To provide a DC lighting type discharge lamp realizing improvement of a life characteristic, by preventing a binding agent, mixed in a ceramic bonding agent for increasing bonding force, from sticking to a seal part of a cathode side, and suppressing generation of devitrification and leakage of the seal part.
In a DC lighting type discharge lamp bonding one seal part 23 of an emitting tube 20 made of quartz glass oppositely provided with an anode 21 and a cathode 22 to a base 27 by a ceramic bonding agent 29 containing a binding agent, in the periphery of a seal part 24 in a cathode side, a conductive member 30, connected so as to generate an equal potential to the cathode, is mounted. In this way, during lighting, a binding agent evaporated from the bonding agent 29 comes to stick to the conductive member 30, this binding agent is provided with minus potential, so as to impede draw in to quartz glass. Accordingly, reaction of the binding agent to the quartz glass is prevented, devitrification and leakage in the seal part are suppressed.
KAWASHIMA HIROMICHI
TANAKA ICHIROU
FURUYA MAMORU
MURASE NANAO
