HIGH-INTENSITY DISCHARGE LAMPS

摘要

High-intensity-discharge lamp is fabricated in a fashion generally similar to a standard high-pressure-mercury lamp which has a red-emitting phosphor coated on the outer envelope. In the present lamp, the discharge-sustaining filling in the arc tube is modified to include a small, predetermined proportion of cadmium which adds radiations of a wavelength of about 490 nm to the composite lamp emission. The resulting composite emission has greatly improved color-rendering properties as compared to a similar lamp which does not incorporate the cadmium addition to the arc tube filling.