Patent ID: 7041240

Claim:
A method of manufacturing a vessel for a high pressure discharge lamp, said vessel comprising a main portion forming a discharge space, and end portions into which respective electrode members are inserted, said main portion and said end portions being integrally made of a transparent or translucent material, comprising the steps of: providing a mold comprising a core made of an air permeable material and a plurality of packing members surrounding said core and defining a vacuum chamber between an inner surface of at least a portion of said packing members and an outer surface of said core; providing a tubular member made of a transparent or translucent material; setting said tubular member into said core of said mold; heat-treating at least said core of said mold; and decompressing a space between an outer surface of said tubular member and an inner surface of said core to thereby bring said tubular member into contact with said core so that an outer shape of said tubular member coincides with said inner surface of said core.