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FrozenGate by Avery

Red Laser Enhancements

randomlugia

randomlugia

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Hey, I'm thinking about making a Bluray laser. And I have these red laser enhancement glasses. They're really strong, and completely block green laser light. Could I use these with bluray? All the laser glasses I've seen said "for green and blue lasers". So if they work, that would really help me out. :) Thanks.
 





randomlugia said:
Anyone...?
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I don't know about others on the list, but I have no idea what "red laser enhancement glasses" are. What wavelengths are they rated for? Does that rating cover, at least, 400-415nm?

Peace,
dave
 
Laser enhancement goggles enhance red laser light. They can be used to block out green.
 
Spyderz20x6 said:
Laser enhancement goggles enhance red laser light. [highlight]They can be used to block out green.[/highlight]
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I would NOT trust my eyes to these things. "Green" is a long way from "violet." Unless you know what wavelengths they are made to block AND how much they block, you are gambling your eyesight for a few dollars.

Peace,
dave
 
daguin said:
[quote author=Spyderz20x6 link=1223345149/0#3 date=1223437785]Laser enhancement goggles enhance red laser light. [highlight]They can be used to block out green.[/highlight]
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I would NOT trust my eyes to these things.  "Green" is a long way from "violet."  Unless you know what wavelengths they are made to block AND how much they block, you are gambling your eyesight for a few dollars.

Peace,
dave[/quote]
They were actually used in the past by WL as "532nM protective goggles" ::)
 
They're almost too good at blocking green, though how good they are at blocking violet light I don't know. They have a darker red tint, especially compared to the certified ones FrothyChimp is offering. You might want to invest in some of the real goggles if you're that concerned.
 
You get them with the lasers you use to line things up like picture frames. I could try them, and if they don't work I guess I'll just use my laser outside untill I buy good ones. :) Thanks anyway.
 
Please also remember that not letting you see scattered light through the lens is NOT the same as protecting you from an accidental "direct shot". Generally with stuff like that, there is a dye in the glasses that does block/absorb that color of light such that the light coming through is lessened when you see scattered light.

But that dye can only absorb so much light. It is VERY possible that a direct hit from a laser can bleach the dye very quickly, leaving you completely unprotected. Remember that a direct hit is what the goggles are most needed for, to protect you from that permanent damage, and a laser has a much higher power density than just light being scattered that you see normally. A direct hit with a high power density laser can bleach the dye, and it would literally be as if you had nothing on at all.

Laser goggles are certified and tested to insure that they do not bleach (or at least do not so so quickly) even with a direct hit from a laser. I seem to remember that the specifications call for the goggles to block at least the rated amount of light, ie stay above OD ##, for at least 10 seconds before bleaching and allowing the light through. That 10 seconds could be the difference between permanent damage and just a headache. Goggles that are not certified as laser safety goggles can never be guaranteed that they don't bleach and expose your eyes to dangerous levels of light. Really, is the money worth your eyesight? You've already spent money on a laser, what's a little more money for goggles?
 
I'm not arguing with you, and I am definately going to get laser glasses after what you just said, but couldn't you hold the laser on the glasses for 10 seconds to see if it bleaches? And what about blueblock sunglasses?
 
randomlugia said:
I'm not arguing with you, and I am definately going to get laser glasses after what you just said, but couldn't you hold the laser on the glasses for 10 seconds to see if it bleaches? And what about blueblock sunglasses?
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Alright, let's do some math (I trust you're not too averse). And please verify the math for yourself; to me it's like how you have to pack your own parachute when you go sky-diving, since it's your eyes, it's all up to you.

Let's be general and say your glasses are OD2 at the wavelength of your laser. Given this, under normal circumstances, they block 99% and allow through 1% of the light that hits them at that wavelength. This holds true for any glasses under normal, scattered light of relatively low intensity. If you have a 200mW laser, laser goggles that are OD2 will allow through 2mW of light in a direct hit, which is low enough that your blink reflex will save you from permanent damage. All good so far.

Now, you hit your glasses with your 200mW laser. If they are certified laser glasses, 10 seconds of direct exposure will leave your glasses still at OD2, still letting through only 2mW, and you'll still be safe. But if your glasses are not certified for laser protection, the dyes will begin bleaching immediately. I'm not talking making a colorless area and letting through all the light. 5mW is the limit for how much power your blink reflex can save you from. 5mW is 2.5% of 200mw, so the laser would only have to bleach enough dye to let in 1.5% more light in order to result in permanent damage.

Laser goggles won't do this, it will still only let in 1%. But with your non-certified goggles, only 1.5% of the dyes have to bleach to make them unsafe.

Can you test this? With a meter, maybe so, but that meter would definitely cost more than a certified pair of goggles. So can you, with just your bare eyes, tell if the light coming through gets 1.5% brighter over the course of 10 seconds? I sure can't, and I certainly wouldn't bet my eye sight on it. And that 1.5% is all it takes.
 
But wait, you said the extra 1.5% would be dangerous, but you also said that it would take more than 2.5% to cause damage because of the blink reflex. So are you trying to say that if less than 1.5 is bleached, it's safe?
 
Best way to try it, is grab the blu-ray and shine it right into the goggles, Put a piece of paper on the other side, and if nothing, or a really really faint dot gets through, it should be fine. Usually common sense is good enough to point the laser away from your eye if you do accidentally hit it. If you purposely shine it in your eye, then maybe you deserve to go blind :P

Goggles are not there to protect you from a direct, intentional hit from the laser, they are for reflections and BRIEF hits from the laser. If it doesn't let any blu-ray through, or if the amount is VERy little, it should be good enough.

If you can, deffinately get some real goggles (ones that block blue could work, and there are multi-wavelength goggles out there.)

Blu-rays dont emit IR, like green, so that is not a problem.
 
I've heard at least twice that green laser goggles are good for blocking blu-ray as well, but I doubt this is true much.

First of all, blu-ray is not blue. 405nm is blu-ray (violet), which is a lot further from green than blue normally is.
Second of all, my green goggles (which I admit aren't that high-grade or anything) say they only have OD1.5 for 470nm-555nm.

OD1.5 Isn't enough at all, imho you would need at least OD3 at the wavelength of your laser to be protected sufficiently. Unless it actually states the OD level for 405nm or you can find a curve for your glasses somewhere (or test it, preferably with a LPM) I would never assume anything except blu-ray goggles actually block blu-ray. If you want some cheap goggles for blu-ray, check my sig.
 
randomlugia said:
But wait, you said the extra 1.5% would be dangerous, but you also said that it would take more than 2.5% to cause damage because of the blink reflex. So are you trying to say that if less than 1.5 is bleached, it's safe?
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No, that's not what I'm trying to say. If less than 1.5% bleaches, that would be safe IN THIS EXAMPLE, but my point is how will you know. I'm saying you can't tell if it's safe or not, because how are you going to measure if less than 1.5% or more than 1.5% bleaches? Can you look at the dot, with your bare eyes, and tell if it's 4mW or 6mW? Even without any bleaching, how will you know if the dot coming through the glasses is more than 5mW or less than 5mW? I'm just saying there's no way for you to test and see if the goggles are safe or not, so trust the people who DO know how to test them, the people who make and certify them for use with lasers.

Without certified goggles or a laser power meter to test your own goggles, there's no way to know if the glasses will protect you or not. There's just no way to know. Plus, even if you test with your own meter, I trust the equipment of certified goggle testers and manufacturers more than I ever trust a hobbyist meter. A hobbyist meter is just for hobby, it's not designed to be great at what it does and no one's life depends on it. A company making or selling safety goggles DEPENDS on the accuracy of their meter. If they screw up, they lose their business, lose their jobs, and someone loses their eyesight. A trusted company will always be more accurate.

Again, this was just a back of the envelope example of the kind of calculation you can do. The math is all simple, you can do it yourself.
1% already coming through OD2 goggles. 2.5% of a 200mW laser is dangerous. 1% already coming through, plus 1.5% added from breakdown. So the line between safe and not safe is 1.5% wide. I'm just trying to say that the difference between safe and not safe is tiny, extremely small, and too small for you to ever see or trust with just your bare eyes. 1% change is fine, but 2% is not, can you see that tiny difference?

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Things: That's bad advice, surely you know better. Goggles ARE designed to protect you from direct hits, that's the kind of hit that does the most damage, that's the whole point of wearing goggles. Anything that protects you from direct hits will also protect from weak reflections, as far as OD goes at least. A direct hit doesn't have to be intentional. Just read on here, how many times have people been accidentally hit with a fill 100+mW? I've seen multiple accounts on the internet, even with people who are extremely careful all the time.

To me, there's no "If you can" about goggles. If you can afford a laser, then you can afford goggles to protect you from that laser.
 
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