Abstract: A lamp includes an arc tube and a lighting unit for lighting the arc tube. The lighting unit includes a rectifier circuit, a smoothing circuit for partial smoothing, and an inverter circuit having a pair of switching elements. The smoothing circuit smoothes portions of the output voltage of the rectifier circuit below the first voltage value and outputs a voltage that falls between the first voltage value and the second voltage value. The discharge sustaining voltage of the arc tube is set to fall between the first and second values of the voltage Vdc output from the smoothing circuit.

Abstract: A lamp includes an arc tube and a lighting unit for lighting the arc tube. The lighting unit includes a rectifier circuit, a smoothing circuit for partial smoothing, and an inverter circuit having a pair of switching elements. The smoothing circuit smoothes portions of the output voltage of the rectifier circuit below the first voltage value and outputs a voltage that falls between the first voltage value and the second voltage value. The discharge sustaining voltage of the arc tube is set to fall between the first and second values of the voltage Vdc output from the smoothing circuit.

Abstract: A lamp includes an arc tube and a lighting unit for lighting the arc tube. The lighting unit includes a rectifier circuit, a smoothing circuit for partial smoothing, and an inverter circuit having a pair of switching elements. The smoothing circuit smoothes portions of the output voltage of the rectifier circuit below the first voltage value and outputs a voltage that falls between the first voltage value and the second voltage value. The discharge sustaining voltage of the arc tube is set to fall between the first and second values of the voltage Vdc output from the smoothing circuit.

Abstract: An arc tube is composed of an arc tube body that is formed by winding a straight glass tube. Two portions of the straight glass tube are spirally wound around an imaginary conical surface. The spiraled portions of the glass tube are sandwiched between a pair of movable fixed plates. The spiraled portions of the glass tube are heated to a temperature equal to or higher than a point at which the glass tube is deformable and yet lower than the softening point of the glass tube. The spiraled portions are flattened by the movable plate moving downwardly under its own weight.

Abstract: A base for attaching to at least one end of a glass tube (12) that has two air-tight sealed ends, the at least one end having a remaining exhaust tube (38) that extends in a tube axis X direction of the glass tube, the base comprising: a base body (46) that is in a shape of a bottomed tube including a tubular part (42) and a bottom part (44), and receives the at least one end; and a pair of base pins (48, 50) that have been disposed upright on the base body (46), wherein the base body (46) has a housing part (52) that has been disposed in a center of the bottom part (44) so as to project in the tube axis X direction, and houses at least part of the remaining exhaust tube (38), and the base pins (48, 50) have been disposed upright on the bottom part (44) in substantially parallel to the tube axis X direction such that the housing part (52) is located between the base pins (48, 50).

Abstract: Provided is a fluorescent lamp composed of a bulb and bases provided at base ends. The bulb includes (a) a circumferential wall whose inner surface is coated with a fluorescent layer and (b) end walls each partially composed of a stem to which an electrode is attached, the stem being plate-shaped. The bases are each provided covering a corresponding one of the stems such that at least part of each end wall other than the stem is exposed. An inner surface of each stem is positioned closer to a center of the bulb in a bulb axis direction than an imaginary plane containing a corresponding edge of the bulb is.

Abstract: A fluorescent lamp has a bulb, a phosphor layer and a base. The bulb has a tubular portion and an axially-opposed end portions to each of which a stem mount is welded. Each stem mount has an electrode. Each end portion has a ring-shaped end wall and a portion for welding the stem mount located radially inward from an inner edge of the end wall. The phosphor layer is formed on an inner surface of the tubular portion. The base is provided to cover the stem mount. The base, in outside diameter, is smaller than the bulb and larger than the stem mount such that the end wall of the bulb is exposed.

Abstract: It is possible to obtain electrodes 15 and 16 for a discharge lamp which are compact and have a large packing capacity for electron emitting material if an electrode for a discharge lamp is structured to include a quadruple coil 50 which is made by performing a first winding of a filament 41 to make a single coil 44, performing a secondary winding of the single coil 44 to make a double coil 46, performing a tertiary winding of the double coil 46 to make a triple coil 48 and performing a quaternary winding of the triple coil 48, and, in the quadruple coil 50, at least a hollow space 47? surrounded by the tertiary winding is structured to be packed with electron emitting material.

Abstract: A lamp including an arc tube and a holder is provided. The arc tube includes a pair of electrodes respectively at both tube ends, and forms, between the pair of electrodes, a discharge path which turns in a double spiral substantially on one plane. The holder holds the arc tube in a state of fixing the tube ends of the arc tube and at least one part of the arc tube between the tube ends.

Abstract: A hot cathode discharge lamp (20) includes a glass bulb (22) having a protective film (24) and a phosphor layer (26) laminated on an inner face thereof and having mercury (21) and a buffer rare gas mixture enclosed therein, and bead-mounted electrodes (30a, 30b). The hot cathode discharge lamp (20) is used as a light source in a backlight unit, in a 50° C. to 70° C. atmosphere. The buffer rare gas mixture includes krypton at a partial pressure rate of 20% or more.

Abstract: A low-pressure mercury discharge lamp includes: an arc tube made by winding a glass tube into double spiral configuration; a holding member that is in a form of a cylinder with a closed bottom and is for holding the arc tube; an electronic ballast for lighting the arc tube; a case in a cone form for covering the electronic ballast by being fit to a circumferential wall of the holding member; and a globe covering the arc tube. When an inner diameter of the arc tube is represented as Di mm, and tube wall loading of the arc tube is represented as L W/cm2, rectangular coordinates (Di, L) are confined within a range defined by points of: (2.5, 0.31), (4.0, 0.35), (5.5, 0.30), (6.5, 0.19), and (2.5, 0.01).

Abstract: An arc tube is formed by turning a glass tube at a substantially middle thereof and winding the glass tube from the middle to its both ends around an axis to form a double spiral, and sealing electrodes at both ends of the glass tube. The spiral pitch of a spiral part in a vicinity of one of the ends and an adjacent spiral part in the direction of the axis is set larger than the spiral pitch of other adjacent spiral parts, to widen a gap between the one end and the adjacent spiral part.

Abstract: Disclosed is a compact self-ballasted fluorescent lamp with higher luminous efficiency than conventional lamps and improved luminous flux rising characteristics at lamp startup equivalent to those of general fluorescent lamps. The compact self-ballasted fluorescent lamp (1) includes an arc tube (2) formed by a bent glass tube (9) covered with a globe (6). The glass tube (9) has a turning part substantially in the middle between its both ends, a first spiral part starting from one end and wound around an axis toward the turning part, and a second spiral part starting from the turning part and wound around the axis toward the other end. The arc tube (2) has mercury enclosed therein in a single form. The glass tube (9) has a substantially circular-shaped cross section and an inner diameter of 7.4 mm. The turning part is connected to the globe (9) via a heat-conductive member (15).

Abstract: An arc tube is composed of an arc tube body that is formed by winding a straight glass tube. Two portions of the straight glass tube are spirally wound around an imaginary conical surface. The spiraled portions of the glass tube are sandwiched between a pair of movable fixed plates. The spiraled portions of the glass tube are heated to a temperature equal to or higher than a point at which the glass tube is deformable and yet lower than the softening point of the glass tube. The spiraled portions are flattened by the movable plate moving downwardly under its own weight.

Abstract: A mandrel has a main body having a substantially-cone-shape. The main body has, on its circumferential surface, a spiral-shaped groove at which the glass tube to be wound is held. The groove, in cross section, has a contact range in which the glass tube's circumferential surface is in contact. One end of the contact range corresponds to a circumference part of the glass tube in wound state which is closest to the axis of the main body of the mandrel, a part of the groove that extends from the circumference part towards the apex of the main body is parallel to the axis of the mandrel, and the pitch of the groove in the axial direction of the mandrel is formed smaller than the outer diameter of the glass tube. The glass tube wound on the mandrel is easily removed from the main body by lowering the mandrel. In the arc tube formed in such a way, any two glass tube portions, which are adjacent to each other in the axial direction of the arc tube, overlap with each other.