相位差波前探测与图像重建

相位差技术可以直接利用两幅或多幅图像的强度信息，重构出波前相位信息和目标清晰图像，具有光路简单、成本较低、适用于扩展目标等优点，在望远镜的系统像差检测和目标图像重建方面得到了大量应用。相位差波前探测的关键在于求解非线性代价函数的最优化问题，需要避免陷入局部极值并降低计算时间，才能满足动态变化波前实时探测的需求。同时在重建目标清晰图像时，通常需要做正则化和去噪处理，来提高重建图像的质量。本文主要介绍相位差技术的基本原理，以及近年来的研究进展，并对该技术未来的发展进行了展望。

Phase diversity wavefront sensing and image reconstruction

Phase diversity technology can directly use the intensity information of two or more images to reconstruct the wavefront information and high-resolution image of the target. It has the advantages of simple optical setup, low cost and suitable for extended targets. It has been widely used in system aberration detection and target image reconstruction of telescopes. The key point of phase diversity wavefront sensing is to solve the optimization problem of nonlinear cost function. It needs to avoid falling into local extremum and reduce the calculation time to meet the demand of real-time sensing of dynamic wavefronts. Meanwhile, regularization and denoising are usually needed to improve the quality of reconstructed image. This paper mainly introduces the basic principle of phase diversity technology, as well as the research progresses in recent years, and prospects for future development of this technology.