Posted on 07/26/2015 12:44:12 AM PDT by lee martell
Ban assault lasers.
Post “Laser-Free Zone” signs around airports.
I’ve seen an attack as a passenger on an AA flight.
On approach to MIA.
Pilot was talking to flight attendants about it as we deplaned
Green laser
Polarized sunglasses?..............
Re polarization: The amount of polarized light transmitted through a polarizer varies with the cosine of the angle between the polarized light and the polazrizer orientation. You do not get a deep null unless they are exactly perpendicular to each other. Most of the time, roughly 50% will come through, since the relative orientation will be random.
The reason polarized sunglasses are good for glare is that the reflections from snow or water tend to be predominantly horizontally polarized, while the glasses are oriented with vertical polarization, and the perpendicularity condition is met.
“and there’s no single goggle or windshield coating that will block all types of laser.”
Actually there is... A high definition LCD screen with redundant external cameras. Drones are flown that way all the time, and I’ve actually flown such a craft with LCD goggles.
“Develop technology that will pinpoint the laser source then shine a laser back at them bright enough to stun and blind them so that they can’t see for hours.”
That’s called a corner cube retroreflector:
https://www.youtube.com/watch?v=YQ4SnBa7bj4
Via laser guided munitions?
On polarized windows. A laser light aimed at an aircraft above can only come from a certain range of angles, correct? So the polarization need only to be for certain angles and that would take care of most likely scenarios.
Yeah, I’m still not sure about the angle available until damn close to below 500 feet or something without a higher elevation from the pointer to the aircraft. Bendable laser pointers? Glass bottom cockpits? Angle of approach of the aircraft? Normally a little nose up right?
I'd say that's partially correct, but not good enough to achieve the kind of reduction you'd want--a factor of 99% blockage. The angle I was talking about wasn't the angle of incidence between the beam's travel and the airplane window, but rather the difference between the polarization angle of the beam relative to its own path, relative to the polarization angle of the polarizer in the window (or in the pilot's glasses).
The key here is that the polarizer doesn't provide a deep null unless the alignment is right, very close to perpendicular...otherwise, it's partial blockage, and not to the degree I think is needed, as lasers are very bright. Since the transmission is roughly the cosine of the angle of difference, you'd need to be within approximately 1/100 of a radian (about 1/2 degree) to get 99% absorption.
Reverse laser guided missile should do the trick, spectacularly.
A phase-conjugate self targeting laser system matching the offending laser frequency would be an effective response. The beam energy from the ground laser acts as a pattern to be amplified by an airborne laser, which would then send a return beam in the kilowatt range directly back into the ground based system emitter. The hand holding said laser may suffer collateral damage.
That will block out ALL of the light, leaving the pilot blind to the entire spectrum.
The polarization of the beam depends on the rotation of the laser pointer about its long axis, not the angle the beam differs from the tangent to the earth. You would have to pass laws making people rotate their pointers to the safe position. I suppose the manufacturers could put a dot on the pointer's body, with a note the says, "This side up". Of course, compliance would be an easy matter to enforce.
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