Abstract: A discharge lamp lighting device can reduce a variation in luminous flux at the time when the polarity of a voltage to be applied to the discharge lamp is inverted, prevent an excessively large amount of current from flowing through the discharge lamp at the time of starting, prevent the fade-out of discharge when the discharge mode returns from an arc discharge mode to a glow discharge mode, and reduce the ripple of a lamp current in a normal lighting mode. A coil is provided in an output current path of a power supply circuit comprising, for example, a step-down chopper, and a smoothing capacitor is provided in the next stage of the coil so that it selectively is turned on or off by a switching element. An inverter comprising, for example, a full bridge is provided in the next stage of the smoothing capacitor.

Abstract: To shorten the luminous flux rise time and prevent melting/deformation of the projections in the initial ignition period of high pressure discharge lamps that have a sealed mercury volume of no less than 0.20 mg/mm3, a power supply device feeds a current that exceeds the maximum current value of the constant power control period to the high pressure discharge lamp during a first control period from the initial discharge until the lamp voltage reaches a specified lamp voltage and causes a switch to constant power control, and then, during the following period until a change to steady power control, the power supply device feeds it a current that is less than the maximum current during regular operation.

Abstract: A discharge lamp lighting device can reduce a variation in luminous flux at the time when the polarity of a voltage to be applied to the discharge lamp is inverted, prevent an excessively large amount of current from flowing through the discharge lamp at the time of starting, prevent the fade-out of discharge when the discharge mode returns from an arc discharge mode to a glow discharge mode, and reduce the ripple of a lamp current in a normal lighting mode. A coil is provided in an output current path of a power supply circuit comprising, for example, a step-down chopper, and a smoothing capacitor is provided in the next stage of the coil so that it selectively is turned on or off by a switching element. An inverter comprising, for example, a full bridge is provided in the next stage of the smoothing capacitor.

Abstract: To shorten the luminous flux rise time and prevent melting/deformation of the projections in the initial ignition period of high pressure discharge lamps that have a sealed mercury volume of no less than 0.20 mg/mm3, a power supply device feeds a current that exceeds the maximum current value of the constant power control period to the high pressure discharge lamp during a first control period from the initial discharge until the lamp voltage reaches a specified lamp voltage and causes a switch to constant power control, and then, during the following period until a change to steady power control, the power supply device feeds it a current that is less than the maximum current during regular operation.

Abstract: A resonant transformer is disposed at a stage following an inverter for inverting the polarity of a voltage applied to a discharge lamp. A parallel resonant circuit is formed by a resonant capacitor and a primary winding of the resonant transformer, and a periodic voltage applying section is connected to the parallel resonant circuit. The periodic voltage applying section is operated at a frequency that causes resonance in the parallel resonant circuit, thereby applying a high AC voltage to the discharge lamp in a period in which discharge is started in the discharge lamp.

Abstract: A resonant transformer is disposed at a stage following an inverter for inverting the polarity of a voltage applied to a discharge lamp. A parallel resonant circuit is formed by a resonant capacitor and a primary winding of the resonant transformer, and a periodic voltage applying section is connected to the parallel resonant circuit. The periodic voltage applying section is operated at a frequency that causes resonance in the parallel resonant circuit, thereby applying a high AC voltage to the discharge lamp in a period in which discharge is started in the discharge lamp.

Abstract: A lamp lighting apparatus has a discharge drive circuit for supplying discharge current to the lamp, a voltage conversion circuit for boosting voltage from DC power and supplying the boosted voltage to the discharge drive circuit, and an arc discharge detecting circuit for detecting that a state of discharge of the lamp changes to arc discharge, and outputting an arc discharge transition signal to the voltage conversion circuit, wherein when the voltage conversion circuit receives the arc discharge transition signal which shows that the transition to the arc discharge does not take place, the voltage conversion circuit supplies a first voltage or higher to the discharge drive circuit, and when the voltage conversion circuit receives the arc discharge transition signal which shows that the transition to the arc discharge takes place, the voltage conversion circuit supplies a second voltage lower than the first voltage to the discharge drive circuit.

Abstract: A lamp lighting apparatus has a discharge drive circuit for supplying discharge current to the lamp, a voltage conversion circuit for boosting voltage from DC power and supplying the boosted voltage to the discharge drive circuit, and an arc discharge detecting circuit for detecting that a state of discharge of the lamp changes to arc discharge, and outputting an arc discharge transition signal to the voltage conversion circuit, wherein when the voltage conversion circuit receives the arc discharge transition signal which shows that the transition to the arc discharge does not take place, the voltage conversion circuit supplies a first voltage or higher to the discharge drive circuit, and when the voltage conversion circuit receives the arc discharge transition signal which shows that the transition to the arc discharge takes place, the voltage conversion circuit supplies a second voltage lower than the first voltage to the discharge drive circuit.

Abstract: A discharge lamp which eliminates the large line noise that forms in discharge lamps during startup while preventing heat loss in the transformer by providing a pair of opposed electrodes for the main discharge and an auxiliary electrode arranged such that it does not come into contact with the discharge space for the main discharge, a feed circuit for supplying the discharge current to the electrodes for the main discharge, and a starter circuit which produces a high voltage between one of the electrodes for the main discharge and the auxiliary electrode. The high voltage generating part of the starter circuit which includes at least a high voltage transformer that is separated from the feed circuit while the discharge lamp and the high voltage generating part are formed as an integral unit.

Abstract: The restart properties of a light source even under the condition of a hot restart is improved, and suppression of the danger of an insulation breakdown in an unintended area is achieved by a light source comprising a discharge lamp in which a pair of main discharge electrodes are located opposite a discharge space; an auxiliary electrode arranged such that it does not come into contact with the discharge space; a feed circuit that supplies a discharge current to the main discharge electrodes; and a starter that produces a high voltage between one of the main discharge electrodes and the auxiliary electrode, wherein, during a time interval during which the starter produces said high voltage, a high voltage is also applied to the main discharge electrodes at least during a portion of the time interval.

Abstract: To provide a high-pressure mercury lamp capable of shortening the light output rise time and of preventing glow discharge that occurs when the lamp is lighted, a high-pressure mercury lamp (1) luminescent device with a pair of electrodes (6, 7) placed opposite one another within a discharge vessel (2) made of quartz glass with seals (4, 5) formed on both ends and at least 0.15 mg/mm3 of mercury sealed into the discharge vessel, has a device (11, 12) for increasing the temperature of the outer wall of the luminescent portion (3) of the discharge vessel (2) to at least 100° C. before the high-pressure mercury lamp is lit.

Abstract: Light source device which includes a discharge lamp which contains at least 0.15 mg mercury per cubic millimeter of the volume of the discharge space, a pair of electrodes opposite one another to create the main discharge and spaced a distance from one another of less than or equal to 2.5 mm, and an auxiliary electrode arranged such that it does not come into contact with the discharge space for the main discharge. The light source device further including a feed circuit to feed the discharge current to the electrodes for the main discharge, and a starter which produces a high voltage between one of the electrodes of the two electrodes for the main discharge and the auxiliary discharge, such that the starter produces a voltage two to five times as high as the voltage necessary for starting the main discharge in the lamp at the room temperature state.

Abstract: The restart properties of a light source even under the condition of a hot restart is improved, and suppression of the danger of an insulation breakdown in an unintended area is achieved by a light source comprising a discharge lamp in which a pair of main discharge electrodes are located opposite a discharge space; an auxiliary electrode arranged such that it does not come into contact with the discharge space; a feed circuit that supplies a discharge current to the main discharge electrodes; and a starter that produces a high voltage between one of the main discharge electrodes and the auxiliary electrode, wherein, during a time interval during which the starter produces said high voltage, a high voltage is also applied to the main discharge electrodes at least during a portion of the time interval.

Abstract: A discharge lamp which eliminates the large line noise that forms in discharge lamps during startup while preventing heat loss in the transformer by providing a pair of opposed electrodes for the main discharge and an auxiliary electrode arranged such that it does not come into contact with the discharge space for the main discharge, a feed circuit for supplying the discharge current to the electrodes for the main discharge, and a starter circuit which produces a high voltage between one of the electrodes for the main discharge and the auxiliary electrode. The high voltage generating part of the starter circuit which includes at least a high voltage transformer that is separated from the feed circuit while the discharge lamp and the high voltage generating part are formed as an integral unit.

Abstract: Light source device which includes a discharge lamp which contains at least 0.15 mg mercury per cubic millimeter of the volume of the discharge space, a pair of electrodes opposite one another to create the main discharge and spaced a distance from one another of less than or equal to 2.5 mm, and an auxiliary electrode arranged such that it does not come into contact with the discharge space for the main discharge. The light source device further including a feed circuit to feed the discharge current to the electrodes for the main discharge, and a starter which produces a high voltage between one of the electrodes of the two electrodes for the main discharge and the auxiliary discharge, such that the starter produces a voltage two to five times as high as the voltage necessary for starting the main discharge in the lamp at the room temperature state.

Abstract: To provide a high-pressure mercury lamp capable of shortening the light output rise time and of preventing glow discharge that occurs when the lamp is lighted, a high-pressure mercury lamp (1) luminescent device with a pair of electrodes (6, 7) placed opposite one another within a discharge vessel (2) made of quartz glass with seals (4, 5) formed on both ends and at least 0.15 mg/mm3 of mercury sealed into the discharge vessel, has a device (11, 12) for increasing the temperature of the outer wall of the luminescent portion (3) of the discharge vessel (2) to at least 100° C. before the high-pressure mercury lamp is lit.