Patent ID: 6144416
Filing Date: 2000-11-07
Classification: H01J,H04N

Abstract:
An apparatus of shielding a very low frequency electric field emitted from a front face of a cathode ray tube (CRT) in a video appliance for generating a high voltage through a flyback transformer which is supplied to an anode of the CRT, and inducing a negative polarity pulse signal through an induction coil wound around a core of the flyback transformer, the apparatus comprising:a signal detection section, connected to the flyback transformer, for detecting the voltage applied to the anode of the CRT, the signal detection section comprising a capacitor, connected to one terminal of a smoothing capacitor connected to the flyback transformer, for detecting the voltage applied to the anode of the CRT;an inversion-amplifying section for inversion-amplifying the voltage detected by the signal detection section;a waveform-shaping section for waveform-shaping the pulse signal induced from the induction coil;a signal synthesizing section for synthesizing the negative polarity pulse signal inputted from the waveform-shaping section with an output signal of the inversion-amplifying section;an output amplifying section for amplifying the synthesized pulse signal inputted from the signal synthesizing section; andan antenna, mounted on a predetermined portion of the CRT, for radiating the synthesized pulse signal inputted from the output amplifying section.