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Title: Laser projector hazard distance
Post by: Steven Cohen on September 16, 2019, 10:03:20 AM
Hello,

Has anyone used a front laser phosphor projection in a live environment? In other words, using a laser projector projecting images where people are on stage facing the projector's laser output? Panasonic states that the hazard is no different from a lamp based projector.

https://business.panasonic.co.uk/visual-system/sites/default/eu-files/visual-systems/files/technical_downloads/Laser%20Whitepaper.pdf

 
Title: Re: Laser projector hazard distance
Post by: Rick Earl on September 16, 2019, 11:57:05 AM
Hello,

Has anyone used a front laser phosphor projection in a live environment? In other words, using a laser projector projecting images where people are on stage facing the projector's laser output? Panasonic states that the hazard is no different from a lamp based projector.

https://business.panasonic.co.uk/visual-system/sites/default/eu-files/visual-systems/files/technical_downloads/Laser%20Whitepaper.pdf

 

The laser is used to excite the phosphor, which in turn glows very brightly.  At no time is the laser part of the projection path and no coherent "laser light" exits the projector.

We have owned a Canon for a couple of years now, nobody has been injured or gone blind.... yet. :)
Title: Re: Laser projector hazard distance
Post by: Steven Cohen on September 16, 2019, 12:18:37 PM
Thanks for the reply Rick. Just to be clear, this projector will be in the 12K lumen range and be about 40' from the stage.

 I am just trying to figure out what distance the manufacturers are talking about when they refer to risk group 3 hazard distance. Panasonic states "Hazard distance depends on the brightness of the projector and the throw ratio of projection lens.  When staring into the light within the hazard distance, there is a risk to the eyes  from direct radiation. (RG3 area)."

So if I have a 12K lumen projector and a throw ratio of 2, now what do I do to figure out the hazard distance?

 
The laser is used to excite the phosphor, which in turn glows very brightly.  At no time is the laser part of the projection path and no coherent "laser light" exits the projector.

We have owned a Canon for a couple of years now, nobody has been injured or gone blind.... yet. :)
Title: Re: Laser projector hazard distance
Post by: Caleb Dueck on September 16, 2019, 12:26:25 PM
Thanks for the reply Rick. Just to be clear, this projector will be in the 12K lumen range and be about 40' from the stage.

 I am just trying to figure out what distance the manufacturers are talking about when they refer to risk group 3 hazard distance. Panasonic states "Hazard distance depends on the brightness of the projector and the throw ratio of projection lens.  When staring into the light within the hazard distance, there is a risk to the eyes  from direct radiation. (RG3 area)."

So if I have a 12K lumen projector and a throw ratio of 2, now what do I do to figure out the hazard distance?

From my conversations with manufacturers, the issue stems from the term "laser" and the hazards of coherent light. The non-coherent light from a projector isn't an issue because regardless of generation - it's non-coherent. 

Don't look directly into 12k projectors, regardless of source.  😂

If people are looking directly into a 12k projector, regardless of type, that's a design/implementation problem. 
Title: Re: Laser projector hazard distance
Post by: Rick Earl on September 16, 2019, 12:44:23 PM
Thanks for the reply Rick. Just to be clear, this projector will be in the 12K lumen range and be about 40' from the stage.

 I am just trying to figure out what distance the manufacturers are talking about when they refer to risk group 3 hazard distance. Panasonic states "Hazard distance depends on the brightness of the projector and the throw ratio of projection lens.  When staring into the light within the hazard distance, there is a risk to the eyes  from direct radiation. (RG3 area)."

So if I have a 12K lumen projector and a throw ratio of 2, now what do I do to figure out the hazard distance?

This document defines an RG3 hazard. https://www1.eere.energy.gov/buildings/publications/pdfs/ssl/opticalsafety_fact-sheet.pdf (https://www1.eere.energy.gov/buildings/publications/pdfs/ssl/opticalsafety_fact-sheet.pdf)
Using the date from the projector manufacturer and the inverse sqaure law, you should be able to calculate a safe distance. 
The same holds true for old carbon arc follow spots, newer Xenon and arc lamp follow spots,  and many  arc lamp automated fixtures. 
Title: Re: Laser projector hazard distance
Post by: Chris Jensen on October 16, 2019, 10:30:33 PM
Thanks for the reply Rick. Just to be clear, this projector will be in the 12K lumen range and be about 40' from the stage.

 I am just trying to figure out what distance the manufacturers are talking about when they refer to risk group 3 hazard distance. Panasonic states "Hazard distance depends on the brightness of the projector and the throw ratio of projection lens.  When staring into the light within the hazard distance, there is a risk to the eyes  from direct radiation. (RG3 area)."

So if I have a 12K lumen projector and a throw ratio of 2, now what do I do to figure out the hazard distance?

What everyone has said is what I have been told.  Since it is a laser the FDA governs it.  The light output is the same hazard for lamp or laser, no more or less due to the light source.  Electric engine vs gas, imagine if an electric car had to have a warning label to pedestrians telling them they might get shocked?  They are never exposed to the engine.  What the warning should be is stay out of the street.  The silly thing as it has been explained to me from someone at Barco is that the laser triggered warnings here in the US.  Panasonic at first used a cone much like you would put on the dog just to get the first few units to pass until they got it all figured out with the FDA.  The FDA really wasn't interested in understanding the problem as it was not really FDA related.

Barco has a good guide for their units in each manual and as a separate info pack on their web page.  I would suggest using that as it is the same for all units based on the Risk Group they fall into.