| 摘要 |
PROBLEM TO BE SOLVED: To provide lighting equipment, which secures the reliability of the electric discharge lamp lighting equipment at the time of abnormalities, such as the life last stage of the electric discharge lamp, or the like, and certainly has the starting lighting function of the electric discharge lamp also in the case of environmental change, by suppressing the cost rise with as possible as simple composition. SOLUTION: It has a power supply smoothing circuit 1, which converts a commercial power supply AC into direct-current voltage, an inverter circuit 2, which makes an electric discharge lamp La turn on by converting the above direct current voltage into high frequency by one or more switching elements Q1 and Q2, a lamp-life last stage detection circuit 3, which has the function that makes the rise of oscillation frequency or the oscillation stop in the life last stage of the electric discharge lamp La, and a starting voltage peak detection circuit 5, which has the function that maintains the starting voltage approximately if it reaches the starting voltage required for the lamp starting. The value of the same course to the monitor value, which the lamp life last stage detection circuit 3 is supervising, is made to be supervised also in the starting voltage peak detection circuit 5. |
