KR0121383Y1 - Horizontal dynamics focusing circuit - Google Patents

Abstract

The present invention relates to the improvement of the focus performance of a TV or monitor CRT in a horizontal dynamic focus circuit. As the CRT becomes larger and wider (16: 9 aspect ratio), the panel surface of the CRT becomes aspheric, so that the electron beam of the screen The difference between the distances reaching the center and periphery points does not have a parabolic trajectory. Therefore, when the dynamic focus voltage is applied in the parabolic shape, the difference of the arrival trajectory and the distance of the electron beam due to the aspherical surface of the CRT panel is generated. There was a problem in that the uniformity of the focus is limited and the quality is restricted.

Therefore, in order to solve the above problems, the present invention generates a resonant frequency voltage of the multiples for correcting the horizontal parabola voltage to a shape suitable for the aspherical CRT form in the correction circuit unit 16, which causes the focus transformer unit 17 to It is a horizontal dynamic focusing circuit which tries to equalize focus and improve clarity by applying a dynamic focus voltage of a corrected form to the CRT focus electrode by superimposing a DC focus voltage on the CRT panel trace.

Description

Horizontal dynamic focus circuit

Figure 1 (a) is a detailed view showing the electron beam reaching distance by the panel surface of the conventional single-spherical CRT tube (b) is a detailed view showing the electron beam reaching distance by the panel surface of the conventional aspheric CRT

2 is a circuit diagram showing the configuration of a conventional horizontal dynamic focus circuit.

3 is a circuit diagram showing the configuration of the horizontal dynamic focus circuit of the present invention

(A) and (b) of FIG. 4 are waveform diagrams represented by the horizontal dynamic focus voltage of the present invention, and (c) is a detailed view showing the electron beam reaching distance by the panel surface of the CRT.

5 is a circuit diagram showing another embodiment of the present invention a horizontal dynamic focus circuit configuration

* Explanation of symbols for main parts of the drawings

11: horizontal oscillation part 12: horizontal drive circuit part

13 horizontal output circuit 14 flyback transformer unit

15: waveform shaping circuit portion 18: power supply portion

16: horizontal dynamic focus voltage correction circuit portion 19: high voltage drive circuit portion

17: dynamic focus transformer section 20: high voltage output circuit section

The present invention relates to the improvement of the focus performance of a TV or monitor CRT in a horizontal dynamic focus circuit. Especially, when the CRT adopts an aspheric CRT as the CRT becomes larger and more flat, it is suitable for the aspherical CRT type to the horizontal parabola voltage to improve its image quality. This is to apply the dynamic focus voltage of the corrected type to the CRT focus electrode by superimposing the resonant frequency voltages of multiples to be corrected.

In general, a CRT of a TV or a monitor focuses an electron beam on an electrostatic lens formed between an anode and an anode by applying an appropriate voltage to a focus electrode so that a clear image appears on a screen by an electron beam emitted from an electron gun. Since the distance between the beam and the arrival point of the electron beam varies from the center of the spherical CRT to the top, bottom, left and right as shown in (a) of FIG. 1, the focus voltage should be changed according to the arrival point of each beam. The peripheral voltage is changed and applied to the parabola waveform.

The configuration and operation of a conventional horizontal dynamic focus circuit with reference to the CRT of a general TV or monitor as described above will be described with reference to FIG. 2.

First, the conventional circuit configuration includes a horizontal oscillator 1 for receiving a synchronization signal of a horizontal period and outputting a horizontal drive pulse, a horizontal drive circuit 2 for current amplifying the horizontal drive pulse, and the current amplified horizontal drive. A horizontal output circuit section 3 for flowing a deflection current in a horizontal scanning period using a switching element and generating a flyback pulse in a horizontal retrace section, and boosting and rectifying the generated flyback pulse to a high voltage and The flyback transformer unit 4 which applies the focus voltage and the screen voltage to the corresponding electrode of the CRT, and receives the inverse flyback pulse generated from the tertiary winding of the flyback transformer unit 4 and integrates it to the horizontal parabola. A waveform shaping circuit section 5 to be shaped into a shape, and boosting the shaped voltage to form the flyback transformer through a capacitor C3. The dynamic focus transformer unit 6 superimposes the DC focus voltage generated by the unit 4 and applies a horizontal parabola-type horizontal dynamic focus voltage to the dynamic focus electrode of the CRT.

The horizontal output circuit unit 3 deflects the horizontal output transistor Q1 turned on / off according to the current amplified horizontal drive pulse and the electron beam scanned on the CPT according to the deflection current inputted by the on / off. And the S-shaped correction capacitor Cs1 for correcting the S-shape of the deflection current flowing through the deflection coil LDY1, and the flyback transformer unit 4 includes the primary coil L2. The secondary side coil (L4) is induced by a constant double voltage of the primary coil (L2) and the constant side voltage is applied to the tertiary side applied to the waveform shaping circuit (5) while generating a reverse flyback pulse. It consists of a coil (L3), the waveform shaping circuit unit 5 is composed of a coil (L1) and a capacitor (C2) for receiving and integrating the generated reverse flyback pulse.

Reference numeral C1 denotes a resonant capacitor, D1 denotes a damper diode, D2-D4 denotes a diode, R1, R2 denotes a resistor, and L5 and L6 denote coils.

Referring to the operation of the conventional horizontal dynamic focus circuit configured as described above is as follows.

When a registration signal of a horizontal period is input to the horizontal oscillation unit 1 and a horizontal drive pulse is applied to the horizontal drive circuit unit 2, the horizontal drive circuit unit 2 amplifies the horizontal drive pulses so that the horizontal output circuit unit 3 is When the horizontal output transistor Q1 is applied to the base of the horizontal output transistor Q1 and the horizontal output transistor Q1 is turned on, the second half section of the scan has the voltage B + charged in the S-shaped correction capacitor Cs1 along the horizontal deflection coil LDY1. A deflection current flows through the path of the horizontal output transistor Q1, and in the scan half-section, the back electromotive force of the horizontal deflection coil LDY1 becomes larger than the voltage B + charged in the S-shaped correction capacitor Cs1 during the return period, and a damper diode. In (D1), a horizontal deflection current flows through the path of the horizontal deflection coil LDY1. In addition, when the horizontal output transistor Q1 is turned off, in the horizontal retrace period, a parallel resonance of the horizontal deflection coil LDY1 and the resonant capacitor C1 causes a flyback pulse to be generated at the collector of the horizontal output transistor Q1, thereby causing a flyback transformer. It is applied to the difference side coil L2 of the part 4. In addition, the flyback transformer unit 4 boosts the flyback pulse applied to the primary coil L2, and a constant voltage is induced in the secondary coil L4 to rectify the respective diodes D2, D3, and D4. do.

At this time, the high voltage rectified by the diode D2 is output to the anode of the CRT, and the constant voltage rectified by the diode D3 is divided by the resistors R1 and R2 connected in parallel, and then the static focus electrode and the dynamic focus of the CRT. The voltage is output to the electrode, and the voltage rectified by the diode D4 is output to the ABL.

In addition, the reverse flyback pulse generated from the tertiary winding L3 of the flyback transformer unit 4 is applied to the waveform shaping circuit unit 5 to integrate the integrated circuit composed of the coil L1 and the capacitor C2. Is applied to the primary coil L5 of the horizontal dynamic focus transformer unit 6 while being shaped to a horizontal parabola voltage, the secondary coil L6 of the horizontal dynamic focus transformer unit 6 is focused on the peripheral focus of the CRT. Stepped up to the required size of the parabola shape, and passed through the capacitor (C3) and superimposed on the DC dynamic focus voltage generated in the flyback transformer unit 4 is applied to the dynamic focus electrode of the CRT.

However, as shown in Fig. 1, as the CRT becomes larger and wider (16: 9 aspect ratio), the panel surface of the CRT becomes aspheric as in (b), so that the electron beam reaches each center and periphery of the screen. The difference in the distance does not have a parabolic trajectory. Therefore, when the dynamic focus voltage is applied in the parabola form as in the case of (a), the difference of the arrival trajectory and the distance of the electron beam due to the aspherical surface of the CRT panel is generated. There was a problem in that the uniformity of the focus is limited and the quality is restricted.

Therefore, in order to solve the conventional problem, the present invention superimposes the horizontal parabola voltage on the CRT tube to superimpose the resonant frequency voltage of the multiple to correct the aspheric CRT shape. In order to make the focus uniform and improve the sharpness.

The configuration and operation of the present invention horizontal dynamic focus circuit for achieving the above object will be described with reference to FIGS. 3 and 4.

Referring to FIG. 3, the horizontal dynamic focus circuit of the present invention includes a horizontal oscillator 11 for receiving a synchronization signal of a horizontal period and outputting a horizontal drive pulse, a horizontal drive circuit 12 for current amplifying the horizontal drive pulse; And a horizontal output circuit 13 for generating a flyback pulse in a horizontal retrace section while the deflection current flows in the horizontal scanning period by using the switching device to amplify the current-amplified horizontal drive pulse. In the third winding of the flyback transformer unit 14 and the flyback transformer unit 14 for generating a DC focus voltage by applying a high voltage and a focus voltage and a screen voltage necessary for the CRT operation to the corresponding electrodes of the CRT. A waveform shaping circuit unit 15 for receiving the generated inverse flyback pulse and integrating the same to form a horizontal parabola; A horizontal dynamic focus voltage correction circuit 16 for generating a resonance voltage of a multiple frequency of the horizontal horizontal parabola overlapping the resonance voltage and the horizontal parabola voltage, and boosting the overlapping resonance voltage and the horizontal parabola voltage, and then the capacitor C13. The dynamic focus voltage is applied to the dynamic focus electrode of the CRT by applying a horizontal parabola-type horizontal dynamic focus voltage of the corrected type to the aspherical surface area of the CRT panel. It consists of the focus former 17.

The horizontal output circuit 13 deflects the horizontal output transistor Q11 that is turned on / off according to the current-amplified horizontal drive pulse and the electron beam that is scanned on the CPT according to the deflection current input by the on / off. And a S-shaped correction capacitor Cs11 for correcting an S-shaped deflection current flowing through the deflection coil LDY11. The flyback transformer part 14 includes a primary coil L12. The secondary coil L14, where a constant back pressure is induced, and the secondary coil L14, which is induced by a constant back pressure of the primary coil L12 and generates a reverse flyback pulse, is applied to the waveform shaping circuit 15. L13), and the waveform shaping circuit unit 15 is composed of a coil (L11) and a capacitor (C12) for receiving and integrating the generated reverse flyback pulse.

In addition, the horizontal dynamic focus voltage correction circuit unit 16 includes a coil L17 and a capacitor C15, which are parallel resonant circuits for generating a resonance voltage of a frequency multiple of the horizontal parabola voltage, and converts the parallel resonant voltage into a waveform shaping circuit unit. The capacitor C12 of (15) and the capacitor C14 which divide and overlap with the capacitor C14 of the said horizontal dynamic focus voltage correction circuit part 16 are comprised.

Reference numeral D11 denotes a damper diode, C11 denotes a resonant capacitor, R11 and R12 denote a resistor, D12-D14 denotes a diode, and L15 and L16 denote coils.

Referring to the operation of the present invention the horizontal dynamic focus circuit configured as described above is as follows.

When the horizontal cycle synchronizing signal is input to the horizontal oscillation unit 11 and the horizontal drive pulse is applied to the horizontal drive circuit unit 12, the horizontal drive circuit unit 12 amplifies the horizontal drive pulses to generate the horizontal output circuit unit 13. It is applied to the base of the horizontal output transistor Q11.

Accordingly, when the horizontal output transistor Q11 is turned on, the second half of the scan section has a voltage B + charged in the S-shaped correction capacitor Cs11 along the horizontal deflection coil LDY11 of the horizontal output transistor Q11. As the deflection current flows through the path, the horizontal half-turn coil in the damper diode D11 becomes larger as the counter electromotive force of the horizontal deflection coil LDY11 becomes larger than the voltage B + charged in the S-shaped correction capacitor Cs11 during the return period. A horizontal deflection current flows through the path of LDY11.

In addition, when the horizontal output transistor Q11 is turned off, in the horizontal retrace period, a flyback pulse is generated by the parallel resonance of the horizontal deflection coil LDY11 and the resonant capacitor C11 to the collector of the horizontal output transistor Q11 to generate the flyback transformer. It is applied to the primary coil L12 of the former 14.

In addition, the flyback transformer unit 14 boosts the flyback pulse applied to the primary coil L12, and a constant voltage is induced in the secondary coil L14 to rectify the respective diodes D12, D13, and D14. do.

At this time, the high voltage rectified by the diode D2 is output to the anode of the CRT, and the constant voltage rectified by the diode D3 is divided by the resistors R11 and R12 connected in parallel, and then the static focus electrode and the dynamic focus of the CRT. Output to the electrode, the rectified voltage from the diode (D4) is fed to the ABL.

In addition, the reverse flyback pulse generated from the tertiary winding L13 of the flyback transformer unit 14 is applied to the waveform shaping circuit unit 15 to be integrated in an integrated circuit composed of a coil L11 and a capacitor C12. And a resonance voltage of about three times the frequency of the shaped horizontal parabola voltage by the parallel resonant circuit coil L17 and the capacitor C15 formed in the horizontal dynamic focus voltage correction circuit unit 16 while being shaped to the horizontal parabola voltage. As shown in (b) of FIG.

At this time, the generated parallel resonant voltage is divided into a capacitor C12 of the waveform shaping circuit unit 15 and a capacitor C14 of the horizontal dynamic focus voltage correction circuit unit 16 so as to overlap the capacitor C14.

As a result, the original horizontal parabola voltage becomes the same as the solid line A portion of FIG. 4A, and the CRT surface is aspherized so that the electron beam reach is changed so that the horizontal dynamic focus transformer part 17 The DC dynamic voltage generated by the flyback transformer unit 14 is applied to the primary coil L15 while outputting a boosted output to the secondary coil L16 and passing the output boosted voltage through the capacitor C13. It is applied to the dynamic focus electrode of the CRT by overlapping with the focus voltage.

The distance from the deflection center to the CRT surface is flattened as the CRT panel surface in the sections (C) and (F) of the solid line (A ') in Fig. 4 (c) from the panel surface of the aspherical CRT becomes flatter. On the other hand, the parabola voltage in the dotted line (B) section of FIG. 4 (a) is insufficient, and the focus in sections (C) and (F) of (c) of FIG. It spreads and gets worse.

In the section (c) of (c), the distance from the center of deflection to the surface of the CRT panel becomes shorter as the CRT surface becomes flat like the solid line A ', while the dotted line B of FIG. In the parabolic waveforms such as), the voltage in each section is large, so the focus in section (D) of (C) becomes spread and worsens.

Therefore, in order to flatten the CRT, the distance from the deflection center to the CRT surface in the section C, F of the solid line A 'becomes longer as the aspheric section C, D, E of (c). As a result, the horizontal dynamic parabola voltage is increased and applied, and in the section D of the solid line A ', the distance of the CRT panel is shortened, so that the horizontal dynamic parabola voltage is lowered to the aspherical surface according to the flattening of the CRT panel. By applying the corrected horizontal dynamic parabola voltage, the CRT panel is flat and clear at the same time.

FIG. 5 illustrates an embodiment of a horizontal dynamic focus circuit in which a flat portion and a high voltage portion are separated, and the configuration and operation thereof will be described below.

First, a horizontal oscillator 11 for receiving a synchronization signal of a horizontal period and outputting a horizontal drive pulse, a horizontal drive circuit 12 for amplifying the horizontal drive pulse, and a current amplified horizontal drive pulse for switching elements. A horizontal output circuit 13 for generating a horizontal parabola voltage while a horizontal current flows during the horizontal scanning period, a power supply 18 for receiving the generated voltage and applying a secondary voltage required for each circuit, and the horizontal output The horizontal dynamic focus voltage correction circuit 16 superimposing the parallel resonant voltage on the horizontal parabola voltage of the circuit 13 and the dynamic focus electrode of the CRT through the capacitor C13 after boosting the superposed resonance voltage and the horizontal parabola voltage. Horizontal dynamic focus in the form of a calibrated flat horizontal parabola for the aspherical surface area of the CRT panel Dynamic focus transformer unit 17 for applying pressure, a high voltage drive circuit unit 19 driven by receiving a horizontal drive pulse of the horizontal oscillating unit 11, and the flyback transformer unit receiving the horizontal drive pulse It consists of the high voltage | voltage output circuit part 20 which outputs to (14).

In addition, the horizontal output circuit unit 13 is configured to obtain a horizontal parabola voltage in the S-shaped correction capacitor Cs11, and the same reference numerals for the same parts as those in FIG. 3 are omitted.

The operation of the horizontal dynamic focus circuit in which the deflection portion and the high voltage portion configured as described above are separated is as follows.

It is applied to the power supply unit 18 of the horizontal parabola voltage generated by the S-shaped correction capacitor Cs11 of the horizontal output circuit unit 13 to apply the secondary voltage required for each circuit, and the horizontal parabola voltage is applied to the horizontal dynamic focus voltage correction circuit unit. The voltage corrected for the aspherical panel surface in the case of (b) of FIG. 1 in the dynamic focus former unit 17 by overlapping the parallel resonance voltage composed of the coil L17 and the capacitor C15 of (16) is 1. The voltage is applied to the primary coil L15, and the phase coil is reversed by the secondary coil L16 by the primary coil L15 to supply the boosted voltage to the dynamic focus voltage of the CRT through the capacitor C13.

At this time, when the horizontal drive pulse of the horizontal oscillation unit 11 is input from the high voltage drive circuit unit 19 and outputs the high voltage driving pulse, the flyback transformer unit 14 of the high voltage stage is input by the high voltage output circuit unit 20 receiving the pulse. Is applied to the dynamic focus electrode of the CRT by overlapping the DC focus voltage and the voltage boosted by the phase inversion at the secondary coil L16.

As described above, the present invention superimposes the horizontal parabola voltage on the CRT tube by applying a corrected dynamic focus voltage to the CRT panel trajectory by superimposing a resonant frequency voltage of multiples to compensate for the aspheric CRT shape. This has the effect of equalizing the focus and improving the sharpness.

Claims (3)

A horizontal output circuit unit 13 which receives a horizontal drive pulse and flows a deflection current for horizontal scanning and switches the primary winding of the flyback transformer unit 4 to generate a flyback pulse in the horizontal retrace section; A flyback transformer unit 14 for boosting and rectifying the flyback pulse generated by the horizontal output circuit unit 13 to apply the high voltage and the focus voltage and the screen voltage required for the CRT operation to the corresponding electrode of the CRT, and the flyback A waveform shaping circuit unit 15 for receiving the inverse flyback pulse generated in the third winding of the transformer unit 14 and integrating it to generate a horizontal parabola shape, and generating a resonance voltage of a multiple frequency of the shaped horizontal parabola. And a horizontal dynamic focus voltage correction circuit 16 which overlaps the resonance voltage and the horizontal parabola voltage, and the overlapped resonance voltage and the horizontal parabola. After stepping up the voltage, the superimposed with the DC focus voltage generated by the flyback transformer unit 14, the horizontal dynamic focus voltage of the horizontal parabola type is corrected to the aspherical area of the CRT panel on the dynamic focus electrode of the CRT. A horizontal dynamic focus circuit composed of an applied dynamic focus transformer section (17). The horizontal dynamic focus voltage correction circuit section (16) is provided with a coil (L17) and a capacitor (C15), which are parallel resonance circuits for generating a resonance voltage at a frequency multiple of the horizontal parabola voltage. And a capacitor (C12) of the waveform shaping circuit section (15) and a capacitor (C15) of the horizontal dynamic focus voltage correction circuit section (16) to be superimposed on the capacitor (C14). In horizontal deflection circuit where deflection and high pressure are separated. A horizontal dynamic focus voltage correction circuit 16 for extracting the parabola voltage from the S-shaped correction capacitor Cs11 of the horizontal output circuit unit 13 and superimposing the parabola voltage with the parallel resonance voltage, and a correction voltage superimposed with the parallel resonance voltage. Is a horizontal dynamic focusing circuit comprising a dynamic focus transformer section (17) for inverting and boosting the voltage to a high voltage and superimposing the DC focus voltage of the flyback transformer section (14) to the dynamic focus electrode of the CRT.