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ArcticMyst Security by Avery

Scratch on goggles

Joined
Nov 2, 2010
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Hello all.

Question about the lenses on most goggles. If they get scratched, are they still safe? Is the OD factor related to a coating on the lens, or is it usually embedded into the lens material?
 





Sta

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Depends on what kind. If you've got high quality goggles like Eagle Pair, they are probably safe. If you have eBay $5 goggles they may or may not be.
 
Joined
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I have a couple of OEM Laser Systems goggles, and a couple of LaserGlow goggles.

I believe both these companies are reputable?
 
Joined
Mar 27, 2011
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Most tend to be of the same material, so a scratch would not matter. Eagle pair, OEM, are like that. Some goggles I'm sure have a coating instead.

Since you clearly have more than one pair on hand, consider doing a small "test" and seeing how the material reacts in a spot where it would not effect your vision.
 

AngelG

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Nov 6, 2016
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If the diode "burns" (melts) easily the goggles (as black plastic of the same kind), then they absorb well it's wavelength.
I have $3 red goggles which i tested on a 405nm Sony SLD3235FV diode sold on ebay.
I have accidentally pointed the diode into my eyes through the goggles. I saw it like emitting tiny red spot despite it's an UV diode. When I look at reflected from non-fluorescent material beam, I can not see it.
My eyes did not get hurt, but I wasn't running the diode at it's full power. Actually it was 5 promiles PWM at 90mA, because I needed to look at the spot to focus it and it shoud not burn the matte plastic I used to focus at.
5 promiles = 0.005% ( Fpwm=2kHz, Tpwm=2000, Ton = 10 ).
 
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Benm

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I think in general it could be said that with goggles that block out a large part of the spectrum (say pass red, block green and red) the pigment is throughout the lens and a scratch will not reduce the optical blocking much.

In case it blocks a narrow wavelength range (such as blocks 532 but passes 500 and 600 nm) there could be a dielectric coating, and a scratch could remove that entirely. This would probably be visible though.

I've never seen goggles of the latter type, but i believe they do exist, probably for use in specialist applications where good color vision must be maintained (military etc).
 

AngelG

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I agree with the above (there's a typo... they block green and blue]). Moreover I've heard that there exist prototypes of goggles with several selective coatings - for the most common wavelengths of LASERs to protect the military pilots. But I have not heard about their prices.
My $3 glasses block the green and blue light and pass only the red. But this greatly reduces the color vision.
There's another problem: to focus the UV beam, I need to see the spot. So the red ones are inappropriate for this task. I do this at low power with a pair of "retired" yellowish sunglasses which employ polarization filter also. They do not block 100% of the 405nm (neither do my Polaroid sunglasses) so I can work.
 
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