Laser protection lenses are wearing parts, which are used to protect the environment in the laser head cavity from external dust pollution, and are mostly used in laser cutting, welding, marking, cleaning, 3D printing, photovoltaic cells, lithium-ion new energy and other fields. The protective sheets on the market range from a few yuan to several thousand yuan. How to choose fiber laser protective lenses is the basic common sense that many novice buyers need to make up for.