| 摘要 |
PURPOSE:To reduce the power of a DC voltage application circuit without deteriorating the picture quality by inserting a resistor between a focus electrode and the DC voltage application circuit and connecting a capacitor between the focus electrode and ground. CONSTITUTION:A resistor 65 is inserted between a focus electrode (connection terminal 64) and a DC voltage application circuit 67 and a capacitor 66 is connected between the focus electrode and ground. A control signal 68 is applied from a drive circuit 81 to a connection terminal 62 of a beam flow control electrode, the signal passes through a capacitor 63 and appears at the connection terminal 64, the amplitude of the signal is divided by the capacitance ratio of the capacitors 63, 66 and the result becomes a signal 69. When the capacitance of the capacitor 66 is taken sufficiently larger than that of the capacitor 63, the amplitude of the signal 69 is decreased without giving effect on the focus of an electron beam and a pedestal level 70 of the signal 69 is given by the DC voltage application circuit 67 and the resistor 65 to reduce the current flowing from the DC voltage application circuit 67. Thus, the power consumption of the DC voltage application circuit is reduced without deterioration in the picture quality. |
