How are the focusing knobs of a microscope differentiated?

Focusing knobs on a microscope can be differentiated primarily by size, as they typically serve distinct functions that relate to the degree of movement they provide. The larger focusing knob is generally known as the coarse focus knob, and it allows for significant and quicker adjustments of the stage to bring specimens into general view. Conversely, the smaller knob, known as the fine focus knob, allows for precise tuning of the focal point to achieve a clear image of the specimen after the coarse focus has been established. This size differentiation helps users intuitively understand how to operate the microscope to achieve the desired clarity when observing microscopic samples.

Other distinguishing features such as color coding, shape, or functionality may provide additional differentiation in some models, but the most notable and universally recognized difference lies in the size of the knobs.