This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these template messages)(Learn how and when to remove this template message)
A directed-energy weapon (DEW) emits highly focused energy, transferring that energy to a target to damage it.
The Pentagon, DARPA, the Air Force Research Laboratory, and the Naval Research Laboratory are researching technologies like directed-energy weapon and railguns to counter maturing threats posed by fast missiles such as ballistic missiles, hypersonic cruise missiles, and hypersonic glide vehicles. These systems of missile defense are expected to come online in the mid to late-2020s.
- 1 Operational advantages
- 2 Types
- 3 Laser weapons
- 4 Problems with laser weapons
- 5 Particle-beam weapons
- 6 Sonic weapons
- 7 History
- 8 Future
- 9 Non-lethal weapons
- 10 See also
- 11 Notes
- 12 References
- 13 External links
Directed energy weapons could have several main advantages over conventional weaponry:
- Direct energy weapons can be used discreetly as radiation above and below the visible spectrum is invisible and does not generate sound.
- Light is only very slightly altered by gravity, giving it an almost perfectly flat trajectory. It is also practically immune (in anything resembling normal planetary conditions) to both windage and Coriolis force. This makes aim much more precise and extends range to line-of-sight, limited only by beam diffraction and spread (which dilute the power and weaken the effect), and absorption or scattering by intervening atmospheric contents.
- They can have much greater speed and range than conventional weapons therefore are suitable for use in space warfare.
Although some devices are labelled as microwave weapons, the microwave range is commonly defined as being between 300 MHz and 300 GHz which is within the RF range. Some examples of weapons which have been publicized by the military are as follows:
- Active Denial System is a millimeter wave source that heats the water in the target's skin and thus causes incapacitating pain. It is being used by the U.S. Air Force Research Laboratory and Raytheon for riot-control duty. Though intended to cause severe pain while leaving no lasting damage, concern has been voiced as to whether the system could cause irreversible damage to the eyes. There has yet to be testing for long-term side effects of exposure to the microwave beam. It can also destroy unshielded electronics: see TEMPEST (research into unintended electronic release of information). The device comes in various sizes including attached to a humvee.
- Vigilant Eagle is an airport defense system that directs high-frequency microwaves towards any projectile that is fired at an aircraft. The system consists of a missile-detecting and tracking subsystem (MDT), a command and control system, and a scanning array. The MDT is a fixed grid of passive infrared (IR) cameras. The command and control system determines the missile launch point. The scanning array projects microwaves that disrupt the surface-to-air missile's guidance system, deflecting it from the aircraft.
- Bofors HPM Blackout is a high-powered microwave weapon system which is stated to be able to destroy at distance a wide variety of commercial off-the-shelf (COTS) electronic equipment. It is stated to be not lethal to humans.
- The effective radiated power (ERP) of the EL/M-2080 Green Pine radar makes it a possible candidate for conversion into a directed-energy weapon, by focusing pulses of radar energy on target missiles. The energy spikes are tailored to enter missiles through antennas or sensor apertures where they can fool guidance systems, scramble computer memories or even burn out sensitive electronic components.
- AESA radars mounted on fighter aircraft have been slated as directed energy weapons against missiles, however, a senior US Air Force officer noted: "they aren't particularly suited to create weapons effects on missiles because of limited antenna size, power and field of view". Potentially lethal effects are produced only inside 100 metres range, and disruptive effects at distances on the order of one kilometre. Moreover, cheap countermeasures can be applied to existing missiles.
An electrolaser first ionizes its target path, and then sends a powerful electric current down the conducting track of ionized plasma, somewhat like lightning. It functions as a giant, high-energy, long-distance version of the Taser or stun gun.
Pulsed energy projectile
Pulsed Energy Projectile or PEP systems emit an infrared laser pulse which creates rapidly expanding plasma at the target. The resulting sound, shock and electromagnetic waves stun the target and cause pain and temporary paralysis. The weapon is under development and is intended as a non-lethal weapon in crowd control though it can also be used as a lethal weapon.
A Dazzler is a directed-energy weapon intended to temporarily blind or disorient its target with intense directed radiation. Targets can include sensors or human vision. Dazzlers emit infrared or invisible light against various electronic sensors, and visible light against humans, when they are intended to cause no long-term damage to eyes. The emitters are usually lasers, making what is termed a laser dazzler. Most of the contemporary systems are man-portable, and operate in either the red (a laser diode) or green (a diode-pumped solid-state laser, DPSS) areas of the electromagnetic spectrum.
The personnel halting and stimulation response rifle (PHASR) is a prototype non-lethal laser dazzler developed by the Air Force Research Laboratory's Directed Energy Directorate, U.S. Department of Defense. Its purpose is to temporarily disorient and blind a target. Blinding laser weapons have been tested in the past, but were banned under the 1995 United Nations Protocol on Blinding Laser Weapons, which the United States acceded to on 21 January 2009. The PHASR rifle, a low-intensity laser, is not prohibited under this regulation, as the blinding effect is intended to be temporary. It also uses a two-wavelength laser. The PHASR was tested at Kirtland Air Force Base, part of the Air Force Research Laboratory Directed Energy Directorate in New Mexico.
- PY132A is a Chinese anti-drone dazzler.
- Soviet laser pistol was a prototype weapon designed for cosmonauts.
Laser weapon examples
- Project Excalibur was a United States government nuclear weapons research program to develop a nuclear pumped x-ray laser as a directed energy weapon for ballistic missile defence.
- In 1984 the Soviet Strategic Missile Troops military academy developed the first handheld laser weapon, intended for use by cosmonauts in outer space.
- 1K17 Szhatie- Experimental Soviet self-propelled laser weapon.
- In 1987 a Soviet laser-armed orbital weapon system, the 17F19DM Polyus/Skif-DM, failed during deployment.
- In 1991 scientists at the US Army Missile Command developed and field tested a ruggedized tunable laser emitting in yellow-orange-red part of the spectrum.
- Made by Northrop Grumman:
- On March 18, 2009 Northrop Grumman announced that its engineers in Redondo Beach had successfully built and tested an electric laser capable of producing a 100-kilowatt ray of light, powerful enough to destroy cruise missiles, artillery, rockets and mortar rounds. An electric laser is theoretically capable, according to Brian Strickland, manager for the United States Army's Joint High Power Solid State Laser program, of being mounted in an aircraft, ship, or vehicle because it requires much less space for its supporting equipment than a chemical laser.
- On April 6, 2011, the U.S. Navy successfully tested a laser gun, manufactured by Northrop Grumman, that was mounted on the former USS Paul Foster, which is currently used as the navy's test ship. When engaged during the test that occurred off the coast of Central California in the Pacific Ocean test range, the laser gun was documented as having "a destructive effect on a high-speed cruising target", said Chief of Naval Research Admiral Nevin Carr. While classified, the proposed range of the laser gun is measured in miles, not yards.
- Northrop Grumman has announced the availability of a high-energy solid-state laser weapon system that they call FIRESTRIKE, introduced on 13 November 2008. The system is modular, using 15 kW modules that can be combined to provide various levels of power.
- Skyguard (area defense system)
- Boeing YAL-1
- Precision Airborne Standoff Directed Energy Weapon
- On 19 July 2010 an anti-aircraft laser described as the Laser Close-In Weapon System was unveiled at the Farnborough Airshow.
- The ZEUS-HLONS (HMMWV Laser Ordnance Neutralization System) is the first laser and the first energy weapon of any type to be used on a battlefield. It is used for neutralizing mines and unexploded ordnance.
- High Energy Liquid Laser Area Defense System (HELLADS)
- The Mid-Infrared Advanced Chemical Laser (MIRACL) is an experimental U.S. Navy deuterium fluoride laser and was tested against an Air Force satellite in 1997.
- In 2011, the U.S. Navy began to test the Maritime Laser Demonstrator (MLD), a laser for use aboard its warships.
- In 2013 the U.S. began field testing a directed-energy weapon it calls the Laser Weapon System.
- Personnel Halting and Stimulation Response, or PHaSR, is a non-lethal hand-held weapon developed by the United States Air Force Its purpose is to "dazzle" or stun a target. It was developed by Air Force's Directed Energy Directorate.
- Tactical High Energy Laser (THEL) is a weaponized deuterium fluoride laser developed in a joint research project by Israel and the U.S. It is designed to shoot down aircraft and missiles. See also National missile defense.
- Soviet/Russian Beriev A-60: a CO2 gas laser mounted on an Ilyushin Il-76MD transport.
- The U.S. Air Force's Airborne Laser, or Advanced Tactical Laser, was a plan to mount a CO2 gas laser or COIL chemical laser on a modified Boeing 747 to shoot down missiles.
- High Energy Laser-Mobile Demonstrator (HEL-MD) is a Boeing designed laser system mounted on a Heavy Expanded Mobility Tactical Truck (HEMTT). Its current power level is 10 kW, which will be boosted to 50 kW, and expected to eventually be upgraded to 100 kW. Targets that can be engaged are mortar rounds, artillery shells and rockets, unmanned aerial vehicles, and cruise missiles.
- Lockheed Martin is developing a 60 kW fiber laser to mount on the HEMTT that maintains beam quality at high power outputs while using less electricity than solid-state lasers.
- Free-electron laser (FEL) technology is being evaluated by the US Navy as a candidate for an antiaircraft and anti-missile directed-energy weapon. The Thomas Jefferson National Accelerator Facility's FEL has demonstrated over 14 kW power output. Compact multi-megawatt class FEL weapons are undergoing research. On June 9, 2009 the Office of Naval Research announced it had awarded Raytheon a contract to develop a 100 kW experimental FEL. On March 18, 2010 Boeing Directed Energy Systems announced the completion of an initial design for U.S. Naval use. A prototype FEL system was demonstrated, with a full-power prototype scheduled by 2018.
- Portable Efficient Laser Testbed (PELT)
- Laser AirCraft CounterMeasures (ACCM)
- Mobile Expeditionary High-Energy Laser (MEHEL) 2.0
- Area Defense Anti-Munitions (ADAM)
- Advanced Test High Energy Asset (ATHENA)
- Self-Protect High-Energy Laser Demonstrator (SHiELD)
- Silent Hunter (laser weapon) is a Chinese fibre optic laser air-defence system
- See also Electrolaser#Examples of electrolasers.
Problems with laser weapons
Laser beams begin to cause plasma breakdown in the atmosphere at energy densities of around one megajoule per cubic centimetre. This effect, called "blooming," causes the laser to defocus and disperse energy into the surrounding air. Blooming can be more severe if there is fog, smoke, or dust in the air.
Techniques that may reduce these effects include:
- Spreading the beam across a large, curved mirror that focuses the power on the target, to keep energy density en route too low for blooming to happen. This requires a large, very precise, fragile mirror, mounted somewhat like a searchlight, requiring bulky machinery to slew the mirror to aim the laser.
- Using a phased array. For typical laser wavelengths, this method would require billions of micrometre-size antennae. There is currently no known way to implement these, though carbon nanotubes have been proposed. Phased arrays could theoretically also perform phase-conjugate amplification (see below). Phased arrays do not require mirrors or lenses, and can be made flat and thus do not require a turret-like system (as in "spread beam") to be aimed, though range will suffer if the target is at extreme angles to the surface of the phased array.
- Using a phase-conjugate laser system. This method employs a "finder" or "guide" laser illuminating the target. Any mirror-like ("specular") points on the target reflect light that is sensed by the weapon's primary amplifier. The weapon then amplifies inverted waves, in a positive feedback loop, destroying the target, with shockwaves as the specular regions evaporate. This avoids blooming because the waves from the target pass through the blooming, and therefore show the most conductive optical path; this automatically corrects for the distortions caused by blooming. Experimental systems using this method usually use special chemicals to form a "phase-conjugate mirror". In most systems, the mirror overheats dramatically at weapon-useful power levels.
- Using a very short pulse that finishes before blooming interferes.
- Focusing multiple lasers of relatively low power on a single target.
The Chinese People's Liberation Army has invested in the development of coatings that can deflect beams fired by U.S. military lasers. Lasers are composed of light that can be deflected, reflected, or absorbed by manipulating physical and chemical properties of materials. Artificial coatings can counter certain specific types of lasers, but if a different type was used than the coating was designed to handle it would be able to burn through it. The coatings are made of several different substances, including low-cost metals, rare earths, carbon fiber, silver, and diamonds that have been processed to fine sheens and tailored against specific laser weapon systems. China is developing anti-laser defenses because protection against them is considered far cheaper than creating competing laser weapons themselves. Apart from creating countermeasures, China have created a laser weapon called the Silent Hunter that can burn through 5mm of steel at 1000m.
The use of x-ray lasers as a defense was created in the 1980s. The idea for this space based laser was to create a curtain in the case that a nuclear attack took place. The curtain was formed by an initial nuclear blast and create a barrier for the incoming missiles. The Cabra event was the first test of this technology. The test failed because the sensor used to detect if the curtain had formed was destroyed in the explosion of the nuclear weapon. This failed test was later used to argue why no more money should be used for the Strategic Defense Initiative.
Particle-beam weapons can use charged or neutral particles, and can be either endoatmospheric or exoatmospheric. Particle beams as beam weapons are theoretically possible, but practical weapons have not been demonstrated yet. Certain types of particle beams have the advantage of being self-focusing in the atmosphere.
Blooming is also a problem in particle-beam weapons. Energy that would otherwise be focused on the target spreads out; the beam becomes less effective:
- Thermal blooming occurs in both charged and neutral particle beams, and occurs when particles bump into one another under the effects of thermal vibration, or bump into air molecules.
- Electrical blooming occurs only in charged particle beams, as ions of like charge repel one another.
The MARAUDER (Magnetically Accelerated Ring to Achieve Ultra-high Directed-Energy and Radiation) used the Shiva Star project (a high energy capacitor bank which provided the means to test weapons and other devices requiring brief and extremely large amounts of energy) to accelerate a toroid of plasma at a significant percentage of the speed of light.
Cavitation, which affects gas nuclei in human tissue, and heating can result from exposure to ultrasound and can damage tissue and organs. Studies have found that exposure to high intensity ultrasound at frequencies from 700 kHz to 3.6 MHz can cause lung and intestinal damage in mice. Heart rate patterns following vibroacoustic stimulation have resulted in serious arterial flutter and bradycardia. Researchers have concluded that generating pain through the auditory system using high intensity sound risked permanent hearing damage.
A multi-organization research program involved high intensity audible sound experiments on human subjects. Extra-aural (unrelated to hearing) bioeffects on various internal organs and the central nervous system included auditory shifts, vibrotactile sensitivity change, muscle contraction, cardiovascular function change, central nervous system effects, vestibular (inner ear) effects, and chest wall/lung tissue effects. Researchers found that low frequency sonar exposure could result in significant cavitations, hypothermia, and tissue shearing. Follow-on experiments were not recommended.
Tests performed on mice show the threshold for both lung and liver damage occurs at about 184 dB. Damage increases rapidly as intensity is increased. Noise-induced neurological disturbances in humans exposed to continuous low frequency tones for durations longer than 15 minutes involved development of immediate and long-term problems affecting brain tissue. The symptoms resembled those of individuals who had suffered minor head injuries. One theory for a causal mechanism is that the prolonged sound exposure resulted in enough mechanical strain to brain tissue to induce an encephalopathy.
Long Range Acoustic Device (LRAD)
The Long Range Acoustic Device (LRAD) is an acoustic hailing device developed by LRAD Corporation to send messages and warning tones over longer distances or at higher volume than normal loudspeakers. LRAD systems are used for long range communications in a variety of applications including as a means of non-lethal, non-kinetic crowd control. Though they have been called "sonic weapons", LRADs are not inherently for military use.
According to the manufacturer's specifications, the systems weigh from 15 to 320 pounds (6.8 to 145.1 kg) and can emit sound in a 30°- 60° beam at 2.5 kHz.
Mirrors of Archimedes
According to a legend, Archimedes created a mirror with an adjustable focal length (or more likely, a series of mirrors focused on a common point) to focus sunlight on ships of the Roman fleet as they invaded Syracuse, setting them on fire. Historians point out that the earliest accounts of the battle did not mention a "burning mirror", but merely stated that Archimedes's ingenuity combined with a way to hurl fire were relevant to the victory. Some attempts to replicate this feat have had some success; in particular, an experiment by students at MIT showed that a mirror-based weapon was at least possible, if not necessarily practical.
In 1935, the British Air Ministry asked Robert Watson-Watt of the Radio Research Station whether a "death ray" was possible. He and colleague Arnold Wilkins quickly concluded that it was not feasible, but as a consequence suggested using radio for the detection of aircraft and this started the development of radar in Britain.
Engine-stopping rays are a variant that occurs in fiction and myth. Such stories were circulating in Britain around 1938. The tales varied but in general terms told of tourists whose car engine suddenly died and were then approached by a German soldier who told them that they had to wait. The soldier returned a short time later to say that the engine would now work and the tourists drove off. A possible origin of some of these stories arises from the testing of the television transmitter in Feldberg, Germany. Because electrical noise from car engines would interfere with field strength measurements, sentries would stop all traffic in the vicinity for the twenty minutes or so needed for a test. A distorted retelling of the events might give rise to the idea that a transmission killed the engine.
Modern automobile engines are not mechanically but electronically controlled. Disabling the electronics can indeed stop the engine. This has been implemented in OnStar, which has a remote control feature, but this is not a weapon. It is an add-on to the electronics of the car. Because a car is operating on a closed system, it would be impossible to use an electronic means of disengaging an engine, short of electrocuting it via laser or pulse weaponry. See also electromagnetic pulse (EMP), which is known for its engine-stopping effect, but is an undirected-energy weapon.
In 2015, Lockheed Martin reported a demonstration of the ATHENA Laser Weapons System that disabled the engine of a truck from a distance of one mile.
Nikola Tesla (1856–1943), a noted inventor, scientist and electrical engineer, developed early high frequency technologies. Tesla worked on plans for a directed-energy weapon from the early 1900s until his death. In 1937, Tesla composed a treatise entitled The Art of Projecting Concentrated Non-dispersive Energy through the Natural Media concerning charged particle beams.
German World War II experimental weapons
During the early 1940s Axis engineers developed a sonic cannon that could cause fatal vibrations in its target body. A methane gas combustion chamber leading to two parabolic dishes pulse-detonated at roughly 44 Hz. This sound, magnified by the dish reflectors, caused vertigo and nausea at 200–400 metres (220–440 yd) by vibrating the middle ear bones and shaking the cochlear fluid within the inner ear. At distances of 50–200 metres (160–660 ft), the sound waves could act on organ tissues and fluids by repeatedly compressing and releasing compressive resistant organs such as the kidneys, spleen, and liver. (It had little detectable effect on malleable organs such as the heart, stomach and intestines.) Lung tissue was affected at only the closest ranges as atmospheric air is highly compressible and only the blood rich alveoli resist compression. In practice, the weapon system was highly vulnerable to enemy fire. Rifle, bazooka and mortar rounds easily deformed the parabolic reflectors, rendering the wave amplification ineffective.
Among the directed-energy weapons the Nazis investigated were X-ray beam weapons developed under Heinz Schmellenmeier, Richard Gans and Fritz Houtermans. They built an electron accelerator called Rheotron (invented by Max Steenbeck at Siemens-Schuckert in the 1930s, these were later called Betatrons by the Americans) to generate hard X-ray synchrotron beams for the Reichsluftfahrtministerium (RLM). The intent was to pre-ionize ignition in aircraft engines and hence serve as anti-aircraft DEW and bring planes down into the reach of the FLAK. The Rheotron was captured by the Americans in Burggrub on April 14, 1945.
Strategic Defense Initiative
In the 1980s, U.S. President Ronald Reagan proposed the Strategic Defense Initiative (SDI) program, which was nicknamed Star Wars. It suggested that lasers, perhaps space-based X-ray lasers, could destroy ICBMs in flight. Panel discussions on the role of high-power lasers in SDI took place at various laser conferences, during the 1980s, with the participation of noted physicists including Edward Teller.
Though the strategic missile defense concept has continued to the present under the Missile Defense Agency, most of the directed-energy weapon concepts were shelved. However, Boeing has been somewhat successful with the Boeing YAL-1 and Boeing NC-135, the first of which destroyed two missiles in February 2010. Funding has been cut to both of the programs.
During the Iraq War, electromagnetic weapons, including high power microwaves, were used by the U.S. military to disrupt and destroy Iraqi electronic systems and may have been used for crowd control. Types and magnitudes of exposure to electromagnetic fields are unknown.
Alleged tracking of Space Shuttle Challenger
The Soviet Union invested some effort in the development of ruby and carbon dioxide lasers as anti-ballistic missile systems, and later as a tracking and anti-satellite system. There are reports that the Terra-3 complex at Sary Shagan was used on several occasions to temporarily "blind" US spy satellites in the IR range.
It has been claimed (and proven false) that the USSR made use of the lasers at the Terra-3 site to target the Space Shuttle Challenger in 1984. At the time, the Soviet Union were concerned that the shuttle was being used as a reconnaissance platform. On 10 October 1984 (STS-41-G), the Terra-3 tracking laser was allegedly aimed at Challenger as it passed over the facility. Early reports claimed that this was responsible for causing "malfunctions on the space shuttle and distress to the crew", and that the United States filed a diplomatic protest about the incident. However, this story is comprehensively denied by the crew members of STS-41-G and knowledgeable members of the US intelligence community.
The TECOM Technology Symposium in 1997 concluded on non-lethal weapons, "determining the target effects on personnel is the greatest challenge to the testing community", primarily because "the potential of injury and death severely limits human tests".
Also, "directed energy weapons that target the central nervous system and cause neurophysiological disorders may violate the Certain Conventional Weapons Convention of 1980. Weapons that go beyond non-lethal intentions and cause "superfluous injury or unnecessary suffering" may also violate the Protocol I to the Geneva Conventions of 1977."
Some common bio-effects of non-lethal electromagnetic weapons include:
Interference with breathing poses the most significant, potentially lethal results.
- Active Denial System (ADS), a non-lethal directed-energy weapon developed by the U.S. military, for area denial, perimeter security and crowd control
- Electronic warfare
- Electromagnetic pulse
- Laser applications
- List of laser articles
- List of plasma (physics) applications articles
- "Daily Telegraph, 12th September 2013", Golden Eye-style energy beam is developed by Nato scientists, Oct. 08, 2013
- "Milsat Magazine, Satnews Daily, June 24th 2009", U.S. Navy Laser Versus UAVs... Laser Wins..., Oct. 08, 2013
- Thaad-ER In Search Of A Mission - Aviationweek.com, 20 January 2015
- "Defence IQ talks to Dr Palíšek about Directed Energy Weapon systems", Defence iQ', Nov. 20, 2012
- Spectrum Tutorial, University of Wisconsin Electromagnetic Spectrum Tutorial, accessed 22/06/2013
- RF vs Microwave Freq range, Microwaves and radio waves
- "The Pentagon's Ray Gun". CBS News. 2008-06-01. Retrieved 2009-03-30.
- Raytheon focuses on non-lethal weapons, Andrew Johnson, (The Arizona Republic, 09-17-2009)
- [dead link]
-  Archived August 25, 2010, at the Wayback Machine.
- Magnus Karlsson (2009). "Bofors HPM Blackout". Artilleri-Tidskrift (2-2009): s. s 12-15. Retrieved 2010-01-04.
- Google search
- Fulghum, David A. (2005-12-17). "Israel tests improved Arrow interceptor". Aviation Week & Space Technology. Retrieved 2009-08-19.
- David A. Fulghum & Douglas Barrie (2005-09-06). "Radar Becomes A Weapon". Aviation Week & Space Technology. Retrieved 2014-05-16.
- Colonel of Aviation Grigoriy "Grisha" Medved (retd) (2008-04-13). "Grisha's Radar fry-off". Air Power Australia. Retrieved 2014-05-16.
- Mark Harris (27 May 2009). "US cops and military to get laser guns". Techradar.com. Retrieved 28 July 2010.
- Chris Matyszczyk (23 July 2010). "Police to experiment with blinding 'Dazer Laser'?". CNET.com. Retrieved 28 July 2010.
- Eva D. Blaylock (Air Force Research Laboratory Directed Energy Directorate Public Affairs). New technology 'dazzles' aggressors, The Official Website of the U.S. Air Force, Posted November 2, 2005
- "United Nations Office at Geneva". www.unog.ch. Retrieved 15 January 2009.
- PERSONNEL HALTING and STIMULATION RESPONSE (PHaSR) Fact Sheet, Air Force Research Laboratory, Office of Public Affairs, April 2006; Archived
- Waldman, Harry (1988). The Dictionary of SDI. New York: Rowman & Littlefield. pp. 58, 157–158. ISBN 0842022953.
- F. J. Duarte, W. E. Davenport, J. J. Ehrlich, and T. S. Taylor, Ruggedized narrow-linewidth dispersive dye laser oscillator, Opt. Commun. 84, 310-316 (1991).
- Joint High Power Solid-State Laser fact sheet, Northrop Grumman Corporation, April 22, 2008 
- Pae, Peter, "Northrop Advance Brings Era Of The Laser Gun Closer", Los Angeles Times, March 19, 2009., p. B2.
- Northrop Grumman (2010-04-07). "Navy Shows Off Powerful New Laser Weapon". Foxnews.com. Retrieved 2011-09-25.
- Emery, Daniel (2010-07-19). "BBC News - Anti-aircraft laser unveiled at Farnborough Airshow". Bbc.co.uk. Retrieved 2011-09-25.
- MLD Test Moves Navy a Step Closer to Lasers for Ship Self-Defense, official press release, 4/8/11.
- Navy tests laser gun by zapping motorboat off California coast, LA Times, 4/11/11.
- Luis Martinez (9 Apr 2013). "Navy's New Laser Weapon Blasts Bad Guys From Air, Sea". ABC. Retrieved 9 April 2013.
- Air Force Link News story on the PHaSR handheld rifle-style weapon. 2 November 2005.
- Wired News article "Weapons Freeze, Microwave Enemies" (and copied in at least 661 other web pages including this link) Archived June 14, 2006, at the Wayback Machine.
- Boeing YAL-1 Airborne Laser (ABL) | Photos and Pictures
- U.S. Army's vehicle-mounted High Energy Laser Mobile Demonstrator shoots down UAVs, mortar rounds - Laserfocusworld.com, 13 December 2013
- Lockheed Martin Wins Contract To Develop Weapons Grade Fiber Laser For U.S. Army Field Test - Providencejournal.com, 24 April 2014
- "Jefferson Lab FEL". Retrieved 2009-06-08.
- "Airborne megawatt class free-electron laser for defense and security". Retrieved 2007-12-21.
- "Raytheon Awarded Contract for Office of Naval Research's Free Electron Laser Program". Retrieved 2009-06-12.
- "Boeing Completes Preliminary Design of Free Electron Laser Weapon System". Retrieved 2010-03-29.
- "Breakthrough Laser Could Revolutionize Navy's Weaponry". Fox News. 2011-01-20. Retrieved 2011-01-22.
- "The Leading Mil Net Site on the Net". milnet.com. Retrieved 2012-06-12.
- Atomic Rocket: Space War: Weapons
- US lasers? PLA preparing to raise its deflector shields - SCMP.com, 10 March 2014
- Nilsen, Joseph (1994). Legacy (PDF).
- "Energy Citations Database (ECD) - - Document #7369133". Osti.gov. doi:10.1063/1.860681. Retrieved 2012-06-12.
- Naval Submarine Medical Research Laboratory (Groton, Connecticut), Navy Experimental Diving Unit (Panama City, Florida), SCC San Diego, Navy Medical Research and Development Command (Bethesda, Maryland), Underwater Sound Reference Detachment of Naval Undersea Warfare Center (Orlando, Florida), Applied Research Laboratories: University of Texas at Austin, Applied Physics Laboratory: University of Washington, Institute for Sensory Research: Syracuse University, Georgia Institute of Technology, Emory University, Boston University, The University of Vermont, Applied Physics Laboratory, Johns Hopkins University, Jet Propulsion Laboratory, University of Rochester, University of Minnesota, University of Illinois system, Loyola University, State University of New York at Buffalo, New York
- "Non-Lethal Swimmer Neutralization Study"; Applied Research Laboratories; The University of Texas at Austin; G2 Software Systems, Inc., San Diego; TECHNICAL DOCUMENT 3138; May 2002 Non-Lethal Swimmer Neutralization Study Archived February 10, 2012, at the Wayback Machine.
- Applications - LRAD Corporation website
- Corbett, Peter (2009). A Modern Plague of Pirates. p. 65. ISBN 0-9562107-0-8.
- Bill Sweetman. "Directed-Energy Weapons: No Longer Science Fiction Aviation Week & Space Technology, 2015. Archive
- Archimedes Death Ray: Idea Feasibility Testing
- Jones, R.V. (1978). Most Secret War: British Scientific Intelligence 1939–1945. Coronet. pp. 84,124. ISBN 0-340-24169-1.
- "Turning Up The Heat: Latest Evolution Of Lockheed Martin Laser Weapon System Stops Truck In Field Test" (Press release). Lockheed Martin. March 3, 2015. Retrieved April 8, 2015.
- Seifer, Marc J., Wizard, the Life and Times of Nikola Tesla. ISBN (HC) pg. 454.
- Martin O'Collins, director (21 February 2006). "Weird Weapons: The Axis". Modern Marvels. Season 12. Episode 8. The History Channel.
- "Forschungsstätte für Hitlers "Todesstrahlen"". Main-netz.de. 2009-08-19. Retrieved 2012-06-12.
- Wang, C. P. (Ed.), Proceedings of the International Conference on Lasers '85 (STS, McLean, Va, 1986).
- Duarte, F. J. (Ed.), Proceedings of the International Conference on Lasers '87 (STS, McLean, Va, 1988).
- U.S. Senate - Committee on Veterans Affairs: Hearings - Gulf War Illnesses; Testimony to the Senate Veterans Affairs Committee; Meryl Nass, MD, Director of Pulmonary Rehabilitation, Mount Desert Island Hospital Bar Harbor, Maine; September 25, 2007 
- Kononenko, Boris. "Silent Space Is Being Monitored". Retrieved 21 July 2011.
- Zaloga, Steven. "RED STAR WARS". Retrieved 21 July 2011.
- "STS-41-G". Astronautix.com. Retrieved 2012-06-12.
- "End of the World 2013: DE-STAR Project Proposed after Asteroid 2012 DA14 Flyby, Russian Meteor Blast", International Business Times, Feb. 22, 2013
- Human Effects Advisory Panel Program; presented to: NDIANon-Lethal Defense IV 
- Non-Lethal Weaponry: From Tactical to Strategic Applications; Colonel Dennis B. Herbert, USMC (Ret.), program developer, Institute for Non-Lethal Defense Technologies at Pennsylvania State University; pg. 4 
- Smith, David (November 22, 2006). "Pirates shoot at Britons' cruise liner". The Guardian. London.
- The E-Bomb: How America's New Directed Energy Weapons Will Change the Way Future Wars Will Be Fought. Doug Beason (2005). ISBN 0-306-81402-1
- US claims that China has used high-energy lasers to interfere with US satellites: Jane's Defence
- China jamming test sparks U.S. satellite concerns: USA Today
- Beijing secretly fires lasers to disable US satellites: The Telegraph
- China Attempted To Blind U.S. Satellites With Laser: Defense News
- China Has Not Attacked US Satellites Says DoD: United Press International
- Gertz, Bill (July 21, 2011). "Report: China building electromagnetic pulse weapons for use against U.S. carriers". The Washington Times. Retrieved April 29, 2012.
- Hambling, David (October 10, 2008). "Army Orders Pain Ray Trucks; New Report Shows 'Potential for Death'". Wired Magazine. Retrieved April 29, 2012.
- Beckhusen, Robert (April 1, 2013). "Air Force Wants New Energy Weapons to Cause Non-Lethal 'Bioeffects'". Wired Magazine. Retrieved April 1, 2013.
- Applied Energetics - Photonic and high-voltage energetics (formerly Ionatron)
- Wired News (AP) article on weapons deployment in Iraq, Active Denial System and Stunstrike, July 10, 2005
- Boeing Tests Laser-Mounted Humvee as IED Hunter, November 13, 2007
- WSTIAC Quarterly, Vol. 7, No. 1 - Directed Energy Weapons
- Ogonek Report on '21st Century Weapons'
- How 'Revolutionary' Is CHAMP, New Air Force Microwave Weapon?, November 28, 2012 By David Axe