LIGHTING DEVICE OF DISCHARGE LAMP

摘要

The ignition circuit has a delay circuit to displace the conduction angle of the semiconductor switch that shants the lamp on the opposite side of the latter's two heating filaments to the ballast inductor and the ac voltage supply. The s-c switch is shunted by a non-linear dielectric component. The delay circuit increases in steps the positive needle-pulse voltage appearing at the non-linear dielectric components so as to increase the lamp life by reducing the evaporation of material from the heating filaments. The increase occurs for period by period of the ac supply votage.