focusing knob meaning in English

调焦钮
调焦旋钮

The resolution of the z axis is dependent on the model of microscope as they all have differing distances per turn of the focus knob
轴分辨率取决于显微镜的型号，因为每种显微镜聚焦钮的移动距离是不同的。
The motor controller and software can also drive an optional z axis or focus motor which can be fitted to the fine focus knob of most of the newer microscopes
电机控制器和软件也可以驱动z轴或聚焦电机，聚焦电机可以安装到最新显微镜的细调旋钮上。