随着制造技术的发展, 机械补偿式变焦镜头的使用也越来越广泛。光学系统变焦的精确性、平滑性和驱动力均衡性主要取决于变焦凸轮, 而变焦凸轮的压力角与凸轮外径、凸轮转角范围以及变倍组的运动规律有关。本文以某款红外连续变焦镜头为例, 不改变凸轮外径和凸轮转角范围, 对变倍组的运动规律进行优化设计, 并通过 ADAMS对优化后的模型进行运动学仿真。仿真结果表明: 该优化方法可以降低变焦凸轮在短焦段和长焦段的压力角, 消除变倍组等速运动时的刚性冲击。

With the development of manufacturing technology, the application of the mechanically compensated zoom lens is becoming increasingly widespread. The use of a cam is the key to ensuring precision, smoothness, and balanced driving force in the optical system. Furthermore, the pressure angle of the cam is influenced by its outer diameter, rotation angle range, and the motion law of the variation group. In this study, an infrared zoom lens is taken as an example, and while maintaining the outer diameter and rotation angle range of the cam as constants, the motion law of the zoom variation group is optimized; the optimized model is introduced into ADAMS for a kinematics simulation. The obtained simulation results show that the optimization method can be used to reduce the pressure angle of the cam in the short- and long-focus sections and eliminate the rigid impact of variation group at the constant velocity.