HIGH LUMINANCE ELCTRODELESS PROJECTION LAMP

摘要

An Electrodeless High Intensity Discharge (EHID) lamp for projection applications. The lamp has a small (nominal dimensions: 2mm I.D., 3mm O.D., 6mm internal length) capsule, which is constricted in a mid-portion thereof. The constriction squeezes the plasma within the capsule and provides a higher power density. This in turn produces a higher luminance in the center of the arc. This focal point of the projection system is constant over the life of the lamp, owing to t he fact that the system is electrodeless. The arc tube or capsule is thickened in the vi cinity of the constriction to permit heat transfer through the vitreous silica (commonly c alled quartz). The thickening carries the heat away from the now hotter mid-portion ar ea. This thickening cools by virtue of increasing the thermal conduction through the glass.