自适应光学系统需要信标光来探测波前信息,不同的信标及波前探测模式对系统的带宽和稳定性等性能指标有较大影响.研究系统的性能对合理设计与评价自适应光学系统具有重要意义.根据系统工作时序以及信标光波特性和波前传感器的曝光读出方式,通过机理分析方法建立了自适应光学系统的传递函数模型.推导了系统有效带宽以及相位裕量的计算公式.研究了系统采样频率与控制器参数对系统性能的影响.结果表明,信标与波前探测模式的不同造成系统时间延迟的不同,从而使得系统带宽和稳定性存在差异.

Adaptive optics systems need beacons to detect wave- front information.Different modes of bea-cons and wave- front detecting have a great influence on the performance criterion such as the system band-width and stability.Researching the performance of the system is full of critical meaning to properly design and evaluate a system.Based on the system work flow,the light wave characteristics of beacons,the methods of exposure,read-out of wave-front sensors,and the transfer function models of adaptive systems are built using mechanism analysis methods.The calculation equations of system bandwidth and phase margin are de-rived.The effects of sample frequency and controller parameter on system performance are studied.Results show that different modes of beacons and wave-front detecting can cause different system time delays,which alter the system bandwidth and stability.