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U.S. Developing 100-Kilowatt Laser for Strike Fighters
redwolfoz writes "New Scientist reports that American defence contractors, Lockheed Martin and Raytheon, are developing a 100-kilowatt infrared laser weapon for the F35 Joint Strike Fighter that may be powerful enough to blind people on the ground, even if they are relatively far from the target."
I was always under the impression that a kilowatt laser wasn't that impressive
you have been watching too much real genius. one of my friends works with a multiple-laser mass spectrometer over in atmospheric sciences (the Single Particle Laser-Ablation Time-of-flight Mass Spec, SPLAT-MS, if you're curious) - they have a 1.5 watt, 20ms pulsed CO2 (infrared, same wavelength range the military wants to use) laser that will cause third-degree burns if you put your hand in the beam for *two pulses*. now this laser they're talking about is a 100kW; i don't know if the solid-state is less efficient than the gas laser, but either way there's still going to be a lot more than 1.5W coming out, for a lot longer than 20ms. i'd like to see what happens if you blast a chunk of asphalt with that sucker - the SPLAT laser makes little firepuffs of burning tar vapor; the military laser would probably "ablate" (vaporize) the entire rock. and to ice the cake, IR laser emission is totally invisible, even the scattered stuff...
Facts do not cease to exist because they are ignored. - Aldous Huxley
Here. Also being considered for the AC-130 gunship. Explanation of aiming problems, one turret or two, etc. Much more detail.
Infuriate left and right
The calculation isn't an easy one, as there are a number of factors involved:
* Is this near infrared or far? A CO2 laser will put out far IR, with a wavelength of 10.6 microns. At that wavelength the light will damage the cornea, and possibly the lens of the eye. Near IR (under 1.4 microns) will damage the retina, possibly causing a foveal blind spot.
* Specular or diffuse reflection? The big problem with lasers is that you have a serious amount of power focused in a very collimated beam, all of which can get focused into a very small part of the eye. It's a question of intensity -- power per area. Diffuse reflection will send the laser power all over the map, but less of it will get in the eye. Direct reflection won't be spread out over as much of an area, but if it gets in your eye, eyoikes.
We're talking 100 kW, which is a giant dumptruck full of power. A 100-watt CO2 laser, which is nice and invisible, will give you serious burns with a beam that's a centimeter in diameter. Now imagine focusing that power down into your eye. And that's three orders of magnitude less power than this 100 kW laser.