achromatic phase retarders 基本例句 消色差延迟器 The best material of developing Parallel piece light phase retarder,and the emphasis of this paper is to introduce the piece archromatic retard disigned on the base of that.研制平行片状光相位延迟器最好的材料是云母和单晶石英，以此为基础设计成片状消色差延迟器。