An ordinary optical microscope is a precision optical instrument. In the past, simple microscopes only consisted of a few lenses, but the microscopes currently used consist of a set of lenses. Ordinary optical microscopes can usually magnify objects 1500-2000 times. The structure of an ordinary optical microscope can be divided into two parts: one is the mechanical device, and the other is the optical system. Only when these two parts cooperate well can the microscope function.

The principle and structure of a stereo microscope are composed of a common primary objective lens. The two light beams after imaging the object are separated by two sets of intermediate objective lenses, also called zoom lenses, and form a certain angle called the stereoscopic viewing angle, which is generally 12 degrees - -15 degrees, and then imaged through their respective eyepieces. Its magnification change is obtained by changing the distance between the intermediate lens groups. Using a dual-channel optical path, the left and right beams in the binocular tube are not parallel, but have a certain overlap. corners, providing a three-dimensional image for both left and right eyes. It is essentially two single-tube microscopes placed side by side. The optical axes of the two tubes constitute the angle of view formed when people observe an object with binoculars, thereby forming a stereoscopic visual image in a three-dimensional space.