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Eye glasses ruin the beam of 405nm lasers?

Razako

Razako

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I noticed this while playing around outside the other night with my sanwu 405nm. I recently got a new set of glasses, and I notice that they dramatically weaken the visual strength of a 405nm beam and make it look almost 'grayish'. Taking off my glasses the beam goes back to a familiar violet shade, and is much more visible(Although blurry). I assume this is due to some kind of UV filtering on the glasses which also blocks out 'near uv' wavelengths?
 
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Might be because sunlight contains a lot of UV, so this is protection for common consumer.
 
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UV coating on the glasses? A lot of glasses have that now to help protect our eyes from the harmful rays at that wavelength.
 
Razako said:
I noticed this while playing around outside the other night with my sanwu 405nm. I recently got a new set of glasses, and I notice that they dramatically weaken the visual strength of a 405nm beam and make it look almost 'grayish'. Taking off my glasses the beam goes back to a familiar violet shade, and is much more visible(Although blurry). I assume this is due to some kind of UV filtering on the glasses which also blocks out 'near uv' wavelengths?
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Curious experiment; I know I have uv on my glasses, never tried to look at a 405 beam without them. Have to give it a try tonight. Thanks for the heads-up. :)
 
Yeah, UV is the main cause of cataracts. If you spend a lot of time in the sunlight and live long enough you'll be getting them eventually.
 
Do you know what kind of coating your glasses have? Material? I've noticed this with some of my glasses that were coated for glare.
 
BobMc said:
Curious experiment; I know I have uv on my glasses, never tried to look at a 405 beam without them. Have to give it a try tonight. Thanks for the heads-up. :)
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I was thinking the same thing, I've never really tried to see if there is any improvement without my glasses, it'll be interesting, I may be seeing 405nm in a whole new way!

paul1598419 said:
Yeah, UV is the main cause of cataracts. If you spend a lot of time in the sunlight and live long enough you'll be getting them eventually.
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Yep, been there, did that, and unfortunately have them!
 
I'd say it's a realitic option that glasses would dampen 405 nm light to various degrees.

I think even my contact lenses start to filter around there, though it's not that easy to compare as with glasses - the only viable way to switch between them is to wear only one contact lens, but my eyes have different correction factors so that would not be fair either.

I'm not sure if this UV filtering effect of contact lenses is intentional or just a result of the material used to make them, but it's certainly there for the ones i use. I guess it's a good thing in any case as it negates the need for sunglasses.
 
Cool stuff to know. Interested in seeing what results some other people notice.
 
this is normal for any protection glasses, u dont see the beam only the dot, means your eyes are protected.
 
mortuus said:
this is normal for any protection glasses, u dont see the beam only the dot, means your eyes are protected.
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If you're replying to Razako it looks like he's talking about regular eye glasses, not any sort of safety glasses.
 
I have polycarbonate lenses with no coatings and I notice the same thing. A black light tube also looks dramatically dimmer through my glasses.
 
WizardG said:
I have polycarbonate lenses with no coatings and I notice the same thing. A black light tube also looks dramatically dimmer through my glasses.
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I've noticed that with black lights too actually, although not with 405nm as far as I can remember.

Transition lenses will darken under a black light or 405nm light.
 
Razako said:
I noticed this while playing around outside the other night with my sanwu 405nm. I recently got a new set of glasses, and I notice that they dramatically weaken the visual strength of a 405nm beam and make it look almost 'grayish'. Taking off my glasses the beam goes back to a familiar violet shade, and is much more visible(Although blurry). I assume this is due to some kind of UV filtering on the glasses which also blocks out 'near uv' wavelengths?
Click to expand...
Are you talking about mostly "clear" reading type glasses ?
 
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