According to the filter media, it is divided into:
1. Air filter
To make the polluted air clean to the state required for production and life, that is, to make the air reach a certain degree of cleanliness.
2. Liquid filter
To clean the contaminated liquid to the state required for production and life, that is, to make the liquid reach a certain degree of cleanliness.
3. Network filter
Block spam through settings so that the information that appears on your computer screen meets the requirements as much as possible. The principle of absorption separates light of different colors
4. Light filter
Absorb some unwanted light.