ARC DISCHARGE LAMP CONTAINING MECHANISM FOR EXTINGUISHING ARC AT END-OF-LIFE

摘要

D-92-1-005 PATENT APPLICATION An arc discharge lamp having an end-of-life structure and including a light-transmissive envelope having a tubular-shaped main body and a press seal disposed at each end of the main body. An electrode filament having a pair of ends is located in each end of the envelope. Each electrode filament end is in a contiguous relationship with an inside surface of the lamp envelope. When one of the electrode filaments is depleted of electron-emissive material, increased heating of the electrode filament caused by an increase in cathode fall voltage, produces a localized hot spot on the internal surface of the envelope. This localized heating causes a puncture in the lamp envelope and evacuation of the lamp. The introduction of external atmosphere into the lamp extinguishes the arc discharge and renders the lamp inoperable.