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Northrop Grumman Markets Weaponized Laser System
stephencrane writes "Northrop Grumman is making available for sale the FIRESTRIKE weaponized laser system. The solid-state laser unit weighs over 400lbs, sends/receives instructions and data via an RJ-45 jack and can be synchronized with additional units to emit a 100 kW beam. It looks like some piece of stereophonic amplification equipment out of the '50s. Or Fallout 3. The press release suggests that FIRESTRIKE 'will form the backbone of future laser weapon systems.'"
So what do we do with all the blind civilians and soldiers then? I assume soon blindness will be fully curable but I also assume there will be shortages so that only people in the military will have vision during wartime?
sends/receives instructions and data via an RJ-45 jack
Don't worry guys, the TSA is working hard on updating their "do not mix with aircraft" list to accommodate this.
Modding me -1 troll doesn't make me wrong.
a sudden spike in sales of mirrors throughout the Middle East.
The higher the technology, the sharper that two-edged sword.
Why.....won't we civilians get laser rifles too?
Light travels faster than sound. This is why some people appear bright until you hear them speak.........
It doesn't sound like an anti-tank weapon. More like a means of frying eyeballs.
So what happens if it is mounted in a suitable high office in New York. You could cripple the city for a while. Drawing the curtains will not help. And the good news is, the operators do not have to commit suicide. The targets are stationary and keep office hours. It could be programmed and left. Visual Basic sounds appropriate.
Yes, but you'd need a tracking system, and a large spinning mirror.
Low Power Setting Provides nominally 100 watt alignment beam
Article is here.
"Alignment beams" are normally low-power (a few milliwatts) visible beams used to indicate the path of an invisible beam. I guess with this one you'd point the alignment beam, move the glowing/smoking spot to your intended target, then hit the big switch.
Distance is the problem.
Focusing a 'low' power industrial laser 2 inches away is 'easy' (given ten years of experience). If I remember right: the electromagnetic field of a high power laser makes focusing impossible at some distance (>>2 inches). As for mirrors, I have an Ikea mirror that can reflect most of an unfocussed 1kW fased or unfased light beam without any problems.
Instead of saying "in any meaningful sense", perhaps I should have said "in the way that you're implying". And instead of saying "all the energy", perhaps you should have said "all the power".
When you say "absorb all the energy and then re-emit it", it does strongly imply processes like fluorescence, or phosphorescence, or even heating and black-body radiation. Simple reflection is very different -- the period over which radiation is accumulated before being re-emitted is effectively zero.
Absent higher-order interactions, the important thing is reflective efficiency, which determines the amount of energy that isn't "re-emitted". It's that lost energy that heats things up.
I freely confess that I don't know how significant higher-order interactions are for conventional reflective materials at these power levels.
The cooling system was the first thing I thought about. I used to work for a company that built prototype lasers for defense and medical applications. We were working on something that could have been an eventual competitor to a laser like the one in TFA. There are lots of commercially available lasers in the 100W-1kW category that are probably similarly designed. Many of the ones that I have seen have a laser "head" which contains all the optics, the pump source, and the laser rod. I've seen ones roughly the size of a toaster. The cooling unit, (which can't be avoided for any laser that I have ever discussed with any of my colleagues, regardless of how much money you have at your disposal to commission a cooling-free one,) is typically the size of a small refrigerator. The problem with solid-state lasers is that the laser rod itself is typically about 3-5mm in diameter and maybe 10-15mm long. The quantum efficiency of the photon conversion process is not 100%. In fact, it isn't even particularly close to 100%. (The quantum efficiency is a function of the laser system in question. For example, any Nd:YAG laser with the same doping concentrations will have the same theoretical maximum quantum efficiency. Nd:YVO4 (wouldn't surprise me if Nd:YVO4 is in the laser in TFA), has a different one, etc.) Whatever light from the pump source isn't converted to photons in the output beam usually ends up being deposited as heat somewhere else in the system. With solid-state lasers, a large amount of this heat gets deposited in this rather small crystal rod. That ends up being the power-limiting factor most of the time. Whatever Northrup Grumman is doing to make a solid-state laser function at 15kW must involve *lots* of cooling. Either the cooling solution has to be really cold, (unlikely -- too much thermal deviation causes materials to change in size too much causing optical misalignment which causes all sorts of nasty things to happen), or the flow volume must be very large, and they must have developed some way to make an unusually good thermal interface between the laser rod and the cooling solution. Another possibility is that they have multiple gain stages, or that they actually have multiple solid state lasers in that box whose beams are already combined. If they do have multiple lasers in that box, then an M^2 of "nominally 1.5" is almost unbelievably excellent. (Unless that figure came from a "hero" experiment wherein they got an M^2 of 1.5 for 3us before it all went south.) (For those of you who want to know more about laser beam quality and what "nominally 1.5x diffraction limited" really means, here is a rather lackluster summary that includes most of the relevant information: http://en.wikipedia.org/wiki/Beam_parameter_product The "times diffraction limited" value in TFA is the "M-squared" number talked about in the summary.) Even with the multiple gain stage option, (which has problems as well), they still need to get a lot of heat out of that box, and they need to be able to control the temperature of the laser rod and most of the stuff that is close to it, which means they can't just connect up some large heat sink (like the body of the vehicle, for instance), and go to town. The temperature needs to be stable. Since they probably aren't running the laser all the time, (presumably they don't want to spend the power having it running and then just open a shutter when they want to melt something -- this would require dissipating all the heat the shutter would be absorbing too,) the cooling system needs to be able to provide relatively little cooling at times, and then lots when they turn the thing on. In fact, it probably needs to be able to heat too, since it would need to be usable in cold weather in a military application.
A lot of research has been done on fiber lasers for this type of application because the heat generated in the gain medium is spread out over the length of a fiber instead of concentrated in a sm