Posted by
michael
on from the also-useful-for-making-popcorn dept.
KeyShark writes: "An article on FoxNews describes how front-line troops soon will be protected by battlefield lasers designed to shoot down rockets, artillery shells and even mortars."
Or, just use pen lasers
by
chancycat
·
· Score: 5, Funny
Think about it:
Eash of our troups has a pen laser and two house cats.
1) Release cats between you and the enemy.
2) Direct cats toward enemy trenches with pen light. Watch enemy freak out.
-- Evan - needs to hit preview before submitting
Also under development:
by
Nindalf
·
· Score: 5, Funny
Revolutionary new developments in extremely shiny rockets, artillery shells, and even mortars.
Is it really so difficult?
by
djrogers
·
· Score: 5, Funny
All I asked for were some frickin' laser beams!
-- Think outside the... Hey, where'd the friggin' box go?
Re:This raises some frightening questions
by
Anonymous+DWord
·
· Score: 5, Informative
There's an international treaty that the US has actually signed (wonder of wonders!) against using lasers on people. I tend to doubt it'll be followed in practice though, when "our" forces are involved.
-- "If he thinks he can hide and run from the United States and our allies, he's sorely mistaken." Bush on bin Laden
The granddaddy of all the laser weapons is the Mid-Infrared Advanced Chemical Laser, known as MIRACL, which fills a large building and its surroundings at the test site.
Nice acronym. Now every time I see a picture of someone standing in a beam of divine light from the sky I'm going to get a mental picture of him bursting into flames and melting.
Re:Not too hard.
by
Knobby
·
· Score: 5, Informative
Am i forgetting something here?
Yep.. You're missing density variations and laser induced heating of the local atmosphere. Both of which will degrade the power of your beam, and complicate aiming the device. The Air Forces Airborne laser program attempted to solve these using a pair of low power lasers to sample the atmosphere and track the object. Given the information from the low power lasers, the optics for the primary laser could be corrected to hit the target. I'm not sure they ever got the system to work, but I seem to recall the power of the beam to be roughly equivilent to 30 ocyacetylin (sp?) torches focused on a single point.. There was a lot of speculation in the articles I read, suggesting that the laser power would be attenuated by some staggering amount by the atmosphere, and the chances for success were considered minimal by some of the scientists working on the project..
Hey, any laser powerful enough to damage or divert artillery shells is going to make *thunder* when it fires. It's the same effect as lightning -- superheated air shocks away from the beam, then slams back in when the beam cuts off. That's way more impressive than zzzzt-whoosh-bleem, far as I'm concerned.
-- When all you have is a hammer, everything looks like a skull.
Weapons treaties are there to be ignored by a the parties signing them.
THink of it, you sign a treat to (say) not research biological weapons for offensive purposes, say, like Russia did. Then, you secretly violate the treaty, and now you have weapon the other side doesn't have. Its happened in the past, it'll happen in the future.
Weapons treaties only penalize the honest countries. Dishonest countries won't care. At least we actually do (for the most part) obey our treaties.
There's LOTS of stuff you can burn...
by
Ungrounded+Lightning
·
· Score: 5, Interesting
"These lasers also have a drawback--their energy comes from large tanks of industrial chemicals, which have to be mixed until they glow, like an outsize high-school science project. And they are so bulky that one weapon fills a large aircraft, or a small building. "
Does this jive with the fox news article?
Yes. But it doesn't tell the whole story.
The lasers they're talking about are spinoffs of the Star Wars missile defense system. They had to get a LOT of energy into a beam quickly, to shoot down missiles while still in space, or to bounce off a mirror in space to get them on their way up. One shot, one dead nuke, so cost wasn't much of an object.
Neither was portability: You had either a fortified underground bunker as big as you wanted, or a satellite in zero-G.
So they did something very strong, effective, big, and expensive.
But lasers are EASY. Excluding superradiants (which are easier, if you've got the materials) all you need is a couple of well-alligned mirrors, one of 'em slightly leaky, with an "inverted population amplification light amplification medium" between them.
For "inverted population light amplification medium" read "smoke from a fire".
The medium must have the following characteristics:
It has a state transistion (an "excited state", a "ground state" or less-excited state, and an allowed transition between them) with an energy difference corresponding to a usefully energetic photon.
It must have significantly more of its atoms or molecules in the more-excited state than in the less-excited state. (This is the "inverted population" part.)
It must have ENOUGH of a surplus of more-excited particles to produce a usable amount of power if you extracted the energy difference by de-exciting enough that you're down to 50/50 (or de-exciting them all if there's a further transition that drains the less-excited state).
It must be transparent and reasonably uniform (i.e. non-distorting) at the light frequency corresponding to the state transition.
When you burn darn near ANYTHING the resulting molecules start out excited. If they meet the other criteria you've got a suitable medium for a chemically-pumped laser.
Burn a suitable fuel in a long, thin, rocket flame and run the exhaust at right angles between the pair of mirrors. You'll have a laser beam coming out as long as the flame lasts. Chose the right material and a large fraction of what would have been the heat of combustion ends up in the laser beam.
Now there are some fancy and deadly fuels (fluorine comes to mind) that make an exhaust where the bulk of the energy can be extracted by a single transition. This is nice and efficient. And you don't want to be ANYWHERE NEAR them when in use, due to the toxic nature of the exhaust. So if you're going to be shooting down a nuke from a fort in the desert they're fine.
But there are LOTS of others that are simpler, and might be more suitable for a battlefield.
I expect that eventually we'll see a chemically-pumped laser rifle or pistol, about the same size as a normal rifle or pistol, with an optical cavity where the barrel would be, powered by cartridges of solid fuel that are fed by a mechanism similar to the one that feeds cartridges consisting of case/primer/powder/bullet.
-- Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
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Eash of our troups has a pen laser and two house cats.
1) Release cats between you and the enemy.
2) Direct cats toward enemy trenches with pen light. Watch enemy freak out.
Evan - needs to hit preview before submitting
Revolutionary new developments in extremely shiny rockets, artillery shells, and even mortars.
All I asked for were some frickin' laser beams!
Think outside the... Hey, where'd the friggin' box go?
There's an international treaty that the US has actually signed (wonder of wonders!) against using lasers on people. I tend to doubt it'll be followed in practice though, when "our" forces are involved.
"If he thinks he can hide and run from the United States and our allies, he's sorely mistaken." Bush on bin Laden
Nice acronym. Now every time I see a picture of someone standing in a beam of divine light from the sky I'm going to get a mental picture of him bursting into flames and melting.
Am i forgetting something here?
Yep.. You're missing density variations and laser induced heating of the local atmosphere. Both of which will degrade the power of your beam, and complicate aiming the device. The Air Forces Airborne laser program attempted to solve these using a pair of low power lasers to sample the atmosphere and track the object. Given the information from the low power lasers, the optics for the primary laser could be corrected to hit the target. I'm not sure they ever got the system to work, but I seem to recall the power of the beam to be roughly equivilent to 30 ocyacetylin (sp?) torches focused on a single point.. There was a lot of speculation in the articles I read, suggesting that the laser power would be attenuated by some staggering amount by the atmosphere, and the chances for success were considered minimal by some of the scientists working on the project..
Hey, any laser powerful enough to damage or divert artillery shells is going to make *thunder* when it fires. It's the same effect as lightning -- superheated air shocks away from the beam, then slams back in when the beam cuts off. That's way more impressive than zzzzt-whoosh-bleem, far as I'm concerned.
When all you have is a hammer, everything looks like a skull.
Weapons treaties are there to be ignored by a the parties signing them.
THink of it, you sign a treat to (say) not research biological weapons for offensive purposes, say, like Russia did. Then, you secretly violate the treaty, and now you have weapon the other side doesn't have. Its happened in the past, it'll happen in the future.
Weapons treaties only penalize the honest countries. Dishonest countries won't care. At least we actually do (for the most part) obey our treaties.
Does this jive with the fox news article?
Yes. But it doesn't tell the whole story.
The lasers they're talking about are spinoffs of the Star Wars missile defense system. They had to get a LOT of energy into a beam quickly, to shoot down missiles while still in space, or to bounce off a mirror in space to get them on their way up. One shot, one dead nuke, so cost wasn't much of an object.
Neither was portability: You had either a fortified underground bunker as big as you wanted, or a satellite in zero-G.
So they did something very strong, effective, big, and expensive.
But lasers are EASY. Excluding superradiants (which are easier, if you've got the materials) all you need is a couple of well-alligned mirrors, one of 'em slightly leaky, with an "inverted population amplification light amplification medium" between them.
For "inverted population light amplification medium" read "smoke from a fire".
The medium must have the following characteristics:
It has a state transistion (an "excited state", a "ground state" or less-excited state, and an allowed transition between them) with an energy difference corresponding to a usefully energetic photon.
It must have significantly more of its atoms or molecules in the more-excited state than in the less-excited state. (This is the "inverted population" part.)
It must have ENOUGH of a surplus of more-excited particles to produce a usable amount of power if you extracted the energy difference by de-exciting enough that you're down to 50/50 (or de-exciting them all if there's a further transition that drains the less-excited state).
It must be transparent and reasonably uniform (i.e. non-distorting) at the light frequency corresponding to the state transition.
When you burn darn near ANYTHING the resulting molecules start out excited. If they meet the other criteria you've got a suitable medium for a chemically-pumped laser.
Burn a suitable fuel in a long, thin, rocket flame and run the exhaust at right angles between the pair of mirrors. You'll have a laser beam coming out as long as the flame lasts. Chose the right material and a large fraction of what would have been the heat of combustion ends up in the laser beam.
Now there are some fancy and deadly fuels (fluorine comes to mind) that make an exhaust where the bulk of the energy can be extracted by a single transition. This is nice and efficient. And you don't want to be ANYWHERE NEAR them when in use, due to the toxic nature of the exhaust. So if you're going to be shooting down a nuke from a fort in the desert they're fine.
But there are LOTS of others that are simpler, and might be more suitable for a battlefield.
I expect that eventually we'll see a chemically-pumped laser rifle or pistol, about the same size as a normal rifle or pistol, with an optical cavity where the barrel would be, powered by cartridges of solid fuel that are fed by a mechanism similar to the one that feeds cartridges consisting of case/primer/powder/bullet.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way