Patent ID: 6020594
Filing Date: 2000-02-01
Classification: G01P

Abstract:
Apparatus for measuring the velocity of a projectile, comprising:(a) a base for placement in spaced relation to a ballistic path to be traversed by the projectile;(b) first and second sensor units spaced longitudinally on the base for sequentially responding to passage of the projectile, each of the sensor units comprising a facing pair of first and second parabolic slit mirrors supported on opposite sides of the ballistic path, a radiation source supported at a focal point of the first mirror for directing radiation against the first mirror and a radiation detector supported at a focal point of the second mirror, the radiation being approximately collimated by the first mirror, at least a portion of the radiation being redirected and focused onto the radiation detector by the second mirror, a portion of the radiation onto the detector being interrupted by passage of the projectile between the mirrors; and(c) a circuit responsive to the detectors for determining a measured quantity being a function of an average velocity of the projectile between the sensor units.