Patent ID: 7311939

Claim:
A vacuum coating unit for simultaneously coating a plurality of substrates in a vacuum chamber, comprising: an evaporation crucible defining a vertical axis of symmetry; a substrate holder formed as a dome disposed above said evaporation crucible and having an underside configured to hold a plurality of substrates at radially equal intervals in a ring of substrates about the vertical axis of symmetry of said evaporation crucible and stationary relative to said dome; a rotary drive for rotating said dome about said axis of symmetry, whereby the substrates are moved on circular paths about said axis of symmetry; and a continuous aperture ring formed of one or more screens disposed to partially shadow the substrates relative to said evaporation crucible, said continuous aperture ring being associated, with regard to an evaporation from said evaporation crucible to said substrate holder, with a respective ring of substrates, said aperture ring being a closed circular ring disposed, circumferentially relative to said axis of symmetry, within a cone formed between said evaporator crucible and said dome, and said aperture ring having a circumferentially periodic edge structure at an outer edge or inner edge thereof, said edge structure being a pattern selected from the group consisting of a wave pattern and a sawtooth pattern and having a period substantially smaller than spacing distances between mutually adjacent substrates held on said dome.