Laser Shows in clubs and bars question Noob

[White-Light]

PASS is designed for audience-scanning projectors, and is meant to shut down the projector if the scanners stop moving. But even with PASS, you still need a trained operator present, because you could have a mirror fall off the galvo shaft, yielding a static beam even though the scanner would still be moving.

It's a bit more advanced than that Adam as I'm sure you know. It monitors scanner velocity to check for scans that are too slow, input signal and a whole host of other elements with double redundancy and then applies momentary power reductions to alleviate the problem so the patterns aren't visually affected unless of course its a situation that's totally impossible to protect from with momentary application or if with power still applied in which case it applies total shut off for the duration of the dangerous event. You can also custom adjust the safety horizon. At least that's my understanding.

I also understand its an almost guaranteed way of getting an audience scanning variance in the US as a projector with PASS fitted has never been refused.

That said you are entirely right, it can't guard against a mirror separating unless there's some kind of feedback from the galvos as a result and a physical beam block is the best way of preventing beams entering the audience area.

[norty303]

Lets face it, if a mirror comes off a galvo shaft, the last place the beam is going end up is out the front of the projector.
As far as failures go, thats a pretty safe one.