涡旋光在大气湍流中传输时会发生波前畸变, 故需要进行波前校正。相比于传统的带有波前传感器的自适应光学校正系统, 采用随机并行梯度下降算法的无波前传感器的自适应光学校正系统具有硬件实现简单、对光强闪烁等复杂环境的适应性好等优点。仿真结果表明：该系统对单模涡旋光和多模复用涡旋光都可实现波前畸变校正, 能提高模式纯净度。实验结果表明：经校正, 单模涡旋光的光强相关系数可提高至0.85左右, 多模复用涡旋光的光强相关系数可提高至0.72左右, 单模涡旋光波前畸变的校正效果优于多模复用涡旋光。仿真和实验结果均表明, 采用随机并行梯度下降算法的自适应校正技术可有效实现涡旋光波前畸变校正。

The wavefront distortion occurs when vortex light transmits in atmospheric turbulence, so wavefront correction is required. Compared with the traditional adaptive optical system with wavefront sensor, the adaptive optical system of the wavefront sensorless using a stochastic-parallel-gradient-descent (SPGD) algorithm has the advantages of simple realization of hardware and good adaptability of complex environment such as light intensity scintillation. The simulation results show that the system can correct the wavefront distortion and improve the mode purity for single-mode and multimode multiplexed vortex beams. The experimental results show that the intensity correlation coefficient of single mode vortex beam can be increased to around 0.85, the intensity correlation coefficient of multimode multiplexed vortex beam can be increased to around 0.72, and the wavefront distortion correction effect of single mode vortex beam is better than that of multimode multiplexed vortex beam. Both the simulation and experimental results show that the adaptive correction technique using SPGD algorithm can effectively realize the wavefront distortion correction of vortex beam.