| 摘要 |
PURPOSE: To lower the sensitivity of a ballast with respect to the fluctuation of constituent elements and a lamp by an impedance matching circuit of the ballast for a self-oscillation type electrodeless lamp, in which an inductor is connected in series with a parallel combination of a capacitor and a lamp-drive coil. CONSTITUTION: This ballast is provided with an additional capacitor Cs in series with a lamp-drive coil 14. Due to the additional capacitor, the phase angle from the view of the ballast is made small and consequently, the sensitivity of the ballast with respect to the fluctuation of the constituent elements and the lamp is lowered. Further, since the impedance in the overall circuit network is lowered, the necessary inductance of the inductor L2 connected in series is lowered, and the number of the turns of the inductor is lessened and the conduction loss is decreased. |
