| 摘要 |
PROBLEM TO BE SOLVED: To quickly, simply start a high pressure discharge lamp by forming high transfer voltage by voltage doubling with a charging capacitor divided into two partial capacitors of a rectifier unit, and connecting the middle point of the charging capacitor to one power input side of the rectifier unit. SOLUTION: Power source filtering of a power source voltage applied across terminals CE1, CE2 is conducted with a circuit NF, rectifying of a power source is conducted with a bridge rectifying circuit GB, and a peak value of power input voltage doubled with a voltage doubling circuit is supplied. This operation is conducted in a no-load state when a lamp is not yet ignited. In the voltage doubling circuit, a charging capacitor LK in the rear part is divided into two separate capacitors C1, C2, and the common middle point of them is connected to one of two power input sides in a bridge rectifying circuit. The other contact point of each of both capacitors is earthed or kept in a pulse potential of power source voltage. |
