Possible solution to this plane problem

Well, it would be possible to create a coating that has a specific 'notch' for 532 nm, blocking a very narrow band (531-533 would be enough). This would as such not interfere much with observing broader range green lights such as wing makers.

I'm not sure a proper material is available though, getting a sharp notch like that requires atomic absorption.

Also, i doubt i would be used on civilian aircraft, but the military might be interested... if a cheap dx laser gets a passenger jet in trouble, imagine what a big laser could do to enemy pilots... if it's all true

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Or just hope that the criminals are all like these two ones, ROTFL

YouTube - Worst Insurgents Ever

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phoenix77 said:

Not only what YOU said ASHERZ, but the PORT SIDE navigation lights on ALL aircraft, are GREEN, (the starboard are RED). If the windows were coated to block ALL GREEN LIGHT, aircraft would have no idea which way other aircraft were positioned in the sky.
Whether they were approaching, veering away, or any other aircraft maneuver. There
would be all sorts of mid-air collisions & such. I know I wouldn't want to be an airport air traffic controller !!! YIKES, WHAT A MESS THAT WOULD CREATE............... rob
@ TJ, An eye for an eye ? As in the BIBLE ?

Click to expand...

Last I checked it was still Red Port Left, Green Starboard Right.
Easy way to remember "Somebody Left the Red Port wine."

bpace07 said:

Last I checked it was still Red Port Left, Green Starboard Right.
Easy way to remember "Somebody Left the Red Port wine."

Click to expand...

I remember it by the Posh acronym.
Posh types cruising from England to the Indian colonies etc would ride Port Out Starboard Home so land was always visible from their cabin window. These were significantly more expensive seats so only P.O.S.H. people could afford them.*

*might not be true etymology.

@ bpace07, YOU R CORRECT. I just went & checked the NAV. lights on my boat & THEY R as you said, I was wrong. GOOD CATCH, man. I have amended my other posting accordingly. Thanks again for the good eye. rob

Benm said:

Well, it would be possible to create a coating that has a specific 'notch' for 532 nm, blocking a very narrow band (531-533 would be enough). This would as such not interfere much with observing broader range green lights such as wing makers.

I'm not sure a proper material is available though, getting a sharp notch like that requires atomic absorption.

Also, i doubt i would be used on civilian aircraft, but the military might be interested... if a cheap dx laser gets a passenger jet in trouble, imagine what a big laser could do to enemy pilots... if it's all true

Click to expand...

That would be a big pain in the ass to do, not practical at all. Especially for something as large as cockpit windows, and they're curved to boot.

Not practical to have a huge area, narrow-band absorption at exactly 532nm and nowhere else, not feasible in the least.

Heck, even if you did it and had a green absorption at 532, it would also absorb at higher energy/lower wavelength as well, so it would still be absorbing a lot of the light at <532nm as well. Oh, and with an absorption at 532nm, it would also likely have a fluorescence emission at 532nm. AKA, hit the airplane window with a 405nm laser, and the glass will light up green when you do! Imagine how cool that would be, and how many people would try it with violet lasers!

So yeah, not going to happen.

Why absorption ?

You can use holographic mirror coating, tuned for that wavelenght (holographic mirrors can be built for specific wavelenghts, with little tolerances), so anything pass, except the targeted wavelenght, +/- 5nm, that become reflected away.

But at this point your cockpit glasses can cost you a lung and an eye .....

I don't think that would be good for stealth type, military aircraft. Wouldn't that defeat the "STEALTHINESS" ? rob

Stealths uses flat glasses in cockpits for the same reason, basically ..... on a round cockpit glass, you can see a reflection in a wide angle, on a flat glass, you must be exactly in line with the light beam, for see a reflection ..... so, probably isn't a big problem, for them ..... i mean, for become aligned with the reflection of a flat surface that is over the cockpit, you must be over the airplane, at least ..... or the airplane must be in reverse flight

Wouldn't the holographic coating reflect the sun at ALL angles ? BTW, G'morning rob

No, the holographic mirrors reflect as any other mirrors ..... the good thing about them, is that you can make them for reflect only a certain wavelenght, and also on a different degrees angle or geometrical surface of the one of the support (as example, some types of HUD used in airplanes)

As in the HUD example ..... the HUD plates that was used in some hunting planes was placed at 60 / 65 degrees inclination, but was reflecting only the orange light of the instruments placed under them, as they was placed at 45 degrees, and only in one side ..... this way, more or less (a lot schematic )



The examples that you are referring, probably, are due to all those demo holograms that there are around, about mirror-surfaces spheres, where you can see yourself reflected on the surface of the sphere inside the hologram as it was a real sphere ..... i also have a pair of them, somewhere ..... and this is another demonstration of what i'm saying, the simulation of a spherical mirror on a flat surface left you see that you can build an holographic mirror that reflect in an angle independent from the one of the support surface one.

I understand the point that you're getting across. The point I'm trying to make is that it doesn't make a difference WHAT angle the sun is reflected off any angle of the planes windscreen. The fact remains that it CAN be reflected, thereby making the plane HIGHLY visible from a long distance. Polarization of the glass would correct that problem, but what would it do to the GREEN BLOCKING ? IDK, maybe I'm not grasping this problem properly. I majored in Chemistry, never did too well with Physics. LOL. rob

Uhm, yes, about this point, you're right ..... they usually coat anything AR for avoid this, so, the only way for left it AR and adsorb green and left pass all the rest, is probably to change the inside crystal structure at atomic level ..... cause i doubt that an AR coating AND a wavelenght-selective absorption coating can be done one over the other and still work good, not interferring .....

In alternative, you need to find a substance that can be deposited as AR coating, that resist to atmospheric agents and abrasion, that not decompose with the time, that adsorb totally 532nm and left pass all the rest of the visible spectrum, and at the same time, possibly, that is cheap enough so your crystals don't become the 20% of the cost of the whole airplane .....

I don't know if this already exist, i'm not a professional chemical researcher ..... but it sound a damn hell of challenge for me, said in this way

Unfortunately the cost to develop something along the lines that we discussed here would hardly be very cost efficient for commercial or military applications. You know that the only reasonable approach to the problem that the politicos will come up with, put a ban on all lasers for private use. GOD, I hope THAT day never comes. It's always a few A**HOLES that screw things up for everyone else. rob

Lasies (?) and Gentlemen, I believe we have found test subjects for the Boeing YAL-1

@ elewton, what a great idea, line up all the laser abusers, & take 'em out with a pulsed version of the YAL-1, 1 A**HOLE per pulse.
On a side note, different subject, instead of buying 3 sets of goggles, if you could afford them, OEM LASER SYSTEMS ML-7's are less to fuss with. One set of goggles & your covered with CERTIFIED eye protection from any laser you're likely to run into in your laser hobby. Just a thought. rob