微电子机械系统中转速测量的光学方法

Measurement of Angular Velocity in MEMS by Optical Method

利用显微测量技术和CCD图像传感器的线性积分成像特性,将数字图像处理技术与时间积分成像技术用于微电子机械系统(MEMS)中的转速测量。只需分别摄取被测物体上的标志点在静止状态下的时间积分图像和运动状态下的时间积分图像,即可测得物体在该段曝光时间内的转速。该方法对实验设备及实验条件要求较宽松。实验表明该方法对微系统中近似匀速转动时转速的测量是完全可行的,且具有较高的精度。

This paper presents a non-osculant method which can be used to measure angular velocity in MEMS. On the basis of microscopic display measurement techniques, CCD linearintegral imaging characteristics, the digital image processing technology and time-integral imaging theory. In the experiments, the angular velocity of a body in MEMS in the interval of time-exposure were determined by capturing the time-integral pictures of the body′s marks both in the static state and in the motion state. According to characteristics of the CCD, the relation to the gray′s integral and the time of exposure is linear;the relation to the gray and the count backwards of the track′s length is also linear;and the relation to the track′s length and the angular velocity is linear. Then the angular velocity is determined by tracks of the body′s marks in the pictures and the time of exposure. The equipments used in the experiments are simple and the requirements of experiments are low. Experimental results show that the method can be applied to determine the angular velocity in MEMS reliably and accurately.