用于三维测量的双路点衍射干涉系统

针对在仅有一个光纤对的单路点衍射三维测量系统中,存在平行于条纹的横向方向上测量精度低的问题,提出了用于三维测量的双路点衍射干涉系统。分析了点衍射波前误差、测量探头结构布局以及三维迭代重构算法对于三维测量精度的影响,在此基础上确定点衍射源结构以及探头结构布局等最优系统参数。实验结果显示,单路点衍射干涉三维测量系统在xy方向的精度分别为亚微米量级和微米量级,而双路点衍射干涉仪系统可在三维方向上同时达到亚微米量级,验证了所提出的双路点衍射干涉系统方案的可行性和准确性。所提出的双路点衍射干涉系统有效的实现高精度三维测量,为无导轨三维位移和尺寸等测量提供了一种可行方法。

Dual path point diffraction interference system forthree dimensional measurement

In the single path point diffraction three dimensional measurement system with only one fiber pair, the measurement accuracy in the lateral direction parallel to the fringle direction is poor. To solve this problem, a dual path point diffraction interference system is proposed to enhance the accurate three dimensional measurement in this study. The influence of point diffraction wavefront error, structural layout of measuring probe and three dimensional iterative reconstruction algorithm on the three dimensional measurement accuracy is analyzed. Based on the analysis, the optimal system parameters (e.g., point diffraction source structure and structural layout of probe) are determined. The experimental results show that the accuracy of the single path point diffraction interference system for three dimensional measurement in the x and y directions are in the order of submicrons and microns, respectively. In comparison, the dual path point diffraction interference system can reach the order of submicrons at three directrions. The feasibility and accuracy of the proposed system are verified. It provides a feasible method for the measurement three dimensional displacement and size without guide rail.