| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric discharge lamp lighting or illumination device capable of maintain its high input power-factor during full lighting, enabling deep light adjustment without causing low-frequency ripples (flickering) even during light adjustment, and satisfying high-frequency restrictions on the input current of the power supply. SOLUTION: In an electric discharge lamp lighting device of complex circuit system, when the pulse width or frequency of a switching pulse for driving a switching transistor Q11 of an inverter is controlled, the pulse width or frequency is so controlled as to be control light adjustment according to the degree of light adjustment during light adjustment, and the on duration or switching frequency of said switching transistor Q11 is so controlled as to control low distortion so that the instantaneous value of an alternating current power supply AC differs with its high or low duration. On the other hand, the low-frequency ripples to be generated during light output of a discharge lamp 24 is controlled to be reduced during light adjustment, and said low distortion control is controlled to be partially or entirely released in the half cycle of the alternating current power supply AC. |
