lep

"The principle of a LEP can be compared to a light-activated switch. The light source, however, has been replaced by the light pistol. By pulling the trigger of the LEP a short flash of light is emitted. This flash of light is produced by a lamp built into the barrel of the pistol. A microswitch operated by the trigger, connects a previously charged capacitor across the lamp. Via this lowresistance load the capacitor discharges quickly. As a result the lamp lights momentarily. To increase the intensity the lamp is briefly loaded with three to four times its nominal voltage . Moreover, the light flash is focussed by a biconvex lens into a parallel beam."