根据某探测设备可见光通道光学系统的特点和技术指标要求，详细介绍长焦距大口径连续变焦光学系统结构形式选择、初始结构参数计算及像差平衡的方法，给出运用该方法设计的采用正组机械补偿形式的长焦距大口径连续变焦光学系统的设计结果。对连续变焦光学系统进行了像质检测、实景成像及环境试验考核，其结果表明：该光学系统能满足某探测设备的性能要求。

Based on the features and specifications of the visible optics for a detection system, the selection of optical layouts, the parameter calculation of initial layout and the method of aberration balance for a long focal length, largeaperture optical zoom system are introduced. The optical system design incorporated with mechanical compensation is presented. The image quality test, scene imaging evaluation and environment test for the optical system were carried out. The test result shows that the optical system designed with this method meets the system requirement.