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67-Kilowatt Laser Unveiled
s31523 writes "Lawrence Livermore National Laboratory in California has announced they have working in the lab a Solid State Heat Capacity Laser that averages 67 kW. It is being developed for the military. The chief scientist Dr. Yamamoto is quoted: 'I know of no other solid state laser that has achieved 67 kW of average output power.' Although many lasers have peaked at higher capacities, getting the average sustained power to remain high is the tricky part. The article says that hitting the 100-kW level, at which point it would become interesting as a battlefield weapon, could be less than a year away."
Cue the frickin' lasers jokes in 3...2...1...
"No freeman shall ever be debarred the use of arms." -- Thomas Jefferson
...will be the "Yamamoto Cannon".
(damn, why couldn't he have been Dr. Yamato)
Let me guess -- the Pentagon now has everything it needs to proceed with the Death Star?
I want five megawatts by mid-May.
The article does not mention that any reflection off whatever the laser is aiming at is many kW as well. A small polished piece of steel would reflect 80% in some random direction, and the beam will go until it reaches something. Only a few milli Watts would be sufficient to damage the eyes of civilian spectators, so a reflection could easily permanently blind everyone in a football stadium of 50000 people.
"Fix it"
Soon, America will wield the power to project an annoying red dot into any room in North Korea or Iran, disturbing and agitating ANY and ALL cats, and, if the resident is so foolish as to investigate... his very eyes may be irritated, and possibly damaged, after prolonged exposure!
I spend most of my time in bed, darling.
The RIAA is terrified that it will be used to burn DVDs at a range of 500 meters. Drive-by piracy is here: hide your children, lock your doors, hire your lawyers!
You need to put the reflective surface on the intercept side of the substrate, glass or otherwise. That way, it is the first thing the laser hits. And of course, you'd better make sure that the efficiency is high enough that the laser doesn't manage to ablate the coating. Maybe coatings aren't that good an idea in the first place. Maybe thick, mirror-polished armor that can direct heat away from the surface really quickly is more what you want. Of course, a little dirt on there, you have a localized heat event, and all of a sudden things aren't as reflective as they should be, and zonk, you have a hole right through the armor.
100 KW for a battlefield laser, eh? Personally, I'm thinking being in front of one of these is a very, very bad idea.
I've fallen off your lawn, and I can't get up.
This is wrong for a number of reasons.
Firstly, I didn't mention spending as a percentage of GDP; I was talking about absolute spending.
Next, comparing spending / GDP with other nations with incredibly low GDPs isn't really giving a clear picture of what's going on. For example, who the hell is Eritrea, the so-called No 1 in military spending in the world? You see, if these countries have a very small GDP, the figures are going to look distorted even if they only buy a couple of grenades.
Next, the US hides massive amounts of its military spending. The figure they used in that CIA table was the official maintenance cost of the US military. This is the amount that would be required just to keep the military at home. But they're never at home! Things like the wars aren't counted by the US, for some reason. These are 'extra' costs. The trillion dollars that Dubya has asked for to cover the next year in Iraq, well that's not counted. The budget of the CIA, with their military coupes against democratically elected governments and such, well that's not counted. And research on weapons such as this laser. That's not counted either. So you see, if all these things were counted, then the US would be at the top of the list in terms of GDP as well. They're already at the top of the list in absolute terms, which is the point I was originally making.
That's because you're either in denial, or you'e completely fooled by the propaganda. It's YOU who needs a tin foil hat
If your mirror is 99% reflective (which would be very, very good -- and it won't stay that way in a dusty dirty battlefield), you'd still be absorbing 1kW of power. Which might be very easy or very hard to dissipate, depending on the beam diameter and how well the targeting system can keep it on the same piece of armor. And, as soon as your armor starts to heat up more than a little, the reflectivity will drop and it will fail.
Everyone always thinks mirrors are an easy answer to laser weapons, but it's not really that simple; sure they're worth considering, but they're not obviously a winning strategy.
A better armor might actually be an ablative -- eg a phenolic or graphite plate that absorbs all the heat at the very surface, and vaporizes into a cloud of gas that then takes the majority of the heating while the armor continues ablating from conducted heat and laser heating that gets through -- meanwhile the targeting system frantically tries to keep the laser on the same spot long enough to punch all the way through, and the tank driver tries to conduct evasive action. Modern ablative technology for rocket engines can take 1kW/cm^2 of heating and last for minutes of service; ablatives derived from such technologies might make very effective armors.
Insightful how? Making mirrors that can withstand 100+kW of energy you can't exactly go down to your hardware store. Insurgents have nowhere near the facilities or technology to create anything close to withstanding 100kW.
Your hair look like poop, Bob! - Wanker.
The fact the SSHCL is able to get 67kW out of a solid state system is very impressive. Most solid state lasers of this sort have been stuck below 10kW and are only about 1% efficient, a 1kW laser needs 1MW of input power 99% of which needs to be shed by a cooling system. Solid state lasers have a definite advantage over chemical ones like the THEL and ABL because their "ammunition" supply is essentially only limited by the amount of electricity they've got available. Chemical lasers consumer reactants in the lasing process and have a finite number of shots before those reactants are exhausted. Those reactants take up a lot of space as well, Isreal's THEL system requires four semi trailers worth of equipment to shoot down small katyusha rockets and mortar rounds.
The Air Force has a real hard on for laser systems. Though it doesn't say specifically in the article it appears this lab was awarded the AFRL's contract to produce a solid state equivalent to the ATL system being developed largely by Boeing. The ATL is a smaller cousin of the ABL weighing in at about 70kW. It's an order of magnitude lower power than the roughly 1MW ABL but is also quite a bit smaller. The ABL requires a 747, the ATL is being developed to be mounted on a C-130 or V-22 Osprey. A solid state ATL would be far more useful for the Air Force than a chemical one. A solid state laser system on an aircraft could be powered by generators hooked to the engines and fired an indefinite number of times in flight.
I'm a loner Dottie, a Rebel.
1) You could deliver your PowerPoint presentation in Paris from your office in San Francisco via videophone and STILL point out the interesting bits to the audience.
2) Later that night you could pick out a cinema in Paris and really piss off the audience by squiggling on the screen.
AT&ROFLMAO
there is little to no physical force behind it; the destructive energy is heat. Things won't explode like they do in Star Wars and other sci fi/fantasy movies and shows.
The satellite-based lasers for Star Wars (Reagan's wet dream, not the Movie) primarily worked by kinetic activity.
A cutting laser doesn't take anywhere near 67kW, but they work fairly slowly (slow enough for an armored target to take countermeasures). Instead, you want to basically vaporize a few nm of the surface, resulting in exactly the sort of explosion you say doesn't happen.
Search Google for "arc flash"... Though a much more mundane effect, it gives the general idea... Basically, if you vaporize copper bus bar by shorting it out, it produces a pretty impressive "explosion" due to the copper suddenly occupying 67,000 (no connection to the laser from the FP, just a coincidence) times its original volume.