干涉图空域延拓技术研究

现代干涉测试的核心是用合理的算法处理干涉图而获得所需的面形及参数。用二维FFT方法处理干涉图时，由于FFT算法只能处理数字化的离散数据，且要求数据分布区域必须是矩形区域，因此必须设法将圆形区域干涉图扩展延拓成矩形区域。在研究二维FFT法进行干涉测试基本原理的基础上，提出了一种干涉图空域迭代延拓的原理和方法，利用该方法对一幅实际干涉图进行空域延拓，取得了满意的延拓效果。结果表明，该方法具有较高的处理精度，为波面相位复原奠定了基础。

Interferogram region spreading technology in spatial domain

The kernel of modem interferometry is to obtain necessary surface shape and parameter by processing interferogram with reasonable algorithm. The circular interferogram must be spread into square region when interferogram is disposed by using 2-D FFT arithmetic, which is applied only to numeric disperse data and requires square distributing region.On the basis of the study of the basic principle of interferometry by using 2-D FFT arithmetic, the principle and method of interferogram region spreading is proposed.This technique has been used in region spreading of an actual interferogram with satisfactory resuit. The results indicate that the method has high processing precision and establishes the foundation to phase recovery.