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Laser glasses

Death Ray

New member
Jan 26, 2022
Hi guys, help me if im wrong,
Class I and II laser no need glasses = under 5mw.
Class III laser yes = over 5mw.

Now i know how to choose the wavelength, but i don't know how to choose the OD safety level, because i don't know how to compare the laser output and power to the right glasses... So i'm actually using this logic...

OD1 = 10^1 = it means that light is x10 times less bright.
OD2 = 10^2 = it means that light is x100 times less bright.
OD3 = 10^3 = it means that light is x1.000 times less bright.

So the goal is to keep the light power same as the light that can produce a simple laser pointer """"under 5mw!!!""". Because we can immagine that lasers under 5mw """no need glass protections""".

for exemple: 1.000 mw laser/1000 = 1mw. = It means that if i wear an OD3 glasses i can see the output as a simple 1mw laser pointer, and that should be enought, and it's not possible that if the bright is x1.000 times less it can still make you blind... I think that """with the right wavelength glasses""" the brightness is directly proportional to the output power.

Sep 20, 2013
If you removed the decimal point in your example in the last paragraph then that would make more sense. A 1.0000000000 mW laser IS a 1 mW laser all by its lonesome. This type of question comes up so often there are threads with many posts that will answer any question you might have. Good luck.
Jul 10, 2015
OD 0.0 = 100% Transmittance
OD 1.0 = 10% Transmittance
OD 2.0 = 1% Transmittance
OD 3.0 = 0.1% Transmittance
OD 4.0 = 0.01% Transmittance
OD 5.0 = 0.001% Transmittance
OD 6.0 = 0.0001% Transmittance

Note : Make sure you look at the coverage graph for your glasses.

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