Green Laser for Light Show -- Terrible Idea?

[jtxx000]

I'm considering purchasing a 5mW green laser from DealExtreme for a simple DIY DJ light show; is this safe? I read somewhere that DX lasers are often more powerful than labeled, and I certainly wouldn't want to burn anyone's eye out. Also, do the DX lasers come with IR filters? The page says they don't, but some of the reviews say they do.

 

[pseudolobster]

For light shows, people generally use the most powerful lasers they can find. Since the beam is being pointed at a wall, not into people's eyes, it's a fair bit safer than just playing with a pointer.

DX greens as a rule can be assumed NOT to have IR filters... though their tested output includes the IR.
That means, your 5mW green might only be 2mW of green, and 3mW of IR. Either way, 5mW isn't enough to cause any damage unless you're staring directly into the beam for more than a second.

I'm no expert, but I'd say you'd need well over 100mW to have any problems from looking at the dot on a wall. 5mW is certainly not going to be a problem.

 

[jtxx000]

I was thinking more along the lines of a slow sweeping laser beam rather than pattern projected onto a wall. Either way, I suppose you would blink in less than a second, so it shouldn't be much of a problem then. Am I correct in assuming that the IR output would be too small to cause any problems?

 

[Razako]

You will be fine with a dx 5mw green unless you get one of the freaky ones that put out 20+mw of green and 10+mw of IR. Generally if the laser can burn holes through thin plastic it isn't eyesafe.

 

[MarioMaster]

i've found most DX5 lasers to be way more than 5mW, I just sold one that hit into the mid 20's and my art teacher's DX5 is way brighter than my core which has a tested output of almost exactly 5mW - plus they leak almost no IR (unless you are unlucky and get one without), I tested the dx5 that was outputting 20+mW and not even 1mW of IR was being emitted

 

[BlueFusion]

slow sweeping???
If that's what you're planning - no laser is safe.
10-20k systems are ok for crowd scanning with even watts, as it's only on your eye for 1 20,000th of a second.