| 摘要 |
PROBLEM TO BE SOLVED: To realize lower cost and lower power consumption, and improve starting characteristics of a discharge lamp with a larger lamp length, by providing a current asymmetrizing means for only the discharge lamp with a larger lamp length inclined to generate striation among a plurality of discharge lamps different in lamp length. SOLUTION: With fluorescent lamps FL1, FL2 with different lamp lengths connected to a lighting device, a series circuit of a diode D5 and a resistor R5, as lamp-current asymmetrizing means, is connected in parallel to the lamp FL2 with a larger lamp length inclined to generate striation. The lamp FL2 with a larger lamp length equipped with the lamp-current asymmetrizing means 12 is improved in start characteristics because a direct-current voltage direct- current-biased by the means 12 is superimposed on a secondary voltage of the lighting device 13 at starting, and striation is not generated and flickering does not happen because lamp current is made asymmetric by the means 12 at the time of lighting. Power loss and cost due to the means 12 can be reduced because the means 12 is provided only for the lamp FL2 with a larger lamp length. |
