HIGH-PRESSURE DISCHARGE LAMP

摘要

PURPOSE: To manufacture a capacitor easily at a low cost and prolong the lifetime of a high pressure discharge lamp by accommodating a voltage- subordinate capacitor of an ignition circuit in an air-tight glass capsule filled with a gas and installing it in a lamp cap. CONSTITUTION: A discharge lamp 2 is structured so that a discharge vessel 3 for performing electric discharge between electrodes 4 and 5 through rigid conductors 40 and 50 is installed in an outer bulb 30 having a lamp cap 31 in which an ignition circuit 10 is accommodated. The circuit 10 comprises a fuse 7, voltage-subordinate capacitor 8 and stabilising subordinate resistance 9, and impresses ignition voltage pulses for starting on the electrodes 4 and 5 using a circuit including a stabilizing ballast 1. The lifetime of the capacitor 8 is prolonged by accommodating it a glass capsule having a radiations reflecting layer and filled with a gas such as a rare gas or nitrogen to suppress segregation or evaporation of the component(S) during the operation, and the production can be very simply carried out with high reliability using known techniques.