Principle of optical coating: The interference of light is widely used in thin film optics. The common method of optical thin film technology is to coat a thin film on the glass substrate by vacuum sputtering, which is generally used to control the reflectivity and transmittance of the substrate to the incident beam to meet different needs.

In order to eliminate the reflection loss on the surface of optical parts and improve the imaging quality, it is necessary to plate one or more transparent dielectric films, which are called antireflection films or antireflection films. With the development of laser technology, there are different requirements for the reflectivity and transmittance of thin films, which promotes the development of multilayer high reflection films and broadband antireflection films. In order to meet the needs of various applications, highly reflective films are used to manufacture polarizing reflective films, dichroic films, luminescent films and interference filters.

Extended data:

Optical thin film is realized in a high vacuum coating room. The conventional coating process needs to increase the temperature of the substrate (usually about 300℃); More advanced technologies, such as ion-assisted deposition (IAD), can be carried out at room temperature. IAD process not only produces films with better physical properties than conventional coating process, but also can be applied to substrates made of plastics. The main vacuum pump system consists of two cryogenic pumps. Control modules for electron beam evaporation, IAD deposition, light control, heater control, vacuum pumping control and automatic process control are all on the front panel of the coating machine.

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