介绍了一种小型大变倍比变焦相机的主要技术参数，以及采用的变焦方法; 详细描述了相机的组成结构，其中变倍和补偿透镜组通过滑架在主体内滑动，其运动轨迹取决于导钉在凸轮曲线槽内的运动状态; 阐述了加工和装调过程中为保证相机设计质量而采取的精度保证措施，凸轮曲线槽与滚子的配合间隙应控制在6~ 9 μm，确保主体的刚度和圆柱度，变倍和补偿滑架在主体内滑动时的返回空回误差＜2″，滑架直径D与滑架长度L之间的比值≥1。经高低温和振动试验后检测结果表明：在50 lp/mm空间频率下，相机光学传递函数＞02，相机外景成像清晰，层次分明。

The main technical parameters and the zoom method for the camera with small size and large zoom ratio are introduced. Each structural part of the camera is described in detail. The zoom and compensating lens group slide in the main body through the slide frame, whose movements are assured by the movement of the guide pin in the cam curve groove. The measures to ensure the quality and the precision taken in the process and assembling of the camera are expatiated. The clearance between cam curve groove and roller is controlled about 6~9 μm, and the stiffness and column of the main body are insured. The return errors are less than 2″ when the zoom and compensation slide frame slide in the main body. The ratio between diameter and length of the slide frame should be no less than 1. The results show that optical transfer function of the camera is more than 02 in the space frequency of 50 lp/mm after high-and-low temperature vibration tests, and the location images of camera are clear.