Can optical microscopes observe molecular structures
Optical microscope and electron microscope are two different types of microscopes, with differences in definition, classification, and composition.
1. Different definitions
Optical Microscope (OM) 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.
The application of electron microscopy technology is based on the foundation of optical microscopy. The resolution of optical microscopy is 0.2 μ m, and the resolution of transmission electron microscopy is 0.2 nm, which means that transmission electron microscopy magnifies 1000 times on the basis of optical microscopy.
2. Different classifications
There are multiple 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 stereoscopy, it can be divided into stereo vision and non stereo vision microscopes; According to the observed 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 microscopy.
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.
At present, the molecules are almost indistinct under microscopes, not because the magnification is not sufficient, but because the resolution of optical microscopes cannot reach. The current high-resolution STORM is around 20nm, which means that two points separated by more than 20 nanometers can be clearly seen, while those below 20 nanometers can be seen
Molecules are at least at the nanoscale, and it's hard to say if we use electron microscopy. The magnification of electron microscopy can already reach 10000 times, and the resolution of electron microscopy is at the nanoscale. At the same time, I want to tell you that resolution is very important. If the resolution cannot be achieved, even high magnification is useless.
