Tinkering the GCMC Guilloche pattern generator to produce an SVG file, then passing it through LightBurn to engrave a DVD worked surprisingly well:
Polycarbonate plastic isn’t something you want to cut in your laser, because it melts and releases The Big Stink™, but vector engraving at high speed produces a clean 0.1 mm line:
The legend around the middle came out well with 2 ms pulses at 0.25 mm spacing:
The black dots in the background were printed on the label side of the DVD.
The vast number of closely spaced points caused the laser’s path planner to pause the machine’s XY motion while it caught up, but without visible damage to the platter. The GCMC program prunes the path to ensure successive points lie more than 0.2 mm apart, but maybe coarser resolution would reduce the planner’s workload without looking any worse.
All in all, the results look (and feel!) much better than the diamond drag engravings: