Patent ID: 8304998

Claim:
Dimmable light generating device, comprising: a tubular gas discharge lamp ( 301 ), comprising a plurality of tube segments ( 11 , 12 , 13 , 14 ) arranged substantially parallel to each other, the tube segments having an axial length, the number of tube segments being an even integer, each tube segment having an interior space, the tube segments being coupled to each other by transverse tube segments ( 31 , 32 , 33 ) so that the interior space of one tube segment always communicates with the interior space of at least one other tube segment; a first lamp electrode filament ( 21 ) arranged within the interior space of a first tube segment ( 11 ) at a proximal end of said first tube segment, with first electrode terminals extending to outside of said first tube segment; a second lamp electrode filament ( 22 ) arranged within the interior space of a last tube segment ( 14 ) at a proximal end of said last tube segment, with second electrode terminals extending to outside of said last tube segment; the device further comprising an electrically conductive external auxiliary electrode ( 310 ; 810 ), which auxiliary electrode is arranged outside the tube segments ( 11 , 12 , 13 , 14 ) and has an axial extent corresponding to the axial length of the tube segments, and which auxiliary electrode is capacitively coupled to all tube segments and is coupled to a reference voltage level.