While laser guns are, for the most part, pretty far from becoming a common military weapon, we could see them on the battlefield in the near future.
The U.S. Defense Advanced Research Projects Agency (DARPA) recently received permission from the government to begin field testing its HELLADS laser weapon. "The technical hurdles were daunting, but it is extremely gratifying to have produced a new type of solid-state laser with unprecedented power and beam quality for its size." DARPA's Rich Bagnell said in a statement.
The agency has been working on the HELLADS weapon for over 12 years. The project is supposed to "develop a 150 kilowatt (kW) laser weapon system that is ten times smaller and lighter than current lasers of similar power, enabling integration onto tactical aircraft to defend against and defeat ground threats." This laser could be used to take down missiles while in the air, and it could also be used as a highly-precise offensive weapon for taking out targets while minimizing unnecessary casualties.
While these possibilities sound good, the laser is still too heavy and expensive to be mounted on a drone. DARPA hopes to shrink the laser down more so that it can be used as an offensive weapon on UAVs and on fighter jets.
Military developers currently believe that the HELLADS laser would be a perfect weapon for the ASI Avenger drone. Russia Today noted that "the drone's jet engine is capable of producing enough energy to recharge the laser's battery in flight, essentially giving the weapon infinite ammunition."
DARPA has not released the exact date for when official field tests will begin.