In order to solve the blind areaproblem and control the polarization state of the output optical beam of the polarization controller in real-time,a new polarization control algorithm was proposed by using three cascading waveplates. The complexity of the algorithm was reduced and the speed of the polarization control was improved by combining the coarse control( the step-by-step approach algorithm) and the fine control( the proportional-differential algorithm). Through theoretical analysis and experimental ...