| 摘要 |
PURPOSE: To prevent the unevenness of light emission without enlarging a lighting device or a lighting circuit by winding an auxiliary coil, which is connected in series to a constant current inductance, around the center tap of a primary winding of a high frequency invertor. CONSTITUTION: In a high frequency invertor 7 having power sources 6a, 6b, a constant current inductance 7a and a transformer 7b, an auxiliary winding 7b3, which is connected in series to the inductance 7a, is wound around a center tap of primary windings 7b, 7b'1 for arrangement. Electric field of this auxiliary winding 7b3 gives the influence to the voltage waveform of a sign wave respective generated in the winding 7b1, 7b'1 and a base coil 7b"1. Namely, the voltage waveform output from the invertor 7 is changed to the appropriate asymmetric waveform, and output, and the striation of a low pressure ion discharge lamp can be avoided, and the discharge lamp functions as a light source of high quality. Asymmetric ratio of the voltage waveform to be output from the invertor 7 is set in a range at approx. 10-60%. |
