| 摘要 |
PURPOSE:To eliminate color ringing on a screen by constituting the circuit for a filter for a photo diode after a preamplifier so as not to be atteneded with the free oscillation of a CR circuit or an LR circuit. CONSTITUTION:The CR circuit applied to the filter 5 consists of a capacitor 91, a resistor 92, an input terminal 93 and an output terminal 94. The CR circuit consists equivalently of a capacitor 101, a resistor 102, a switch 103, a DC power supply 104, and an output terminal 105. In closing the switch 103 of the CR circuit, the voltage at the output terminal 105 is fluctuated in terms of transient state. In this case, since the CR circuit does not behave oscillatory as an LCR circuit, a normal index signal is not suppressed by the free oscillation of the filter but the normal index signal is obtained. |
