Abstract: A discharge lamp for a vehicle is provided with a ceramic luminous tube, a front side electrode and a rear side electrode held by the ceramic luminous tube, a first lead wire connected to the front side electrode, a second lead wire connected to the rear side electrode, a third lead wire having a front end portion connected to the first lead wire, an outer tube, and a socket. The ceramic luminous tube, the first lead wire, the second lead wire and the third lead wire are accommodated in the outer tube. The ceramic luminous tube includes a luminous portion and a pair of small diameter tube portions. The luminous portion is formed into a substantially cylindrical shape extending in a longitudinal direction. The third lead wire includes a horizontal portion extending in the longitudinal direction above the luminous portion.

Abstract: A discharge bulb and an arc tube are provided. The discharge bulb includes an arc tube main body having a discharge arc chamber, in which two discharge electrodes are disposed to oppose to each other; a tube portion disposed at each end portion of the arc tube main body, each of the tube portions being in communication with the discharge arc chamber and holding one of the discharge electrodes, wherein a wall for forming the discharge arc chamber has a taper portion whose diameter is reduced gradually from a cylinder portion of the arc tube main body in a center area to the tube portion of the arc tube main body, and an inner diameter Di of the cylinder portion is about 1.0 mm to about 2.5 mm, and a projection length Le of the discharge electrode into the discharge arc chamber is about 1.5 mm to about 2.5 mm.

Abstract: A direct-current high-voltage discharge bulb includes a ceramic arc tube body having a discharge emission chamber at a middle portion in a longitudinal direction thereof, a light-emitting substance which is sealed inside the discharge emission chamber together with a starting rare gas, and an anode and a cathode which are disposed so as to face each other inside the discharge emission chamber. An inside diameter of the ceramic arc tube body where the discharge emission chamber is defined is made to gradually decrease from the anode side to the cathode side.

Abstract: A discharge lamp includes a coaxial waveguide for high-frequency electromagnetic wave transmission and a discharge tube for emitting light of discharge by plasma generated by electromagnetic waves. The coaxial waveguide includes an internal conductor and a pipe-shaped external conductor surrounding the internal conductor. The discharge tube is attached to a top of the coaxial waveguide, and is constructed in a double end shape in which both ends of a glass tube are pinched and sealed. The glass tube includes an ellipse spherical bulged part formed in a middle of a longitudinal direction. An inside of the ellipse spherical bulged part forms discharge space. A conductor assembly is sealed and attached to at least a proximal side pinch seal part. The proximal side pinch seal part of the discharge tube is inserted and held in a top opening of the coaxial waveguide.

Abstract: A high-frequency discharge lamp includes a coaxial waveguide including an internal conductor and a pipe-shaped external conductor surrounding said internal conductor, and a discharge tube including a ceramic or glass tube having an approximately ellipse spherical bulged part formed in a middle of a longitudinal direction, and both ends pinched and sealed; a conductor assembly sealed and attached to an end of the ceramic or glass tube; and an auxiliary electrode for starting disposed near the approximately ellipse spherical bulged part. A rare gas for starting with 1 atmospheric pressure or more at room temperature together with a light emission substance is enclosed inside of the approximately ellipse spherical bulged part. The discharge tube is inserted conductor assembly end first and held in a top opening of the coaxial waveguide. A high-voltage pulse generated by a high-voltage pulse generator is applied to the auxiliary electrode through a pulse transmission line.

Abstract: A discharge bulb is equipped with an arc tube main unit including in a ceramic tube a discharge light emitting chamber where electrodes are provided face to face and a luminescent material is filled, with substantially the lower half of the outer peripheral surface of the ceramic tube covered by a light shielding ember. Light to be emitted from the ceramic tube is also emitted from the upper part and directed to the efficient reflecting surface of the reflector thus raising the luminance intensity of the headlamp. In the process of light distribution design of the reflector, the size of the rectangular light source image to be projected (stuck) along the cutoff line is made slimmer (narrower). By perform light distribution design (of the effective reflecting surface) so as to allow the maximum luminance part to approach the cutoff line, the hot zone gets closer to the cutoff line position with improved long distance visibility.

Abstract: An arc tube for a discharge bulb is provided for use in a vehicular lighting system. The arc tube includes a closed glass bulb that is pinch-sealed at opposite ends. Inner ends of a first electrode and a second electrode extend into the closed glass bulbs from the ends of the closed glass bulb. The atmosphere inside the closed glass bulb includes a starting rare gas, a primary light-emitting metal halide, and optionally, a buffer metal halide. The distance between the inner ends of the electrodes is between about 0.3 and 1.8, and the inner diameter of the closed glass bulb at a middle portion is between about 1.5 mm and 2.7 mm. Accordingly, a stable discharge is produced using between 15 W and 30 W of power.

Abstract: In a discharge lamp device, the arc tube body is configured by welding and integrating shroud glass with an arc tube so as to enclose a discharging portion, and a rearward elongating portion of the arc tube that elongates in the rear of the shroud glass is inserted and held into an opening of an insulating plug which is made of synthetic resin. A UV blocking film is formed on the outer surface of the rearward elongating portion of the arc tube. UV components of leakage light from the rearward elongating portion are cut off, and the amount of ultraviolet rays to which the resin layer in the opening is exposed is reduced. The UV blocking film is in the opening, and hence cannot be seen through a front lens.

Abstract: A discharge bulb comprising an arc tube body having such a structure that a shroud glass having metal oxide (Al2O3, CeO2) added thereto is attached integrally to surround an arc tube sealing Hg, NaI, ScI and Xe gases. A total amount of addition of the metal oxide in the shroud glass is set to be 4000 ppm or more which is effective for fulfilling an electrostatic shielding function for an external electric field and less than 7000 ppm which can hold the excellent molding property of the shroud glass.

Abstract: An arc tube for a discharge bulb is provided for use in a vehicular lighting system. The arc tube includes a closed glass bulb that is pinch-sealed at opposite ends. Inner ends of a first electrode and a second electrode extend into the closed glass bulbs from the ends of the closed glass bulb. The atmosphere inside the closed glass bulb includes a starting rare gas, a primary light-emitting metal halide, and optionally, a buffer metal halide. The distance between the inner ends of the electrodes is between about 0.3 and 1.8, and the inner diameter of the closed glass bulb at a middle portion is between about 1.5 mm and 2.7 mm. Accordingly, a stable discharge is produced using between 15 W and 30 W of power.

Abstract: A mercury-free arc tube includes a closed glass bulb held between pinch seal portions located at opposite ends of the close glass bulb; and a pair of electrodes provided in the closed glass bulb so as to be opposite to each other. The closed glass bulb does not contain mercury but contains main light emitting metal halide (NaI and ScI3). A rare gas is enclosed in the closed glass bulb with a charged pressure set to be in a range of from 8 to 20 atmospheres. If necessary, a predetermined buffer metal halide acting as a buffer substance is enclosed in the closed glass bulb. The charged pressure of the rare gas is higher than the conventional charged pressure (6 atmospheres).

Abstract: The invention is an arc tube for a discharge bulb in which both ends of a light emitting tube inserting electrode bars respectively are sealed and a closed space having the electrodes opposed to each other and filled with a light emitting substance together with a rare gas for starting is provided in the light emitting tube, the light emitting tube is constituted by translucent ceramics having an excellent heat resistance and durability which is formed almost cylindrically and a ratio d/L of an outside diameter d to a whole length L is set to range from 0.2 to 0.5, thereby reducing a size. Moreover, the parallel ray transmittance of the light emitting tube is set to be 20% or less and the whole ray transmittance of the light emitting tube 12 is set to be 85% or more. Consequently, the whole light emitting tube uniformly emits a light so that a bar-shaped light emitting section having neither a luminance unevenness nor a color unevenness is obtained.

Abstract: In a discharge bulb having an arc tube formed with pinch seal portions on both ends of a sealed glass bulb that is a light-emitting discharge section, infrared transmitting films for blocking visible light and transmitting infrared light are applied to at least the pinch seal portions of the arc tube to prevent visible light from exiting the pinch seal portions and to suppress generation of glare. Infrared light from the pinch seal portions can pass through the infrared transmitting films, which prevents accumulation of heat in the arc tube (pinch seal portions and sealed glass bulb), thereby preventing the temperature of the arc tube from increasing excessively.

Abstract: A discharge bulb including an arc tube 16 having a light-emitting tube portion 20a and shroud glass 18 surrounding the arc tube 16 in a tubular form. An inert gas and metal halides are sealed in a discharge space 24 inside the light-emitting tube portion 20a, which is mercury-free. Xenon gas is filled in an annular space 34 between the arc tube 16 and the shroud glass 18. Heat is restrained from being transmitted from the light-emitting tube portion 20a to the shroud glass 18 through the annular space 34. An increase in the heat loss and the temperature rise of the shroud glass 18 are restrained.

Abstract: A lamp unit for emitting near-infrared light by electric discharge, has: a hollow discharge tube; a cesium halide enclosed in the hollow of the discharge tube; a near-infrared penetration filter covering around the discharge tube. The cesium halide may include at least one of cesium iodide and cesium bromide. Also, an indium halide and thallium halide may further be enclosed in the hollow discharge tube.

Abstract: An arc tube and method for forming an arc tube in which an electrode assembly including a tungsten electrode and a molybdenum foil are joined together in a partially overlapped state and pinch sealed into a pinch seal portion of the arc tube body to suppress leakage due to peeling of the molybdenum foil and prolong the life period of the arc tube. An overlapped length L1 of a tungsten electrode and a molybdenum foil is set to be 2D≦L1≦0.8W with respect to the diameter D of the tungsten electrode and the width W of the molybdenum foil. In another embodiment, the distance L2 between the molybdenum foil and a discharge space is set to be B≦L2≦0.8A with respect to the width A and the thickness B of a pinch seal portion.

Abstract: A mercury-free arc tube includes a closed glass bulb held between pinch seal portions located at opposite ends of the close glass bulb; and a pair of electrodes provided in the closed glass bulb so as to be opposite to each other. The closed glass bulb does not contain mercury but contains main light emitting metal halide (NaI and ScI3). A rare gas is enclosed in the closed glass bulb with a charged pressure set to be in a range of from 8 to 20 atmospheres. If necessary, a predetermined buffer metal halide acting as a buffer substance is enclosed in the closed glass bulb. The charged pressure of the rare gas is higher than the conventional charged pressure (6 atmospheres).

Abstract: A discharge bulb comprising an arc tube body having such a structure that a shroud glass having metal oxide (Al2O3, CeO2) added thereto is attached integrally to surround an arc tube sealing Hg, NaI, ScI and Xe gases. A total amount of addition of the metal oxide in the shroud glass is set to be 4000 ppm or more which is effective for fulfilling an electrostatic shielding function for an external electric field and less than 7000 ppm which can hold the excellent molding property of the shroud glass.

Abstract: In a discharge lamp device, the arc tube body is configured by welding and integrating shroud glass with an arc tube so as to enclose a discharging portion, and a rearward elongating portion of the arc tube that elongates in the rear of the shroud glass is inserted and held into an opening of an insulating plug which is made of synthetic resin. A UV blocking film is formed on the outer surface of the rearward elongating portion of the arc tube. UV components of leakage light from the rearward elongating portion are cut off, and the amount of ultraviolet rays to which the resin layer in the opening is exposed is reduced. The UV blocking film is in the opening, and hence cannot be seen through a front lens.

Abstract: An arc tube and method for forming an arc tube in which an electrode assembly including a tungsten electrode and a molybdenum foil are joined together in a partially overlapped state and pinch sealed into a pinch seal portion of the arc tube body to suppress leakage due to peeling of the molybdenum foil and prolong the life period of the arc tube. An overlapped length L1 of a tungsten electrode 26 and a molybdenum foil 30 is set to be 2D≦L1≦0.8 W with respect to the diameter D of the tungsten electrode 26 and the width W of the molybdenum foil 30, whereby occurrence of peeling of the molybdenum foil 30 is effectively suppressed while effectively suppressing occurrence of breakage of the molybdenum foil 30. In another embodiment, the distance L2 between the molybdenum foil 30 and a discharge space 24 is set to be B≦L2≦0.