You don’t really need to do that, the laser has great focus for at least a 10mm range. At least the leo69 laser I am using does. The only down side is you can’t really do a half a sphere, you need a little bit of an angle, or a 4th/5th axis. I actually tested the lased on a surface and used the milled half a doughnut from on one of my first videos, works great, no need to over complicate it.
Reply To: Laser engraving on 3D shape, any idea ??