The vacuum chamber is made of non-stainless steel, after the factory degassing treatment, with the molecular pump group can reach 5x10-5Pa limit vacuum, which can meet the vacuum environment required for most materials evaporation. The vacuum chamber is opened with a lid, which is easy to take lofting. The chamber is equipped with an adaptive observation window with a baffle for observing the coating process. The baffle can effectively prevent the observation window from being polluted by film material.

The physical process of evaporation coating mainly includes material evaporation, transport of gaseous particles, and deposition on the substrate to form a film. During evaporation, the material must gain enough thermal energy to overcome the intermolecular binding energy, allowing it to transition into gaseous molecules and escape from the surface of the evaporation source. These gaseous particles travel in a straight line to the substrate surface with little to no collisions and condense to nucleate and grow into a solid-phase thin film.