It's not only unsafe but possibly criminally negligent to operate this as is shown on that page.
Casually tossing around phrases like "criminally negligent" spoils all the fun of hacking. Seriously. You are strongly overreacting. Haven't you ever been to a laser show? All that's shown on the linked Hackaday article is a DIY laser projector projecting some cool designs. I don't recall seeing any pictures of people pointing lasers at other peoples' eyes.
Further, it looks like this was all done inside of a research lab by someone who knows what they are doing.
> It's not only unsafe but possibly criminally negligent to operate this as is shown on that page.
we don't have any laws about amateur usage of green lasers in poland, so if you don't hurt anybody you're fine.
last year we had some incidents with people pointing at planes though, but here's not the case.
Certainly if you operated such around random spectators, you'd want to be sure the beam cannot be aimed or reflected at them, but there are certainly ways you could ensure that is so.
The builder on his own, he can do whatever he wants...
According to author, it costed him about 1000 zł - it's about 300 USD. Laser diodes are taken from DVD burners and Blu-ray readers, he also used current stabilizers taken from HP printer, but the most expensive parts, being half the cost, were galvos, used for moving the ray.
He said that it's certainly unsafe, and not only because of potential eye damage -- combined static ray is capable of burning through the cardboard and creating skin burns.
Getting it exported from his country and imported to yours might involve some expensive fun-and-games though, and I'd be inclined to offer more for his time then the $300 above the parts cost, and you need to account for the fact that a lot of his parts were scavenged (if he'd had to more of the parts new it could significantly raise the cost).
Original Polish thread: http://www.elektroda.pl/rtvforum/topic1676990.html