一种光强差分调制MOEMS加速度计

Research of MOEMS Accelerometer With Light Intensity Differential Modulation

针对传统微光机电系统(MOEMS)光学加速度传感器结构复杂、信号解算繁琐等缺点,该文设计了一种基于绝缘衬底上的硅(SOI)片上工艺的,光强差分测量加速度的MOEMS加速度计。该传感器的主要光强调制部件为90°V型镜,在V型镜的对应位置上集成3个光纤通道,入射光经V型镜反射后进入2条输出光纤通道。加速度信号由进入2条光纤通道的光强差检测。器件的所有部分集成在单一的SOI晶圆片上,由一次深刻蚀工艺制造。与传统传感器比较,具有工艺简单、抗电磁干扰和有效抑制共模信号等优势。加速度计的性能指标:微机械灵敏度为0.077 7μm/g(g=9.8m/s^2),谐振频率为1.79kHz,传感器灵敏度为5.46mV/g。

Aiming at the disadvantages of the complicated structure and complicated signal resolution of the traditional micro-opto-electro-mechanical systems(MOEMS)optical acceleration sensor,a MOEMS accelerometer with light intensity difference for acceleration measurement based on the SOI process is designed in this paper.The main light intensity modulation component of the sensor is a 90°V-type mirror.Three optical fiber channels are integrated at the corresponding position of the V-type mirror,and the incident light is reflected into the two output fiber channels by the V-type mirror.The acceleration is detected by the light intensity difference entering the two fiber channels.All parts of the device are integrated on a single SOI wafer and fabricated by a deep etching process.Compared with the traditional sensors,the proposed sensors have the advantages of simple process,anti-electro-magnetic interference and effective suppression of common mode signals.The test results show the accelerometer has the micromechanical sensitivity of 0.077 7μm/g(g=9.8 m/s 2),the resonant frequency of 1.79 kHz,and the sensor sensitivity of 5.46 mV/g.