误差均化的拼接技术

Stitching Technique by Error Averaging

利用相关拼接技术实现光学波面检测 ,可以用较小的测量口径实现较大面积的测量 ,并保持高的测量精度、高的空间分辨率和系统的低成本。获得高精度的子孔径波面分布和有效的拼接方法是这一技术的关键。最简单的两两拼接的方法由于在拼接过程中存在误差积累 ,对全孔径拼接精度有很大的影响。采用误差均化的拼接方法 ,要求所有拼接区中相差值的平方和同时达到最小。从本质上看 ,这是一种并行算法。给出了在平面直角坐标系下误差均化拼接的数学模型和求解方法 ,进行了计算机仿真。

In the measurement of optical wave front, a large scale area can be measured with an interferometer of small aperture by correlative stitching technique, in which high measurement precision, high spatial resolution and low price can be maintained. In this technique, a way to get high precision phase distributions of sub-apertures and effective stitching method are important. Stitching between two sub-apertures is simple, but its accumulation error may reduce stitching precision greatly. The paper presents an error averaging method, which requires that the sum of the squared differences of all common areas should be minimized simultaneously. This method is a parallel one in essence. A math model and a solution in Cartesian coordinates are presented. Their validity has been examined by computer simulation.