介绍了PW法在连续变焦光学系统初始结构求解过程中的应用。在物像交换原则的基础上对光学系统的各组件进行光焦度分配和间距的选择得到变焦系统的结构形式。通过改变PW值的大小以及正负选择最佳的玻璃组合, 消像差以及计算透镜的形状。利用PW初始结构求解法设计得到了焦距为50 mm~20 mm的中波红外变焦系统, 该系统包括5片透镜以及2个非球面, 结构简单并且满足100%冷阑匹配。最终得到光能透过率高, 成像质量好的连续变焦光学系统, 可以满足实际应用需求。因此, PW初试结构求解法在连续变焦光学系统设计中具有一定的借鉴意义。

The solving for the initial structure of continuous zoom optical system by using PW method was introduced. The structure was obtained by distributing the power and length between them for each element on the base of the exchange principle of object and image. The PW values were changing for choosing best glass, controlling aberration,calculating the shape of glass. Finally an mid-wave infrared zoom system(50 mm~200 mm) was designed according to this method, the system had 5 lenses with 2 aspherics, satisfied 100% cold shield efficiency with simple structure.Moreover, the initial structure was optimized with Zemax.Result shows that the continuous optical system has high image quality and high energy transmission, which can meet the requirements of practical applications. In conclusion, the PW solution has practical meaning for the initial structure of zoom optical system design.