IRRADIATING DEVICE FOR LIGHT BEAM

摘要

PURPOSE:To enable a reduction optical system to stop down the exit light of an optical fiber without losses by stopping the light emitted from a conical mirror which is provided at the exit end of the optical fiber and decreases the spreading angle of the exit light by the reduction optical system. CONSTITUTION:The one end face of the optical fiber 3 is disposed at the 2nd focus of an elliptic reflecting mirror 2 and all the light from a xenon lamp 1 reflected by the elliptic reflecting mirror 2 is made incident on this end face of the optical fiber 3. The conical mirror 5 is mounted to the exit end which can move its position freely relative to a body 4 to be irradiated and a lens 6 used as the reduction optical system is disposed at the end thereof. Then, the body 4 to be irradiated is irradiated with light emitted from the xenon lamp 1 at either of the incident end face and exit end face of the optical fiber 3 with substantially no losses. Most of the light is condensed at the lens 6 even if the lens 6 is so adjusted as to part from the exit end face 3a in order to reduce the beam diameter at the exit end. The loss in the reduction optical system is eliminated in this way.