405 nm LASER SAFETY

[The_Doctor]

Oh, you don't get a sunburn from 405 nm by the way. You need UV-B to activate that mechanism. You will indeed darken existing melanin though, giving you something of a tan.

I meant a heat burn in this case.. Also, I agree, existing melanin seems more likely, I got the impression that any small moles that were new might likely be enhanced by this, not created, if affected by it at all. (There is controversy about whether UVA also causes sunburn in tanning lamps but I agree that UVB is the one to do it).

I'll read up on free radicals. I've heard of them, but not looked deeply at them. I normally eat a diet high in antioxidants though, I chose sources that I know are good, usually fresh meat, or tinned fish, and lots of fresh fruit.

Steve, I agree that the Arctos thing with a lots of 405 nm diodes might be enough to tip the balance obviously, even scattered light will be strong at several feet then. Until then it might be worth looking at UV LED's as used in arrays to replace lightbox fittings for PCB exposure and such. Those are common enough that there might be some correlation between reported medical problems and use of those. I wouldn't want to have to find that scattered evidence and collect it though. All I know is that there is enough similarity in output to consider looking there, and there are lots more of them already.


Pat(?), I bet you're right, that it is related. People who work in labs don't usually get cataracts like people working all day in bright sun do. Not so far as I know, anyway..

[DZ]

Hmm, this has been a great thread about the 405 lasers. I know that you can do something rather stupid now and end up paying for it 20 years later. It gives me enough concern to dismantle the 405nm pointer I have until it is proven beyond the shadow of a doubt that there is no harm. Steve, thanks for bringing this up, it has been very informative.

[Things]

Putting aside the total morons out there with lasers, I dont think the amount of exposure a average hobbyist, to a 405nm laser, would cause such serious damage. sure, you should be using goggles, to protect your eye's, but with most people its *click on* light the match *click off*

If they start pointing it on their skin and in their eye's, that is harmful with any laser, in which case isnt really a problem with the wavelength, but with the user. If you shine a laser on your skin, and it starts to hurt, most _regular_ people would take it away, or not even do it to begin with.

Shining it in your eye is just plain stupidity.

While I do agree with what has been said in this thread, I dont think the AVERAGE hobbyist gets enough exposure time to be any different from other lasers.

I know there are alot more people more experienced in the field than me, here , just my opinion

[DZ]

You're probably right, and I hope you're right, but to me it's enough of a concern to discontinue using mine for now.

[dar303]

I accidentaly got a 405nm beam of around 100mW on my hand while adjusting the dichro on my projector. It left a tanned streak when I moved my hand and it was visible for a couple of weeks. I had the hand in the way for maybe 30 seconds to a minute. I't didn't hurt so I didn't notice it until the day after.
I won't do it again!

[Xytrell]

Would even diffuse viewing of a 405nm dot even if done fairly often surpass the exposure of a seasoned construction worker from the sun?

[mixedgas]

Would even diffuse viewing of a 405nm dot even if done fairly often surpass the exposure of a seasoned construction worker from the sun?

probably not, in the long term. But 405 is so poorly researched its not even funny.

Steve

[QUAZAR]

Just found this document on 400nm laser radiation. Might be usefull to you.

[Agent C]

I'm in vision research too - specifically age-related macular degeneration - are you at CWRU, Steve? I will pull a few papers and post references to where the 457 or 488 line of an argon laser administered to animals with high cholesterol in diffuse, non phototoxic (ie not hole burning) doses caused rapid oxidative damage and degeneration of the macula. This was done not to assess the danger of 488nm light but to quickly model in a few weeks a process that takes a lifetime in humans.

Blue and UV light causes oxidative damage to retinas. I think the closest you'll get to evidence is if somebody finds that using a 405nm diode laser in their experiments works 10 times better than a 488nm argon. BTW, smoking is the number one risk factor associated with macular degeneration and vision damage, so if you're worried about your retinas stop smoking first.

[platinum]

Good thread. I'm glad I gave my 405nm to Evil Adam. He can go ahead and deal with the possible macular degeneration instead of me!

I did notice while I had it, something in the back of my head was putting up red flags when I was hit by glare from walls when shooting it in the dark.

It was sort of scary thinking about how much power it was actually putting out compared to how much light I was seeing with my eyes.


Another 'thank you' for highlighting this issue Steve.

-Jonathan