一种硅微机械谐振器的单光源激振测振方法

A Single Optical Source System for Exciting and Detecting the Vibration of Silicon Microresonator Sensors

提出一种用于硅微机械谐振传感器研究的单光源激振测振新方法,即微谐振器的激励及其谐振信号的测量使用同一光源。该方法采用全光纤斐索干涉仪结构,将干涉信号与光源强度变化信号进行运算后,通过选频技术解调出谐振器的振动信息,同时采用贝塞耳函数比值法扩大了振动幅度的测量范围,省去了一些难以获得准确数值的工作参数的计算。采用该方法实现了微悬臂梁结构形式的谐振器件的单光源激振与测振,获得了器件的谐振频率约为8.81kHz以及谐振状态下的振动幅度约为135nm。实验结果与采用其他双光源激振测振方法基本一致,新方法的可行性得到了验证。

A novel method for exciting and detecting vibration of silicon mieroresonator sensors is presented. A single laser diode is used for excitation and detection, and an all-fiber Fizeau interferometer is applied. The displacement signal of microresonator is demodulated from the interference signal, which is modified with the intensity change of the laser diode. The Bessel function ratio method is used to enlarge the measurement range. And some working parameters need not be measured. Using this method the resonance frequency about 8.81 kHz and the tested cantilever amplitude at resonance about 135 nm were obtained. The experimental results are consistent with those of other method, so practicability of the new method is proved.