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Get Some Safety Goggles Now!

BowtieGuy

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Hey Pi, I think you are correct on your math.
I think a quality pair of OD 4 would be fine.
 
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bobo99

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I think your math is off by two zeros, someone correct me if I am wrong, doesn't OD 4 reduce the light to 1/10000th and OD 5 to 1/100000th, I am sure I read this somewhere. Or am I off by one zero?

Anyway OD 4+ is good enough for a 3.2W laser, at least for viewing the dot up close, but at 3.2W I wouldn't trust just any glasses to protect from a direct hit.

Alan
Something seemed off. I was using the equations from here:

Certified Laser Safety Glasses

Confused the 0.001% with actually reducing it by 1/10,000th when it fact,
OD5 reduced by a factor of 0.00001, 1/10,000, 0.001% or a 3.2W laser to 0.032mW or safe levels. It's one of those days.
 

Bionic-Badger

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The equation is:

I_out = I_in * 10^{-x}

where Iin is the input power, Iout is the output power, and x is the OD.

OD 4 --> 10^-4 = 0.0001. I_in = 1W --> I_out = 0.1mW

For green lasers, the OD of goggles such as ARG-type goggles may seem really high (OD7), but it makes it a lot easier to work with for aligning and stuff.
 




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