Abstract: A metal halide lamp of the present invention has an arc tube formed of ceramic and a pair of opposing electrodes. This lamp includes a Pr (praseodymium) halide, a Na (sodium) halide, and a Ca (calcium) halide enclosed within the arc tube. The Pr halide content Hp [mol], the Na halide content Hn [mol], and the Ca halide content Hc [mol] satisfy the relationships of 0.4?Hc/Hp?15.0 and 3.0?Hn/Hp?25.0.

Abstract: The present invention aims at providing a metal halide lamp that (i) prevents a decline in the lumen maintenance and a deterioration of quality in appearance due to the coloring of a casing tube surrounding the arc tube, and at the same time (ii) achieves high luminous efficiency. A metal halide lamp (1) has a pair of electrodes (20a&b) placed in an arc tube (3) made of translucent ceramic, and a sodium halide is enclosed therein. The metal halide lamp (1) satisfies L/D 4, where L (mm) is the length of the space between the electrodes (20a&b) and D (mm) is the internal diameter of the arc tube (3). The metal halide lamp (1) has a casing tube (2) surrounding the arc tube (3), at least around a portion between the electrodes (20a&b). Here, R/r 3.

Abstract: A metal halide lamp includes a ceramic arc tube that is composed of a main body and two narrow tube parts provided at respective ends of the main body; a pair of electrodes provided inside the main body; two feeders, each being connected at one end thereof to a different one of the electrodes inside the main body, and extending through a different one of the narrow tube parts, so as to be external to the arc tube at another end; a starting wire that is connected to one of the feeders, and that is in a vicinity of or contacts an outer surface of the arc tube; and a current suppressing unit that is on a current path of the starting wire, and suppresses or cuts off current on the path.

Abstract: The present invention provides a metal halide lamp in which the change of the color temperature is suppressed regardless of the orientation of the light emitting bulb in use. The metal halide lamp includes a light emitting bulb of translucent ceramics that includes a light emitting portion and tubular portions that are connected to the light emitting portion. The light emitting portion includes a liquid holding portion on the inner surface of the light emitting portion so as to hold a liquefied substance that moves on the inner surface toward one of the tubular portions. The internal diameter d of the light emitting bulb at the liquid holding portion satisfies 0.4D<d<0.7D, where D is an internal diameter of the light emitting bulb at the maximum internal diameter portion of the light emitting portion.

Abstract: A metal halide lamp in which an arc tube is housed within a bulb having a base at one end thereof. The arc tube includes a main tube, two thin tubes that extend one from each end of the main tube, and a pair of electrode inductors. The main tube and the thin tubes are made from translucent polycrystalline alumina and constitute a discharge vessel having a discharge space therein. Lamp power under dimming conditions is set in a range defined by maximum lamp power Wmax [W] and minimum lamp power Wmin [W], with a surface area S [cm2] of the inner surface of the discharge vessel satisfying Wmax/60?S?Wmin/20.

Abstract: A metal halide lamp of the present invention has an arc tube formed of ceramic and a pair of opposing electrodes. This lamp includes a Pr (praseodymium) halide, a Na (sodium) halide, and a Ca (calcium) halide enclosed within the arc tube. The Pr halide content Hp [mol], the Na halide content Hn [mol], and the Ca halide content Hc [mol] satisfy the relationships of 0.4?Hc/Hp?15.0 and 3.0?Hn/Hp?=25.0.

Abstract: A metal vapor discharge lamp, comprises: a translucent ceramic envelope, the envelope comprising a center bulb for defining a discharge space and side tubes, the center bulb and the side tubes being integrally molded; a pair of current suppliers extending through hollows of the side tubes respectively, each of the current suppliers comprising an electrode and a lead-in wire, a first end of the electrode being disposed in the discharge space, a second end of the electrode being connected with the lead-in wire; a sealant for hermetically sealing open ends of the side tubes; and a light-emitting metal contained in the discharge space. An inner wall and an external wall of a seamless boundary portion between the center bulb and each of the side tubes have the smallest curvature radius of Ri mm and Ro mm, respectively. The center bulb has an inner diameter of D mm. The lamp has an electric power of P watts. The radius Ri, radius Ro, diameter D and electric power P satisfy, ?0.00076P+0.304?Ri/D??0.00076P+0.

Abstract: A metal halide lamp has an arc tube that includes: a pair of electrode structures, each of which has an electrode at a tip; a main tube part made of polycrystalline alumina ceramic, and containing a discharge space in which the electrodes of the electrode structures are located to oppose each other; and a pair of thin tube parts that connect from the main tube part and are sealed by respective sealing members with the electrode structures inserted therein, where 20?WL?50, EL/Di?2.0, and 0.5?G?5.

Abstract: A metal halide lamp has an arc tube including an arc tube container made of an oxide-based translucent ceramic material. The arc tube is filled with cerium halide as a luminescent material and a halide of a rare earth element that is more reactive with the ceramic material than is the cerium halide. Accordingly, a reaction between the oxide-based translucent ceramic material and the halide of a rare earth element is accelerated while a reaction between the oxide-based translucent ceramic material and the cerium halide is suppressed. This suppresses a decrease of the cerium halide that serves for light emission, and also reduces changes in the lamp color temperature. Thereby, during aging of the lamp, the flux maintenance factor and color temperature are improved. Therefore, the indoor-outdoor metal halide lamp provides a white light source color that has high-wattage, high luminous efficiency, and a long service life.

Abstract: A first electrode part in a rod shape is placed on an upper side, and a second electrode part in a rod shape having a higher melting point than that of the first electrode part is placed on a lower side, so that ends of the first and second electrode parts are brought into contact. Contact ends or vicinities thereof are irradiated with a laser beam, so that the electrode parts are welded. Here, a region irradiated with the laser beam is in a long narrow shape having a minor axis directed in a vertical direction and a major axis directed in a horizontal direction. This makes it possible to manufacture an electrode with a consistent high quality with a high yield.

Abstract: A first electrode part in a rod shape is placed on an upper side, and a second electrode part in a rod shape having a higher melting point than that of the first electrode part is placed on a lower side, so that ends of the first and second electrode parts are brought into contact. Contact ends or vicinities thereof are irradiated with a laser beam, so that the electrode parts are welded. Here, a region irradiated with the laser beam is in a long narrow shape having a minor axis directed in a vertical direction and a major axis directed in a horizontal direction. This makes it possible to manufacture an electrode with a consistent high quality with a high yield.

Abstract: A metal vapor discharge lamp including an arc tube 1 that includes a container 10 and power transmission members 20a and 20b. The container 10, made of translucent ceramic, is divided into a main tube portion 11 and narrow tube portions 12a and 12b extending out from both ends of the main tube portion 11. The power transmission members 20a and 20b respectively include electrode pins 21a and 21b made of tungsten. Coils 22a and 22b made of tungsten are respectively wound around ends of electrode pins 21a and 21b, which are respectively joined with electrode supporting members 23a and 23b made of conductive cermet. Electrode length L1 is set to (0.041P+0.5) mm to (0.041P+8.0) mm, “P” representing a lamp power in watts. Alternatively, a narrow tube portion length L2 is set to (0.032P+3.5) mm to (0.032P+8.0) mm inclusive.

Abstract: To provide a high-efficiency and long-life high intensity discharge lamp that is obtained by a configuration in which a neon gas or a neon-based gaseous mixture is filled as a starting-assistance rare gas for an alumina ceramic arc tube, and a filling pressure is set to 13 kPa or more. The high intensity discharge lamp is provided with the alumina ceramic arc tube having a discharge arc tube, alumina ceramic narrow tubes formed at both end portions of the discharge arc tube, electrodes and power feeders, the electrodes and the power feeders being arranged to form spaces in the narrow tubes. The discharge arc tube is filled with the neon gas or the neon-based gaseous mixture as the starting-assistance rare gas at a filling pressure of 13 kPa or more.

Abstract: A metal halide lamp in which an arc tube is housed within a bulb having a base at one end thereof. The arc tube includes a main tube, two thin tubes that extend one from each end of the main tube, and a pair of electrode inductors. The main tube and the thin tubes are made from translucent polycrystalline alumina and constitute a discharge vessel having a discharge space therein. Lamp power under dimming conditions is set in a range defined by maximum lamp power Wmax [W] and minimum lamp power Wmin [W], with a surface area S [cm2] of the inner surface of the discharge vessel satisfying Wmax/60?S?Wmin/20.

Abstract: A first electrode part in a rod shape is placed on an upper side, and a second electrode part in a rod shape having a higher melting point than that of the first electrode part is placed on a lower side, so that ends of the first and second electrode parts are brought into contact. Contact ends or vicinities thereof are irradiated with a laser beam, so that the electrode parts are welded. Here, a region irradiated with the laser beam is in a long narrow shape having a minor axis directed in a vertical direction and a major axis directed in a horizontal direction. This makes it possible to manufacture an electrode with a consistent high quality with a high yield.

Abstract: A first electrode part in a rod shape is placed on an upper side, and a second electrode part in a rod shape having a higher melting point than that of the first electrode part is placed on a lower side, so that ends of the first and second electrode parts are brought into contact. Contact ends or vicinities thereof are irradiated with a laser beam, so that the electrode parts are welded. Here, a region irradiated with the laser beam is in a long narrow shape having a minor axis directed in a vertical direction and a major axis directed in a horizontal direction. This makes it possible to manufacture an electrode with a consistent high quality with a high yield.

Abstract: The present invention provides a metal halide lamp having a ceramic arc tube vessel that includes a discharge arc tube member and thin tube members, the discharge arc tube member including taper parts and a main tube part in the middle in a longitudinal direction, the taper parts and the main tube part having a larger outside diameter than an outside diameter of ends of the discharge arc tube in a longitudinal direction, and the thin tube members each being fit to the respective ends of the discharge arc tube, where a minimum curvature radius R is set to be 0.3 mm or more at each transitional area of an external surface between each taper part and a corresponding end of the discharge arc tube.

Abstract: A first electrode part in a rod shape is placed on an upper side, and a second electrode part in a rod shape having a higher melting point than that of the first electrode part is placed on a lower side, so that ends of the first and second electrode parts are brought into contact. Contact ends or vicinities thereof are irradiated with a laser beam, so that the electrode parts are welded. Here, a region irradiated with the laser beam is in a long narrow shape having a minor axis directed in a vertical direction and a major axis directed in a horizontal direction. This makes it possible to manufacture an electrode with a consistent high quality with a high yield.

Abstract: A metal vapor discharge lamp, comprises: a translucent ceramic envelope, the envelope comprising a center bulb for defining a discharge space and side tubes, the center bulb and the side tubes being integrally molded; a pair of current suppliers extending through hollows of the side tubes respectively, each of the current suppliers comprising an electrode and a lead-in wire, a first end of the electrode being disposed in the discharge space, a second end of the electrode being connected with the lead-in wire; a sealant for hermetically sealing open ends of the side tubes; and a light-emitting metal contained in the discharge space. An inner wall and an external wall of a seamless boundary portion between the center bulb and each of the side tubes have the smallest curvature radius of Ri mm and Ro mm, respectively. The center bulb has an inner diameter of D mm. The lamp has an electric power of P watts.

Abstract: A metal vapor discharge lamp including an outer tube having a closed portion at a first end and a base at a second end; a discharge tube inside of which an electrode is provided, located in the outer tube; and a sleeve enveloping the discharge tube and located in the outer tube, wherein the sleeve includes an open portion on the closed portion side of the outer tube; the closed portion side of the outer tube is provided with a support for supporting an end of the closed portion side of the sleeve; the support comprises a column portion having a narrow plate shape or a narrow stick shape separated from the open portion of the closed portion side of the sleeve, and a sleeve holding portion provided at an end of the column portion and is in contact with the sleeve; and the support is connected to a feeding body connected to the electrode and led from the discharge tube toward the side of the closed portion, and the support also is connected to an electric power supply wire extending toward the side of the base.