Toshiba Lighting & Technology Corporation

Harison Toshiba Lighting Corporation

Hiromichi Kawashima

Kozo Uemura

Hiroyuki Kato

Makoto Deguchi

Mamoru Furuya

Seiko Kawashima

Kazuo Honda

Toshihiko Ishigami

Mikio Matsuda

Toshio Hiruta

Nobuhiro Tamura

Ichiro Tanaka

Hisashi Yoshida

Yasuki Mori

Masakazu Shibuya

Yasuhiro Iwafuji

Youichiro Mitsuyuki

Takuya Honma

Makoto Nishizawa

Sakae Katayama

Nanao Murase

Yoshiyuki Watanuki

Satoko Ishikawa

The present invention provides a high-pressure discharge lamp that uses substantially no mercury and reduces discharge flicker. The high-pressure discharge lamp is kept on with a lamp power of 50 W or lower in a stable state, and the temperature T (&#xb0; C.) of the electrode at a point at a distance of 0.3 mm from the tip end to the base end in the stable state and the amount A (mol/cc) of free iodine produced when the lamp is turned off after 100 hours of on-time satisfy the formula (1):T/A&#x3e;10.

High-pressure discharge lamp, high-pressure discharge lamp lighting device and automotive headlamp apparatus

A metal halide lamp comprises a refractory, light-transmitting airtight container defining therein a discharge space with an internal volume of not more than 0.1 cc, electrodes sealed in the container, opposing each other with a distance of not more than 5 mm interposed, and a discharge medium sealed in the container and including a metal halide material and a rare gas. The metal halide includes first and second halide materials. The first halide material contains scandium (Sc) and sodium (Na) halides. The second halide material contains at least one of indium (In) and zinc (Zn) halides. The discharge medium contains substantially no mercury. The load on the wall of the container in a stable state is 50 W/cmor more. A/B&#x2266;0.21 where A represents the intensity of an impurity chromium (Cr) spectrum in lighting spectra, and B represents the intensity of a scandium (Sc) spectrum.

Metal halide lamp and lighting device

A metal halide lamp includes a fire-resistant and translucent hermetic vessel containing amounts of scandium halide and sodium halide sealed in the hermetic vessel satisfying the formula of 0.25&#x3c;a/(a+b)&#x3c;0.5, where reference character 'a' denotes the mass of scandium halide and reference character 'b' denotes the mass of sodium halide.

Metal halide lamp and automotive headlamp apparatus

A metal halide lamp comprises a discharge container including a discharge space and a pair of sealing sections. A discharge medium containing a metal halide and a rare gas and essentially free from mercury is sealed in the discharge container. A pair of electrodes are arranged to face each other within the discharge space, and the side edge portions on the side of the proximal end portion of these electrodes are held by the sealing sections. The amount of water contained in the metal halide, i.e., the light-emitting material, included in the metal halide lamp essentially free from mercury, i.e., Hg-less metal halide lamp, is controlled to 50 ppm or less.

Metal halide lamp, headlight apparatus for vehicle using the same, and method of manufacturing metal halide lamp

To provide, in a special situation of a mercury-free lamp in which a luminance flicker tends to occur unlike a mercury-containing lamp, a metal halide lamp having an electrode structure modified so as to suppress the luminous flicker that is suitably used as an automotive headlamp, and an automotive headlamp apparatus incorporating the same. A metal halide lamp includes: a hermetic vesselwhich is fire resistant and translucent; a pair of electrodessealed in the hermetic vesselwith facing each other at a distant of 5 mm or less, the electrodes each having a shaft parthaving a diameter of 0.25 mm or more and a tip, which originates an arc, having a curved surface having a radius of one-half or less of the diameter of the shaft part; and a discharge medium essentially containing no mercury, sealed in the hermetic vessel, and containing halides of metals including a light-emitting metal in an amount of 0.005 mg/mmof an inner volume of the hermetic vessel or more and a xenon gas at 5 atmospheres or higher at a temperature of 25&#xb0; C., in which the metal halide lamp is turned on with a lamp power of 60 W or lower in a stable state.

Metal halide lamp with electrodes having a curved surface part and automotive headlamp apparatus

A high-pressure mercury discharge lamp comprises a light-transmitting discharge vessel having a region surrounding a discharge space and seal portion, a spaced apart electrodes disposed in the discharge vessel and defining a discharge path, and a filling contained in the discharge vessel including mercury, halogen and lithium (Li). Components of the filling are selected such that a ratio of relative spectral energies B/A is within a range 0.15 to 0.45; wherein A represents the relative spectral energy of mercury (Hg) within a wavelenth range of 402.5 nm to 407.5 nm, and B represents the rlative spectral energy of lithium (Li) within a wavelength range of 667.5 nm to 672.5 nm.

High-pressure mercury discharge lamp and lighting apparatus using the lamp

A cathode-side first sealed portion (,) and an anode-side first sealed portion (,) are respectively provided at the two opposing ends of a discharge space (,) of a discharge casing (,). A middle chamber (,) filled with a rare gas is provided adjacent to the anode-side first sealed portion (,). A second sealed portion (,) is provided adjacent to the middle chamber (,). Each sealed portion (,),(,),(,) is airtightly sealed by the pinch sealing method. A cathode (,) is welded to a metal foil conductor (,) disposed in the cathode-side first sealed portion (,). An anode (,) is welded to a metal foil conductor (,) disposed in the anode-side first sealed portion (,). The metal foil conductor (,) in the anode-side first sealed portion (,) and a metal foil conductor (,) in the second sealed portion (,) are connected to each other by means of a lead wire (,) passing through the middle chamber (,). A lead wire (,) that is drawn out of the lamp is welded to the metal foil conductor (,) in the second sealed portion (,). A sufficient distance from the discharge space (,), from which the heat is conducted, to the second sealed portion (,) exposed to the outside air can easily be ensured. Therefore, the invention is capable of ensuring the functioning of the high pressure discharge lamp (,) to the end of its life by protecting the welded portions of the lead wire (,) from deterioration, which may otherwise occur due to the exposure to the outside air at high temperature.

High-pressure discharge lamp, high-pressure discharge lamp apparatus, and light source

A DC glow discharge lamp is disclosed, in which one the pinch seal portions of an arc tube of quartz glass with an anode and a cathode arranged therein in opposed relation to each other is bonded to a base by means of a ceramic adhesive containing a binder, and a conductive member connected around the cathode-side pinch seal portion is mounted in such a manner as to assume the same potential as the cathode. Even in the case where the binder mixed in the ceramic adhesive for improving the bonding strength is vaporized, it attaches to the conductive member and assumes a negative potential and thus is prevented from attaching to the cathode-side pinch seal portion. The devitrification of the pinch seal portion or the leakage therefrom which otherwise might occur due to the binder are thus suppressed, thereby providing a DC glow discharge lamp with an improved service life.

DC glow discharge lamp, and ignition apparatus, flood-light apparatus

High intensity spotlight

A prescribed amount of tin halide is sealed in the arc tube of a metal halide lamp wherein a given amount of metal halide including a target amount of halogen and at least a predetermined amount of rare earth metal is sealed in the arc tube thereof to maintain a high lumen maintenance factor for an extended operation period. The prescribed amount of tin halide is preferably within 4.6.about.234 mol % of the predetermined amount of rare earth metal.

Growing community of inventors

Yokosuka, Japan

Hiromichi Kawashima