Loading patent…
AssigneeKoito Manufacturing Co., Ltd.
InventorsMasayasu Yamashita, Atsushi Toda
Estimating the term…
In a lighting circuit, a battery voltage is supplied via a DC booster circuit to a DC-AC converter where the voltage is converted to an AC voltage with a rectangular waveform. This AC voltage is supplied to a discharge lamp. At this time, the DC-AC converter controls the frequency of the rectangular wave output from the DC-AC converter in accordance with a signal sent to a bridge type driver from a frequency controller. A lighting detector is provided to detect if the discharge lamp has been lighted. Upon reception of a signal from the lighting detector, the frequency controller sets the frequency of the output voltage of the DC-AC converter in the pre-lighting period of the discharge lamp higher than the frequency of the output voltage of the DC-AC converter after the lighting of the discharge lamp and restricts the inversion of the polarity of the output voltage of the DC-AC converter until a predetermined time passes sfrom the point of the activation of the discharge lamp.
A lighting circuit for a discharge lamp having DC-AC converting means for converting a DC voltage to an AC voltage which is to be supplied to said discharge lamp via an inductive load, said lighting circuit comprising:
A lighting circuit for a discharge lamp having DC-AC converting means for converting a DC voltage to an AC voltage which is to be supplied to said discharge lamp via an inductive load, said lighting circuit comprising:
Dependencies are inferred from the claim text.