Vacuum coating of optical substrates

摘要

Method is for coating pref. plastic substrates with a transparent protective layer having a refractive index close to the substrate and one or more optical layers, produced in at least two separates stages, both under vacuum. In the first protective layer, consisting of a cpd of silicon and oxygen or nitrogen. and e.g. between 1 and 5 mu m thick, is deposited in a PCVD-process. The optical layer is deposited in a subsequent stage. A proportion of substrates from the first stage is passed to the second stage and furthermore, the relative speeds in both stages are so arranged that despite different coating times a continuous production is achieved. Also claimed is the equipment required for the first stage.