| 摘要 |
PURPOSE: An apparatus for controlling speed modulation of electron beam in television is provided to remove a current component for modulating an electron beam speed within an OSD section or a caption data section. CONSTITUTION: An apparatus for controlling speed modulation of electron beam in television comprises a first amplification portion(102), a high pass filter(104), a buffer(106), a second amplification portion(108), a speed modulation portion(110), a deflection yoke(112), an OSD signal detection portion(118), a caption signal detection portion(120), a switching control portion(116), and a switching portion(114). The first amplification portion amplifies an input luminance signal. The high pass filter filters a luminance component except for a peaking component. The buffer buffers a luminance component without the peaking component. The second amplification portion amplifies the luminance component to a current level for an electron beam speed modulation level. The speed modulation portion modulates an electron beam speed according to the current level. The deflection yoke deflects the electron beam. The OSD signal detection portion detects an OSD signal. The caption signal detection portion detects a caption signal. The switching control portion provides a switching control signal according to the caption signal and the OSD signal. The switching portion grounds the peaking component according to the switching control signal.
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