H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
H05B31/00—Electric arc lamps
H05B31/0003—Electric arc lamps the arc being outside, in the open
H05B31/0009—Electric arc lamps the arc being outside, in the open with parallel or oblique disposition of the electrodes; Special form of the electrodes