Boeing's Enormous Navy Laser Cannon
An anonymous reader writes "Boeing is working to build a huge, incredibly powerful, soon-to-be-seafaring laser for the US Navy. This free electron laser can produce light of any wavelength (ie, color) directly from an electron beam, and gets an energy boost from a superconducting particle accelerator. Once it's onboard ships, the laser could be used to shoot down cruise missiles and artillery shells."
It's difficult to make a reflective coating that reflects well enough at a broad range of frequencies. The mirrors in the laser usually only work that well at one frequency, and they have cooling systems built into them. They also aren't moving, don't have weight limitations and don't have to deal with weathering and dirt.
It's also hard to make a reflective coating that reflects well enough in all directions that the laser can hit from. Your missile has to be able to home in some way. If you have IR windows for a seeker, that's an area that isn't very reflective.
You just have to get a tiny area burnt through and then the energy from the laser will heat what's behind it so much that it'll blow the rest of the coating off or mechanically disrupt whatever the coating is on.
It can help. A little. And it adds weight and problems to the missile. It's been looked at for some time and found not to be a cure all by any means. It sounds like a good idea, but turns out to not be terribly practical.
Same for the old idea of spinning an incoming missile to distribute the energy. That one is about like pirouetting in front of a shotgun. The energy comes in way faster than a mechanical movement.
Yes, I'm glad that defence contractors and the military are still pumping tons of money and research into these ridiculously expensive, fragile, and unwieldy toys while American families are increasingly going homeless and dying from third-world diseases because they can't get healthcare.