Laser Lithopane etching

Hey guys! Is anyone doing laser lithopanes? I do them with a 1/16" ball nose on my cnc, but it can take 20 hours to do a larger engraving at high-res. I 3d print them as well, and those are beautiful, but I was just wondering if laser could be a 3rd option. I see photos online, but I’m not sure how you prep it.

Thanks!