| 摘要 |
PROBLEM TO BE SOLVED: To restrict the VLF leakage electric field by applying the voltage to a conductor, which is synchronous with the waveform of the deflecting voltage and which has a polarity opposite to the polarity of the deflecting voltage. SOLUTION: Fly-back pulse at a high voltage is applied to a horizontal deflecting coil 8 for scanning, so as to display an image in a cathode-ray tube. At this stage, the VLF leakage electric field is emitted to a front surface panel part 2 of the cathode-ray tube by the induction work of the coil. At the same time, the voltage which is synchronous with the waveform of the deflection voltage of the horizontal deflecting coil 8 and which has a polarity opposite to the polarity of the deflecting voltage, is applied to a conductive film 4 from an opposite polarity voltage generating unit 9. Electric field having a polarity opposite to the polarity of the VLF leakage electric field, which is emitted from the horizontal deflecting coil 8, is generated so as to offset the VLF leakage electric field. Consequently, the VLF leakage electric field from the front surface panel part 2 can be substantially suppressed. Since an insulating film 3 is provided between the conductive film 4 and the deflecting device 5, even in the case where the voltage with opposite polarity is applied, arc discharge is not generated. |
