Application of optical system simulation software Seelight in adaptive optics
Sun Quan1, Lv Pin2, Ning Yu1, Xi Fengjie1, Liu Wenguang1, Xu Xiaojun1     
1. College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha, Hunan 410073, China;
2. Institute of Software, Chinese Academy of Science, Beijing 100190, China

Overview: Beam propagation and adaptive optics are two of the most important technical problems in the application of modern high energy laser systems. Numerical simulation is an effective method for studying beam atmospheric transmission and adaptive optics correction. Many researches on numerical simulation in this field were carried out in and abroad, most of which are with the simulation programs of the beam atmospheric transmission and adaptive optics system correction. We also developed an optical system simulation software Seelight which can simulate beam generation, atmospheric transmission and adaptive beam control. The software provides an effective simulation tool for the application fields of optical system. The Seelight software is based on the basic principles of wave optics theory and computer simulation, and realizes the construction and design of optical simulation system by means of the graphical interface, which is "what you see is what you get". The software has seven core model libraries, including the source library, the target library, the detector library, the beam propagation library, the control library, the optics device library and the auxiliary library. Each sub-library contains several main modules with independent functions or representative devices. Using the PZT deformation mirror module and the Hartmann wavefront sensor module to build basic adaptive optics simulation systems, which was used to correct the wavefront aberration due to beam propagation through atmosphere. The linear number of the actuators of PZT deformable mirror is 9 and the linear number of the subapertures of Hartmann wavefront sensor is 8. With the adaptive optics system closed-loop control, the beam quality of the far field calculated by CCD camera was improved from 2.9 to 1.4 times of the diffraction limit. A simulation system was built with a 4 km horizontal atmospheric propagation path which included an adaptive optics system. The parameters of the adaptive optics system were exactly the same as those shown in the previous illustration. The correction effect of adaptive optics simulation system was verified under different turbulence intensities which were represented by r0 values from 3 cm to 18 cm @1064 nm wavelength, and it was clear that correction residual errors greatly increased with the increasing of turbulence intensity. The simulation results showed consistent with the trend of the fitting curve according to the theoretical formula in the reference. The Seelight software can be used to simulate various optical systems including adaptive optics system, and the system can be validated and optimized.

Supported by National Natural Science Foundation of China (6150527)