The difference between ordinary optical microscopy and fluorescence microscopy
Optical microscope: It is an optical instrument that uses optical principles to magnify and image small objects that cannot be distinguished by the human eye, in order to extract microstructural information for people.
Fluorescent microscope: Fluorescent microscope uses ultraviolet light as the light source to illuminate the object being tested, causing it to emit fluorescence, and then observe the shape and position of the object under the microscope. Fluorescence microscopy is used to study the absorption, transportation, distribution, and localization of intracellular substances. Some substances in cells, such as chlorophyll, can emit fluorescence after being exposed to ultraviolet radiation; Although some substances themselves cannot emit fluorescence, they can also emit fluorescence after being stained with fluorescent dyes or fluorescent antibodies and irradiated with ultraviolet light. Fluorescence microscopy is one of the tools for qualitative and quantitative research on these substances.
An optical microscope generally consists of a stage, a spotlight illumination system, an objective, an eyepiece, and a focusing mechanism. The spotlight lighting system can obtain different observation methods such as dark points on a bright background (known as bright field lighting) or bright points on a dark background (known as dark field lighting) by changing the lighting method, in order to better discover and observe fine structures in different situations.
Fluorescent microscopy and ordinary microscopy have the following differences:
1. The lighting method is usually a drop type, where the light source is projected onto the sample through the objective lens;
2. The light source is ultraviolet light, with a shorter wavelength and higher resolution than ordinary microscopes;
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 objective lens is used to filter out ultraviolet light to protect the human eye.
Fluorescence microscopy is also a type of optical microscope, with the main difference being the different excitation wavelengths between the two. This determines the differences in structure and usage between fluorescent microscopes and ordinary optical microscopes.
Fluorescence microscopy is a fundamental tool for immunofluorescence cytochemistry. It is composed of main components such as light source, filter plate system, and optical system. It is the use of a certain wavelength of light to excite the specimen and emit fluorescence, which is magnified through an objective and eyepiece system to observe the fluorescence image of the specimen.
