Abstract: A Hg-free metal halide lamp comprising a substantially cylindrical discharge vessel with a ceramic wall having an internal diameter Di, an internal length Li and a wall thickness Wt, and filled with an ionizable filling, wherein two electrodes are present having a mutual distance EA for maintaining a discharge in the discharge vessel, wherein the filling comprises an inert gas and a salt, wherein the internal length Li is smaller than 8 mm, wherein the electrode distance EA and the internal diameter Di comply with the relation EA/Di>;2, wherein the inert gas pressure PXe at room temperature is at least 5 bar, and wherein the wall thickness Wt and the internal diameter Di comply with the relation Wt/Di>0.15.

Abstract: Vehicle headlamp with a metal halide lamp comprising: a discharge vessel surrounded with clearance by an outer envelope and having a ceramic wall which encloses a discharge space containing Xenon (Xe) and an ionizable filling; a first and a second current conductor entering the discharge vessel and each supporting an electrode in the discharge vessel, wherein the first and the second current conductor each extend from a ceramic sealing compound sealing the discharge vessel around the current conductors in a gastight manner to the exterior of the discharge vessel, and wherein the discharge vessel has extended end parts in each of which a respective current conductor is enclosed, which plugs each have a free end where the discharge vessel is sealed by the ceramic sealing compound; with the special feature that said vehicle headlamp has a lightreflective coating surrounding at least a portion of at least one of the end parts.

Abstract: The present invention relates to a discharge vessel (1) with at least one end part (2) and a discharge cavity (3), whereby the discharge vessel (1) is at least partly coated with a coating layer (4), and whereby the gas-tight bonding of the coating layer to the discharge vessel (1), to a sealant (5) and/or to an end closure member (9) is stronger compared to the direct gas-tight bonding of said sealant (5) to said end closure member (9) and/or discharge vessel (1).

Abstract: A Hg-free metal halide lamp comprising a substantially cylindrical discharge vessel with a ceramic wall having an internal diameter Di, an internal length Li and a wall thickness Wt, and filled with an ionizable filling, wherein two electrodes are present having a mutual distance EA for maintaining a discharge in the discharge vessel, wherein the filling comprises an inert gas and a salt, wherein the internal length Li is smaller than 8 mm, wherein the electrode distance EA and the internal diameter Di comply with the relation EA/Di>;2, wherein the inert gas pressure PXe at room temperature is at least 5 bar, and wherein the wall thickness Wt and the internal diameter Di comply with the relation Wt/Di>0.15.

Abstract: The invention relates to a high-pressure discharge lamp which is provided with a discharge vessel which encloses a discharge space. The discharge vessel has a ceramic wall and is closed by a ceramic plug. An electrode which is located inside the discharge space is connected to an electric conductor by way of a leadthrough element. The leadthrough element projects through the ceramic plug with a close fit and is connected thereto in a gastight manner by way of a sealing ceramic. The leadthrough element has a first part which is formed by a cermet at the area of the gastight connection. In accordance with the invention the leadthrough element has a second part which is a metal part which extends from the cermet in the direction of the electrode.

Abstract: A high-pressure metal halide discharge lamp having a power rating of at most 100 W is provided with a discharge vessel having a translucent ceramic wall with a thickness d of at least 1.2 mm. In the discharge space enclosed thereby, two electrodes are arranged with their electrode tips at a mutual interspacing EA. The discharge vessel contains an ionizable filling comprising at least Na and a halide.

Abstract: The invention relates to a high-pressure discharge lamp which is provided with a discharge vessel which encloses a discharge space. The discharge vessel has a ceramic wall and is closed by a ceramic plug. An electrode which is located inside the discharge space is connected to an electric conductor by way of a leadthrough element. The leadthrough element projects through the ceramic plug with a close fit and is connected thereto in a gastight manner by way of a sealing ceramic. The leadthrough element has a first part which is formed by a cermet at the area of the gastight connection.

Abstract: A high-pressure discharge lamp includes a ceramic discharge vessel which encloses a discharge space containing two electrodes and an ionizable filling including a metal halide. The discharge vessel includes a central cylindrical part with an end, and an end part closing the cylindrical part at the end in a gastight manner. The discharge vessel also has a projecting plug connected to the end part in a gastight manner for enclosing a feedthrough conductor. The end part is monolithic and its outside surface includes an angle A with the longitudinal axis of the discharge vessel at the projecting plug, where the angle A is between 30 and 60 degrees. The outside surface of the end part may be shaped like a truncated cone with a base extending radially outward. Alternatively, the end part includes two concentric tubular portions which are interconnected in a gastight manner.

Abstract: Metal halide lamp radiates light with a color temperature T.sub.c of between 3900 K and 4200 K and with a general color rendering index R.sub.a .gtoreq.90. The ionizable metal halide filling comprises between 30 and 50 mole % CaI.sub.2. The lamp has a limited crest factor, and accordingly a long useful life.

Abstract: A high-pressure discharge lamp of the invention includes a ceramic discharge vessel (10) in which a first and a second electrode (40a, 40b) are arranged and which encloses a discharge space (11 ) which is provided with a filling containing a metal halide. The discharge vessel (10) has a central zone (20) between the electrodes (40a, 40b) and a first and a second cylindrical end zone (30a, 30b) which each surround a current supply conductor (50a, 50b) connected to a respective electrode (40a, 40b). At least the first end zone (30a) has a diameter smaller than the smallest diameter of the central zone (20). The current supply conductor (50a) through the first end zone (30a) has a halide resistant portion (51a) which faces the discharge space (11) and a portion (52a) permeable to hydrogen and oxygen and facing away from the discharge space (11).