The electron microscope has three parts, namely, the lens barrel, the vacuum device and the power cabinet. The optical microscope is mainly composed of four parts, namely, objective lens, eyepiece, reflector and condenser.
2. The imaging principle is different.
An electron microscope uses an electron beam to penetrate a sample, and then magnifies the image by a lens. The optical microscope mainly uses the magnifying imaging principle of convex lens to magnify the sample.
3. The illumination source is different.
The illumination source used by the electron microscope is the electron flow emitted by the electron gun; The illumination source of the optical microscope is visible light (sunlight or light). Since the wavelength of the electron flow is much shorter than the wavelength of the light wave, the magnification and resolution of the electron microscope are significantly higher than that of the light microscope.
4. The lenses are different.
The objective lens for magnifying in the electron microscope is an electromagnetic lens (a ring-shaped electromagnetic coil that can generate a magnetic field at the central part); The objective lens of an optical microscope is an optical lens made of glass. There are three groups of electromagnetic lenses in the electron microscope, which are equivalent to the condenser lens, objective lens and eyepiece lens in the optical lens.
5. Different uses
Because of its high resolution, the electron microscope can be used to observe the fine material structure that can not be distinguished by the ordinary microscope, and can also be used to help analyze the material composition. The optical microscope is mainly used for the observation of microscopic materials in biology and medicine, and as an experimental tool for students in teaching.
