Patent ID: 9576784
Date: 2017-02-21
CPC Classifications: F21S,H01J

Claim:
1. An electrical gas-discharge lamp comprising: an inner bulb and an outer bulb, the inner bulb being arranged within the outer bulb, said inner bulb being filled with a discharge gas and comprising a first electrode and an opposing second electrode having a distance from the first electrode which allows ignition of a gas discharge in the inner bulb by applying an ignition voltage between the electrodes, said first electrode being electrically contacted by a first electrically conductive lead, which extends in a first electrically insulating feedthrough on a first side of the inner bulb through the outer bulb, said second electrode being electrically contacted by a second electrically conductive lead extending in a second electrically insulating feedthrough on a second side of the inner bulb through the outer bulb, and said outer bulb being filled with a second gas, at least one through hole is formed in the first feedthrough to the first electrically conductive lead and an electrically conductive member extends within a space formed between the inner and the outer bulb at least from a position close to the through hole to a distance from the second electrode which is smaller than the distance between the two electrodes, said position of the electrically conductive member close to the through hole being such that, prior to ignition of the lamp, the electrically conductive member is not electrically connected to said first electrically conductive lead, and such that an electrically conducting path forms through the through hole between the electrically conductive member and the first electrically conductive lead by ionization of the second gas when applying said ignition voltage between the electrodes.