Working principle and structure of metallographic microscope
As we all know, magnifying glass is the simplest optical instrument. It is actually a convergent lens (convex lens), by which an object can be magnified. But the metallographic microscope is not composed of a single lens like a magnifying glass, but of two sets of lenses. The lens close to the observed specimen is called an objective lens, while the lens close to the eye is called an eyepiece. With the help of two magnifications of objective and eyepiece, the object can be magnified to a very high multiple (~ 1000 times).
Structure of metallographic microscope
The most common types of metallographic microscope are desk, vertical and horizontal. Metallographic microscope is usually composed of optical system, lighting system and mechanical system. This paper takes 4xi table metallographic microscope as an example.
Optical system: it is composed of light source, reflector, objective lens, eyepiece and multiple condenser lens groups.
Lighting system: it consists of low-voltage bulb, spotlight, reflector, aperture light bar installed on the base, field light bar installed on the bracket and another spotlight.
Mechanical system of metallographic microscope: it is composed of loading platform (sample platform), objective lens converter (multiple objective lenses are installed), eyepiece cylinder (eyepiece), coarse and fine adjustment handwheel, field light column (adjusting the size of the field of view) and aperture light column (adjusting the light input).