Abstract: A method and apparatus for forming an array of microcavities in the surface of a metal film uses an excimer laser or an ultrashort laser which to produce a beam of laser light pulses. An optical mask divides the beam into multiple beams and a lens system focuses the multiple beams onto the metal film. The device operates by generating multiple beams of laser pulses of a first diameter and then magnifying the pulses by a magnification factor less than 1 to produce multiple beams of pulses having a second diameter, less than the first diameter, which are applied to the metal film. The magnification factor and the intensity of the laser is such that the fluence of the laser on the optical mask is not sufficient to cause ablation while the fluence on the metal film is sufficient to cause ablation. A diffractive optical element may be used in the device in place of the optical mask. The apparatus includes a quarter wave plate that converts the beam of laser light pulses into a beam of circularly polarized pulses.

Abstract: A fluorescent lamp operating apparatus comprises a power switching element electrically connected to a fluorescent lamp having a pair of electrodes, and means for limiting the current flowing through the power switching element by controlling its conductance so as to prevent the power switching element from being broken by a large current flowing from the power line through the fluorescent lamp when the impedance between the pair electrodes decreases from infinity at the start-up of the fluorescent lamp.

Abstract: A high-pressure discharge lamp includes a glass housing made of a high-melting vitreous material, a pair of sealing components made of the same high-melting vitreous material and extended from the glass housing. A rare gas and a material that is solid or liquid at room temperature is sealed inside the glass housing. Electrically conductive bars are embedded in the sealing components. The air-tight seals around the electrically conductive bars are formed such that at least one metal material selected from metals and oxides of said metals is provided near the regions lying between the high-melting vitreous material and the electrically conductive bar.

Abstract: An image projector has a lamp unit 23 having a high-pressure mercury vapor discharge lamp 21 and a parabolic mirror 22. To the high-pressure mercury vapor discharge lamp 21, a driving system 24 applies an alternating voltage such that wandering of a cathode luminescent spot generated in the vicinity of a tip of each of the discharge electrodes of the high-pressure mercury vapor discharge lamp 21 is suppressed, the frequency being within the range of 20-42 kHz. This construction allows to prevent flicker in a projected image of a liquid crystal projector and the like, and therefore achieves high quality in the projected image.

Abstract: Disclosed is a dimmable fluorescent lamp operating apparatus which comprises a fluorescent lamp, electrical characteristic detecting element for detecting an electrical characteristic of the fluorescent lamp, an inverter circuit for driving the fluorescent lamp, and a feedback controlling circuit for controlling the drive frequency of the inverter circuit such that the electrical characteristic of the fluorescent lamp becomes a predetermined value, wherein the feedback controlling circuit includes temperature detecting element for detecting the temperature of the fluorescent lamp and wherein the frequency characteristic bandwidth of the feedback controlling circuit is varied based on the detected fluorescent lamp temperature.

Abstract: In a conventional electrodeless discharge lamp, a large amount of magnetic field leaks from at light-transparent envelope, and the efficiency of conversion from electric power to light energy is low. In a electrodeless discharge lamp in which light-emitting gases in a light-transparent envelope are excited with a magnetic field generated from a coil, end portions of a magnetic material included in the coil are substantially axially disposed in the light-transparent envelope. As a result, the magnetic flux which leaks outside the light-transparent envelope is decreased so the density of the magnetic flux in the envelope is increased and the efficiency of the lamp is improved.

Abstract: A discharge lamp includes a luminous bulb in which a luminous material is enclosed and a pair of electrodes are opposed in the luminous bulb; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. At least one of the pair of metal foils has a twist structure.

Abstract: A discharge lamp operating apparatus includes a discharge lamp; a dimmer for performing phase-control with respect to an input power source; and a ballast circuit for dimming and operating the discharge lamp in accordance with an AC voltage that is phase-controlled by the dimmer. A relationship Z2≦(Vin/Vob−1)×Z1 is satisfied, where Z1 (&OHgr;) is an impedance between an input terminal and an output terminal of the dimmer, Vob (V) is a breakover voltage of a bidirectional trigger diode that applies a trigger signal and is connected to a gate terminal of a switching element included in the dimmer, vin (V) is an effective voltage of a commercial power source, and Z2 (&OHgr;) is an input impedance between the input terminals of the ballast circuit.

Abstract: The present invention provides a long-life discharge lamp by removing the causes of lowering the service life of the discharge lamp owing to quartz glass constituting the discharge lamp and a gas sealed therein, and also provides a discharge lamp production method wherein the mixing of impurities affecting the service life of the discharge lamp is prevented. In the discharge lamp the content of hydrogen, oxygen and their compounds existing in the light-emitting portion is such that the maximum intensity of the light-emitting spectral intensities of the above impurities is {fraction (1/1000)} or less of the intensity of the main light-emitting spectrum of the noble gas when glow discharge occurs by supplying a current of 3 mA, and also the content of OH groups included in the quartz glass of the sealing portions is 5 ppm or less by weight.

Abstract: The induction coil core used for an induction coil of a discharge lamp, the discharge lamp including: a bulb containing discharge gas inside; and the induction coil for generating an electromagnetic field with a frequency in a range of 50 kHz to 1 MHz inclusive in the bulb. The core is made of a Mn—Zn polycrystalline ferrite and has a Curie temperature of 270° C. or more.

Abstract: A discharge lamp includes a luminous bulb in which a luminous material is enclosed and a pair of electrodes are opposed in the luminous bulb; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. At least one of the pair of sealing portions is provided with at least one constricted portion whose length in a thickness direction of the metal foil in the sealing portion is smaller than that of other portions in the sealing portion.

Abstract: A mercury-free high-intensity discharge lamp operating apparatus includes a horizontally operated high-intensity discharge lamp including an arc tube in which a luminous material is enclosed and a pair of electrodes are arranged in the arc tube; a ballast including an alternating current generation means for supplying alternating current to the pair of electrodes; and a magnetic field application means for applying in substantially vertical direction a magnetic field having a component that is substantially perpendicular to a straight line connecting heads of the pair of electrodes; wherein mercury is not included as the luminous material in the arc tube.

Abstract: A lamp unit includes a lamp provided with a mirror and a house for holding the lamp provided with a mirror. The lamp provided with a mirror includes a discharge lamp including a luminous bulb in which a luminous material is enclosed and a pair of electrodes are opposed to each other in the luminous bulb; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively; and a reflecting mirror for reflecting light emitted from the discharge lamp and having a front opening for emitting the reflected light. The lamp provided with a mirror is formed so as to have a non-airtight structure. The house includes a transmission window made of a material for transmitting light emitted from the front opening and positioned forward in the emission direction of the front opening of the reflecting mirror.

Abstract: A method for cleaning a translucent tube for a discharge lamp having a luminous bulb portion includes the steps of introducing a cleaning fluid from one end of the translucent tube; and allowing the cleaning fluid to flow while bringing the cleaning fluid in contact with at least an inner face of the luminous bulb portion of an inner face of the translucent tube, thereby removing impurities attached on the inner face of the luminous bulb portion.

Abstract: A short arc mercury lamp includes a luminous bulb enclosing at least mercury as a luminous material and a pair of electrodes opposed to each other; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. The electrode central axis of one of the pair of electrodes is dislocated from the electrode central axis of the other electrode. The shortest distance d (cm) between the head of one of the electrodes and the head of the other electrode is larger than the value of (6M/13.6&pgr;)⅓ when the total mass of the enclosed mercury is M (g).

Abstract: A method for producing a discharge lamp of the present invention includes the steps of: preparing a glass pipe for a discharge lamp having a luminous bulb portion and a side tube portion, and a single electrode assembly including an electrode structure portion that will be formed into a pair of electrodes of the discharge lamp; inserting the single electrode assembly into the glass pipe for a discharge lamp such that the electrode structure portion of the single electrode assembly is positioned in the luminous bulb portion of the glass pipe for a discharge lamp; forming a luminous bulb in which the electrode structure portion is arranged inside by attaching the side tube portion of the glass pipe for a discharge lamp to a part of the single electrode assembly; and forming a pair of electrodes in the luminous bulb by melting and cutting a part of the electrode structure portion selectively.

Abstract: A discharge lamp includes a luminous bulb in which a luminous material is enclosed and a pair of electrodes are opposed to each other in the luminous bulb; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. Each of the pair of metal foils has an external lead on a side opposite to a side electrically connected to a corresponding electrode of the pair of electrodes. At least one of the pair of sealing portions is provided with a reflective film on a surface of the sealing portion in a portion where a connection portion of the external lead and the metal foil is sealed. The reflective film contains a material having a reflectance larger than that of a material constituting the sealing portion.

Abstract: A discharge lamp includes a luminous bulb in which a luminous material is enclosed and a pair of electrodes are opposed to each other in the luminous bulb; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. The pair of metal foils have a pair of external leads on the side opposite to the side electrically connected to the pair of electrodes, respectively. At least one of the pair of external leads is joined to a lead wire for external connection that is to be electrically connected to an external circuit by the plastic flow of a caulking member.

Abstract: A lamp made of a tube having a light emission portion glass and a side tube portion glass that extends in the light emission portion glass. The lamp has a sealed electrode assembly having an electrical current supply line with one end portion connected to a metal foil. A first portion of the side tube portion where an electrical current supply line is located is heated and this portion is compressed by a first pressure. A second portion of the side tube portion where a metal foil is located is heated and this portion is compressed by a second pressure. The second pressure is made larger than the first pressure.

Abstract: A discharge lamp operating apparatus includes a discharge lamp and a driving circuit of the discharge lamp. The driving circuit can vary power to be supplied to the discharge lamp and has a function to turn off the discharge lamp at a supplied power value above a supplied power value at which unstable discharge occurs in the discharge lamp.