Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

Buy Site Supporter Role (remove some ads) | LPF Donations

Links below open in new window

FrozenGate by Avery

Slightly crazy 980 nm laser experiment

Status
Not open for further replies.
T

Trajork

0
Joined
Sep 30, 2010
Messages
12
Points
0
I've recently gotten into cheap lower-powered lasers, and I'm interested in the limits of human vision. To that end, I just bought a 5 mW 980 nm laser off the Internet. As I understand it, looking directly into lasers of that power for a time on the order of a few seconds should be fairly safe. If I do this with the laser I just bought, what do you think will happen?

Possibilities:
-I see a red light when I shine it into my eye.
-980 nm is totally invisible, and I see nothing.
-I fry my eye, due to some difference between the 650 nm lasers that are virtually harmless and 980 nm light at the same intensity
 





If I were you, I would not point a laser of any power directly into my eyes. The truth is that even if the laser is advertised as 5mw, there's really no way to be sure. Especially since it's 980nm, it probably won't be that visible. If I were you, I'd point the laser at a sheet of paper and see if the dot is visible. No point in risking your eyesight.
 
5mw is safe for visible lasers because the blink reflex kicks in to protect your eyesight. It can still damage the eyes, permanently. It just does it slower then the typical human blink reflex kicks in. With 980, if you can't see it well, or at all, then the blink reflex won't be kicking in. Perhaps it's less damaging to the retina then higher wavelengths, perhaps it won't still fry a small hole in your retina. Then again, perhaps not. You really want to take the risk? Remember, even a small hole in the retina will cost you a chunk of vision. Forever. And if the retina detaches, it can cost you all of that eye's vision. Forever.
 
Thing is, I've looked up examples of vision damage from 650 nm lasers and it seems that the only way people have ever damaged their vision from those is by forcing their eyes open and staring at them for minutes on end, and even then literally every one of them recovered full vision within a few weeks. I'm aware of the blink reflex issue, but it looks like it has to be overridden for visible light to cause damage, so I don't know why IR would be any more dangerous based on that. By the way, what's the maximum permissible exposure to near-infrared light? Maybe I could calculate the longest safe exposure time, assuming it's really 10 mW instead of 5, and limit myself to that? (and the experiment won't happen if I get some result <1 sec or so)

edit: The first thing I'll try will be to see if the dot is visible on paper or a wall; this more dangerous experiment will happen if I don't see anything from a diffuse reflection.
 
Last edited:
If you are going to do something potentially dangerous like that (who knows if that pointer is really overspec 50mW?) at least try it by pointing it near your eye instead of into it. The obvious answer though is just don't do it.. You wouldn't point a potentially loaded firearm at your face would you? Lasers need to be treated with respect and caution, once you stop being afraid of their potential consequences is when your safety practices will slip and accidents will happen.
 
And here i come again DONT aim in your eyes even it's a 5 mW cause i used to have a 5 mW red and on 1 eye i have still see the damage it did to my right eye ( 15 years ago )
5 mW is still enough to do damage so take the sheet of paper.
 
Last edited:
Shining a laser into your eye? You're an idiot to even consider posting this.

I smell troll...

M
:)
 
1. The blink reflex will not protect you from IR light, because your eyes can not see it, therefore it will not trigger the blink reflex
2. lasers do come over spec and can cause permanent eye damage even at powers less then 10mw
3. the Maximum permissible epxosure is less <5mw you idiot... its not a meaure of length of time.
4. This is idioitic, and laser pointed into the eye will cause damage one way or another. To do so is 100% not safe, and frankly quite stupid.

Lastly GTFO troll...
 
Trajork said:
I've recently gotten into cheap lower-powered lasers, and I'm interested in the limits of human vision. To that end, I just bought a 5 mW 980 nm laser off the Internet. As I understand it, looking directly into lasers of that power for a time on the order of a few seconds should be fairly safe. If I do this with the laser I just bought, what do you think will happen?

Possibilities:
-I see a red light when I shine it into my eye.
-980 nm is totally invisible, and I see nothing.
-I fry my eye, due to some difference between the 650 nm lasers that are virtually harmless and 980 nm light at the same intensity
Click to expand...

Are you out of your F@#king mind...
How do you know for a certainty that that Laser is 5mW and
not >5mW...

Just pondering your question leads me to believe you don't
have the equipment to verify your Laser...

You need to do a lot of research and reading...IMO

You are either very stupid or a TROLL...


Jerry
 
weeba2kv said:
And here i come again DONT aim in your eyes even it's a 5 mW cause i used to have a 5 mW red and on 1 eye i have still see the damage it did to my right eye ( 15 years ago )
5 mW is still enough to do damage so take the sheet of paper.
Click to expand...

What is up with your avatar, are really shining that at your face?

avatar20902_1.gif
 
eh yeah it's 50mW green , maybe i should remove it change it cause people might do the same as i did once...
 
Last edited:
Didn't exactly expect anybody to think this was a good idea, but believe it or not experiments of this sort have been done (Sliney et al basically tried this, and didn't hurt any of their subjects). But they obviously had much better equipment, and even a 5 mW laser appears that it would deal out easily 10+ times the MPE for an exposure even in the 0.25 s range now that I look up that information.

So I'll propose something marginally less stupid than my original idea: glass has a reflectivity of around 4%. If I were to look at the reflection from a glass surface, I should be able to reduce the amount of power entering my eye by a factor of ~25. Granted, still probably above the MPE, but could that reduce a class IIIa laser to more like a class II? I know it'd still be really risky, but does it seem likely that that would cause injury?
 
You guys think every one is a troll... Maybe he is just not the brightest light bulb. you could try un focusing it as well if you do decide to do the dumb thing

I would advise not to do it. Try:
1. turn shower on hot an close door and windows and look for beam and/or dot.
2. Use incense instead and do the same.
 
Trajork said:
Didn't exactly expect anybody to think this was a good idea, but believe it or not experiments of this sort have been done (Sliney et al basically tried this, and didn't hurt any of their subjects). But they obviously had much better equipment, and even a 5 mW laser appears that it would deal out easily 10+ times the MPE for an exposure even in the 0.25 s range now that I look up that information.

So I'll propose something marginally less stupid than my original idea: glass has a reflectivity of around 4%. If I were to look at the reflection from a glass surface, I should be able to reduce the amount of power entering my eye by a factor of ~25. Granted, still probably above the MPE, but could that reduce a class IIIa laser to more like a class II? I know it'd still be really risky, but does it seem likely that that would cause injury?
Click to expand...

What is the actual purpose and need for you to shine
a LASER BEAM into your eye...:thinking::thinking::thinking::thinking:

What will you accomplish by it...:thinking::thinking::thinking::thinking:

Don't you know that your eye has a lens that will
focus the beam onto your retina...:thinking::thinking::thinking::thinking:

Like was referenced above... even a pointy
stick will work if your objective is to damage
your eyesight...

To even mention wanting to shine a Laser into your
own eye on a Laser related Forum is Moronic..

If you want to look into the Laser's aperture.... Shine
the Laser into a camera and record it or watch it on
a monitor...


[EDIT]
@ toaster.....
If you have no real life Facts or experience...
I wouldn't be giving Laser Related Safety advice like that...

Toaster said:
You guys think every one is a troll... Maybe he is just not the brightest light bulb. you could try un focusing it as well if you do decide to do the dumb thing

I would advise not to do it. Try:
1. turn shower on hot an close door and windows and look for beam and/or dot.
2. Use incense instead and do the same.
Click to expand...


Jerry
 
Last edited:
Status
Not open for further replies.


Back
Top