4 ms·

Laser gun fired from US navy ship

14 points by miraj 16y ago

michaelcampbell 16y ago
pew pew! If I take that picture in the article as the real thing, how in 7 hells do they keep the optics clean enough on a ship to fire the thing? Or do they need to; does ocean spray on the external-most lens not matter, maybe?
- nickolai 16y ago
  Some sort of water-repellent glass? Or maybe simply a plain old lid. It would be possible to keep the lens closed for most of the time, except for the short period when it is actually active.
GiraffeNecktie 16y ago
Would my simple aluminum foil hat be enough to ... uh ... foil a laser gun?
- Symmetry 16y ago
  Most reflective surfaces are only around 90% reflective at most and cease to be reflective after absorbing a fraction the energy a laser is putting out. You can make much more efficient mirrors, but usually only for a specific frequency.
knowtheory 16y ago
So why do we need this vs just shooting things with bullets? I'm down with the crazy railgun systems they've developed, but this seems like a boondoggle.
- Symmetry 16y ago
  Unfortunately bullets take time to arrive at their target and are effected by gravity. That makes lasers better for shooting small things far away traveling at high speeds.
  - goatforce5 16y ago
    From the video it appeared as though the laser stayed locked on to a certain point on the side of the motor, adjusting for the movement of the ocean. Being a sniper trying to deal with pirates and hostages on a rough sea, for example, must be kinda tricky.
  - knowtheory 16y ago
    Yeah but if you're on the sea, your target is moving all over the place anyway. Lasers, even really powerful ones, have to stay focused on the same point in order to have an effect, yeah? W/ a bullet, you get all the kinetic energy at whatever the point of impact is.
  - wladimir 16y ago
    Lasers aren't a suitable long-range weapon here in the atmosphere, though. The dissipation over distance is very bad. And if your laser is too powerful it'll heat the air it goes through so much that it turns into plasma, making the situation even worse. It might be suitable for shooting fast moving objects such as missiles over a short distance.
- swombat 16y ago
  I guess accuracy is the main benefit. You can aim a laser a lot more accurately than fast-moving chunks of metal... Also, lasers are cool. I'm sure that's a factor :-)
- bradleyland 16y ago
  It depends upon your goal. One 3-second burst from a just about any minigun would clear the deck of a typical pirate vessel, but anyone on board isn't going to return to shore. There are political and ethical considerations to killing pirates on sight. If your goal is to disable the vessel, a laser like this stands a far greater chance of disabling the vessel without killing the inhabitants.

14 points by miraj 16y ago

pew pew! If I take that picture in the article as the real thing, how in 7 hells do they keep the optics clean enough on a ship to fire the thing? Or do they need to; does ocean spray on the external-most lens not matter, maybe?

nickolai 16y ago
Some sort of water-repellent glass? Or maybe simply a plain old lid. It would be possible to keep the lens closed for most of the time, except for the short period when it is actually active.

GiraffeNecktie 16y ago

Would my simple aluminum foil hat be enough to ... uh ... foil a laser gun?

Symmetry 16y ago
Most reflective surfaces are only around 90% reflective at most and cease to be reflective after absorbing a fraction the energy a laser is putting out. You can make much more efficient mirrors, but usually only for a specific frequency.

knowtheory 16y ago

So why do we need this vs just shooting things with bullets? I'm down with the crazy railgun systems they've developed, but this seems like a boondoggle.

Symmetry 16y ago
Unfortunately bullets take time to arrive at their target and are effected by gravity. That makes lasers better for shooting small things far away traveling at high speeds.
- goatforce5 16y ago
  From the video it appeared as though the laser stayed locked on to a certain point on the side of the motor, adjusting for the movement of the ocean. Being a sniper trying to deal with pirates and hostages on a rough sea, for example, must be kinda tricky.
- knowtheory 16y ago
  Yeah but if you're on the sea, your target is moving all over the place anyway. Lasers, even really powerful ones, have to stay focused on the same point in order to have an effect, yeah? W/ a bullet, you get all the kinetic energy at whatever the point of impact is.
- wladimir 16y ago
  Lasers aren't a suitable long-range weapon here in the atmosphere, though. The dissipation over distance is very bad. And if your laser is too powerful it'll heat the air it goes through so much that it turns into plasma, making the situation even worse. It might be suitable for shooting fast moving objects such as missiles over a short distance.
swombat 16y ago
I guess accuracy is the main benefit. You can aim a laser a lot more accurately than fast-moving chunks of metal... Also, lasers are cool. I'm sure that's a factor :-)
bradleyland 16y ago
It depends upon your goal. One 3-second burst from a just about any minigun would clear the deck of a typical pirate vessel, but anyone on board isn't going to return to shore. There are political and ethical considerations to killing pirates on sight. If your goal is to disable the vessel, a laser like this stands a far greater chance of disabling the vessel without killing the inhabitants.