基于光纤光栅的温度不敏感光学麦克风

A FBG-based temperature insensitive optical microphone

研制了一种基于光纤光栅的温度不敏感型光学麦克风。该麦克风由振膜传感声波信号,由一对匹配光栅来实现波长调制解调的功能,同时匹配光栅还可作为温度补偿的装置。从理论上解释了匹配光栅温度补偿的原理。实验证明,这种光学麦克风不仅能够获得稳定的传声效果,而且表现出较宽的频率响应范围（400-2 100Hz）和平坦程度,并且静态输出光功率随外界温度变化仅为0.0233 dBm/℃,表现出对温度的不敏感性。

A FBG-based fiber optical microphone which is insensitive with temperature and has a broad frequency band（400-2 100 Hz） is described.The fiber optical microphone is composed of a Broad Band Source（BBS）,a pair of matched fiber Breagg Gratings（FBG） and a polyester diaphragm which can vibrate with acoustic waves.The pair of matched FBGs is employed for both wavelength demodulation and temperature compensation.The features make the fiber optical microphone achieve a stable operation,and make the optical microphone temperature insensitive.It has been proved theoretically and experimentally.The experimental results show that the devices have a 400-2 100 Hz of frequency response range and the temeprature insensitivity of 0.023 3 dBm/℃.