JPS58147358U

JPS58147358U - Bright spot elimination circuit

Info

Publication number: JPS58147358U
Application number: JP4427182U
Authority: JP
Inventors: 公博横手
Original assignee: 日本電気ホームエレクトロニクス株式会社
Priority date: 1982-03-29
Filing date: 1982-03-29
Publication date: 1983-10-04

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of the drawing]

第１図は従来のテレビジョン受像機の要部の回路図、第
２図は同上の回路動作を説明するための電圧特性図、第
３図は本考案の一実施例を示すテレビジョン受像機の要
部の回路図、第４図は同上の回路動作を説明するための
電圧特性図である。１・・・・・・映像増幅回路、２・・・・・・ブランキ
ング回路、４・・・・・・輝度調整機能を有する輝点消
去回路、ＣＲＴ・・・・・・受像管、Ｋ・・・・・・カ
ソード、Ｇ１・・・・・・コントロールグリッド、Ｄ３
・・・・・・ダイオード、Ｇ３・・・・ｉ・コンデンサ
、Ｒｌｏ、Ｒ□１・・・・・・抵抗、ＶＲ□・・・・・
・可変抵抗器、ＶＫ・・・・・・カソード電圧、Ｖ６・
・・・・・コントロールグリッド電圧。Figure 1 is a circuit diagram of the main parts of a conventional television receiver, Figure 2 is a voltage characteristic diagram for explaining the operation of the same circuit, and Figure 3 is a television receiver showing an embodiment of the present invention. FIG. 4 is a voltage characteristic diagram for explaining the operation of the circuit. 1... Video amplification circuit, 2... Blanking circuit, 4... Bright spot erasing circuit with brightness adjustment function, CRT... Picture tube, K ...Cathode, G1 ...Control grid, D3
...Diode, G3...i capacitor, Rlo, R□1...Resistance, VR□...
・Variable resistor, VK...Cathode voltage, V6・
...Control grid voltage.

Claims

[Scope of utility model registration request]

In a display device using a picture tube, a charging current is applied to one terminal in response to power on to the device so that one terminal of the capacitor is always maintained as a positive terminal and the other terminal as a negative terminal. The unidirectional semiconductor element to be supplied is electrically conductive in the power-on state and non-conductive in the power-off state, and one end of the unidirectional semiconductor element is connected to the capacitor in order to form a part of the discharge path of the capacitor. a resistor coupled to one terminal side and whose other end is coupled to the other terminal side of the capacitor; the other terminal side of the capacitor is coupled to the control grid of the picture tube; and when the power supply is cut off; A bright spot erasing circuit characterized in that the resistance value of the resistor is set so that the voltage of the control grid is maintained at a negative potential with respect to the cathode voltage of the picture tube.