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How LED Incapacitators Work

Inside the Incapacitator: Not Your 1970s Disco Strobe Light

­The LEDI is about the size of ­a large flashlight. Instead of a single lightbulb with a reflector and lens, the nonlethal weapon has light-emitting diodes of various colors and a plate of tiny lenses for each diode.

Batteries supply the power to the LEDI circuit board. The circuit board controls the intensity and pattern of the flashes; that is, which LED in the array turns on when, in what order and how fast. The circuit board can be programmed with different flash patterns for the LED array. For example, officers may use one mode for a stationary suspect and another for a moving person.

The plate's lenses, mostly made of fiber optics, focus the light from each LED and align the beam coming from the LED plate to a target angle of 5 degrees. The strobe may also have a range finder like the autofocus aspect of a digital camera. This feature can determine the intensity of the flashes needed to paralyze a target at various distances from the device.

Prototype LEDIs are pretty large, with a 4-inch (10-centimeter) head. Intelligent Optical Systems is working to reduce the size of the head, more like a conventional flashlight. Eventually, the plan is to have smaller LEDIs that could be mounted on a pistol, like a laser sight.

Before it can make the public wretchedly ill, researchers at Penn State's Institute for Non-Lethal Defense Technologies have to test it on volunteers. Afterward, the Los Angeles County Sheriff's Department may use the LEDI for patrols, and the U.S. Department of Homeland Security will use it for border law enforcement.

­If you're not feeling too queasy, look over the links on the next page to learn more about light, lightsabers and lasers.