Well, I'm a Croat, so that's both mad and knowing what I'm doing ...
Seriously though, a diffuse reflection of a wall at more than 2 meters is NOT going to set your eyebrows on fire (despite the impression one might get after reading a lot of posts here about Class IV lasers).
You just gotta be real careful not to point it at something shiny, but then again, shiny objects are usually on a table or something like that, and you've got no reason to point a high power laser at your table randomly.
And that's the whole point, being smart when using lasers, not just protecting your eyes and not giving a f**k.
What's the point of having all the lasers, if you never actually see them?
Goggles are preventing you from an accident. Unless a posibility arises that my wall suddenly transforms into a mirror out of protest to all the lasers being shone at it, I will not be immediately putting my goggles on every time I want to play with my laser for like 2 seconds before going on about my business I was doing in the first place.
And to be honest, mirrors can be a lot safer than diffusive surfaces, you know where the beams gonna end up, and very little diffused brightness.
But this isn't why I started the thread. I am just trying to get across the point that lasers CAN do permanent damage, but that it isn't likely the you will notice that damage right away; it is cumulative, and irreversible. That isn't to say that you must wear glasses ALL the time, but that it is really hard to know when until you have done enough damage to be able to "look" back and say "Sh@*! I should have been a bit more careful!" Pun is fully intended. So maybe $2 glasses aren't such a bad idea.
magmabeam: Please do not mince words with me, you know the message I am trying to get across, don't you? If not, let me know, I am happy to clarify as much as it takes. I am not trying to start 'sh@*' as they say.
bennet326: I personally think that a person should wear goggles anytime that a 'dot' leaves spots in one's vision. This was not common sense to me, but maybe I have none.
+1 for good thread and great sense- good replies too.
I have attended two huge lasermeets(SELEM IV & V) with mega watts of photons going on all over the place and rarely saw anyone using glasses as long as they were in the 'safe' zones and knew exactly what they were doing. However when aligning beams , repairing big gas lasers etc they were there in place, always.
The overreaction you see here is in response to so many posts from the slow-wittted interested soley in burning balloons and popping matches to impress thier friends and reinforce the notions many have that lasers are only good for putting your other eye out.
They make getting proper eyeware a last priority and have a cavalier attitude about it. One referrd to the laser he was wanting as a death ray..
I personally advise that showing how cool other things are--such as lumia-tunnel efx-spiro- and liquid sky is the only thing we should be showing off. Dont expect someone with a preconceived bad attitude towards our 'hobby' to change thier point of view by seeing matches ignite.
When the first of the new 445 nm diodes were found one guy wrote that he spent quite a while measuring the spots on a white wall at variing distances in order to get a good idea of its divergance.
He wrote, IIRC, that he got a bit of a head/eye ache from it and for a few days later lost much of his green vision- his lawn looked brown and he had a hard time seeing the green traffic lights. It did pass but I bet he was worried until it did.
When I have guests at my private laser/music parties I show all there the safe zones- and hang glasses on thier necks with strict instructions to wear them while moving about and not taking them off until there are for sure in a safe zone.
To have nearly a dozen pair has cost me some money but what price can one put on our vision. Most are cheap 'guest goggles'. My personal ones--not so cheap.
thanks for your thoughts on all this. And great posts by Eud, Bennett, and others too.
i agree about your showing off other things, people tend to get a wow out of lighting a match, but when i show them the spiro they go " hey let-me see that, how does it work man that's awesome" and by then they have forgotten the popped balloon
Its not rocket science, own the right glasses and wear them when you need to.
I rarely use glasses because im always in the open when i use my laser, kinda hard to reflect off of something when im pointing down from flat roofs .
I dont use my laser inside, does nothing for me, i get to work at night or early mornings whenever i want to, so im on empty commercial / industrial sites by myself alot in the a.m.
Own glasses or leave, maybe
Use glasses all the time or leave, just stupid
Well, that photo I posted earlier in this thread, the Before photo, that's the kind. Also a lot of similar stuff with the 405nm. But I'd bet that the majority of the damage done to my vision was the 445nm (like the photo) and playing around with the first commonly available burning lasers, the 650-660nm's. It really is kind of fascinating burning stuff, but that isn't all of the attraction. And I am not leaving out the 532nm's, since so many do not have an IR filter; who knows how much damage is being done.
Really, anything that leaves spots in your vision is BAD! (and many that don't)
Yeah, I know my answer is pretty vague. I just can't be more specific. That's the point of my OP. I just don't know exactly when or with what laser under what circumstances I did the damage. I just know I did. I know it wasn't with the 808nm diode laser arrays, because I had GOOD goggles on the entire time. The threat was SO obvious, even I paid heed to the safety issues from the get-go.
how many mw where your red an green lasers.
i have been reading alot about safty. and i see how serious it is.
i just recieved my first "real" laser oke maybey the second. my 5mw green one migh be overspec. its way brighter then my 200mw red which i just recieved.
i don't have any glasses yet i might buy those +-20 dollar glasses @ lazerer.
or is their a real cheap alternative.
so i have tested my laserpointer and pointed it on my wall and carpet.
the wall is white an 10 meters away. the carpet is blue. an the rest outside @ night
and it was for very short periods of time. ( i assmume very reasonable this would not have done any damage. but i know you have to be real carefull ITS NOT A TOY)
i already found i am not a burner i lit one match oehhhh to see if it works but it doesnt burst my bubble, i rather like pointing it up in the sky or point at very distand objects. i love how far it travels.
i also got a love for bright flashlights because they throw far. but nothing beats a laser
i think i will love the 50mw green one which i will recieve soon the most. its not about the power for me but about a nice beam.
and 50mw gonne be plenty.
yes yes and plenty to kill my eyes. i know. and its soo easy just make that one mistake.
so i am uber causious and dont even focus the beam too much so its a big dot on my wall
but i really wounder about my green laser nowis 5mw really that bright my 200 mw doesnt compare at all.
is my cheap green dx overspec? i start thinking it is. ( video to compare http://www.youtube.com/watch?v=h_td1nxiyfM)
and i hope you dont ge me wrong i understand you guys totaly on how mandatory glasses are.
I very seldom use my laser safety glasses, I like to see the beam. My vision is already bad from years of welding and I don't think my lasers have made my vision any worse but I could be wrong
I had a crack in my welding lens that I couldn't see a few years back when I was welding Titanium, didn't even realize the crack was there until my eyes started hurting later that night and had to go to the emergency room to get some eye drops. I had to look hard to find the crack in the lens, so I do know what it is like to get eye damage and not realize that it is happening. Now I wear glasses and the more welding I do and the older I get the worse my eyes get.
Lights fascinate me and keep me hooked on lasers, the safety glasses ruin the light that I like to see. I figure as long as I am careful I will be fine.(might be wrong)
fixitiwill I get your point, I do have some damage in my left eye and I was wearing safety glasses and a face shield when I got a metal sliver in my eye from a high speed rotary file. The sliver was about 3/8" long and went in pretty deep, I had to have surgery to have it removed. Eye injuries SUCK!
You will have to forgive me if I have rambled a bit, I haven't had very much sleep and my brain is a little foggy.:beer:
SKeijmel, it is good to see you have an interest in safety. I don't have any advice to give on inexpensive safety glasses for green lasers, not yet anyway... I am always on the lookout for them from unexpected sources, but have so far been unsuccessful finding them (this may soon change, I just found another possible 'source')
As for the power of the lasers I have owned during the years I believe the damage was done, I'd really only like to say that it was all over the spectrum... err maybe that isn't the right word... say Wattage range (as well as frequency spectrum). But I'd like to answer your question as asked, so here is what I remember the laser's power was supposed to be as far as the ones that I owned.
I had a 200-250mW green for about 1 - 1.5 years.
Several 150-250mW reds for at least that time.
2 100+mW violet for about 4-6 mos.
2 50+mW green for 2-3 years
Several 5+mW greens for 4+years
A ~20k-40k+mW infrared for about 2 mos (ALWAYS WORE GOGGLES)
Several 600mW-1.5kmW blues throughout the last 2 years
Please remember, I don't own a meter, so I can't verify powers.
More importantly - ambient lighting conditions, target surface reflective properties and some other factors such as viewing period, spot size, and distance have more to do with the damage potential of a laser than do the power. Also, don't forget, that 1Watt is 1Watt whatever the wavelength, the only difference is that with colors that 'seem' bright, our pupils dilate (get smaller) therefore protect us better. 1Watt of red under average lighting at a distance of 1 meter on a brick will be more damaging than will 1Watt of green under average lighting at a distance of 1 meter on that same brick...
because our eye's built-in protective measures notice that there is a danger MORE when it is green than red (or blue)! (and therefore dilate our pupils)
It is not easy to set simple rules for when glasses are needed, but I will try.
If it is green, and it is bright aka leaves spots, you should use glasses, or at least not dwell on the dot.
If it is red, and it is leaving spots, well, thats quite a bit worse. Red can do damage when it isn't leaving spots in your vision.. If you know how powerful a green needs to burn something BLACK, and you have a red that can burn that same BLACK item similarly, assume you need the same sort of protection you'd need if the laser was green.
If you have an infrared laser (670nm+) you just better f@*n know what it takes to be safe OTHERWISE, DON'T MESS WITH THEM YET!!!
If your laser is 445nm blue, you need goggles for any sort of close proximity spot gazing unless you are REALLY underpowering it.
If you have a violet 405nm bluray laser, you should be wearing glasses for close proximity spot gazing unless it is only a few mW to a few 10mW. In my experience, treat the violets like you do the infrareds. In other words, assume the dot is hundreds of times brighter than it seems.
In all these cases, it is assumed to be in average lighting conditions. If it is darker and you don't have glasses, turn the lights on. Things burn the same no matter what the ambient lighting is like.
The most important thing to remember is that the person that wrote this 'guide' has severe damage because he didn't follow this guide to a 'T'. So if anything, err a bit on the safe side.
One other thing, SKeijmel, is that I dispute the usual belief that it only takes one mistake to be blinded. I have caught momentary (~10-50ms) direct exposures from a couple hundred to thousand mW, usually involving letting a friend 'try out' the laser and an unfortunately placed mirror. It hurts, it can cause headaches for days, it causes swelling even. But if you'd have asked me a few days later if my vision was worse, I'd have said "I ... don't ... think so?!?":undecided: In the end, I really wouldn't have noticed. But make no mistake, the damage was done!
Here is a comparison: Go stare at the sun!
No, don't. If your instinct is 'damn, that's bright!' Then stop it. I have a feeling that lasers lose their appeal when you are blind.
So sorry for the really long post. I tried to be concise!
Forgive me for posting again, but my previous post was plenty long enough, and was addressing a different person.
I agree, beam viewing, shows and the sort can't possibly pose any sort of risk unless you are getting the beam shined into your eyes or the beams are kilowatts? (not sure) in power.
It does indeed suck having your eyes damaged, but it is just so subtle, no? I wish the damage was like a splinter in the eye, cause then you'd F@*KN KNOW IT RIGHT AWAY!!!! (okay, maybe I wouldn't rather a splinter in the eye, but that is because I'm a pussy when it comes to pain. A splinter in the finger is bad enough)
Oh, and please don't apologize for rambling since I can ramble with the best of them, and also, when someone rambles, that's when the good stuff comes out!