Patent ID: 6518540
Filing Date: 2003-02-11
Classification: B23K

Abstract:
A laser apparatus for marking visible surface deformations on the surface of a multi-layered hard disk including an upper carbon layer, at least one intermediate metallic layer, and a lower metallic substrate, comprising:(a) a laser generator for generating an unconditioned output laser beam; (b) a beam conditioner responsive to said output laser beam including (i) a beam expander operative to generate an expanded laser beam and (ii) a beam collimator for collimating said beam; (c) a variable beam attenuator responsive to said expanded collimated beam and operative to generate a collimated conditioned marking beam; (d) a beam sampler in the path of said conditioned marking beam; (e) a beam steerer in the path of said marking beam for directing and focusing said marking beam onto a surface of said multi-layered hard disk and for melting one of said at least one intermediate metallic layers and creating visible markings in said upper carbon layer without removing carbon or metal; and (f) a materials handler for positioning hard disks in the path of said marking beam.