Which is better - an optical microscope or an electron microscope?
With the rapid development of science and technology, the application of electron microscope in the field of microscopy is very broad prospects, more than the optical microscope has shown its unique superiority. However, because of the application of optical microscope and electron microscope technology and field are different, electron microscope and can not completely replace the optical microscope.
Application in biology, optical microscope resolution is far less than the electronic microscope, because the resolution of the optical microscope by the diffraction limit, so its resolution can not be less than half of the wavelength of the incident light. That is to say, if the incident light of 400nm, then the observation object can not be less than 200nm, but because it can be real-time, dynamic observation, the status in biology is unparalleled, just like in the field of biology is impossible to leave the fluorescence microscope and confocal and other optical microscopes. And electron microscope because of the use of electron beam to scanning imaging, its resolution can easily reach the nanometer level, which is irreplaceable for the application of high-resolution imaging.
In metallographic applications, the magnification of the electron microscope is also far more than the optical microscope, the maximum magnification of the modern electron microscope has been more than 3 million times, while the maximum magnification of the optical microscope is about 2,000 times, so the electron microscope is able to directly observe the atoms of certain heavy metals and crystals in the atom of the neatly arranged array of dots.
Steps for using an optical microscope
1. Hold the arm of the microscope with your right hand and the base of the microscope with your left hand. Place the microscope on the lab bench, slightly to the left. Mount the eyepiece and objective lens.
2 Turn the converter so that the low-magnification objective lens is aligned with the through-hole (the front end of the objective lens should be kept at a distance of 2 cm from the carrier stage).
3,Aim a larger aperture at the through-hole. Gaze into the eyepiece with your left eye (keep your right eye open for later simultaneous drawing). Turn the reflector so that the light is reflected through the through-hole into the barrel. Through the eyepiece, a white bright field of view can be seen.
4,Place the slide specimen to be observed on the carrier table and press it down with a pressure clamp, with the specimen facing the centre of the light-through hole.
5, turn the coarse focusing spiral, so that the barrel of the mirror slowly down until the objective lens close to the slide specimen until (eyes looking at the objective lens, in order to objective lens touch the slide specimen).
6. Look into the eyepiece with the left eye and turn the coarse focusing screw in the opposite direction so that the barrel of the mirror rises slowly until you can see the object clearly. Then turn the fine focusing spiral slightly to see the object image more clearly.
