Rusty` got it, just about!
It is indeed the Laser Area Defence System. It is based on a solid state fibre laser of some 20 kW. It isn`t a pulsed laser, the beam is held on target constantly until it is ruptured. Talk is of a range of 550 yds. A real deal ship mounted system is 2 years away according to Raytheon. They will need a hell of a lot more power than 20 kW to give it a decent range. I guess that is what Integrated electric propulsion is for then! The box on top of the Phalanx mount is the actual laser.
I am not convinced they can overcome dust/fog/humidity issues though...
Both Northrop and Raytheon are big players in these types of weapons nowadays, along with TRW etc.. Sandia lab`and Lauwrence Liv` probably do a bit of work as well!
A Laser Phalanx?
Lasers go to war | www.azstarnet.com ®
Raytheon Tests New Laser Weapon