GENERATION OF HARMONICS FROM LASER OUTPUT

摘要

A system for producing harmonics from a laser beam in which the beam is passed through a non-linear device such as a non-linear crystal. The harmonic ouptut from the crystal must be in phase with the original laser beam on exiting the crystal for the two constructively to reinforce one another. The angle at which the laser beam leaves the laser can change randomly due to such effects as local heating around the laser window and the present invention provides an optical system which ensures that the angle of incidence of the laser beam on the crystal does not alter even when the laser beam wanders due to this effect so that constructive reinforcement of the two beams is unaffected by the random movement of the laser beam.