基于Fourier变换的快速高分辨波前重构方法
High resolution wave-front reconstruction based on Fourier transform
-
摘要: 为实现快速高分辨的哈特曼波前测量,研究了基于Fourier变换的波前重构方法。在软件设计和代码实施基础上进行了时间性能统计分析,采用模拟数据和实际斜率数据进行波前重构,并将重构结果与VMM方法获得的结果进行了比较,分析其误差产生的原因及噪声的统计特性与误差空间分布的关系。仿真和实验结果表明,FTR方法具有从斜率数据准确重构出波前的能力;相对VMM方法FTR拥有更优的时间性能;基于相同的斜率FTR方法重构出波前与VMM方法的差别主要分布在孔径的边缘,在附加在斜率测量上的噪声具有零平均的性质时,最有可能获得一致的波前。Abstract: VMM(vector-matrix-multiply) method was widely used for wave-front reconstruction in Shack-Hartmann wave-front sensor. Taking advantage of great number of calculations, VMM can give accurate enough result for most of cases, but it can not work properly in scenes which have strict requirement of frequency in time or special domain. In this paper, wave-front is intended to be reconstructed by FTR(Fourier transform reconstruction) method. A common software routine was designed and implemented based on Shack-Hartmann sensor model and FTR algorithms. With the help of these codes, the time analysis of FTR was obtained by software tests. Two kinds of data set were used for the study of accuracy performance, one was ideal slopes derived for known wave-front, the other was slopes corrupted by random noise from actual experiment. Then wave-fronts reconstructed by VMM and FTR were compared and analyzed. Results demonstrate that FTR algorithm has the capability to yield unbiased reconstructions, and shares better time performance than VMM method. Due to extra steps to maintain periodical property of slope data, the wave-front difference between FTR and VMM appears more apparently in edge area. The study and analysis make the limited factors clear, and will guide the implement of FTR in Shack-Hartmann wave-front sensor and supply clues for the improvement in future works.
-
Key words:
- FTR method /
- wave-front reconstruction /
- Hartmann wave-front sensor /
- error analysis
点击查看大图
计量
- 文章访问数: 1327
- HTML全文浏览量: 209
- PDF下载量: 300
- 被引次数: 0