Abstract: Apparatus for coating substrates 31, 31", . . . in a vacuum chamber 2 including a substrate carrier 30 disposed therein and a device 29 for generating a first plasma cloud 28 and, further, including magnets 26, 27 directing the plasma cloud 28 onto the surface of the substrates 31, 31" . . . wherein this device for generating the plasma cloud 28 has an election emitter 11 and a downstream tubular anode 38, the anode has an inlet 10 for the process gas to ignite the plasma and, further, the device is provided with magnets 4, 7 for directing and guiding the plasma through the anode tube 38 into the process chamber 43 and including a device for generating atoms, molecules or clusters of the materials for producing a layer on the substrates 31, 31", . . . , preferably an electron beam evaporator 37 from which the evaporated or sputtered material 33 can be directly applied onto the substrates 31, 31" . . . .

Abstract: The invention relates to a process of providing a scratch-resistant coating for a lens made of an optical material comprising synthetics. In order for the synthetic material, for example a CR 39, to be protected against scratches, a very thin adhesion layer of SiO is applied first, and is subsequently provided with a thick SiO.sub.2 layer. Both layers are deposited in a vacuum chamber which comprises both a thermal vaporizer for vaporizing the coating materials and a plasma source for irradiating the substrate simultaneously with application of the vaporized coating material.