Was ist ever confirmed that it was in fact a laser? I wanted to make a trivia question out of this ProLok protection, because “lasers for copy protection” sounds just weird enough to potentially be a nonsense answer without context, but I couldn’t confirm that the holes were indeed made with lasers, and not with other means.
Good question. I don't know the answer, but I'm quite certain that it didn't really matter what mechanism was used to mark a diskette. Any damage would be equally strong as a way to detect copying.
I would guess (more or less) identically damaging multiple floppy disks in the same way would be easier with a laser than with something mechanical (e.g. a knife or a drill) (it is fairly easy to control power and duration of a burn), so it might well have been a laser.
On the other hand, disk tracks weren’t exactly tiny at that time in history.
It could be a tiny drop of something corrosive, but with that I’m also still wondering if a laser isn’t simpler, yeah.
I have almost no doubt that it could be a laser, it’s just unfortunate (and maybe a little bit suspicious) that I haven’t found it confirmed anyway. Almost like they wanted it to be a laser (hence the folklore around it), but had to use a less cool method to do it. But of course it might as well just have been a laser, and they for some reason declined to market or even just document it that way, for whatever reason.