What Are the Main Differences Between Optical Microscopes and Electron Microscopes?
Optical microscope and electron microscope are two different types of microscopes, with differences in definition, classification, and composition structure.
1. Different definitions
Optical Microscope (OM) is an optical instrument that uses optical principles to magnify and image tiny objects that cannot be distinguished by the human eye, in order to extract information about microstructures.
The application of electron microscopy technology is based on optical microscopy, with a resolution of 0.2 μ m for optical microscopy and 0.2 nm for transmission electron microscopy, which means that transmission electron microscopy magnifies 1000 times on the basis of optical microscopy.
2. Different classifications
There are various classification methods for optical microscopes, which can be divided into three types based on the number of eyepieces used: binocular and monocular microscopes; According to whether the image has a sense of three dimensionality, it can be divided into stereo vision and non stereo vision microscopes; According to the observation object, it can be divided into biological and metallographic microscopes, etc; According to optical principles, it can be divided into polarization, phase contrast, and differential interference contrast microscopes.
Electron microscopes can be divided into transmission electron microscopes, scanning electron microscopes, reflection electron microscopes, and emission electron microscopes according to their structure and purpose.
Observation range of optical microscope
Also known as ultrastructure. Refers to various microstructures within cells that cannot be clearly distinguished under a regular optical microscope. The resolution limit of a regular optical microscope is about 0.2 micrometers. The thickness of the cell membrane, endoplasmic reticulum membrane, and nuclear membrane, as well as the diameter of ribosomes, microbodies, microtubules, and microfilaments, are all less than 0.2 micrometers. Therefore, these cellular structures cannot be observed with a regular optical microscope. To observe various submicroscopic structures in cells, a higher resolution electron microscope is necessary
The fine structures with a diameter less than 0.2 microns that can be seen under an electron microscope are called submicroscopic structures.
