Hi everyone!

So I was wondering if any or our armed forces members could help me understand the use of the M-Frame Laser lens. Standard Issue says:

Laser Strike: Optical Density not less than 4.0 - wavelengths of 820nm to 850nm and the wavelength of 1064nm*. Visible light transmittance: 54% suitable for medium to low light conditions

That doesn't help me at all... My question is... If I'm wearing that lens, what does it do for me?!

Thanks in advance!

Just a guess but if you're using a a weapon with a laser sight it'll enhance the dot on the target. Maybe???

I thought it was to protect your eyes from harmful laser...

Cap'n I'm glad you asked this question. I asked it a few times and never received a solid answer... It doesn't appear that too many people are knowledgeable on this subject.

Looks like I was right, this is what I found:

Oakley is proud to be working with Natick SOF-Special Projects, US Army Special
Operations Command and Naval Special Warfare Development Group to produce
Laser Eye Protection for Elite Special Forces. This represents the Research and
Development for US soldier Specific systems for advanced gear.

I don't remember why, but I have always been under the impression that the laser lens was to shield the eyes from harmful lasers.

Where you at SI brethren?

I thought the same thing. For in case a laser sight accidentally gets shined into your eyes... the lens blocks completely blocks the wavelength of red laser light.

You are right to be confused by the advertisement.
Whoever wrote that blurb doesn't know what they are talking about. The sentence is cut off and/or doesn't make sense.
First off, they mention the optical density, by which I presume they mean epsilon, the electric permittivity http://en.wikipedia.org/wiki/Permittivity of the material is greater than 4. You can't tell anything about the transmission of a frequency of light only given that number since transmission is material dependent and generally non-linear with w (omega - angular frequency). Prescription lenses are made by varying the curvature of the lens in accordance to what epsilon is, as we can see basically by Snell's law n1*sin(theta1)=n2*sin(theta2). There are much more advanced lens maker's equations but they are basically derived from this. We can see that the angle of incidence, reflection, and refraction (transmitted through) depend on epsilon, but this has little to do with harmful laser frequencies being rejected.
Furthermore, the wavelengths they mention don't mater at all because they are all well beyond the infrared (see the image below). I assume that all scope mounted lasers are visible so they can actually see what they are shooting, except for the rare case they are "painting" a target with IR for an air strike like in that Polly Shore movie In the Army Now, but that's likely to only be harmful to the eyes if you stare right in the barrel. Laser classes are designated by human blink reflex and the amount of time a laser of a certain power would take to injure the eye. Invisible lasers (like IR and UV) are where the real problem is, but all plastic is opaque to UV, and glass and plastic is opaque to IR. I've worked in quite a few labs with high powered lasers, and other UV sources and cheap plastic safety glasses work just fine.

That's very extensive! I actually understood some of that! Thank you science and physics classes from college!

I took the lens and shined a red laser pointer through it, and you it did not block the laser going through the lens. Luckyily I didn't have them on while doing this... haha.

Well, hopefully some of our SI pals have an answer, maybe some experiences from their useage! It's a pretty interesting lens!

My understanding is it blocks the green lasers used for "target marking" as apposed to the red lasers seen on most scopes. Apparently those types of lasers can burn your eyes, the laser lens blocks this.

OR

It allows you to see the "target marking" lasers.

I honestly cant remember which it is and the more I think about it the more I confuse myself. I will try and look it up.

I disagree - it would be extremely difficult to manufacture glasses that reject a narrow band of frequencies, though apparently some lenses have been made, but they are very expensive: http://www.edmundoptics.com/onlineCatalog/DisplayProduct.cfm?productid=2432
As far as making thermal targeting lasers "visible" - definitely not. You'd need frequency multiplier photonic crystals, and I think those are large and powered. Again only exists in laboratories or telecommunications equipment.

I have a few different pairs of laser protection glasses. (I'm a bit of a laser hobbyist. I use violet lasers, green lasers and red lasers. Would like to get into some of the blue lasers and yellow lasers eventually, but prices are really high right now.)

You can get protection glasses that, when compared to oakley pricing, isn't really that high. ;)

Here's a forum to check out a few glasses:
http://laserpointerforums.com/f53/any-multi-wavelength-glasses-44727.html

Mike

And I always thought it meant that the lens shot lasers.

I'm a bit of a laser hobbyist

My favorite quote of this thread thus far. I never knew...

Here's some of my laser pics. Door to the lab:

and the large orange thing here is our laser:

Don't hump the freakin laser mini... HA HA HA

I am not quite sure what exactly they do. Even if you wear them and shine a laser pointer at them it will still leave spots in your eyes. It may filter out some but if it totally blocked the laser then we wouldn't ever be worried about enemy's having laser blinding weapons yet it comes up in the news here and there.


and that is a fricken sweet laser you got there..

So here is the deal. The lens dose indeed protect the eye from certain wavelengths of lasers used the military. The tech data is proprietary (classified) per the request of the US government so that is why it is practically impossible to get any specifics out of anyone. This info came directly from someone inside the Government Division of Oakley. I was told if you have the proper security clearance you can get more information by calling Government Sales directly.

That looks like the lab from Real Genius!

I've got a TS clearance. I'm an MI guy. I'll call on Monday and see what I can dig up. Of course, if I tell any of you, I might have to kill you.

but then they will throw out the famous "need to know" clause and say no

People, I can't believe no one else knows. They are to protect against the optic blasts from the Cyclops Ruby Juliets and Pennies.

Well if it's classified, it's still pretty easy to get the specs. All you need is a spectrometer and a calibrated light source to see what gets transmitted. I assume the results would look like any other piece of clear plastic. How much do these glasses cost?