基于变形镜面形的多帧相位反演算法研究

Multi-Frame Algorithm with Deformable Mirror

为了准确利用远场得到近场相位分布,提出了多帧相位反演算法。这是一种利用多个远场以实现传统Gerchberg-Saxton(G-s)算法的相位反演方法,其中的新远场是通过叠加已知像差到待测像差后产生的。在此算法的基础上,提出以变形镜面形来实现反演的方法,并通过数值仿真和实验验证了这种基于变形镜面形的多帧G-S相位反演方法的可行性。仿真结果同时还表明,采用4个变形镜面形产生相应的远场,平均仅需50次的迭代便可反演出不同D/r0数值的大气像差,这些反演的像差与其对应待测像差之间的差别的均方根值平均小于0.005λ。

In order to obtain the near-field phase distribution by using the far field intensity information, a multiframe algorithm is proposed. It is a phase-retrieval algorithm which carries out the original Gerchberg-Saxton （G-S） algorithm by using more than one far field, and the new far fields are generated by adding prescient aberrations to the unknown phase. A novel method to achieve the multi-frame G-S algorithm by using the deformable mirror （DM） is proposed, and its feasibility is certified by numerical simulations and experiments. The simulated results further imply that the multi-frame G-S algorithm is capable of recovering the atomspheric aberrations within 50 iteration loops, on condition that 4 DM surfaces are utilized to build the new far fields, and the root mean square average of residual errors between recovered phases and true phases is less than 0. 005 2, with λ as the light wavelength.