Abstract: A high pressure discharge lamp used as a light source for an automobile headlight and a method of forming the high pressure discharge lamp are disclosed. The high pressure discharge lamp includes a discharge chamber portion defining a discharge chamber filled with metal halide and rare gas, a pair of opposing electrodes, a portion of each electrode respectively projecting a predetermined distance into the discharge chamber, molybdenum foils, lead wires, and a bulb. The bulb includes a tapered portion, a sealed portion, and a sealed end having portions of a molybdenum foil, an electrode, and a lead wire disposed therein.

Abstract: A discharge lamp for an automotive vehicle including a discharge bulb and an outer cover tube for covering the discharge bulb. The discharge bulb is composed of a discharge chamber portion, a pair of seal portions for sealing both ends of the discharge chamber portion, and a pair of discharge electrodes held in respective ones of the seal portions. At the end of each seal portion adjacent to the discharge chamber portion, a taper portion is provided, which is narrowest near the discharge chamber portion, and which defines an angle with respect to a tube axis of the discharge bulb of 45 degrees or less. A curvature of a tube wall of the discharge chamber portion, is substantially constant. A ratio of the minimum thickness to the maximum thickness of the tube wall measured within that angle is between 1 and 0.8. The discharge bulb and the outer cover tube are in contact, with the portion of said discharge chamber portion having the maximum outer diameter being in contact with the outer cover tube.

Abstract: A method of manufacturing a vaporized metal discharge lamp wherein a metal halide is attached to the tip of a metal rod, such as through vapor deposition or sputtering. The rod is then inserted into a light emission envelope of the lamp, and the metal halide attached to the metal rod tip is transferred to the inside of the envelope through high frequency induction heating.