High-efficiency filter (HEPA filter), is an internationally recognized high-efficiency air filtration material, the removal efficiency for 0.3μm or more particles can reach more than 99.97%. HEPA filters can through the interception, inertial collision, diffusion, and static electricity, and other mechanisms, to effectively capture and remove airborne particulate matter, such as dust, pollen, bacteria, viruses, viruses, etc. The use of HEPA filters is of great significance in improving the respiratory environment and preventing diseases. It's widely used in medical, household, industrial and other fields, such as optical electronics, LCD manufacturing, biomedical, precision instruments, beverage and food, PCB printing and other industries, dust-free purification workshop of the air-conditioning end of the air supply. High-efficiency and ultra-high-efficiency filters are used at the end of clean rooms, and can be categorized by their structural forms: high efficiency with partition, high efficiency without partition, ultra-high-efficiency filters and so on.