DIY Laser Goggles

[deluminati]

Was thinking about ordering the stuff to build a few pairs of these. Before you barge in and say "JUST BUY REAL ONES", well, I've already ordered a pair. Just want to experiment with making my own as well. :wave:

I looked through all the Roscolux Theatrical Gel Data Charts, and whipped up this. Thoughts?

 

[HIMNL9]

Consider that they give you "transmission %", and not "OD" data .....

a 10% transmission is just OD1, an 1% transmission is just OD2, where usually for the given wavelenghts, laser safety goggles are rated from OD3 or OD4 and over .....

 

[deluminati]

Consider that they give you "transmission %", and not "OD" data .....

a 10% transmission is just OD1, an 1% transmission is just OD2, where usually for the given wavelenghts, laser safety goggles are rated from OD3 or OD4 and over .....

So OD3 is 0.1%, and OD4 is 0.01%?

 

[HIMNL9]

Right, opposite as photo "stops", that are 1/2, 1/4, 1/8, and so on, OD (optical density) scale is logaritmic, and each OD is the previous one divided by 10.

 

[deluminati]

I went ahead and ordered the IR, UV, Thermal, and Canary filter gels, as well as a couple pairs of welding goggles as the donor units These are the rated goggles I ordered.


If Canary Yellow passes 1% of 445nm, that makes it OD2? So what about two sheets? 1% of 1% would be 0.01%, or OD4? It also has 85% light transmission for yellow/red, so given ambient lighting is good, you should be able to have a pretty decent amount of visibility, even with 4+ layers. Please enlighten me if Im incorrect.

 

[HIMNL9]

Optically yes, but mechanically not ..... they are not made of the right material ..... laser protective goggles are not just rated for an optical density, but also for a resistance for a certain minimum time to a certain power beam (for this reason the specific materials and thickness), where a theatrical gel is usually a fraction of mm, and can also burn in a fraction of second with a high power beam ..... there is no reason for have an OD4 layer, if it can't resist for the time you need for get out from the beam .....

 

[deluminati]

If it's built to go directly over stage lights, it's got to have some degree of heat resistance? Is it counterintuitive to have the colored filter sandwiched between heat shields?

Melting point of electrical tape: 80ºC
Melting point of Roscolux Supergel: 220ºC


Suppose I ordered enough to experiment with.

 

[HIMNL9]

Please do experiments first ..... focusing point of a laser beam can reach MUCH more than 220 C .....

If the gel resist AT LEAST 10 seconds before pass the beam, i think you can use it, but if not, please get real goggles .....

EDIT: anyway, gels don't let you see through too much good, so .....

 

[Bluefan]

I think I read here somewhere that these dyes bleach over time, so I'd avoid trusting my eyes to them.

 

[Bionic-Badger]

If Canary Yellow passes 1% of 445nm, that makes it OD2? So what about two sheets? 1% of 1% would be 0.01%, or OD4? It also has 85% light transmission for yellow/red, so given ambient lighting is good, you should be able to have a pretty decent amount of visibility, even with 4+ layers. Please enlighten me if Im incorrect.

Two sheets would add not multiply, since it's effectively twice the thickness. So 0.5%, not 0.01%. An 85% transmitting sheet would attenuate the input by 15%, and having two would add together to make a total of 30%.

I hope you can get access to a meter for some real testing. The Rosco datasheet isn't going to be exact about its transmission/absorption/etc. because it doesn't need to be, and it's meant for stage lighting, not eye protection. They may also be meant for reducing the output of incandescent bulbs, so they have greater absorption for its spectrum rather than for laser light protection.

 

[deluminati]

Please do experiments first ..... focusing point of a laser beam can reach MUCH more than 220 C .....

If the gel resist AT LEAST 10 seconds before pass the beam, i think you can use it, but if not, please get real goggles .....

EDIT: anyway, gels don't let you see through too much good, so .....

Yeah..Im going to experiment with different combinations of thermal deflection/color filter layers.

Ordered these goggles, btw.
ARG - UV, Blu Ray, Argon, Blue, KTP Green Protection ARG - UV, Blu Ray, Argon, Blue, KTP Green Protection [NR-ARG-EN207] - $78.20