SPUTNIK / SCIENCE PHOTO LIBRARY SPUTNIK / SCIENCE PHOTO LIBRARY
Traffic police speed trap. Road traffic police officer using a Radis portable mini radar speed gun. The device works by bouncing a radar beam off the vehicle and comparing the frequency of the reflected signal to that of the initial output. Due to the doppler effect, the reflected frequency is lowered by a factor that depends on the speed of the moving object. Photographed in Kaliningrad, Russia.
Model release not available. Property release not available.