Air-borne laser
Airborne laser - a megawatt-class chemical oxygen

iodine laser (COIL) mounted inside a modified Boeing 747-400F. It is primarily designed as a missile defense system to destroy tactical ballistic missiles (TBMs), while in boost phase (picture). 

Antimatter weapon - a hypothetical device using antimatter as a power source, a propellant, or an explosive for a weapon. Antimatter weapons do not currently exist due to the cost of production and the limited technology available to produce and contain antimatter in sufficient quantities for it to be a useful weapon. The United States Air Force, however, has been interested in military uses — including destructive applications — of antimatter since the Cold War, when it began funding antimatter-related physics research. The primary theoretical advantage of such a weapon is that antimatter and matter collisions convert a greater fraction of the weapon's mass into explosive energy when compared to a fusion reaction, which is only on the order of 0.4% 

Directed energy weapon - emits energy in an aimed direction without the means of a projectile. It transfers energy to a target for a desired effect. 

Plasma weapon -  any theoretical firearm designed to use plasma (high-energy ionized gas) as a weapon.  

Pure fusion weapon - a hypothetical hydrogen bomb design that does not need a fission "primary" explosive to ignite the fusion of deuterium and tritium, two heavy isotopes of hydrogen (see thermonuclear weapon for more information about fission-fusion weapons). Such a weapon would require no fissile material and would therefore be much easier to build in secret than existing weapons. The necessity of separating high-quality fissile material requires a substantial industrial investment, and blocking the sale and transfer of the needed machinery has been the primary mechanism to control nuclear proliferation to date. 

Long-range acoustic device
Sonic weapon - weapons of various types that use sound to injure, incapacitate, or kill an opponent. Some sonic weapons are currently in limited use or in research and development by military and police forces. This weapons is used against demonstrations, e.g. in Georgia, former USSR, picture (Long Range Acoustic Device, LRAD). 

Stealth technology -  a range of techniques used with personnel, aircraftshipssubmarinesmissiles andsatellites to make them less visible (ideally invisible) to radarinfrared,[2] sonar and other detection methods. It corresponds tocamouflage for these parts of the electromagnetic spectrum. 

Vortex ring gun -  an experimental non-lethal weapon for crowd control that uses high-energy vortex rings of gas to knock down people or spray them with marking ink or other chemicals.

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