中文摘要：

利用计量光栅的栅距作为基准刻线，对二维精密工作台的运动位移进行测量，提出了一种新的位移测量方法。通过CCD（charge coupled device）获取光栅刻线图像，对图像进行分析处理，计算出栅距与图像像素之间的映射系数，再通过对工作台移动前后光栅图像的对比，采用基于李萨如图的相位差比率算法获取它们的像素位置差，从而计算出工作台的实际运行位移量。

英文摘要：

A new method is presented to measure movement displacement of two-dimensional exact worktable when applying grating as standard reticle. Analyzing and processing the grating reticle image collected by CCD, the mapping coefficient from grid size to pixels can be calculated accurately. Comparing the fore-and-aft two grating images of worktable movement and adopting phase difference ratio arithmetic based on Lissajous figures, their phase difference can be figured out. The displacement can be further calculated by the mapping coefficient.