TH42115A - Dynamic focusing voltage amplitude controller and high-frequency compensation. - Google Patents

Abstract

The DC60 (21/12/42) video imaging device contains a cathode ray tube (10) with a focusing electrode (17) and a source of the first parabola signal (V5) at a frequency related to the refraction frequency, which is selected from a number of frequencies, with an amplitude determined by the selected frequency. A control circuit (Figure 1B) has an input signal connected to the first parabola signal source (V5) to generate an output signal (OUT). The output signal is used to maintain the amplitude of the first parabola signal (V5) for a number of refraction frequencies. An amplification circuit (97), which responds to the output signal, is connected to the focusing electrode (17) to amplify the parabola signal to generate focusing voltage. Dynamics at the focusing electrode. The video imaging device contains a cathode ray tube (10) with a focusing electrode. The focusing electrode (17) is a source of the first parabola signal (V5) at a frequency relative to the refraction frequency, which is selected from a number of frequencies, with an amplitude determined by the selected frequency. The control circuit (Figure 1B) has an input signal connected to the first parabola signal source (V5) to generate an output signal (OUT). The output signal is used to maintain the amplitude level of the first parabola signal (V5) for a number of refraction frequencies. An amplification circuit (97), which responds to the output signal, is connected to the focusing electrode (17) to amplify the parabola signal to generate a focusing voltage. The dynamics at the focusing electrode

Claims (5)

1. The video imaging device consists of the following components: a cathode ray tube (10) with a focusing electrode (17); a source (CS1) of the first parabola signal (V5) at a frequency corresponding to the refraction frequency, selected from a number of frequencies, with an amplitude determined by the selected frequency, characterized by a control circuit (Figure 1B) with an input signal (C4) connected to the source of the first parabola signal to generate an output signal (OUT) to maintain the amplitude of the first parabola signal at a number of refraction frequencies; and an amplification circuit (97) that responds to the output signal and is connected to the focusing electrode (17) to amplify the parabola signal to generate a dynamic focusing voltage at the focusing electrode. 2. A video imaging device as per claim 1, which is characterized by the control circuit (Figure 1B) containing a voltage amplitude return loop. 3. The video imaging device under claim 2, which has the special characteristic of a reverse loop, the voltage amplitude of which shall also include a low-pass filter circuit (R55, C54). 4. A video imaging device under claim 3, which is characterized by a low-pass filter circuit that compensates for high frequencies. 5. A video imaging device according to claim 1, which is characterized by the first parabolic signal (V5) being added to an S-shaped capacitor (CS1) and connected in a capacitive manner (C4) to the control circuit.