Study On The Preparation Of Optical Antireflection Coatings And Filters For Special Applications

Thin film is prepared by controling a variety of process conditions, such as vacuum, the film thickness monitor and temperature. Film material is deposited on the substrate and then a film state will form. Each process factors have a significant impact on the properties of the final film. Now after a long preparation, techniques have been developed, we have many types now. One of the most common type is the vacuum thermal evaporation method.Broadband antireflection coatings play an important role in the production of optical devices. In order to meet the requirements of the optical element through the visible range such as a telescope, the design and optimization was based on the software Tfcalc. The experiment used ion-assisted deposition, Crystal film thickness controller and an electron beam thermal evaporation deposition method. By continuously improvements and adjustments to the coating process parameters, 400-700 nm broadband antireflection coatings were made. The results showed that: The average reflectivity of visible antireflection coating between 400-700 nm reached 0.36%, better than the requirement of telescope’s optical system such as AR request.Filter is widely used in cosmetics, digital and military fields. The film whose center wavelength is 640 nm was made for the the beauty machine. The film was made by the electron beam evaporation method in the vacuum coating machine. Design and experiment process reasonably and analysis the coating layer performance. Finally the film whose center wavelength was about 636 nm, pass band and stop band are all better than the product standard. The filter was made by an electron beam thermal evaporation coating system and unprovoked ion source. Its change of temperature and transmittance was better than others. It showed better stability of spectral and the ability to control the stress.