应用四元数方法对光存储光学系统的建模

光存储中的光学系统是一种非同轴光学系统，其中各个光学元件的设计位置与装配精度是保证系统光线正常传输并获得准确信号的前提。四元数方法是一种可以方便地描述空间光线的传输计算与坐标变换的数学方法。通过将四元数引入到光学头光学系统的建模中，使用四元数法表征非同轴光学系统的传输方式，并给出建立光学元件的设计、安装参数与聚焦光斑、读出光斑之间关系的流程图。据此模型对各个独立的研究对象进行分析的结果，对光存储中光学系统的设计与生产装配工艺的制定有指导意义；同时,以此模型分析物镜的连续运动对光斑和读出信号的影响，对光学头中的可执行机构力矩器的设计有实践作用。

Modeling of optical system for optical storage with method of quaternion

The optical system for OPU(optical pick-up) is a uncoaxial optical system.The design position of optical element and its accurate assembly are critical for the proper operation of the system.Quarternion is a convenient mathematical method to describe the spatial light-beam propagation and dimensional coordinate transfer.Three types of light-beam propagation in the uncoaxial optical system of OPU were characterized with quarternion,and the arithmetic method of the light propagation for the system was established.With the model,the flow chart for describing the relationship between optical component design,assembly parameter,foucsing spot and readout spot is obtained.This model can be used for analyzing optical assembly error,instructing assembly technicians,simulating the focusing of objective lens or tracking the displacment of objective lens.