Patent ID: 6850009

Claim:
A high pressure discharge lamp comprising: a ceramic discharge tube with an inner space formed therein and end portions, said inner space being filled with an ionizable light-emitting material and a starter gas and an opening being formed within said end portion; an electrode system provided within said inner space; a sealing member comprising a ceramic or a cermet with a through hole formed therein, at least a part of said sealing member being fixed within said opening of said ceramic discharge tube; a metal member; and a joining portion interposed between said metal member and said sealing member, said joining portion comprising a main phase contacting said metal member and an intermediate ceramic layer contacting said sealing member and existing between said sealing member and said main phase, said main phase comprising a porous bone structure with open pores and being made of a sintered product of powder of a metal, said main phase further comprising a ceramic phase impregnated into said open pores in said porous bone structure.