The difference between ordinary optical microscope and fluorescence microscope
Optical microscope: it is an optical instrument that uses optical principles to enlarge and image tiny objects that can't be distinguished by human eyes, so that people can extract the information of fine structure.
Fluorescent microscope: The fluorescent microscope uses ultraviolet light as the light source to irradiate the object to make it fluoresce, and then observe the shape and position of the object under the microscope. Fluorescence microscope is used to study the absorption, transportation, distribution and location of chemical substances in cells. Some substances in cells, such as chlorophyll, can fluoresce after being irradiated by ultraviolet rays; Other substances can not fluoresce by themselves, but they can fluoresce after being dyed with fluorescent dyes or fluorescent antibodies and irradiated by ultraviolet rays. Fluorescence microscope is one of the tools for qualitative and quantitative research on these substances.
Optical microscope generally consists of objective table, spotlight illumination system, objective lens, eyepiece and focusing mechanism. By changing the illumination mode, the spotlight illumination system can obtain different observation modes, such as dark object points on bright background (called bright field illumination) or bright object points on dark background (called dark field illumination), so as to better find and observe fine structures in different situations.
Fluorescence microscope and ordinary microscope have the following differences:
1. The illumination mode is usually episodic, that is, the light source is projected on the sample through the objective lens;
2. The light source is ultraviolet light with short wavelength and higher resolution than ordinary microscope;
3. There are two special filters, the one in front of the light source is used to filter out visible light, and the one between the eyepiece and the objective lens is used to filter out ultraviolet light to protect human eyes.
Fluorescence microscope is also a kind of optical microscope, the main difference is that their excitation wavelengths are different. This determines the difference between fluorescence microscope and ordinary optical microscope in structure and usage.
Fluorescence microscope is the basic tool of immunofluorescence cytochemistry. It is composed of light source, filter plate system and optical system. It uses light with a certain wavelength to excite the specimen to emit fluorescence, and magnifies it through the objective lens and eyepiece system to observe the fluorescence image of the specimen.
