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Have you hurt your eyes before

U

usakicksass

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I read a report of a person who had IR laser light shining in his eye and didn't know it. Suddenly he heard/felt what he described as a click or pop in his eye followed by blindness.
I read reports of our military guys *ucking with the insurgents by shining IR targeting lasers into their eyes. The insurgents are supposedly scared to death of losing thier eyes by this covert method.
Two girls riding a bus home from school were testing the iris response with a red laser pen. One of the girls had the laser shone in her eye directly for up to five minutes. She recieved a burned retina, a black spot that will not heal.
 





T

Things

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I got ht in the eye briefly by the static beam of my RGY, that wasn't nice. Another one was melting sand with high voltage, THAT was bright, i went off and got some sunglasses after that.....

My DIY red almost caught me out once, but luckily it didnt actually hit my eye, too close for comfort though....
 
S

spyrorocks

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Things said:
I got ht in the eye briefly by the static beam of my RGY, that wasn't nice. Another one was melting sand with high voltage, THAT was bright, i went off and got some sunglasses after that.....

My DIY red almost caught me out once, but luckily it didnt actually hit my eye, too close for comfort though....
Click to expand...

THAT is cool.
 
A

ardyp

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May 13, 2008
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Hello everybody! :)

I'm new to the lasers world and i would like to have some information about lasers risk:

I have a Nova 125mw rated 140mw average, what i would know is how many meters needs the laser to become "safe", what i mean is what is the distance afterward if pointed in eyes is not more dangerous?

I'm not saying i'm gonna point the lasers in someone eyes, but for my safety i would like to know... :cool:



sorry for my english, i'm from italy ;)
 
happytomato

happytomato

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I'd get some goggles if I were you, diffuse (non reflective surfaces) reflections are not really ok. It would be safe shining it in the sky though.
 
Zom-B

Zom-B

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Mar 25, 2008
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ardyp said:
Hello everybody! :)

I'm new to the lasers world and i would like to have some information about lasers risk:

I have a Nova 125mw rated 140mw average, what i would know is how many meters needs the laser to become "safe", what i mean is what is the distance afterward if pointed in eyes is not more dangerous?

I'm not saying i'm gonna point the lasers in someone eyes, but for my safety i would like to know... :cool:



sorry for my english, i'm from italy ;)
Click to expand...
It depends strongly on the amount of collimation of the laser, and the ambient light of the receiver (because the iris dilates). I would however say that it takes at least a few miles hundred meters before it's completely safe.

I made up an approximation formula

(g*e*sqrt(i/s)-o)/d

d=divergence, radians
o=output aperture diameter, meter
i=laser intensity, mW
e=iris diameter, meter
s=safe intensity, mW
g=2 = factor of maximum intensity to average intensity in the entire (gaussian) spot

for example:
Laser:
d = 0.001 (1mRad)
o = 0.003 (3mm)
i = 140 mW
Eye:
e = 0.005 (5mm)
s = 0.1 mW

(2*e*sqrt(i/s)-o)/d = 372 m
 
A

ardyp

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Zom-B said:
It depends strongly on the amount of collimation of the laser, and the ambient light of the receiver (because the iris dilates). I would however say that it takes at least a few miles hundred meters before it's completely safe.

I made up an approximation formula

(g*e*sqrt(i/s)-o)/d

d=divergence, radians
o=output aperture diameter, meter
i=laser intensity, mW
e=iris diameter, meter
s=safe intensity, mW
g=2 = factor of maximum intensity to average intensity in the entire (gaussian) spot

for example:
Laser:
d = 0.001 (1mRad)
o = 0.003 (3mm)
i = 140 mW
Eye:
e = 0.005 (5mm)
s = 0.1 mW

(2*e*sqrt(i/s)-o)/d = 372 m
Click to expand...

Wow that's was i was looking for! Sounds really scientific to me. :)


So you are saying that at 372m the laser will be completely safe? ::)



Thanks for the help ;)
 
Zom-B

Zom-B

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Only when the numbers are correct. If your collimation is better, output aperture is smaller or the receiver's iris is larger, the number increases of course.
 
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