in need of safe laser and help!

[DanG]

The situation you have linked to is EXTREMELY specific and nearly impossible to replicate safely without both a very experienced laser safety officer and extensive government approvals. I never like to suggest that anyone abandon a cool concept but the fact of the matter is that doing this requires much knowledge and is very easy to do incorrectly. I would not recommend projecting laser into audience areas without this expertise under any circumstances.

[nicann]

What do you think by him stating they are safe because special doppler sensors were applied? Any familiar with those?

[DanG]

If you can provide a link to the company perhaps we can tell you better...

I readily admit to being out of my depth here but doppler sensors are usually used for measuring the speed of things with the laser being the medium - not for quantifying the quantity of laser on target for the purposes of establishing MPE. I am also not familiar with any sort of sensor being used in that fashion being approved by FDA for light show (or artistic) purposes. They are also used in some commercial ultra-high power applications but I cannot see that being useful or practical in this case. We just need more information friend.

[nicann]

The artist acknowledges 'Nth Degree Creative for the Laser Fabrication' and Jak Heck.

[WookieBoy]

Hi Nicann.

You said you looked at projection rather than lasers, but the specs for the projector are only 2.5' projection distance?
Does this mean that the projector you looked at only projected an image at 2.5 feet? Or did you mean you only have 2.5 feet between where the projector will be sited and the surface you want to project onto?

There are video projectors that will apparently do 0.22 ratio now. That means you can get a 10' x 7.5' image with less than 2.5' projection distance...
I think the small ones are made by 3M or Optoma
The big beefy ones are made by Barco or Christie (but you're talking many many $1000 to buy these)

Would this be more helpful?

[slicklasers]

Nth Degree is Jeff Silverman... no comment... but Jay Heck is the art director for Laser Fantasy and a very tallented...

[dsli_jon]

TBH I don't see how it can be classified legally safe in the US meaning of the word (ie not needing an audience scanning variation and not needing to be within MPE) unless less than 5mw or being fat beam because whilst there's no denying the beams are at grass level, what happens if a kid lies down and puts their face on the ground?...However, I know little of US laser law so who knows what exemption they may have been able to obtain.

No, I think you're right on the money, WL... sorry, but imho, there's no-way those 'demos' were approved as-is, power-wise - this shot, in-particular -
http://www.corsonart.com/gallery/alb...er_lawn3linesW - looks to me like 'lasershine' from a KTP-sys enclosure at full-bore - no-way this is <5mW, and I would not buy that 'exposure time' was used to make it look-so... Nuh-uh, that's some *power*, there, imo..

..And.. 'doppler sensors'?? I don't see how - even if they were used for 'mass-sensing' to somehow attenuate, they could tell when someone was - like you say - crouching-down and could get an eyeball-full.. And if they're supposed to be used like a 'kill switch' - isn't the whole 'point' for playful-interaction?? I... I..

..So, what power were the 'underbench' shots? Dunno, clearly there was some 'exposure time' (..look at background lighting..) but I'd bet much-more than <5mW.. which, doesn't 'automatically allow you to scan-people with', anyway... I dunno, but.. that.. 'art project'... Mmmm, I'd bet that one was 'snuck under the radar'... which - Sir Nicann - is not a good-example for you to follow, especially if you're gonna be banking patent-work on this all.. those ain't cheap to get, and it would be an awful-shame to have to spend a whole lot more, trying to defend some lawsuit, because, well, 'some other guy did it and said it was ok..' - Bzzt.

..Obviously, I'm sure you / your partner are much 'smarter than that', ..but I use such an exaggerated-example, to make the point... Public-display Laser-fx, like this, in the US are nothing to 'toy' with, if for no-other reason, than liability... It would not seem that you could do much of anything like that sites' example, with lasers, in-such a manner as-to be safe / legal... and visible-enough in *daylight*... Here's a quick example -

This daytime beam-hit photo: ..is *this same* laser: ..Wanna know how much laser-power that 'indoor' beam-shot is? *47.5 Watts* - yet, outdoors, in full-sun, it's scarcely visible...

Yeah, sure - oudoors, you can see even a 5mW green laser pointer spot 'pretty-well' on the ground - even some 'lissajous' patterns will show-up surprizingly-well... but, if you're taking anything like that 'art project', you'd need to scan the beams so 'thin', both for 'coverage' and, as-just *part* of how to do this, safely, I don't honestly see much 'being left' for good-visibility...

Not saying it *cannot* be done, just saying, it's nothing like a 'snap' to do this all... Oh ,and everything Dan (X-Laser) said...

Dos centavitos..
j

[nuphotonix]

you cannot use this display in its current configuration. Have a couple of Patents myself, you should look into provisional patents. You cant patent the laser.

[White-Light]

I wondering now if by doppler they were using something similar to what XBox Live uses that can detect body positions and so maybe there is some kind of safety cut out. However, it all seems a little pie in the sky to me and I'd be worried about replicating it without first getting some first hand experience with the company concerned that enabled you to verify for yourself that the way the effect was achieved was in fact safe and compliant with all US laws.

Jon, that certainly demonstrates the power of the sun! 47.5 Watts and hardly visible in daylight.