Abstract: A high pressure discharge lamp of the present invention is provided with a light-emitting bulb comprising a light-emitting part and sealing sections; metal foils embedded within the sealing sections; and a pair of electrodes having one end protruding into the light-emitting part and having the other end embedded in the corresponding sealing section and joined to the corresponding metal foil. An embedded length L (mm) of the electrodes that is defined by the length between a light-emitting part side end of the metal foil and the border section between the protruding section and the embedded section of the electrode, and the temperature T (° C.) at the joint region of the electrode and the metal foil are set to satisfy 1.8?L?2.8 and T?970.

Abstract: The present invention is to provide a novel ultraviolet irradiation metal halide lamp which can produce more intense light of ultraviolet region with a wavelength near 365 [nm]. This lamp is a metal halide lamp to produce mainly light of ultraviolet region. In order to produce light with a high spectrum in ultraviolet region, particularly, light of a wavelength of 350 to 380 [nm], at least mercury (Hg) and an iron are sealed into this lamp together with a rare gas. The sealed iron into the lamp is supplied by iron iodide (FeI2) and iron bromide (FeBr2) as iron halide (FeX2) and metal iron (Fe). When a quantity of materials sealed into the lamp is expressed such that A represents a quantity of metal iron sealed into the lamp, B represents a quantity of iron iodide sealed into the lamp and C represents a quantity of iron bromide sealed into the lamp, respectively, the quantity A of the metal iron falls within the range of 0.5(B+C)?A?10.

Abstract: It is an object of the present invention to provide a metal halide lamp in which arc discharge in the initial stage of lamp lighting can be stabilized. A metal halide lamp includes a translucent outer tube with a base formed at one end thereof and a light-emitting portion disposed in the outer tube. This metal halide lamp is configured as a vertical mounting type such that the base thereof looks toward the upper side. The discharge tube has mercury and metal halides enclosed therein. Assuming that a lamp rated power is P [W], then a mercury concentration d(Hg) [?mol/cm3] in the discharge tube falls within a range of values of ±10% of a mercury concentration d(Hg) obtained by the following equation. “d(Hg)=0.0007P2?0.4113P+99.

Abstract: The present invention aims to suppress waste of charging power during charging and improve charging efficiency.

Abstract: A ceramic metal halide lamp is provided in which color rendering properties, especially a special color rendering index R9, are improved without causing lamp efficiency to be lowered substantially. In one aspect, a ceramic metal halide lamp includes a luminous tube in the interior of an outer bulb. The luminous tube is made from translucent ceramics and includes a light-emitting portion into which metal halides, mercury and a starting gas are sealed and capillaries with a pair of electrode assemblies extended thereto disposed at both ends of the light-emitting portion. The light-emitting portion has sealed therein at least thulium iodide (TmI3), thallium iodide (TlI), sodium iodide (NaI) and calcium iodide (CaI2). The light-emitting portion has further sealed therein silver iodide (AgI). A quantity of the AgI falls within a range of 2?(AgI/CaI2)[molar ratio]?5 and within a range of 0<(AgI/TlI)[molar ratio]?10.

Abstract: The high pressure discharge lamp ballast drives a high pressure discharge lamp with a synthesized-waveform alternating current made of multiple frequency components, the high pressure discharge lamp having a pair of electrodes disposed to face each other. The ballast controls a ratio of the multiple frequency components per unit time; applies a synthesized-waveform current in accordance with the ratio to the high pressure discharge lamp; and detects a lamp parameter of the high pressure discharge lamp. The control circuit is configured to shift the ratio to a first ratio when the lamp parameter is in a first state, and shifts the ratio to a second ratio when the lamp parameter is in a second state. The control circuit changes the ratio stepwise when the ratio is shifted from the first ratio to the second ratio, or when the ratio is shifted from the second ratio to the first ratio.

Abstract: A light utilization efficiency of a high-pressure discharge lamp is improved even in a case of reducing the size of a reflection mirror without using an auxiliary reflection mirror. In a lamp device where a portion of lights emitted from a discharge bulb to the periphery thereof in forward and backward directions for a predetermined range of angle is reflected at a concave reflection mirror and illuminated to a light collection area of a predetermined size formed forward of the lamp, a prism surface having an angle of refracting or deflecting at least a portion of lights emitted from the discharge bulb that is not reflected at the concave reflection mirror to the light collection area is formed to the outer peripheral surface of the discharge bulb.

Abstract: Starting performance is improved by efficient UV-light irradiation, suppressing creeping discharge or atmospheric discharge at the outside of a glow discharge tube, and preventing cracks in a pinch seal portion even when an external force is exerted in the direction of bending a lead. In a discharge tube for emitting a UV-light, a light emitting chamber is formed on one side of a pinch seal portion for sealing an electrode assembly, and a lead protrusion port is formed on the opposite side thereof while pinching the seal portion, the lead protrusion port is formed as a sleeve having a predetermined gap relative to the lead, an external electrode disposed to the outside of the light emitting chamber includes a hold formed by bending fabrication of a metal plate.

Abstract: A high pressure discharge lamp ballast performs driving with a synthesized current waveform comprising a combination of first and second sets of current waveforms. The ballast controls content rates of each of the sets per unit time; detects a rotation synchronization signal for a color wheel; applies a synthesized current waveform in accordance with the synchronization signal and the content rates to a high pressure discharge lamp; and detects a lamp voltage. A period of each of the first and second sets equals to one rotation of the color wheel. The number of inversions of the second set is larger than that of the first set. The content rate of the second set is set to RL% when the lamp voltage exceeds a value V, and the content rate of the second set is set to RH% when lamp voltage falls below a value V?.

Abstract: A high pressure discharge lamp of the present invention is provided with a light-emitting bulb comprising a light-emitting part and sealing sections; metal foils embedded within the sealing sections; and a pair of electrodes having one end protruding into the light-emitting part and having the other end embedded in the corresponding sealing section and joined to the corresponding metal foil. An embedded length L (mm) of the electrodes that is defined by the length between a light-emitting part side end of the metal foil and the border section between the protruding section and the embedded section of the electrode, and the temperature T (° C.) at the joint region of the electrode and the metal foil are set to satisfy 1.8?2.8 and T?970.

Abstract: one spectrum correction filter that changes a spectral characteristic of emission light from the light source, at least one neutral density filter disposed on the same optical axis of the spectrum correction filter, wherein the at least one spectrum correction filter and/or the at least one neutral density filter is tilted so that a travel direction of reflection light reflected from the at least one spectrum correction filter is deviated from the optical axis.

Abstract: A manufacturing method of a ceramic metal halide lamp is provided where electrical characteristics and optical characteristics changed at the first time when the lamp begins to glow can be decreased. An example lamp includes a luminous tube with silver iodide (AgI) enclosed therein with predetermined amounts of mercury, metal halides and rare gas. Luminous flux change is measured by changing AgI/total amount of metal halide (weight ratio). An upper limit of AgI is determined by specifying an upper limit value of AgI/total amount of metal halide (weight ratio) based on an allowable lowering rate of luminous flux. Lamp voltage change is measured by changing AgI/total amount of metal halide. A lower limit of AgI is determined by specifying the AgI/total amount of metal halide based on an allowable lowering rate of lamp voltage. An AgI amount falling between the upper and lower limits is sealed into the luminous tube.

Abstract: The present invention relates to a lamp having a spacer which is made of a thin metal plate being put on a closed end of an inner tube and held between the inner tube and the outer tube for keeping a predetermined constant distance therebetween for coaxially arranging the inner tube and the outer tube. In order to reduce the deepness of the shadow caused by strips of the spacer that shield light emitting through the inner tube, the spacer is attached to an exhaust portion protruding from a center of the closed end of the inner tube by inserting the exhaust portion into a hole, and strips, - - - extending in the direction of the opening end of the inner tube from peripheral edge of the center plate are inclined in a circumferential direction around an optical axis of the lamp.

Abstract: The high pressure discharge lamp ballast of the present invention includes: power supply means for supplying an AC current to a lamp; and control means for cyclically changing a current value of the AC current to be supplied and a time interval between polarity inversions.

Abstract: High color rendition (Ra?80) and high efficiency (??100 (1 m/W)) which are effects conflicting to each other in a metal halide lamp are attained. An arc tube formed of translucent ceramics, capillaries are formed continuously on the both ends of an arc chamber formed substantially in an ellipsoidal shape in the direction of the longitudinal axis by way of a transition curve with no angled corner, and the arc tube is designed to effective length L/effective inner diameter D of 1.8 to 2.2, and formed to such a size that the lowest temperature of the arc chamber is 800° C. or higher and the highest temperature of the arc chamber is 1200° C. or lower during lighting, and at least thulium iodide, thallium iodide, sodium iodide, and calcium iodide are sealed as metal halides where sodium iodide and calcium iodide are sealed by a molar ratio of 40 to 80% and less than 30%, respectively, based on the entire metal halides.

Abstract: It is intended to enable accurate positioning of an electrode top end such that the arc length is constant and prevent leakage from sealing portions due to bending or twisting of a molybdenum foil upon sealing an electrode mount by heating the sealing portion. For attaining the object described above, a quartz bulb in which extension tubes each having an inner diameter larger than the inner diameter of the opening of a body tube is welded the openings of both ends of a body tube formed with light emitting portion and a sealing portion thereby forming to a positioning step is used, and electrode mounts each formed with a positioning engagement portion at a position spaced apart by a predetermined length from the electrode top end are inserted to engage the positioning engagement portion of the electrode mounts to the positioning step and, in this state, the sealing portions are sealed.

Abstract: Disclosed is an arrangement for a cut type electrode, wherein the removal of a coil is prevented and the generation of gap between turns of a coil caused by repeatedly turning on and off of the lamp is suppressed. The electrode, which is for a discharge lamp, comprises: a core rod having a leading end portion for discharge formed by a cutting process; and a coil wound around the core rod in n-turns in a state exposing the leading end portion, wherein at least a first portion between a first turn and a turn adjacent to the first turn and a second portion between an n-th turn and a turn adjacent to the n-th turn are welded.

Abstract: A xenon lamp drive unit of the present invention comprises: a charging circuit; and a current control circuit adapted to supply a current to a xenon lamp by using a charged voltage of the charging circuit as a power source, wherein the current control circuit is adapted to supply, in a first period after a lamp ignition, a high output lamp current having a higher current value than a steady output lamp current to the xenon lamp by constant current control and supply, in a second period after the first period, the steady output lamp current to the xenon lamp by constant current control.

Abstract: To prevent bending of an electrode shaft portion by a method which requires minimum increase in production cost, in an electrode mount for a high pressure discharge lamp. A manufacturing method of an electrode mount for the high pressure discharge lamp includes: a process of subjecting the electrode mount to a heat treatment, the electrode mount including an electrode and a metal foil which are welded to each other; and an oxidation process of producing an oxide on a surface of the electrode shaft portion of the electrode by laser irradiation to form an oxidation portion on the surface, wherein a laser irradiation position is determined such that a whole or part of the oxidation portion is included in a sealing portion of the high pressure discharge lamp when the electrode mount is embedded in the sealing portion.

Abstract: The present invention aims to reliably prevent overcharge by carrying out charging in just proportion during charging periods. A charging apparatus 1 for charging a secondary cell 22 by supplying a charging current Ic thereto is provided with a discharge amount detector 62 for detecting an amount of power discharged from the secondary cell in a non-charging state, a charge amount detector 60 for detecting an amount of power charged into the secondary cell in a charging state, and a charger controller 10 for stopping charging when the amount of charged power (charge amount Wc) becomes equal to the amount of discharged power (discharge amount Wc) during a charging period.