How much do you know about microscope eyepieces
1. Structure of the eyepiece
Usually the eyepiece is composed of upper and lower sets of lenses, the upper lens is called the eye lens, and the lower lens is called the converging lens or field lens. There is a diaphragm between the upper and lower lenses or under the field mirror (its size determines the size of the field of view), because the specimen is just imaged on the diaphragm surface, a small piece of hair can be glued on this diaphragm as a pointer to indicate target of a certain characteristic. An eyepiece micrometer can also be placed on it to measure the size of the observed specimen.
The shorter the length of the eyepiece, the greater the magnification (because the magnification of the eyepiece is inversely proportional to the focal length of the eyepiece).
2. The role of the eyepiece
It is to further magnify the clearly resolved real image that has been magnified by the objective lens to the extent that the human eye can easily distinguish it clearly. The magnification of commonly used eyepieces is 5-16 times.
3. Relationship between eyepiece and objective lens
The fine structure that has been clearly resolved by the objective lens, if it is not re-magnified by the eyepiece, and cannot reach the size that the human eye can distinguish, then it will not be clear; but the fine structure that the objective lens cannot distinguish, although it is re-magnified by the high-power eyepiece, It is still not clear, so the eyepiece can only magnify, and will not improve the resolution of the microscope. Sometimes although the objective lens can distinguish two very close object points, it is still impossible to see clearly because the distance between the images of these two object points is smaller than the resolution distance of the eyes. Therefore, the eyepiece and the objective lens are not only related to each other, but also restrict each other.
