LIGHTING CIRCUIT DEVICE FOR LOW-PRESSURE DISCHARGE LAMP AND ILLUMINATION DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a lighting circuit device for lowering a change of filament voltage on lamp lighting and enabling stable lighting by using a common high frequency lighting circuit (an inverter) for low-pressure discharge lamps with different lengths of glass tube valve or lamp power and an illumination device using this lighting circuit device. SOLUTION: With the lighting circuit device 1 with a low-pressure discharge lamp L having an inverter circuit 4 and a pair of filament electrodes L2, L2 connected to a direct current power supply 2, the above oscillating circuit has an inductance 6 and a capacitor 7 connected in series and a lamp L and the capacitor 7 connected in parallel and further, the device 1 and the illumination device using this lighting device 1 is so made to have a filament voltage applied of a sum of a feed-back voltage from a feed-back circuit detecting lamp voltage at filament electrodes L2, L2 and a voltage from the capacitor 7.