| 摘要 |
PURPOSE:To make an auxiliary anode driving current larger at the peripheral part than at the center part and to hold the discharge of the whole panel to a constant characteristic by inputting a parabolic control waveform to the bases of transistors of an auxiliary anode driving circuit. CONSTITUTION:A constant current control circuit 15 is connected to the bases B of the transistors(TR) 12 in the auxiliary anode driving circuit 6 and outputs the parabolic signal to drive the TRs 12. Consequently, an auxiliary discharging current outputted from the collector C of each TR 12 varies in a parabolic shape after the start of discharging similarly to the output signal of the circuit 15. Then the constant current control circuit 15 outputs one parabolic waveform in each vertical scanning period of a discharge panel 1 to supply a large auxiliary anode current to the upper and lower peripheral parts which are harder to illuminate than the center part, thereby holding the discharge of the entirety in the vertical direction to the constant characteristic. |
