The Active Denial System (ADS), a non-lethal directed energy weapon system, was developed by the United States military. The system emits a beam that is millimeter wide, also called "heatrays", that targets people. When the beam hits the target, it emits a heating sensation that causes a temporary burn. This heating effect can be used to stop an individual engaging in hostile activities.
An active denial system can be mounted on ceilings or walls, as well as ships. They can also be used to control crowds and perimeter security. The device is non-lethal and can be used to defend high-asset bases. It can also be used to enforce law. However, some people feel that the technology can be misused or is too dangerous.
ADS works by sending a beam at 95 GHz of millimeter waves to a target. These waves penetrate skin to a depth 1/64th an inch. If the subject moves out of the beam, the energy is stopped. The beam can cause skin blisters and pain.
Although the technology is still new, Air Force Research Laboratory's Human Effectiveness Directorate has done the research and testing. The Human Effects Advisory Panel reviewed the test results and concluded that exposure to ADS poses no risk of serious injury.
The Active Denial System has been tested on people wearing contact lenses and concrete blocks. It also works against alcohol and tin foil. These tests were done in accordance to Federal regulations for human research. The beam, unlike a gun, is not absorbed into metal and can therefore be used to target multiple targets. Also, the head turn provided by the system helps to protect the eyes.
Active Denial Systems has been shown to protect against pirate attacks. However it is not known how it would operate in a combat situation. It could be used to defend high-asset military bases or oil and cargo ships from piracy. At present, the military version is a vehicle-mounted weapon, while the civilian version is more portable.
Since the late 1980s, the Air Force has been investigating the effects on Active Denial Systems. Joint Non-Lethal Weapons Program (an organization that strives to improve the lives of service personnel) has funded the development and funding of Active Denial Technology systems. In support of this effort, the Air Force Research Laboratory's Human Effectiveness division has done years of safe laboratory testing.
Active Denial technology has been featured in the History Channel's Modern Marvels program, as well as CBS 60 Minutes. It's also featured in Discovery Channel's Future Weapons series. However, the government is hesitant to use Active Denial Systems in a war situation. The United States has instead used "less lethal" weapons regularly.
Active denial systems are designed for attackers to have additional time to decide. This beam is reversible at short and long ranges.