60mw Green lasers

[mkfs9]

 

60mw Green lasers

Hi just picked up three used 60mw Green lasers. They produce random patterns and are sound activated. Not had much dealing useing lazers so what are basic guide lines, like how long can they be on and where they should be aimed. Thanx .

[timmeh2]

Hi

 

Go here, make sure you read it all.

 

All the best

Timmeh

[Ashley R]

From my own personal use of smaller party type lasers (50mw Green) its reccomended to use them for a max of 4 hours continiously before you start shortening the life of the diode.

 

But definately read any safety regs that you can get your hands on, what I sometimes see with guys who are useing imported 1-5w lasers is downright scary....

[greenalien]

If you point them at the ceiling, no problem.

 

However, if you point them so that they aim into the audience, you must be 100% sure that your show is eye-safe, which is not easy - even a 60mW laser can damage eyesight permanently. First, the laser must comply with the requirements of BS 60825 - part 1, which I'm sure that yours won't, as it is unlikely to have scanfail detection; however, even if it does, you then need to know the power of the laser, and also the pulse length for each figure the laser can display; you then need to do some maths, which is detailed in BS 60825 part 3, to work out the irradiation, for each figure, to find out if you are exceeding the MPE (Maximum Permissable Exposure) limit.

 

The bottom line is that no cheap 'DJ' style lasers comply with the regulations, and therefore must not be used for audience scanning.

[willdoweuk]

Put them in a cupboard and forget about them.

I know people who have been at amateur "gigs" and have had their eyes damaged by cheap imported Chinese lasers.

Not worth it.

[mkfs9]

Put them in a cupboard and forget about them.

I know people who have been at amateur "gigs" and have had their eyes damaged by cheap imported Chinese lasers.

Not worth it.

 

 

I am asking for some advice here beforre I use them. Seems people dont want to give it, put them back in the box is not any help at all. just asking what do you people do. everybody has to start somewhere to gain some knolledge.

[Andrew C]

You have had advice. If you choose not to accept it, that may be between you, the plaintiff and a judge.

 

If you are going to use it, point it above the audience, with a fixed barrier to block the beam if it falls or looses its brain.

[musht]

Good advice to use them as ceiling effects with a beam block to stop any accidental exposure.

 

Laser eye damage is actually quite rare, but everyones seen Day the Earth Stood Still and scratchy eye`s after a night out, must have been the death ray weapon the DJ was using the night before...

 

In depth about lasers: http://www.photonlexicon.com/forums/forum.php

[timmeh2]

Hi

 

There's a well-documented case from Russia where some numpties used an NdYag pulse laser in the wet and blinded a ton of people. There's differing stories, but the essential truth is that laser light was reflected back from raindrops and some temporary structures on the site into the audience.

 

Backscattered radiation is less powerful with CW lasers (of which all proper indoor display lasers are) but you still need to be wary.

 

Just to expand on what Andrew said, I've seen a lot of people correctly set up the size and position of the projection area using their playback software (e.g. Zion or Pangolin) but then not put any mechanical protection on the aperture. If the head crashes or you get a control problem the galvos will stop running and you'll get a single beam of light pointing somewhere, usually into one of the far corners, which is obviously going to be a hazard.

 

Half-decent lasers will monitor the controller and turn off the output if it detects a loss of signal. Bigger ones (mine included) also have a closed-loop feedback system on the galvos and will shut it down if it detects a mirror going beyond a set limit. This is in addition to metal shutters across the aperture.

 

Of course a cheapy sound-activated unit won't have these features but with a bit of common sense you can avoid the pitfalls of operating a laser in this type of environment.

 

All the best

Timmeh