Fiber is an excellent choice for getting those photons flowing. The new Prune based lasers also promise to be a low-cost over the counter remedy.

Do they come in Good Guy Blue and Bad Guy Red?

Nice to know they want to plaster airplanes that just come over the horizon all over the ocean. I guess its lost on these folks that if you have good intel as to where your target is you can launch from much further away than within sight. In this modern era the seeker heads in these weapons can find targets if they are launched in their general direction. If the ship has this new laser system, its just a matter of launching that many more missles at the ship. I suppose it would be great in Iraq to explode roadside bombs... now.. all we need is a way to FIND roadside bombs so that he laser can explode them. I guess DARPA doesn't think of that sort of thing though.

With high powered lasers... what happens if someone takes a shot at at something and misses? What kind of range might these weapons have?

My mind is wandering off to delusions of a misfire in the middle east bouncing off important satellites solar panels (sending it tumbling out of orbit) and some poor guy in Boston getting the hot-dog shot out of his hand by the ricochet as he casually pays some street vendor...

But seriously... Range? Will a laser skip in the atmosphere like some radio waves do? Will it continue out indefinitely into space hopefully dissipating before shooting the 'dog out of some martians hand light years from now?

...But I'll be really impressed when I'm holding a lightsaber. Comeon DARPA, if you're gonna build sci-fi weapons, build cool ones!

I guess the arrangement is that DARPA build tools that sound vaguely interesting, or potentially useful, and someone else figures out how to use them.

Accountants don't quite get that, which is why you need "possible uses" - they are not intended to be REAL use cases - they are just there to get the funding! The real applications can be figured out later.

After all, nobody thought liquid crystals with odd optical properties were going to be much use for anything, and look how that turned out.

... that all these energy weapons be made mandatory for any battlefield, and projectile based weaponry banned, conversely. Soon we would see troopers chasing each other around to screams of "bang, you're dead!", "no, you missed!", "no fair!" and the like, sometimes employing interpreters.

Hmmm, and then someone will dig out that old 15-inch naval gun and no laser will ever stop a projectile from that one, for sure!

However, such special cases aside, a laser gun will definitely change the way wars are fought. Sooner or later practicable laser weapons will be developed - it is just a matter of time.

Misfire or mis-aim, I don't think the chances of accidentally hitting a coms sat is too high. However, what are the chances of laserfire skipping off a thermal inversion layer the way mirages do and then remaining strong enough to do damage elsewhere?

As far as LCs go ,I had samples from Ciba-Geigy in the late sixties for looking into the possibilities of colour TV screens. Unfortunately I never persevered with it.

There is too much energy in the beam to be bounced of an inversion layer.

Likewise if the beam would survive on a trajectory to the nearest satellite and have enough energy to damage it not enough of the beam will be reflected to toast someones hotdog.

That said the beam will only have 10 to 20 miles of effective range (in case of the 100KW one) in the best of circumstances and effective range will drop faster the more pollutants (smog, fog, sandstorms, evaporation/rain, etc) there is in the air.

So what happens if one of these high powered lasers hits something shiny - like a mirror or cats eyes? Won't enough of the beam come back to destroy the sender.... Talk about shooting yourself in the foot...

& when all the grunts are armed with portable versions of these tools, they'll be flashing at each other all the time..... Just about shows what the US military is going to become, a buch of flashers, led by a jerk of a president...

I wonder what the effect on foliage will be? A bit of leafy removal - or a really burning Bush?

blowing missiles out the sky and stuff is all very well, but surely the only worthwhile goal is to make something powerful enough to be able to write your name on the surface of the moon with, no?

http://www.omgwallhack.org/media/img/joe/chairface-moon.jpg

“Instead of that you could carry a blaster weapon which might deliver 3 kilowatts to an enemy soldier. Depending on beam characteristics, atmosphere etc. that might be somewhat like pressing a steam iron against him. Nasty, but in the end you'd probably rather have the ordinary rifle.”

Collimation is the key component this author missed.

A well focussed 3kw laser will do plenty of personnel damage and will drop a person much quicker than any iron, even when flung.

A laser gun inherently comes equipped with a silencer too.

Sure, just 3 kilowatts, just like your steam iron.

Except, those three kilowatts of energy are spread over how many square millimeters, did you say?

Make the math experiment of calculating energy in watts per square mm, and you'd be suprised at how much stopping power a 3 kilowatt laser has. For your information, an 8watt ion-argon laser is superb for igniting things on the other side of a city, given a few minutes. That's 8 watt, not 8kilowatt. And an ion-argon laser has most of its output in the blue-green end of the spectrum, not in the IR spectrum (like a Carbondioxide laser would have), and hence has less warming (and more illumination) capabilities.

//Svein

Its just how much Real Power (joules of energy) is concentrated over a specific area in a specific period of time. (I really hate it when they lie with numbers by using watts of power as opposed to real energy levels)

It is sort of like the difference between a hovercraft and a stiletto heel .... one will run over the arch of your foot with no problem for you, the other ..... >.<

Let's all put our retainers in and call 'em what they are:

Phasers.

Pronounced Fay-zherzh.

"Scotty! Bones! Set phasers on "Annoy"! It'sl burn 'em like a hot steam iron!"

A 3kW tactical laser weapon in the hands of those good ol boys , with their penchant for friendly fire.

A couple of test runs and then it's

"hey you damn mothers, anyone tell me why my sonofabitch sat nav will not find any sonofabitch satellites"

Oh, Oh, Oh, can you feel the FARCE ?

The current "State of the Art" battery technology in terms of capacity is Lithium-Ion Cobalt, with a maximum energy density of around 190Wh/kg = 684000 Joules/kg

Assume that a 1-second burst at 3kW incapacitates an enemy combatant.

So to take out one soldier, you need 3000 J

If the LASER is 100% efficient, you get 228 shots per kg of battery - not bad!

But LASERs are closer to 5% efficient, if not lower - thus you need to put 60kJ into the device for each shot.

11.4 shots per kg of battery... not so good.

maybe they can add a handcrank, a few cranks gives you a shot, "zap zap crank"

seriously, i think these are more aimed at things that carry thier own power supply, like tanks and humvees and aircraft carriers. i suppose they could go ghostbuster on us and strap an un-liscensed particle accelerator on their backs... but hand weapons i think are out untill there is a major battery breakthrough.

Could not one of these "doomed" jets simply have 1) radar, having a good idea of where such potential large laser guns are, 2) angled fuselages, with such materials that could deflect laser which are, after all, electromagnetic radiation - ? Ostensibly soldiers could wear reflective gear, scattering much of the laser light, possibly back in the shooter's eye.

And to above, ion-argon? Is that a fiber laser?

Next, do we know the efficiency of fiber lasers? 5%?

What of ultra-capacitors for laser discharge?

Not to poop on the party, but I'd rather we in the states didn't send so much of our tax revenue to DARPA, so they can blow it on anything remotely related to the military. A lot of things discovered in 'unrelated' research prove to be useful in times of national defense. Read about Chime Wiseman (sp?). You can't accurately predict what'll be useful in a future fight, i.e., this is highly inefficient funding - the Pentagon would probably get more useful, novel weaponry and such by funding general research.

But maybe it all makes for a good show to boggin-bloggers outside the states...

Modern high-power IR semiconductor lasers typically run at up to 50% radiometric efficiency when used at rated power.