发明名称 |
Color television receiver |
摘要 |
A color television receiver includes a color picture tube having three electron guns including cathodes and heaters therefor, respectively, and an automatic cutoff adjusting circuit for adding a reference voltage signal substantially at a black level to a luminance signal during an interval beginning substantially at the end of a vertical blanking period, and for detecting cathode currents flowing toward the cathodes during the above-described interval to control cathode voltages for the cathodes for keeping the cathode currents at a predetermined level by way of feedback of voltages proportional to the cathode currents. There is provided a circuit for applying a positive voltage to each of the heaters during the above-described interval to reduce a potential difference between the heater and corresponding one of the cathodes to thereby lower a leakage current flowing between the cathode and the heater.
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申请公布号 |
US4514664(A) |
申请公布日期 |
1985.04.30 |
申请号 |
US19820376662 |
申请日期 |
1982.05.10 |
申请人 |
HITACHI, LTD. |
发明人 |
KASAGI, KUNISUKE;KAWASHIMA, MACHIO |
分类号 |
H04N9/18;H04N9/20;H04N9/72;H04N9/73;(IPC1-7):H01J29/52;H04N9/535 |
主分类号 |
H04N9/18 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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