Spot light-source device excited by electromagnetic energy

Abstract

To provide a spot light-source device whose discharge envelope has high pressure resistance and that emits high brightness as a spot light source, a spot light-source device excited by electromagnetic energy has a lamp that with a discharge envelope made of translucent non-conducting material, an expansion part forming a discharge space, and a tube connected thereto, and a discharge concentrator having a front tip part which is supported by the tube without protruding from the discharge envelope and faces the interior of the discharge space of the expansion part, that intensifies concentration of the electric field in the discharge space and that concentrates discharge, an electromagnetic energy provision source that excites discharge in the discharge concentrator from outside of the lamp, a concave reflection mirror that reflects light from the lamp, and a container with a resonance window that creates electromagnetic energy resonance. The lamp and the concave reflection mirror are housed with the container, and the contain is constructed to prevent leakage of electromagnetic energy from an aperture that emits light collected light from the lamp and concave reflection mirror.