POSITION MEASUREMENT OF MOVING OBJECT USING LIGHT BEAM

摘要

PURPOSE:To measure the distance of a moving body by measuring time interval at which the moving body receives two light beams to substitute the value thus obtained into the formula. CONSTITUTION:A reflector 3 is mounted on a turntable 2 constant in the rotational speed and two laser projectors 4 are arranged side by side. The angular velocities omega of laser beams LB1 and LB2 reflected with the reflector 3 doubles that of the turntable 2. A photosensor 5 mounted on a moving body is made up of a photocell 52 comprising two photodiodes 51a and 51b parallely arranged. As the laser beams LB1 and LB2 cross the photosensor 5, two pulses are generated at a fixed time interval. The time interval (t) between the two pulses is measured with a time interval measuring circuit to determine the distance lof the moving body from the formula.