Laser-activated switch.

One of the latest developments out of Los Alamos (N.M.) National Laboratory is the super-fast, high-power electrical switch. A pulse of laser light activates the device, turning electricity on in less than a billionth of a second.

The principle behind the photoconductive switch is similar, at a much more powerful level, to that of the familiar "electric eye" that operates mechanical doors. William Nunnally (above), the switch's developer, says the new switch is at least 10 times faster and more precise than any existing high-power switch. It is also safer than conventional switches since the operator is not in direct contact with the high voltage.

Los Alamos plans to use the switch for particle accelerators, laser applications and "Star Wars" research.