激光衍射对刀是通过检测两个一级衍射条纹峰值点的间距来进行对刀间隙测量的一种方法。测量过程中众多工艺参数的调整会对测量结果的精度产生重要影响。由于CCD装夹误差的存在, CCD像面实际安装位置相对于系统理想光轴法平面不可避免地会发生倾斜, 倾斜量的存在会导致检测结果不准确。为了研究CCD倾斜角度对衍射对刀精度的影响, 建立了含有CCD倾斜角度的激光衍射光强模型和一级次极大峰值点间距误差计算模型, 并提出了基于一级次极大峰值点间距的角度校正方法。通过实验确定了CCD像面最佳倾斜角度的工艺调整范围, 为有效提高激光衍射对刀的精度提供了依据。

The laser diffraction tool setting is a method of measuring the tool gap by detecting the peak spacing of the laser diffraction fringe. The adjustment of process parameters will affect the measuring precision. And due to the presence of CCD clamping errors, the actual mounting position of the CCD image surface will inevitably be tilted relative to the system optical axis plane. The presence of the tilt amount may cause inaccurate test result. In order to study the effect of CCD tilt angle on the accuracy of diffraction tool setting, the laser diffraction model and the error calculation model with CCD tilt angle were established. And an angle correction method based on the first-order maximum peak spacing was proposed. The optimum adjustment angle of the incident laser was determined by experiment, which provides a basis for improving the precision of laser diffraction.