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KE5FX:

--- Quote from: jogri on November 02, 2020, 01:17:41 pm ---That's a OD rating of 1.something... Aka: A joke, especially with unknown 100+ mW diodes. You really shouldn't go below 4 or 5.
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How is it a joke?  The data shows that sunglasses have the effect of attenuating the overpowered laser pointer output to levels that international regulatory agencies have deemed acceptable for use without specialized eye protection. Your argument is evidently with those agencies, not with me.

If there's a villain here, it's the shady Chinese vendors who are selling hazardous items for $3 each on eBay.  I can measure the power and spectral output from these lasers and treat them accordingly, but most of their customers can't or won't do that.  I'm not complaining -- hey, cheap lasers are cool! -- but I wouldn't be surprised if governments step in at some point and ruin the fun.


--- Quote ---(Sorry for the rant, but saying that it is safe to look at a laser with anything other than proper laser goggles just doesn't sit well with me)

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I hear you, but the fact is, there are just not a lot of people walking around with eye damage from indirect viewing of laser pointer output without $100 goggles.  Either everyone else is a reckless moron, or you're overly risk-averse.

(Although, to be honest, the more I think about that IR line, the more I'm tempted to swap out the RayBans for my Thor Labs safety glasses that make everything look like it's being viewed through the atmosphere of Venus. They are rated OD 4 at 808 nm, no problem there.)
richard.cs:

--- Quote from: jogri on November 02, 2020, 01:17:41 pm ---But let's tackle the most important reason why both sunglasses and welding goggles are NOT suitable for lasers: LASERS EMIT COHERENT LIGHT
...
That's a OD rating of 1.something... Aka: A joke, especially with unknown 100+ mW diodes. You really shouldn't go below 4 or 5.

--- End quote ---
I am fairly sure the darker arc welding lenses would be "safe". A shade 14 has a visible-band transmission of at most 0.0012%, so min OD 4.9 which is probably OK, but note that it is not nearly so attenuating in infrared (assuming those are percentages in that column it's OD 2.5). The doubling lasers without IR filters are scary.
https://qph.fs.quoracdn.net/main-qimg-63d2b2785a54da76ef6f8efae0ba72e6-c
It's still a crap idea, welding goggles this dark are as good as a blindfold unless you are outdoors in full sunlight.


--- Quote from: jogri on November 02, 2020, 01:17:41 pm ---(Sorry for the rant, but saying that it is safe to look at a laser with anything other than proper laser goggles just doesn't sit well with me)

--- End quote ---
I am inclined to agree.


--- Quote from: KE5FX on November 02, 2020, 01:45:32 pm ---I hear you, but the fact is, there are just not a lot of people walking around with eye damage from indirect viewing of laser pointer output without $100 goggles.  Either everyone else is a reckless moron, or you're overly risk-averse.

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Of course you unlike many people seem to have the ability to measure the OD of your pair of sunglasses. Saying "I've measured these specific sunglasses and I am comfortable with their attenuation" is very different from other people pulling a random pair out of the drawer and trusting them.
sandalcandal:

--- Quote from: jogri on November 02, 2020, 01:17:41 pm ---405 > 400 nm... And 5 nm can make quite the difference for laser goggles as they tend to have rather sharp absorption edges.

But let's tackle the most important reason why both sunglasses and welding goggles are NOT suitable for lasers: LASERS EMIT COHERENT LIGHT

--- End quote ---
The suggestion is the possibility of using broadband protection with safety glasses and welding goggles for general radiation protection so sharp transmittance edges on laser goggles is irrelevant.
The required OD 2.32 at the end of my post is using a laser protection guideline so it is considering coherent light specifically at 405nm CW and the shade 10 is 2.64 OD over visible and 2.80 OD above 365nm. 2.64 OD at x wavelength is 2.64 OD at x wavelength regardless if sharp transmittance materials are used.

I appreciate your concerns though. Laser safety goggles are the go for laser safety. Particularly for anything substantial (Class 3B). I've done research in photonics labs with class 4 lasers as a student.
DrG:
Drill a small hole in a Ping-Pong ball to make a good LED light diffuser.




jogri:

--- Quote from: KE5FX on November 02, 2020, 01:45:32 pm ---How is it a joke?  The data shows that sunglasses have the effect of attenuating the overpowered laser pointer output to levels that international regulatory agencies have deemed acceptable for use without specialized eye protection. Your argument is evidently with those agencies, not with me.

--- End quote ---

Where did you get those facts? Do you mean that it is eye safe because the output is less than 5 mW when it reaches the eye? that number is only valid for IR filtered 532nm green lasers, a 5 mW 405 is a class 3 laser... You can't just assume that just because the output is lower than x mW it has to be safe... The rating heavily depends on the wavelength:




--- Quote from: KE5FX on November 02, 2020, 01:45:32 pm ---I hear you, but the fact is, there are just not a lot of people walking around with eye damage from indirect viewing of laser pointer output without $100 goggles.  Either everyone else is a reckless moron, or you're overly risk-averse.

(Although, to be honest, the more I think about that IR line, the more I'm tempted to swap out the RayBans for my Thor Labs safety glasses that make everything look like it's being viewed through the atmosphere of Venus. They are rated OD 4 at 808 nm, no problem there.)

--- End quote ---

How do you know that? I know a couple of guys with permanent eye damage from a laser, the damage also depends on the wavelength... It can either fry your lens or retina, the guys i know screwed around with 500 mW lasers and got a couple of dark spots in their vision. You only notice that sort of thing when you are staring at a white paper.

And what IR line (your post has no pics)? A 405 nm diode laser shouldn't have a 808 nm line, those kind of diodes are only used in green laser pointers to excite the NdYAG crystal that emit at 1064.
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