An aspheric measuring system based on master-slaved computer structure is designed. The master computer adopts industrial computer, while the slaved computer is composed of motion control card and data acquisition card. A sealer is used to detect the pulse output by the motion control cell and feedback to data acquisition cell so that the sensor realizes accurate location and high precision data acquisition. Under the basis of transforming the aspheric equation into polynomial equations, surface fitting is carried out by using of least square method. Measurement error can be reduced by increasing the amount of acquisition data. Experiment shows that the fitting accuracy estimate is less than 0. 05 jxm. The result can generally meet the precision requirement of aspheric surface machined. Data processing is programmed by Matlab. The system is characterized by simple procedure and high reliability.%基于上下位机结构设计光学非球面检验系统,采用工控机作为上位机,下位机由运动控制卡和数据采集卡构成.通过计数器协调运动控制单元和数据采集单元的动作,可实现检测过程坐标的准确定位和高精度的数据采集.对一般非球面方程进行变换后,采用最小二乘拟合算法对数据进行曲面拟合处理.并可适当增加测量点数据来减少测量误差.通过数据实验表明测量系统的拟合精度估计σ＜0.05 μm,能满足一般光学非球面的精密加工要求.系统采用Matlab进行编程,程序简单,具有较高的可靠性.
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