US Navy blasts drones with ship-mounted LASER CANNON The US Navy says it has successfully test-fired a ship-mounted laser weapon, and that it plans to deploy the device to an actual maritime staging area beginning in 2014. On Monday, the Navy released video and still images showing the somewhat-unimaginatively named Laser Weapon System (LaWS) firing on an unmanned drone, causing …
These lasers operate in the infrared region where silver paint absorbs, so it's not going to make any difference how shinny the silver paint is in the visible region. A Gold coating may work better but still you would need a surface with a reflectivity of 99.99...% for no real damage to occur.
That may be the case with paint, but how about the 'cat's eyes' type of microprism reflectors found in traffic sigs and such? It should also work at varuous wavelengths, since it is based on total reflection in highly refractive materials...
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"...how about the 'cat's eyes'... "?
It'd still depend on the power --- and the intensity --- of the light. It is not difficult to make a laser with an intensity that it ionises air, let alone anything more solid: I know of one chap who had strategically-placed vacuum cells scattered through what he was doing for that very reason.
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Anyhow, I don't think that the cat would appreciate it very much.
It is not about the absorption or the reflection rate of the target, it is about the power out put of the solid state laser. It is about 100KW laser canons that US navy uses, it hits both the personnel or the sensitive electronics of the enemy targets and causes detrimental consequences, if not the total destruction of targets.
"It is not about the absorption or the reflection rate of the target, it is about the power out put of the solid state laser."
Even the US Navy can't overcome basic physics. It is about the power output of the laser - minus how much of the beam doesn't hit the target - and minus how much of the beam power is reflected by the target, and the effectiveness is also limited by how effective the target is at conducting / absorbing heat....
"I doubt very much that a $5 tin of silver paint would be an effective countermeasure to a $32m frickin laser."
And you'd probably doubt that the watery atmosphere of Eastern Europe would destroy the Stealth coating which cost $Bn to develop.
Except that on at least 1 occasion that is exactly what happened.
Going back to Vietnam the US Army developed the "people sniffer." This was decoyed by a large well filled latrine bucket, wasting several B52 fulls of bombs. Total system nullified by the results of a couple of bags of rice.
Silver paint might not work, but likely a £1 roll of bright aluminium foil (reflectivity 88%) and can of spray adhesive would likely do the job.
Maybe combined with a ceramic coating from the likes of Zircotec for the ultimate in protection...
A laser like this would be incredibly easy to take counter actions against.
The R&D boys might test it but its sold by salesmen to governments and not armies. Stealth bombers are invisible to modern radar but visible to world war II radar but since we dont sell old radar to our enemies they are blind - unless they're looking for reflections of radio ham transmissions.
Australia uses old fashioned, WWII type low frequencies in its over the horizon radar (because low frequencies bounce of the ionosphere, giving enormous range - provided you can unscramble the reflections). Works a treat on "stealth" aircraft, and the Chinese are doing something similar.
I have read the papers and correspondance of people who know far more about this than me...
Basically if you think sunshine reflecting off mirrors, types of power levels - reflection doesn't work with lasers.
Even a super shiny chrome plated spanner will turn seriously hot in the strong sunshine in minutes.
There is an effect that operates on the surface, that silver reflects heat / energy, outwards, but it also reflects sidewards into it's self, at the atomic level, and under really, really enormous concentrations of power / energy, highly reflective surfaces basically offer no protection against lasers.
"Basically if you think sunshine reflecting off mirrors, types of power levels - reflection doesn't work with lasers.
Even a super shiny chrome plated spanner will turn seriously hot in the strong sunshine in minutes.
There is an effect that operates on the surface, that silver reflects heat / energy, outwards, but it also reflects sidewards into it's self, at the atomic level, and under really, really enormous concentrations of power / energy, highly reflective surfaces basically offer no protection against lasers"
I guess you failed GCSE physics. Reflection certainly does work with lasers. In fact most lasers actually contain mirrors in the laser cavity!
The spanner you mention will likely heat up mostly by conduction. If suspended in the air it will certainly take a lot longer to warm up than they same spanner but painted black.
Reflective surfaces offer protection against lasers based on how reflective they are. As an example, aluminium foil would reflect ~ 88% of the energy received, and costs almost nothing, and reflectivity over 99% is relatively easy to achieve. Reflective surfaces are therefore a potentially effective countermeasure against this sort of attack.
As an Aussie and occasional backyard mechanic I can verify that a silver spanner left in the sun gets burningly hot very quickly regardless of the surface it is on. Nope, I don't think conduction through a wooden stool is doing it particularly when the stool is only getting a bit toasty to sit on but the spanner will cause an unwary mechanic to achieve orbital velocities when parking said mechanic's posterior on top.
The sort of stuff you'd make a re-entry heat shield out of would do a splendid job to defending against laser fire. Spinning a missile on its long axis would also work okay, but it does mean that you can no longer use fins to steer.
Thin coatings of highly reflective material would be useless, as they'd be rendered non-reflective in a fairly small fraction of a second. Box reflectors would not remain intact long enough to reflect a destructive amount of energy back at the emitter (though any spectators without laser filtering goggles might not fare so well... see icon).
Anything that uses thermal or laser designation guidance can be blinded trivially, as would any TV-guided devices. Possibly radar guided missiles might work, but I don't know a whole lot about the physical properties of radar transparent materials and whether they can be made usefully laser proof.
Best stuff to use against a target with a practical battlefield laser? Big old-school cannon rounds, or railguns. It'll be weird if battleships come back into fashion, but not implausible. The key word though is practical... most battlefield lasers to date simply aren't powerful enough, and maybe dumb countermeasures will be enough to defend against them in the short term. Maybe. But retrofitting your arsenal with laser shielding is not cheap or straightfoward.
I expect more from my fellow commentards. I would have you know that your average household mirror reflects only 40-60% of light. To achieve 99% you need special coatings and materials which tend to be fragile (think telescope mirrors) and short-lived (think anti-glare coating on glasses). They tend to be very narrowly tailored for the wavelength and so would be easily defeated by a multi-wavelength laser. Even with smoke defense, the energies involved are such that the laser would potentially clear its own path. In short, lasers are much cheaper to build than to defend against.
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Presumably, the enemy's intent is for their missile or plane to reach the ship, which ought to be a matter of minutes or seconds. For such a limited-time need, ablative coatings (such as the heat shields on space capsules like Apollo or Dragon) will likely be more effective than reflective coatings.
Paris, because she's hot and doesn't reflect much.
Don't forget the good old rotation. A missile is computer guided (duh), so it has no problems with rotation.
Put it at, say, 30RPM, and all the heat will be spread over its diameter. Not enough to grant immunity - but perhaps enough to hit the target...
"They named a ship for a *pimp*?!"
No I think it's named after some famous military Merkin.
OTOH Calling it the USN "Pimpstick" would send a whole different message to foreign states.
Perhaps with some nice shiny chrome exhaust pipes on either side of the superstructure.
My coat is a floor length Astrakhan which goes with my Leopard skin pork pie hat.
> "They named a ship for a *pimp*?!"
>
> No I think it's named after some famous military Merkin.
Seriously?
The USS Ponce is named after the city in Puerto Rico (I've been there, it's very nice -- they have a very impressive art museum). The city was named after the the Spaniard who "discovered" Florida: Ponce de Leone.
" No I think it's named after some famous military Merkin."
Well that was my rather obvious guess. US warship, some famous (to Americans) naval figure who no one else has ever heard of.
"(I've been there, it's very nice -- they have a very impressive art museum)."
I did not know this.
AFAIK most people went to PR (or the 51st state as I like to think of it) for booze-and-screw holidays. Like Cuba before Castro.
Not really. The real target for these are not drones. It is non-lethal mode against cameras on drones and eyes of physical personnel on small boats. One pulse and blind forever. It does not take a lot - a few watts (tens of watts at most) @ 1m range are enough to detach your retina or damage a CCD. By the way, navy PR is doing a stellar job in avoiding any further explanations of the "non-lethal mode".
That will not be the engagement mode if NK goes sour. Targets are not going to be small boats with bearded nutters onboard. While some of NK fleet and army is photoshop (tm) it has quite a big stockpile of real weapons including a massive stock of checmical and biological warheads. So there it will be a free for all including proper weapons. Such a toy will have little use there.
They'll just say that the laser is there to dazzle the weapons optics, and that any dazzling or blinding of pilots is just an unavoidable side effect. They already argue that plastic in landmines is to make them hard to find in the ground (legal) and that making the shrapnel hard to find in the body (illegal) is just an unavoidable side effect.
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Maybe because blinder weapons are massively illegal, and the only other people who use them are North Korean.
I don't see why the US has any right to shoot ANYTHING at other nation's drones in International Water, even if they are 'harassing' US ships. One could argue that the US should STFU considering the 'harassment' caused by US drones in Pakistan.
...and the Russians: see the Strait of Juan de Fuca laser incident.
It does not take a lot - a few watts (tens of watts at most) @ 1m range are enough to detach your retina or damage a CCD
It'll take a lot less than that. Tens of watts of reasonably focussed infrared laser shone into your eyeballs will cook them. Permanent damage to eyesight can be done with less than a watt. Lasers capable of pumping out hundreds of kilowatts are incredibly nasty things to be anywhere near at all even if they're not pointed at you.
"Permanent damage to eyesight can be done with less than a watt"
Which makes me wonder what happens when this new fangled laser hits a cloud of old fashioned chaff. Whilst I''d expect it to burn its way through in almost no time, I wouldn't want to watch.
Nope. That only works if you imagine a perfectly spherical cow. In the real world, if you build an airframe that's capable of this, it would be useless for any other task. Moreover, the further it is from the laser, the less effective this would be, as for huge aircraft movements, the laser would only need to make tiny adjustments in positioning its mirror, orders of magnitude smaller than it makes to compensate for waves and ship movement.
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