| 摘要 |
PROBLEM TO BE SOLVED: To reduce size and reduce cost by simplifying a circuit for generating supply voltage necessary for generating starting pulses being supplied to a discharge lamp, and generate the start pulses at constant intervals. SOLUTION: A capacitor C1 and a switching element SG are installed on the primary side of a transformer TT inside a starting circuit 5, and when the switching element SG is closed, accumulated charges of the C1 is discharged, and starting pulses are supplied to the discharge lamp. A capacitor C2 and a rectifying element D2 are installed between the output of a DC-AC conversion circuit 4 and a ground, and the C2 is charged by current flowing toward the element D2. A capacitor C3 and a rectifying element D3 are installed between the connection point of a secondary winding T2 of a transformer T, constituting the DC-AC converting circuit and a rectifying element D1, and a connecting point on a line connecting the C2 and the element D2, the C3 is charged by current flowing toward the element D3. The connecting point of the C3 and the element D3 is connected to a voltage supply line to the C1 of the starting circuit 5, so that the charges are accumulated. |
