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: An electrodeless discharge lamp includes an induction coil that includes a core and a winding wound around the core and generates an electromagnetic filed inside a bulb, an insert portion provided inside the core, and a plane portion that releases heat from the insert portion to the outside of a case. A tolerance in the inductance of the induction coil is reduced by spacing the end portion of the core on the side of the plane portion apart from the plane portion, which makes reliable start-up possible.

Abstract: An object of the present invention is to provide an electrodeless discharge lamp whose discharge vessel will not fall off for long until the last stage of the lifespan of the lamp, and is capable of obtaining a uniform luminous performance throughout its luminous area by assuring a positioning accuracy of the discharge vessel and the induction coil thereof.

Abstract: An arc tube is a connected bulb composed of three U-shaped bulbs that are set annularly on a holder and connected by a bridge connector to include a serpentine discharge path. Electrodes are provided at both ends of the connected bulb. A reflector is set in a space enclosed by the three U-shaped bulbs, with a predetermined positional relation with the holder. The reflector has a reflecting part which reflects light emitted from the arc tube, and a fixing part positioned at the end of the reflecting part. The holder has an insertion hole which allows the reflecting part to pass through but not the fixing part. The reflector is mounted to the holder by inserting the reflecting part into the insertion hole from the side of the holder opposite to the arc tube, and passing the reflecting part through the insertion hole to the other side.

Abstract: A less costly bulb-shaped fluorescent lamp with improved assembly efficiency is provided which prevents the impairment of product quality due to the change in color of a holder or the slipping off of a fluorescent tube from the holder decreased in resin strength. The fluorescent lamp includes a set of fluorescent tubes, filament coils disposed at both ends of each fluorescent tube, a starter circuit for activating the fluorescent tubes, a holder for retaining the fluorescent tubes, and a case containing the starter circuit. The holder includes holes for receiving the fluorescent tubes, and a recess defined in a central portion of the holder and extended in the opposite direction of the fluorescent tubes.

Abstract: A bulb-type fluorescent lamp has a case having an open end portion for housing a lighting circuit therein, an arc tube extending outside through the open end portion of the case, and a globe having an open end portion for housing the arc tube therein. An adhesive is supplied to the inner surface of the open end portion of the case at four circumferentially spaced areas, and the open end portion of the globe is inserted into the open end portion of the case. As a result, the globe is fixed to the case with the adhesive.

Abstract: A self-ballasted electrodeless discharge lamp includes a discharge vessel having a cavity, an induction coil that is inserted into the cavity, a ballast for supplying power to the induction coil, a case for covering the ballast, and a lamp base provided in the case. The discharge vessel is secured to the case via a holder. A part of the discharge vessel and a first portion of the holder are engaged with each other to constitute a combination structure. A second portion of the holder and a part of the case are engaged with each other to constitute a combination structure.

Abstract: The present invention provides an inexpensive low-pressure mercury vapor discharge lamp having enhanced productivity. The low-pressure mercury vapor discharge lamp comprises an arc tube, a holder for holding the arc tube, a lighting circuit held on the opposite side of the holder from the arc tube and adapted for lighting the arc tube, a case having a screw portion provided at one end thereof and adapted for accommodating the lighting circuit, and a base threaded and fixed to the screw portion. A recessed groove is provided in a helical screw thread of the screw portion. The two lead wires (top lead wire and side lead wire) which are power source wires are respectively connected at one end thereof to the lighting circuit. The side lead wire is disposed along the groove and is sandwiched and fixed between the base and the screw portion.

Abstract: A fluorescent lamp in which a connecting terminals of a lighting circuit board and lead wires of a fluorescent tube easily can be connected. The lamp includes a fluorescent tube, a holder holding the fluorescent tube, a lighting circuit board provided with a lighting circuit for lighting the fluorescent tube, and a case connected to the holder and housing the lighting circuit board. At the end portion of the lighting circuit board, V-shaped or Y-shaped cut-outs, which widen toward an outer side, are formed. In the vicinity of the inner narrow portion of the cut-outs, the connecting terminals connected to the lighting circuit are provided. On a side wall formed on the holder opposite to the fluorescent tube, V-shaped or Y-shaped cut-outs, which widen as the distance from said fluorescent tube increases, are provided, and the broad portion of the cut-outs of the holder and the broad portion of the cut-outs of the lighting circuit board are arranged facing each other.

Abstract: A less costly bulb-shaped fluorescent lamp with improved assembly efficiency is provided which prevents the impairment of product quality due to the change in color of a holder or the slipping off of a fluorescent tube from the holder decreased in resin strength. The fluorescent lamp includes a set of fluorescent tubes, filament coils disposed at both ends of each fluorescent tube, a starter circuit for activating the fluorescent tubes, a holder for retaining the fluorescent tubes, and a case containing the starter circuit. The holder includes holes for receiving the fluorescent tubes, and a recess defined in a central portion of the holder and extended in the opposite direction of the fluorescent tubes.

Abstract: A less costly bulb-shaped fluorescent lamp with improved assembly efficiency is provided which prevents the impairment of product quality due to the change in color of a holder or the slipping off of a fluorescent tube from the holder decreased in resin strength. The fluorescent lamp includes a set of fluorescent tubes, filament coils disposed at both ends of each fluorescent tube, a starter circuit for activating the fluorescent tubes, a holder for retaining the fluorescent tubes, and a case containing the starter circuit. The holder includes holes for receiving the fluorescent tubes, and a recess defined in a central portion of the holder and extended in the opposite direction of the fluorescent tubes.

Abstract: A low pressure mercury vapor discharge lamp including a discharge tube filled with rare gas and mercury, a base provided at the both ends of the discharge tube and surrounding an electrode sealing portion, and a caulking terminal planted in the base and having a tip inside the base, wherein the base includes electric wiring and at least one of the electric wiring is connected to the caulking terminal to provide an electric connection inside the base. Thus, the position of the caulking terminal is fixed and the automation in the caulking connecting process is realized. Furthermore, after caulking connection, adhesives for adhering the caulking terminal to the inside of the base are not required, thus improving the operation property and productivity by reducing the number of steps and the material cost.

Abstract: An arc tube is a connected bulb composed of three U-shaped bulbs set annularly and connected by a bridge connector to include one discharge path. A reflector is set in a space enclosed by the three U-shaped bulbs, the bottom end of the reflector being fixed to a holder. The reflector has a conical part, and a cylindrical part whose height is greater than a height of a clearance between the pair of legs of each U-shaped bulb, and smaller than a height of the U-shaped bulb. At least within the height of the clearance between the pair of legs, a diameter of the reflector is greater than both a width of the clearance between the pair of legs and a width of each clearance between neighboring U-shaped bulbs, improving light distribution of the arc tube. A reflector may have a reflective body and a restrictive member integrally formed.

Abstract: A fluorescent lamp includes an end cap 4 and a fluorescent tube 1 that has electrode seals 22 and 23 at its ends. The end cap 4 is made of synthetic resin and is attached to the fluorescent tube 1 by silicon resin 31. The end cap 4 includes round cavities 26 and 27 for holding the electrode seals 22 and 23 and thermal protection element holders 20 and 21 for holding thermal protection elements 16 and 17 adjacent to the electrode seals 22 and 23. Pillars 28 are provided between the thermal protection element holders 20 and 21 and the round cavities 26 and 27 to support the thermal protection elements 16 and 17. Through holes 29 are provided between the round cavities 26 and 27 and pillars 28.

Abstract: A low pressure mercury vapor discharge lamp comprising a fluorescent tube having an amalgam container containing amalgam to control mercury vapor pressure at a steady lighting, a holder holding both ends of the fluorescent tube, a lighting circuit to light the fluorescent tube, a case accommodating the lighting circuit, and a base provided to the case, wherein the amalgam container and the base are connected with each other by a heat conductive component, so that the amalgam temperature is controlled at a proper value and the luminous efficiency is improved.

Abstract: An annulus fluorescent lamp comprises a plurality of annulus fluorescent tubes having different diameters and disposed substantially concentrically in substantially the same plane. Each of the annulus fluorescent tubes has a first end with electrodes and a second end without electrodes. The second ends of the annulus fluorescent tubes are communicated with each other via a bridge portion so that a single discharge path is formed inside the plurality of annulus fluorescent tubes. The annulus fluorescent lamp also comprises a mouthpiece covering the first and second ends of the annulus fluorescent tubes. The second end forms the lowest temperature portion. The mouthpiece is provided with through holes for ventilation close to the second end and an insulating wall on an inner face for separating power lines at the first ends from the through holes for ventilation.

Abstract: An annulus fluorescent lamp comprises two annulus fluorescent tubes formed into shapes having different diameters and disposed substantially concentrically in substantially the same plane. Each of the annulus fluorescent tubes has a first end with an electrode seal portion and a second end without electrodes. The second ends of the annulus fluorescent tubes are communicated with each other via a bridge portion so that a single discharge path is formed inside the plurality of annulus fluorescent tubes. The annulus fluorescent lamp also comprises a mouthpiece covering the first and second ends of the annulus fluorescent tubes, and a thermal fuse disposed in the mouthpiece and close to the electrode seal portion of the annulus fluorescent tubes. The thermal fuse is connected electrically between one of outer lead wires of the electrodes and one of lead terminals fixed to the mouthpiece.