Abstract

Industrial laser applications often require beam shapes other than the usual bell shaped profile generated directly by conventional lasers. An example is surface treatment processes such as cladding or annealing which benefit from a uniform flat top profile. Traditionally, a multi-faceted beam homogeniser mirror is used to transform the output of a good-beam-quality laser, but this is a relatively expensive component and the spatial coherence of the initial beam produces significant speckle or fringe patterns.

© 1998 IEEE