200mW Red Fat Beam Laser Curtain Safety?

[fuzz97]

Hi there,

I'm an artist that creates abstract light installations, I've recently been commissioned to create a piece that I wanted to use lasers for.

I wanted a system of laser point lights that I could control from my console to creat grids,objects and patterns within 3D space.
I've seen these products used in many artworks and concerts before.
After doing a lot of research I came across this lot of 32 fat beam lasers which I could control individually by DMX.

http://www.lanlingtech.com/LN520-6400mW-Red-32-Head-Mobile-Fat-Beam-Laser-Net-p78345017.html

I didn't realize until after they arrived yesterday and I had been programming them for sometime that they 3B laser rating and were as powerful as 200mW per unit.

Obviously these will be going nowhere directly near anyone's eyes, but I'm wanted some advice wether looking at the dots within a white walled gallery space would be in any way dangerous, even for preloaded periods.
Or whether the "fat beam" diffusion makes them a lot safer.

There are many of these fat beam laser rain units that use 200mW or high that are designed to be use above dances floors, such as this.

http://www.jdsound.com.au/products/1020-dune-fat-beam-blue-200mw-blue-laser.aspx

Where I would image direct eye contact would easily be possible.

Thanks

 

[steve001]

No, from direct experience. I've viewed a * multi-watt light blue argon laser at a show up close terminated on a wall, it was very bright and uncomfortable to look at after awhile. The beam was wide. Do a practical demonstration for yourself at home.

* It was 25 watt.

 

[diachi]

No, from direct experience. I've viewed a * multi-watt light blue argon laser at a show up close terminated on a wall, it was very bright and uncomfortable to look at after awhile. The beam was wide. Do a practical demonstration for yourself at home.

* It was 25 watt.

While that's true, local regulations for public laser use must still be followed. In the US that means a variance.

OP, where are you located?

 

[steve001]

While that's true, local regulations for public laser use must still be followed. In the US that means a variance.

OP, where are you located?

Rules and regulations are a separate question.
His question is: Is it safe to look at a 200mW "Fatbeam" laser spot on a white wall?

 

[diachi]

He was not seeking the answer you provided.
His question is: Is it safe to look at a 200mW "Fatbeam" laser spot on a white wall?

So? OP may not have been aware that they must follow rules and regulations that apply to laser displays for their location. The question may never have even crossed their mind.

Whether they asked or not, I pointed them in that direction as a "just in case". It's good to get all the facts before doing something. Say no one bothered to mention and it resulted in the OP getting into legal trouble, what then?

But hey, if you want me just to answer the question exactly and provide NO extra information I can start doing that. :thinking::thinking:

 

[steve001]

So? OP may not have been aware that they must follow rules and regulations that apply to laser displays for their location. The question may never have even crossed their mind.

Whether they asked or not, I pointed them in that direction as a "just in case". It's good to get all the facts before doing something. Say no one bothered to mention and it resulted in the OP getting into legal trouble, what then?

But hey, if you want me just to answer the question exactly and provide NO extra information I can start doing that. :thinking::thinking:

It's still a separate question. They seem to have some awareness of the potential danger and it is good you brought it to their attention.

 

[paul1598419]

The reason the beam on a white wall isn't dangerous is because the beam is scattered and now follows the inverse square rule. For the spot to be dangerous the wall's grain would need to be much less than the wavelength of the laser. At this point the beam may remain collimated and that would be dangerous. This is never going to happen, though. Even glossy white paper is too grainy to cause this problem.

 

[steve001]

The reason the beam on a white wall isn't dangerous is because the beam is scattered and now follows the inverse square rule. For the spot to be dangerous the wall's grain would need to be much less than the wavelength of the laser. At this point the beam may remain collimated and that would be dangerous. This is never going to happen, though. Even glossy white paper is too grainy to cause this problem.

In short you are describing specular reflection.

 

[paul1598419]

Yes, this is the cause of specular reflection. The interference from the scattered waves causes that.

 

[fuzz97]

Thank you everyone for your help and responses.

While that's true, local regulations for public laser use must still be followed. In the US that means a variance.

OP, where are you located?

I am located in Australia.

One thing I have noticed that is conserning for me is the main power supply doesn't have a keystop on it (all 32 lasers run into the power supply unit and are powered by cat6) and the lasers do not have shutters.
I'm not sure what the rules would be for this unit as it's quiet different to a standard event laser, I am meeting with an experienced laser operator tomorrow so they can look at it and give me some feedback.

 

[diachi]

Thank you everyone for your help and responses.




I am located in Australia.

One thing I have noticed that is conserning for me is the main power supply doesn't have a keystop on it (all 32 lasers run into the power supply unit and are powered by cat6) and the lasers do not have shutters.
I'm not sure what the rules would be for this unit as it's quiet different to a standard event laser, I am meeting with an experienced laser operator tomorrow so they can look at it and give me some feedback.

Not sure what the regulations are like in Australia but that wouldn't meet them in the US, I can tell that much.

Let us know what the laser operator you're meeting says.

 

[Benm]

Rules and regulations are a separate question.
His question is: Is it safe to look at a 200mW "Fatbeam" laser spot on a white wall?

Bottom line answer: Yes, as long as the wall has a matte finish and your eyes are at least an arms length away from the spot.

The matte finish is fairly important here though. Your average glossy paper may not be that dangerous, but a very good mirror-finish paintjob might be. A reflection off something like a plain glass window could be too.

As long as the surface is like plain old copy paper or latex paint there would be no danger.

If in any doubt get some smoke or fog in the room so you can clearly see the beam from the laser unit. If you cannot see any beams from the reflection you are probably okay, and you will see reflected beams from things like windows if you set things up properly. In fact, put a sheet of window glass in there and verify you can see the reflected beam off of that