Abstract: A xenon lamp drive unit of the present invention comprises: a charging circuit; and a current control circuit adapted to supply a current to a xenon lamp by using a charged voltage of the charging circuit as a power source, wherein the current control circuit is adapted to supply, in a first period after a lamp ignition, a high output lamp current having a higher current value than a steady output lamp current to the xenon lamp by constant current control and supply, in a second period after the first period, the steady output lamp current to the xenon lamp by constant current control.

Abstract: The high pressure discharge lamp ballast drives a high pressure discharge lamp with a synthesized-waveform alternating current made of multiple frequency components, the high pressure discharge lamp having a pair of electrodes disposed to face each other. The ballast controls a ratio of the multiple frequency components per unit time; applies a synthesized-waveform current in accordance with the ratio to the high pressure discharge lamp; and detects a lamp parameter of the high pressure discharge lamp. The control circuit is configured to shift the ratio to a first ratio when the lamp parameter is in a first state, and shifts the ratio to a second ratio when the lamp parameter is in a second state. The control circuit changes the ratio stepwise when the ratio is shifted from the first ratio to the second ratio, or when the ratio is shifted from the second ratio to the first ratio.

Abstract: A high pressure discharge lamp ballast performs driving with a synthesized current waveform comprising a combination of first and second sets of current waveforms. The ballast controls content rates of each of the sets per unit time; detects a rotation synchronization signal for a color wheel; applies a synthesized current waveform in accordance with the synchronization signal and the content rates to a high pressure discharge lamp; and detects a lamp voltage. A period of each of the first and second sets equals to one rotation of the color wheel. The number of inversions of the second set is larger than that of the first set. The content rate of the second set is set to RL% when the lamp voltage exceeds a value V, and the content rate of the second set is set to RH% when lamp voltage falls below a value V?.

Abstract: The high pressure discharge lamp ballast of the present invention includes: power supply means for supplying an AC current to a lamp; and control means for cyclically changing a current value of the AC current to be supplied and a time interval between polarity inversions.

Abstract: A xenon lamp drive unit of the present invention comprises: a charging circuit; and a current control circuit adapted to supply a current to a xenon lamp by using a charged voltage of the charging circuit as a power source, wherein the current control circuit is adapted to supply, in a first period after a lamp ignition, a high output lamp current having a higher current value than a steady output lamp current to the xenon lamp by constant current control and supply, in a second period after the first period, the steady output lamp current to the xenon lamp by constant current control.

Abstract: The invention relates to a light source device having a high-voltage discharge lamp (1) on which a trigger line (10) for triggering the lamp is attached. The high-voltage discharge lamp (1) is formed such that an arc tube (7) having a pair of substantially cylindrical sealing portions (9R, 9L) formed on both sides in the longitudinal direction with a light emitting portion (8) in between is sealed with electrode assemblies (3R, 3L). The trigger line (10) is formed such that its one end (10a) is connected to a power supply lead (6), which is of the electrode assembly (3L) and protruded from the one sealing portion (9L), and its other end (10c) is wound around the outer circumference of the other sealing portion (9R).

Abstract: The invention relates to a light source device having a high-voltage discharge lamp (1) on which a trigger line (10) for triggering the lamp is attached. The high-voltage discharge lamp (1) is formed such that an arc tube (7) having a pair of substantially cylindrical sealing portions (9R, 9L) formed on both sides in the longitudinal direction with a light emitting portion (8) in between is sealed with electrode assemblies (3R, 3L). The trigger line (10) is formed such that its one end (10a) is connected to a power supply lead (6), which is of the electrode assembly (3L) and protruded from the one sealing portion (9L), and its other end (10c) is wound around the outer circumference of the other sealing portion (9R).

Abstract: In a frequency control for a high pressure discharge lamp ballast, short-term increase and decrease of a lamp voltage are suppressed. The high pressure discharge lamp ballast drives a high pressure discharge lamp with a synthesized-waveform alternating current made of multiple frequency components, the high pressure discharge lamp having a pair of electrodes disposed to face each other. The ballast includes: a control means for controlling a component contained ratio of the multiple frequency components per unit time; an output means for applying a synthesized-waveform current in accordance with the component contained ratio to the high pressure discharge lamp; and detection means for detecting a lamp parameter of the high pressure discharge lamp.

Abstract: Even when usable driving frequencies are limited, a lamp voltage is appropriately controlled. A high pressure discharge lamp ballast performs driving with a synthesized current waveform comprising a combination of first and second sets of current waveforms. The ballast includes: a control means for controlling content rates of each of the sets per unit time; a detection means for detecting a rotation synchronization signal for a color wheel; an output means for applying a synthesized current waveform in accordance with the synchronization signal and the content rates to a high pressure discharge lamp; and a detection means for detecting a lamp voltage. The sets are each in a waveform inverted so as to correspond to at least one of a rotational speed and segment positions of color wheel. A period of each of the first and second sets has a length equivalent to one rotation of the color wheel. The number of inversions of the second set is larger than the number of inversions of the first set.