fields. The measured signals were compared to original signals. The test results indicate that the function of fiber optic microphone is satisfying.