利用四元数理论分析了可变延迟波片,并依此由可变延迟波片组合构造了等效可转线性半波片和四分之一波片.提出由可变延迟波片按可转波片控制算法设计偏振控制器,以避免可变延迟波片偏振控制器所需的复位重置过程.仿真结果显示,按此构想得到的四波片控制器,能把任意偏振态转换为固定线偏振输出,其光强波动小于1%,相移范围不超过2π,控制过程不需要附加复位操作,其相移变化平缓.

Variable retardation plates (VRP) were analyzed by quaternion theory and equivalent rotatable quarter-wave plates and rotatable half-wave plates were constructed from sequences of adjustable linear retarders with fixed retardation axes.To avoid reset,a polarization controller (PC) based on adjustable linear retarders using polarization controlling algorithm for rotatable plates was proposed and demonstrated.Simulation results show that the 4-plate polarization controller can transform any varying general input state of polarization (SOP) into an arbitrary linear output state of polarization,and the fluctuation of output light intensity is less than 1% while the rang of retardation is confined into 2π.This transformation is continuous,and reset-free and the phase shifts are smooth.