公开(公告)号：US06800997B2

公开(公告)日：2004-10-05

申请号：US10106214

申请日：2002-03-27

Applicant: Hirofumi Yamashita ,  Haruo Yamazaki ,  Toshihiro Terada ,  Shinji Kihara

Inventor： Hirofumi Yamashita ,  Haruo Yamazaki ,  Toshihiro Terada ,  Shinji Kihara

IPC: H01J6109

CPC classification number: H01J61/067 ,  H01J61/72

Abstract: The present invention has an object to provide a cold-cathode fluorescent lamp which can suppress sputtering caused by electric discharge and reduce consumption of mercury so as to achieve a longer lifetime even if a lamp current is large and a lighting tube has a small diameter. The cold-cathode fluorescent lamp according to the present invention is characterized in that a distance between the inner surface of the lighting tube and the outer surface of a cylindrical electrode is set such that electric discharge develops mainly on the inner surface of the cylindrical electrode. When the lighting tube has an inside diameter D1 of 1 to 6 mm and the maximum lamp current is 5 mA or more, an outside diameter D2 of the cylinder electrode is preferably set at D1−0.4 [mm]≦D2