engleski

The determination of thin film's refractive index profile by use of reverse design

All available commercial thin film design software use the model of homogeneous layers for doing the calculations. On the other hand, the real layers do rarely fully correspond to the theoretical model and very often their refractive indices are more or less non-homogeneous. This is especially noticeable at the substrate-film boundary where we usually have a refractive index gradient due the onset of the film's nucleation and growth. We used the reverse design to determine the refractive index profile for the monolayers made on the glass. Generally the problem of reverse design is a complicated one, but here the boundary conditions were pretty well known, and our extensive multilayer design experience was a deciding factor. Several popular optical materials like Al2O3, ZrO2 and HfO2 have been studied. Results have shown that the exact knowledge of the refractive index profile of the first layer on the glass is crucial for production of high quality antireflective coatings.

thin films; optics; design

nije evidentirano