Patent ID: 7420191

Claim:
Radiation source comprising: an anode ( 2 ); a cathode ( 3 , 8 ); a discharge space ( 4 ) for electrical discharge between the anode ( 2 ) and the cathode ( 3 ); a gas inlet pipe ( 30 ) for introducing gas into the discharge space ( 4 ), the gas inlet pipe ( 30 ) being electrically connected to one of the anode ( 2 ) and the cathode ( 3 , 8 ); an electrically insulating assembly ( 34 ) for the source; means ( 13 to 23 ) for producing, in the gas provided in the discharge space ( 4 ), an electrical discharge which brings about emission of electromagnetic radiation towards outside the discharge space; and a gas supply line ( 43 ) that has a first portion ( 44 ) connected to a fixed potential and a second portion ( 42 ) connected to the gas inlet pipe ( 30 ) and that comprises, between the first portion and the second portion, an electrically conductive material, the gas supply line ( 43 ) being wound helically against and spaced from the electrically insulating assembly ( 34 ), so that production of electrical discharges inside the gas inlet pipe ( 30 ) is inhibited.