Arc discharge lamp with starter electrode voltage doubling

Abstract From the Canadian patent

In a discharge lamp where the arc tube has main electrodes and a starter electrode, there is provided a voltage doubling circuit comprising a diode and a capacitor connected in series across the input terminals. The circuit is poled to generate a positive potential at the junction of diode and capacitor which is coupled through a resistor to the starter electrode. Voltage doubling may be provided across the gap from starter to adjacent main electrode or from starter to remote main electrode to improve starting. Where the arc tube contains sodium, the positive potential may also be applied to the arc tube frame to reduce sodium loss by electrolysis.