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FrozenGate by Avery

Laser Weapons

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planters

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Why are all of these laser weapon demos "focused" on CW lasers?

https://www.youtube.com/watch?v=gVB2b5Hbm04

I can nearly pull this off myself and if I was willing to use a CO2 laser, I could. This undoubtedly multi-million dollar system has to persist on the target for several seconds. I know..." we can supply your war fighters ( another PC term that infuriates me) with a system that is 10 times as powerful". But, if that DJ Phantom were even moderately protected with reflective and ablative coatings then the investment ratios would remain stupid.

https://www.youtube.com/watch?v=gVB2b5Hbm04

Lasers are FAST and they give up much of this speed advantage when they operate as slow cookers. Pulsed lasers create impact and shock waves. This damages without requiring the target mass be turned to vapor. Also, the sensors will be more vulnerable to the brief, high fluence pulse. Furthermore, for targets at close range, the imaging system can operate at the speed of a computer and freeze the target to allow the pulse to crack off a rotor blade while it appears frozen in time.
 





planters said:
Why are all of these laser weapon demos "focused" on CW lasers?

https://www.youtube.com/watch?v=gVB2b5Hbm04

I can nearly pull this off myself and if I was willing to use a CO2 laser, I could. This undoubtedly multi-million dollar system has to persist on the target for several seconds. I know..." we can supply your war fighters ( another PC term that infuriates me) with a system that is 10 times as powerful". But, if that DJ Phantom were even moderately protected with reflective and ablative coatings then the investment ratios would remain stupid.

https://www.youtube.com/watch?v=gVB2b5Hbm04

Lasers are FAST and they give up much of this speed advantage when they operate as slow cookers. Pulsed lasers create impact and shock waves. This damages without requiring the target mass be turned to vapor. Also, the sensors will be more vulnerable to the brief, high fluence pulse. Furthermore, for targets at close range, the imaging system can operate at the speed of a computer and freeze the target to allow the pulse to crack off a rotor blade while it appears frozen in time.
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I'd imagine much of the cost isn't just from the laser but also from the targeting/tracking part of the system. Not to mention I'd imagine it has some sort of range finding and automatic focus that'd add some cost. Plus building it to milspec, and being a government project would mean even more $$$$.

Not sure why they always seem to go with CW either - surely they could build something pulsed but with similar average powers for even more destructive power?
 
It depends on the application really. One place where lasers could replace guns would be the rapidfire cannons on ships. Those rapidfire guns shoot rounds with moderate energy but at a fast rate. To destroy larger targets (such as enemy fighter planes or incoming shells) multiple hits are often required. A CW laser could work with existing targeting systems.

Pulsed lasers are another thing and useful as well, but those systems aren't that widely available. A true single pulse laser would be a chemically pumped one, as was poineered in airborne systems. They do work, but need something vulnerable the size of a 747 jet to be effective.


In warfare everything has its place though, and for some situations lasers could be ideal. One thing i'm thinking off here is defense against improvised rockets such as the isreali armed forces face.

They have built a great system (iron dome) do defend against homebrew palistine missiles, but it is expensive to operate as it requires a small rocket to be fired to intercept each incoming projectile (the interceptor is far for expensive than its taget). Using pulsed lasers could be cost effective there since one good pulse could cause premature detonation of the payload on such simple missiles, rendering them unable to do much damage when they come down. You'd still get hurt if one happened to land on your head, but it'd essentially be a dud and you'd be fine if it landed a meter from your feet onto the ground.
 
War fighters? You mean fighter jets, or soldiers? I've never heard that term.
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Watch for it. For a number of years it has become the PC term to cover all humans involved in the military; all divisions, all ***es all roles. This is why I despise it.

It depends on the application really. One place where lasers could replace guns would be the rapidfire cannons on ships. Those rapidfire guns shoot rounds with moderate energy but at a fast rate. To destroy larger targets (such as enemy fighter planes or incoming shells) multiple hits are often required. A CW laser could work with existing targeting systems.
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I agree here. The energy conversion efficiency for a rail gun should become extremely high if superconducting coils allowed for energy recycling. Chemical energy storage is still very attractive based on density and cost and this is why I think the hyper-velocity projectiles will only be a better alternative for fixed, energy rich platforms such as ships. This is also where free electron lasers become a realistic game changer as well.

The Iron dome is a great system. I think they actually do have some lasers deployed here. I'm not sure about this, but I thought I read about this several years ago.

I believe the use of continuous wave lasers is based on the contractors' unwillingness to fund the research into high power pulsed lasers. They are merely re-purposing commercial, industrial fiber lasers by integrating them into existing targeting systems. Ten thousand watts for three seconds is my guess on the demo above, but 10,000J in one microsecond (1/3 the energy) would put 3 times the energy of a 12 gauge shot gun shell onto the target before the tip of its rotor will have moved 100um. The shock wave would turn the drone into dust and there is no need to persist on the target for so long.

There is some interesting development into cryogenically cooled holmium lasers. The upper state lifetime is on the order of 5msec. This would allow banks of QCW diodes to pump them (once 1.2nm diodes become available). Even flash lamps could dump huge amounts of power into these crystals in such a long period. The resulting, Q switched, nanosecond output at 2.1um could be devastating.
 
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Fiber lasers will be the tool of choice and they will be pulsed because of portable power limitations, ultra caps will be charged from power packs to drive pulsed fiber lasers at least for man portables and small drones, but ship based lasers can run CW and burn cities if they can see them over the horizon and large aircraft mounted lasers will be able to provide the power and cooling infrastructure, but man portables likely will be pulsed.

Mthel, Firestrike and Hellads are old news now, but they show the concept and progression.

Also focusing on a target through this variable lens called humidity laden air is an issue, like you say the targeting is the trick, phase shifting focusing is faster than mechanical means.

Also for MTHEL and ship based a big wide output aperture can be focused to a dime sized point, but man portables are limited in starting diameter and thus range.

And as the Chinese announce their man portable blinding lasers we will equip our troops with enhanced headwear, like a fighter jet helmet with an array of CCD and heat vision sensors, the human eye will not be exposed to the open air on the future battlefield and small drones will become a big force multiplier, thus the countermeasure will have to be equally robust.

The limitations of human reaction time are already exceeded and the amount of G force a man can take in an aircraft dogfight will be .... is already surpassed by robotic jet drones.

However when all the fancy toys and countermeasures are used up the redundancy of the foot soldier will come back into play, unless an industrial giant has enough preparedness to negate depletion of the new force multipliers.

HERF and EMP weapons may penetrate the best faraday type shielding and things may resort to the foot soldier redundancy.

So all our eggs can not be in one basket, but as China builds bigger baskets we are downsizing and relying on high tech to do more than it will be able, actually the coming war will be financial and nano tech as well as germ tech may prevent a physical confrontation except for small pissing matches, the future and present battle is financial and mental, too bad we don't have any chess players who can think all that far ahead, we are actually working against ourselves and selling out our own nation for personal gain, our leadership will have us all bought and sold and our eventual resistance may be futile, we are letting it happen.

But what about one world, with everyone working together....yes and there will be controllers and worker bees, who do you think will decide who does what and who is of any value, or even needed.....but don't worry about that, we have a While house to light up in rainbow colors and me must decide what bathroom to use....do you not see us being destroyed from within?

Ok the main topic, Yes, repackaging of industrial tech for a fast profit, more short sighted self destruction.
Maybe the Chinese will sell us some good weapons so we can play democracy builder in the sandbox, speaking of the sandbox I saw a Tesla S the other day with the AWD and Ludacris upgrade, that thing leapt out and blasted down the road like a silent dragster.

When the petro dollar is dead and cold fusion is up and running what will we control?

How will we pay our bills?

Multi generational housing and public transit anyone?

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The Drone burning video, a highly directional HERF gun would be more effective and safer for bystanders, also it's what will work, the brushless motor controllers and the detonation of the payload could be HERF initiated.
 
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so.... how long until LPF has a 'Laser Weapon systems' section for future DIY projects?
 
Hopefully never, yes I know your joking.

We can revel in the technology and pontificate on how it could theoretically be improved, such as X-ray lasers that do exist and one was under construction by some industry technical who wanted " allegedly " to commit a crime with one.

But why burn through a brick wall when you can fry the fleshy combatant behind it, right through it.

The following link is for academic study and discussion only, no law is to be broken in any way nor any conspiracy to commit a crime committed, this is for academic discussion only.

FBI foils assassination plot against President Obama ? TV - News - World - The Voice of Russia: News, Breaking news, Politics, Economics, Business, Russia, International current events, Expert opinion, podcasts, Video


http://news.discovery.com/tech/xray-laser-most-powerful-ever-120125.htm
 
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What about hand-held laser weapons? Reality some day or just star trek lore. Nothing that powerful right now, unless perhaps you use an array of diodes and strap a marine deep cycle lead acid battery to your back. Well, it might look intimidating if someone took something like a Hurst shifter, and mounted it on one of those 5-7 watt flashlight lasers. It would be wicked-cool if it had a working trigger!

Hurst 1536200 Universal Pistol Grip Handle with Switch | eBay
 
Man-mounted lasers strong enough to destroy incoming shells and such are not that far away.

For now lasers seem to be mostly defensive weapons - they are good for shooting down incoming ammo, rockets and such. As offensive weapons they are not that good yet, and also easily defended against: if the enemy is shooting lasers are you, bring retroreflectors :)
 
X ray lasers are a division of free electron lasers that are proposed for ship mounted defenses.

They operate pretty simply.

The electron beam is accelerated to somewhere above 1x10^8 eV. The higher the better, but there are trade offs such as current. The higher the current, the better as well. The beam then passes into a wiggler or an undulator depending on the plane and the rapid and repeated acceleration of the electrons through this long series of alternating magnetic fields causes the electrons to produce syncrotron radiation tangential to the acceleration vector. Because all these magnets are aligned, the syncrotron radiation is aligned as well. The product of the acceleration magnitude and the beam voltage determines the wavelength. Because these electrons are relativistic the wavelength is blue shifted and this blue shift can be very large, moving the output from the infrared through the visible and into the x ray region. If mirrors are placed to create a laser cavity out of this wiggler region then the feedback of the light generated here will interact with the electrons causing them to bunch in phase with the light, greatly increasing their interaction with the wiggler field and generating coherent laser light pulses of incredible power and short duration.

The advantage of an X-ray laser is the deep penetration will heat a larger mass of material, producing more momentum. When you hit a piece of metal with a beam that is absorbed in the first micron, the plasma becomes very hot and rockets away at supersonic speed, but there is very little of it. 1/2MV^2 means that if you can just vaporize a larger mass of material then the same energy will produce a much larger "kick".
 
The principle of operation is not that complex, but practically building one has its problems. Apart from dealing with voltages in the order of a gigavolt you also need to maintain a vacuum in a relatively large volume.

Perhaps we'll see these lasers mounted on warships, but i doubt they will get much more 'portable' than that anytime soon.
 
The principle of operation is not that complex,
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That isn't complex, but that is how they work. A synchrotron light source is even simpler and can be very intense, yet to be a laser there has to be feedback from the light to the gain medium and in this case that is the electron packets. It is true that if the gain is sufficiently high, as in a superradient laser, you can produce lasing without the cavity optics.

Another problem is that the electrons that exit the laser contain a lot of energy and recycling this beam back into the accelerator is challenging.

Perhaps we'll see these lasers mounted on warships, but i doubt they will get much more 'portable' than that anytime soon.
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Agreed.
 
Hand held backscatter Xray technology is in use and the vehicle mounted units can see through a foot of steel, granted the receptors are very sensitive but the directed emission of x-ray radiation is part of this equipment, it's already in use, more power and a tighter directed beam has no doubt been pursued and achieved, as always the limitations will be man portable power sources.

 
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And it's a totally different field of application.

X-ray scanning equipment allows you to find things left unshielded quite easily, and good for security checkpoints and all that.

This has nothing to do with using it as an actual weapon though. Lasers, x-ray or otherwise, can be used to defend against incoming missiles and such. This application is seeing practical use today.

A step beyond that would be using them for offense, as in death-rays that set enemy tanks on fire and all that stuff. This capability is still not really there for man-carried systems, though it can be implemented on ships and to some degree even on planes right now.

It will take some time for laser weapons to become a common sight on the battlefield, but i think we will see them at some point. Even if intended as defensive weapons they could be used in offensive roles as well - just like the rapidfire cannons on navy ships.
 
Actually you wont see or hear them, if you survive you may have seem what they did, this technology is on the fast track and already in use as ship, tank, plane and vehicle mounted, man portable is waiting for an advance in portable power sources although the Chinese have blinding rifles for disabling "sensors".


PY132A-laser1.png


Looks like it has a zoom lens, I wonder how many watts it puts out, maybe pulsed, unfocused at short range they could blind a lot of "sensors"
 
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