Patent ID: 8476848

Claim:
A filament lamp lighting device wherein a plurality of filament lamps is arranged, each comprising a filament lamp having a light emission tube having with at least one sealing portion and in the interior of which at least one filament is arranged, a pair of internal leads, each of which is connected to a respective end of said at least one filament, metal power supply foils provided in said at least one sealing portion of the light emission tube and connected to said internal leads, and a pair of external power supply leads connected to said metal power supply foils for supplying of power to said at least one filament via said foils and internal leads; and a power source connected to said external power supply leads; wherein at least one metal foil for detection is provided in said sealing portion and is connected to one of a said internal lead and a said metal power supply foil, and wherein an external detection lead is connected to said at least one metal foil for detection, and wherein, between said external detection lead and said external power supply lead, a connection is established via a voltage detector connected in a manner for detecting breakage of a filament wire by detecting a voltage drop generated at the metal power supply foil.