基于随机并行梯度下降算法的望远镜静态像差校正

为校正大口径量子通信望远镜的静态像差,提高接收信号光的能量集中度,提出了基于随机并行梯度下降(SPGD)算法的静态像差校正方法。该方法不同于经典的自适应光学校正方法,无需波前传感器,可有效降低系统的复杂性。对SPGD算法进行了分析,在此基础上利用64单元变形镜和CCD探测器搭建了校正平台,并将该校正平台应用到青海湖量子通信地面站望远镜系统,对700mm望远镜的静态像差进行了校正,远场光斑直径由校正前的58μm改善为30μm,验证了SPGD算法对望远镜波前畸变校正的可行性。

Wavefront Correction of Telescope Based on Stochastic Parallel Gradient Descent Algorithm

Aiming at correcting static aberrations of telescope for quantum communication and improving the energy concentration of receiving signal light,the method of static aberration correction based on stochastic parallel gradient descent(SPGD) algorithm is proposed.Unlike the conventional adaptive optics systems,the SPGD algorithm does not require the wavefront sensor,and can effectively reduce the complexity of system.An adaptive optics aberration correction test-bed is set up with a 64-element deformable mirror(DM) and a CCD detector.The static wavefront aberrations of a 700 mm telescope is compensated,and the far-field diameter is improved to 30 μm from the original value of 58 μm.The feasibility of SPGD algorithm used to correct static wavefront aberrations of telescope is demonstrated.