Abstract: Disclosed is a high-pressure discharge lamp (100) that reduces the occurrence of cracks even under high mercury vapor pressure. The high-pressure discharge lamp (100) is provided with a glass arc tube (102) including a light-emitting part (103) and a sealing part (104) connected to the light-emitting part (103), the light-emitting part (103) enclosing a discharge space, and a pair of electrodes (101), one end of each of the electrodes (101) facing one end of the other electrode (101) in the discharge space, and another end of each electrode (101) being embedded in the sealing part (104) and connected to a metal foil (105), at least one embedded section of the pair of electrodes (101) including at least one projection (101c).

Abstract: A high-pressure discharge lamp having an arc tube with a casing made of glass. The arc tube includes a light-emitting part and sealing parts connected to the light-emitting part. A pair of electrode rods are disposed within the glass casing such that their tips face each other with a gap therebetween and project into the discharge space, and their base ends are embedded in the sealing parts and overlap surfaces of metal foils provided in the sealing parts. Each base end is coated with a coating foil made of metal and having a C-like cross section with a slit formed between edges thereof. An end of the coating foil farthest from the light-emitting part is located closer to the light-emitting part than an end of the metal foil closest to the light-emitting part.

Abstract: The projector uses two lamps, which are high-pressure discharge lamps with the same rated power, as light sources. The projector includes: a first alternating-current generator configured to generate a lamp current to be supplied to one of the lamps, based on an input control signal; a second alternating-current generator configured to generate a lamp current to be supplied to the other lamp, based on an input control signal; and a controller configured to control the lamp currents to have a same period and to be out of phase, by inputting a control signal to each of the first and the second alternating-current generators.

Abstract: The present invention aims to prevent breakage of a sealing part and an electrode of a high pressure discharge lamp, and provides an electrode 100 used for a discharge lamp and having a rod-shaped part 101, one end of the rod-shaped part 101 to be sealed by a sealing part of an arc tube of the discharge lamp, the other end of the rod-shaped part 101 to be in a discharge space in the arc tube, wherein the rod-shaped part 101 has a rough surface that is composed of a plurality of types of crystal grains each having a different surface condition due to differences in crystal orientation.

Abstract: A high-pressure discharge lamp comprising an arc tube, the arc tube including: a light-emitting part which is substantially ellipsoidal; and sealing parts which extend from either end of the light-emitting part and in which bases of electrodes are sealed, the arc tube enclosing 0.2 mg/mm3 to 0.4 mg/mm3 of mercury, the high-pressure discharge lamp having a power rating greater than 355 W and not greater than 600 W, wherein 5.4?D?5.8 and 3.1?X?D?2.3 when 355<P?380, 5.8?D?6.2 and 3.1?X?D?2.7 when 380<P?450, and 6.2?D?6.6 and 3.1?X?D?3.3 when 450<P?600, where P denotes the power rating in watts of the high-pressure discharge lamp, D denotes an inside diameter in millimeters of the light-emitting part 104 with reference to a midpoint between the electrodes 101, and X denotes a wall thickness in millimeters of the light-emitting part 104 with reference to the midpoint between the electrodes 101.

Abstract: A high-pressure discharge lamp having an electrode including an electrode rod, a melted part and a coil part, and satisfying 0 < La L < 0.3 , where La denotes an average value of a length in units of mm of an exposed portion of the coil part in an axial direction of the electrode rod, the exposed portion being not covered with the melted part, and L denotes a maximum value of a length in units of mm between a tip of a head of the electrode rod and an opposite edge of the coil part to the melted part, measured in the axial direction.

Abstract: A high-pressure discharge lamp having an electrode including an electrode rod, a melted part and a coil part, and satisfying 0 < La L < 0.3 , where La denotes an average value of a length in units of mm of an exposed portion of the coil part in an axial direction of the electrode rod, the exposed portion being not covered with the melted part, and L denotes a maximum value of a length in units of mm between a tip of a head of the electrode rod and an opposite edge of the coil part to the melted part, measured in the axial direction.

Abstract: A high-pressure discharge lamp having an arc tube with a casing made of glass. The arc tube includes a light-emitting part and sealing parts connected to the light-emitting part. A pair of electrode rods are disposed within the glass casing such that their tips face each other with a gap therebetween and project into the discharge space, and their base ends are embedded in the sealing parts and overlap surfaces of metal foils provided in the sealing parts. Each base end is coated with a coating foil made of metal and having a C-like cross section with a slit formed between edges thereof. An end of the coating foil farthest from the light-emitting part is located closer to the light-emitting part than an end of the metal foil closest to the light-emitting part.

Abstract: A high-pressure discharge lamp comprising an arc tube, the arc tube including: a light-emitting part which is substantially ellipsoidal; and sealing parts which extend from either end of the light-emitting part and in which bases of electrodes are sealed, the arc tube enclosing 0.2 mg/mm3 to 0.4 mg/mm3 of mercury, the high-pressure discharge lamp having a power rating greater than 355 W and not greater than 600 W, wherein 5.4?D?5.8 and 3.1?x?D?2.3 when 355?P?380, 5.8?D?6.2 and 3.1?x?D?2.7 when 380?P?450, and 6.2?D?6.6 and 3.1?x?D?3.3 when 450?P?600, where P denotes the power rating in watts of the high-pressure discharge lamp, D denotes an inside diameter in millimeters of the light-emitting part 104 with reference to a midpoint between the electrodes 101, and X denotes a wall thickness in millimeters of the light-emitting part 104 with reference to the midpoint between the electrodes 101.

Abstract: A short arc high-pressure discharge lamp has an arc tube 1 made of quartz glass including a light-emitting portion 2 that fills mercury inside thereof and has a pair of electrodes arranged so as to face each other, and a sealing portion 3 connected to the light-emitting portion. The pair of electrodes have an electrode bar 5a, one end of the electrode bar is located in an internal space of the light-emitting portion, and the other end of the electrode bar is embedded in the sealing portion and bonded to a conductive metal-foil 7 sealed in the sealing portion. In at least a part of a portion of the electrode bar embedded in the sealing portion, the entire outer peripheral surface thereof is covered tightly with a metal-foil sleeve 7a.

Abstract: The present invention is directed to a method for manufacturing a high-pressure discharge lamp including: a spherical portion forming a light-emitting portion (1a); sealing portions that are connected with both ends of the spherical portion; an electrode (2a) that is sealed to each of the sealing portions; and a metal foil (3a) that is connected with a rear end of each electrode. A vessel provided with a cylindrical glass tube (8) on both ends of the spherical portion is used, a connection structure of the metal foil and the electrode are disposed in the glass tube such that a front end of the electrode is positioned in the spherical portion, and the glass tube is melted by heat and shrunk for sealing the metal foil and the electrode so as to form the sealing portion. An inner diameter ? of the glass tube before the heat-melt processing and a distance L from an edge of the metal foil to the internal space of the spherical portion are set to satisfy a relationship of L/??1.

Abstract: Disclosed is a high-pressure discharge lamp (100) that reduces the occurrence of cracks even under high mercury vapor pressure. The high-pressure discharge lamp (100) is provided with a glass arc tube (102) including a light-emitting part (103) and a sealing part (104) connected to the light-emitting part (103), the light-emitting part (103) enclosing a discharge space, and a pair of electrodes (101), one end of each of the electrodes (101) facing one end of the other electrode (101) in the discharge space, and another end of each electrode (101) being embedded in the sealing part (104) and connected to a metal foil (105), at least one embedded section of the pair of electrodes (101) including at least one projection (101c).

Abstract: The present invention aims to prevent breakage of a sealing part and an electrode of a high pressure discharge lamp, and provides an electrode 100 used for a discharge lamp and having a rod-shaped part 101, one end of the rod-shaped part 101 to be sealed by a sealing part of an arc tube of the discharge lamp, the other end of the rod-shaped part 101 to be in a discharge space in the arc tube, wherein the rod-shaped part 101 has a rough surface that is composed of a plurality of types of crystal grains each having a different surface condition due to differences in crystal orientation.

Abstract: The projector uses two lamps, which are high-pressure discharge lamps with the same rated power, as light sources. The projector includes: a first alternating-current generator configured to generate a lamp current to be supplied to one of the lamps, based on an input control signal; a second alternating-current generator configured to generate a lamp current to be supplied to the other lamp, based on an input control signal; and a controller configured to control the lamp currents to have a same period and to be out of phase, by inputting a control signal to each of the first and the second alternating-current generators.

Abstract: A manufacturing method of a high-pressure mercury lamp includes an electric field application step in which an electric field is applied to at least a light emission part (4) with the high-pressure mercury lamp being kept at a high temperature. This can reduce impurities such as hydrogen and alkali metals in a discharge space (8) and glass forming the light emission part (4). As a consequence, blackening and devitrification of the high-pressure mercury lamp while the lamp is lit can be reduced.

Abstract: A long-life high-pressure discharge lamp can (i) suppress damage to sealing portions, especially at an initial stage of the accumulated lighting time, (ii) allow for easy assembly of components such as electrodes and (iii) prevent deformation/ripping of metallic foils. An arc tube is a glass enveloping vessel with electrodes arranged therein, and includes: a light emitting portion in which materials are enclosed and a discharge space is formed; and sealing portions provided at ends of the light emitting portion. Each electrode includes an electrode bar whose first end is in the discharge space, and whose second end is in the corresponding sealing portion and connected to a metallic foil. The second end of each electrode bar is partially wrapped around by a sleeve-like metallic cover foil that has a cut-out section positioned over a joining area where the second end of each electrode bar is joined to the metallic foil.

Abstract: The present invention is directed to a method for manufacturing a high-pressure discharge lamp including: a spherical portion forming a light-emitting portion (1a); sealing portions that are connected with both ends of the spherical portion; an electrode (2a) that is sealed to each of the sealing portions; and a metal foil (3a) that is connected with a rear end of each electrode. A vessel provided with a cylindrical glass tube (8) on both ends of the spherical portion is used, a connection structure of the metal foil and the electrode are disposed in the glass tube such that a front end of the electrode is positioned in the spherical portion, and the glass tube is melted by heat and shrunk for sealing the metal foil and the electrode so as to form the sealing portion. An inner diameter ? of the glass tube before the heat-melt processing and a distance L from an edge of the metal foil to the internal space of the spherical portion are set to satisfy a relationship of L/??1.

Abstract: A short arc high-pressure discharge lamp has an arc tube 1 made of quartz glass including a light-emitting portion 2 that fills mercury inside thereof and has a pair of electrodes arranged so as to face each other, and a sealing portion 3 connected to the light-emitting portion. The pair of electrodes have an electrode bar 5a, one end of the electrode bar is located in an internal space of the light-emitting portion, and the other end of the electrode bar is embedded in the sealing portion and bonded to a conductive metal-foil 7 sealed in the sealing portion. In at least a part of a portion of the electrode bar embedded in the sealing portion, the entire outer peripheral surface thereof is covered tightly with a metal-foil sleeve 7a.

Abstract: An image display device accurately evaluates the possibility of problems occurring due to the state of impure gas inside a discharge envelope in a high pressure discharge lamp. The image display device includes the high voltage discharge lamp and an evaluation unit (51) for evaluating the possibility of problems occurring due to the state of impure gas. The evaluation unit (51) includes a high voltage pulse generator (57) that generates a high voltage pulse for breaking insulation in the high pressure lamp, a constant current generator (58) that generates a constant current for illuminating the high pressure discharge lamp in a glow discharge state, a lamp voltage measurer (59) that measures lamp voltage during illumination in the glow discharge state, an LED (63), and a controller (65).

Abstract: A long-life high-pressure discharge lamp can (i) suppress damage to sealing portions, especially at an initial stage of the accumulated lighting time, (ii) allow for easy assembly of components such as electrodes and (iii) prevent deformation/ripping of metallic foils. An arc tube is a glass enveloping vessel with electrodes arranged therein, and includes: a light emitting portion in which materials are enclosed and a discharge space is formed; and sealing portions provided at ends of the light emitting portion. Each electrode includes an electrode bar whose first end is in the discharge space, and whose second end is in the corresponding sealing portion and connected to a metallic foil. The second end of each electrode bar is partially wrapped around by a sleeve-like metallic cover foil that has a cut-out section positioned over a joining area where the second end of each electrode bar is joined to the metallic foil.