An electromagnetic weapon uses electromagnetic energy to disrupt equipment or to cause unpleasant sensations, such as heat or pain, in order to subdue a human target. Typically, electromagnetic energy weapons are not intended to kill but to control people from a distance. Potential military uses include preventing unidentified persons, who may or may not be enemies, from continuing to approach soldiers. The intention is that innocent civilians are less likely to be killed by an electromagnetic weapon. Although many such weapons exist only in science fiction, directed energy weapons such as the Active Denial System (ADS), which heats the skin's surface, the Pulsed Energy Projectile (PEP) and the Advanced Tactical Laser (ATL) weapon are being developed for possible future use.
While electromagnetic radiation weapons will seem familiar to most people due to the existence of lasers, phasers and ray guns in popular science fiction books and films, in reality only a few examples of this type of weapon exist. The electromagnetic weapon is one of a range of non-lethal weapon types being researched by the US military, and it can utilize radio waves or low or high energy lasers. What is known as the Active Denial System is the electromagnetic weapon which has been most extensively developed, and which was considered for use in Afghanistan. ADS employs electromagnetic radiation to cause heating in a way which is similar to a microwave oven, although it uses millimeter waves rather than microwaves.
Millimeter waves only penetrate a short distance, about as deep as three pieces of paper. This means that they only heat surfaces, unlike microwaves, which can cook joints of meat. An intense sensation of heat is produced, which ends as soon as the skin is moved away from the electromagnetic radiation. Although the aim of ADS is to cause pain without burning, in tests some subjects have experienced burns.
Another electromagnetic weapon in development, the Pulsed Energy Projectile, uses laser pulses to deliver a shock that results in pain and paralysis. The shock occurs when the electromagnetic pulse hits a solid target, such as a person. It is thought that this type of weapon might be used to disperse crowds, but there are concerns about the unknown long-term effects and the possibility that the PEP could be used for torture. A similar type of electromagnetic weapon, the Advanced Tactical Laser, is designed to be attached to an aircraft. It is controversial whether the ATL is really a non-lethal weapon because it is capable of killing.