可见光变焦镜头结构优化设计

Optimal structure design of visible zoom lens

针对某变焦光学镜头在宽工作温度(-40～+55℃)下光轴与安装基面的平行度变化容限小(≤0.2 mrad)的特点,利用UG软件的高级仿真模块设计了主镜筒及其支架的安装方式,得到了不同情况下主镜筒的变形分布图。提出了一种光轴变化量的估算方法,间接估算出其光轴变化量,从而优化得到了合理的镜头结构方式。实物镜头的光学传递函数检测及振动试验结果显示,调制传递函数值高于0.2,结构基频为117 Hz。结果表明:系统成像稳定清晰,变焦镜头结构优化设计合理。

The primary tube of a visible zoom lens and its mounting are designed by UG advanced simulation according to the characteristcs of a wide temperature range（-40-＋55 ℃） and little optical axis variation（≤0.2 mrad）,and the deformation patterns in different conditions are gotten by using finite element analysis.An estimation way to get the optical axis variation is proposed,by which the more reasonable structure type is obtained.The results from the lens transfer function test and vibration test show that the Modulation Transfer Function（MTF） is above 0.2 and the fundamental frequency is 117 Hz.The practical image is stable and clear,which indicates that the optimized design of zoom lens is reasonable.