Which is better, an optical microscope or an electron microscope?
With the rapid development of science and technology, the application prospects of electron microscopes in the field of microscopy are very broad, showing its unique advantages over optical microscopes. However, due to the different technologies and fields of application between optical microscopes and electron microscopes, electron microscopes cannot completely replace optical microscopes.
In terms of applications in biology, the resolution of optical microscopes is far inferior to that of electron microscopes, because the resolution of optical microscopes is limited by the diffraction limit, so its resolution cannot be less than half of the wavelength of the incident light. That is to say, if 400nm incident light is used, the observed object cannot be smaller than 200nm. However, due to its real-time and dynamic observation capabilities, its position in biology is unparalleled, and it is impossible to do without optical microscopes such as fluorescence microscopy and confocal microscopy in the field of biology. Due to the use of electron beams for scanning imaging, electron microscopes can easily achieve nanometer level resolution, which is irreplaceable for high-resolution imaging applications.
In terms of application in metallographic analysis, the magnification of electron microscopes far exceeds that of optical microscopes. The maximum magnification of modern electron microscopes has exceeded 3 million times, while the maximum magnification of optical microscopes is about 2000 times. Therefore, electron microscopes can directly observe the atoms of certain heavy metals and the neatly arranged atomic lattice in crystals.
