基于线阵CCD的高精度位移传感器前端设计

Front-end design of high precision displacement sensor based on linear array CCD

为了实现对微小位移的高精度非接触测量,设计了一种基于线阵CCD的高精度位移传感器前端模块。运用激光三角测量法设计了光学镜头,利用FPGA产生线阵CCD所需的驱动时序,CCD输出的一维视频信号经过前置电路处理后得到稳定的模拟信号,供数字电路进行处理。系统具有结构简单、体积小、输出信号稳定、分辨率高、测量精度高等特点。实验测试表明,该传感器前端模块输出模拟信号稳定,干扰小,计算得到最大量程为±15 mm,精度可达到20?m,能广泛应用于微小位移的精密测量。

In order to achieve the high-precision non-contact measurement for tiny displacement, a high-precision displacement sensor front-end module is designed based on linear array CCD. An optical lens is designed using the principle of laser triangulation, and the system uses the FPGA to generate the drive timing required for the linear array CCD. The one-dimensional video signal output by CCD is handled to obtain a stable analog signal through the front circuit, and the signal is available for digital circuitry. The system has the characteristics of simple structure, small volume, stable output signal, high resolution and high precision. Experimental tests show that the sensor front-end module outputs are stable with small interference analog signal after calculation, the maximum range is ±15 mm, and the accuracy can reach 20 ？m. The system can be widely used in the precise measurement of tiny displacement.