Laser Air Defense

Neat. [Link]

It had been accepted wisdom in the laser community that 100 kilowatts was the minimum power required for battlefield-strength blasters -- a level that hasn't been hit (yet). But in these tests, the Raytheon crew managed to zap a couple of mortar rounds, using a bundle of fiber lasers that only had 20 kilowatts of power. Not only that, it's beam quality was terrible: Spread out all over the place, instead of in a nice, tight spot. So how did they pull it off? It turns out that the laser's weakness -- its lousy beam quality -- was also its strength. By spreading out the laser's spot, the weapon has able to heat the mortar up -- and cause it to explode. Think of it like an explosive potato, left too long in a laser oven.

After a couple of years of engineering, Raytheon is now trotting out "a prototype Laser Air Defense System (LADS)." It's a modified version of its Phalanx mortar-shooter, already deployed in Iraq. Except, this one uses 50 kilowatt fiber laser bundle, instead of traditional ammo, to knock down its targets.