KR800000900Y1 - Deflection Distortion Correction Circuit - Google Patents

Abstract

No content.

Description

Deflection Distortion Correction Circuit

1 to 3 are views showing a state of crushed by the upper and lower pincushion.

4 to 6 each show one connection diagram of the inventive circuit.

7 and 8 are waveform diagrams for the explanation thereof.

The screen of the television receiver is crushed with pincushion up and down as shown in FIGS. 1 to 3 with the wide angle of the CRT. 1 is a case where dents are generated vertically and symmetrically, and FIGS. 2 and 3 are cases where asymmetrically occurs.

Such deflection distortion can be corrected by superimposing a correction signal suitable for the vertical deflection sawtooth wave.

The present invention provides a deflection distortion correction circuit that can reliably obtain a signal for correction in accordance with a distorted aspect by a simple configuration, and thus can reliably correct a deflection distortion as shown in the drawing. It will be described based on the drawings.

In the example of FIG. 4, (1) and (2) are first and second transistors and the controlled electrodes thereof, i.e., emitters, are the output electrodes of the third and fourth transistors 3 and 4, i.e. It is connected to the collector, respectively, and is connected to a common load resistor 7 through separate PN junctions, that is, via diodes 5 and 6 in the example of the figure, respectively. For example, the variable DC power supply 8 is connected to the control electrode of the second transistor 2, that is, the base, and, for example, the control electrode of the first transistor 1, that is, the base of FIG. Supply vertical sawtooth SA as shown in FIG. On the other hand, the controlled electrodes of the third and fourth transistors 3 and 4, i.e., the emitters, are connected in common and the constant current source 9 is connected to the connection points, for example, to control the third transistor 3. A horizontal pulse as shown in FIG. 7A, that is, a horizontal synchronous signal SH, is supplied to an electrode, that is, a base, and a suitable voltage is applied to a control electrode of the fourth transistor 4, that is, a base by a power supply 10. The third and fourth transistors 3 and 4 are differentially switched by this horizontal pulse SH. In addition, a capacitor 13 for removing the sawtooth wave component of 60 Hz through the base and emitter of the transistor 12, that is, the connection point between the diodes 5 and 6 and the load resistor 7, The terminal 15 is derived from the circuit 14 by connecting to the resonance circuit 14 whose resonance frequency is equal to the horizontal frequency. According to this circuit, in the section of the horizontal pulse SH, the third transistor 3 is turned "on" and the fourth transistor 4 is turned "off", so that the load resistor 7 is performed. Current flows through the diode 5 and the transistor 3 so that the diode 5 is "on" and therefore the first transistor 1 is "on". Therefore, in this section, the vertical sawtooth wave SA supplied to the base of the transistor 1 is switched to appear in the output terminal 11. On the other hand, in the section between the horizontal pulses SH, the fourth transistor 4 is turned "on" and the third transistor 3 is turned "off", so that the load resistor 7, the diode 6 and the transistor 4 are turned off. The current flows through the diode 6 to turn on, and the second transistor 2 is turned on. Thus, for example, if the deflection distortion occurs vertically and symmetrically as in the first degree, the DC voltage E ₀ is adjusted in advance so that the DC voltage E ₀ equal to the average value of the vertical sawtooth SA is obtained as shown in FIG. 7A. As a result, the DC voltage E ₀ is switched to appear in the terminal 11 in the interval between the horizontal pulses SH. Therefore, the terminal 11 eventually obtains a pulse signal P ₀ as shown in FIG. 7B in this case. The pulse signal P ₀ is transmitted through the transistor 12 and through the condenser 13 to remove the sawtooth wave component at 60 Hz. Thus, as shown in FIG. 7C, one cycle is performed in one horizontal period from the resonant circuit 14. As the corresponding sine wave, the amplitude becomes zero at the time of the middle of the vertical section, and a signal S _{0 which} is increased as it moves away from it is obtained.

Accordingly, the signal S ₀ is superimposed on the vertical sawtooth SA at the synthesizer 16 with the proper polarity and the jingle state, so that the value of the signal S ₀ is roughly changed in the horizontal section TH in the horizontal section TH as shown in FIG. In addition, a corrected vertical sawtooth deflection signal, which is increased as the change is far from the middle of the vertical section, is obtained, so that deflection distortion equal to the first degree can be corrected by flowing it into the vertical deflection coil.

If the deflection distortion becomes larger at the bottom of the screen as shown in FIG. 2, the variable DC power supply 8 is adjusted to thereby obtain a voltage E ₁ larger than the above-described voltage E ₀ as shown in FIG. 7A. Turn it off. Thus, in the interval between the horizontal pulses SH, this voltage E ₁ is switched to the gate, so that the terminal 11 obtains the pulse signal P ₁ as shown in FIG. The signal S ₁ which becomes 0 at the half time point is obtained. Therefore, the corrected vertical sawtooth wave deflection signal obtained at the output stage 17 also corresponds to the signal S ₁ , so that deflection distortion similar to the second degree can be corrected. When the deflection distortion increases in the upper side of the screen as shown in Fig. 3, on the contrary, a voltage smaller than the voltage E ₀ may be obtained in the variable DC power supply 8.

In the example of FIG. 5, transistors 18 and 19 are provided in place of diodes 5 and 6 of the example of FIG. 4, and emitters of transistors 1 and 2 are replaced by transistors 18 and ( This is a case where the collectors of the transistors 18 and 19 are grounded by connecting them to a common load resistor 7 through the base and the emitter of 19). Also in this example, the deflection distortion can be corrected by the same operation as in the example of FIG.

In the example of FIG. 6, the resistors 20 and 21 are connected to the emitter side of the first and second transistors 1 and 2, respectively, and the constant current source 9 is connected to the third and fourth This is the case where the emitter side of the transistors 3 and 4 is connected between the power supply. In this example, in the section of the horizontal pulse SH, the transistor 3 is "off" and the transistor 4 is "on", so the transistors 1 and 18 are "on", and the transistors 2 and (19) is " off " and as described above, the vertical sawtooth SA is switched and the transistor 3 is " on " and the transistor 4 is " off " The transistors 2 and 19 are turned "on", and the voltage from the power supply 8 is switched gate as described above. Therefore, also in this example, deflection distortion can be corrected by the operation | movement similar to the above-mentioned example.

According to the above-described invention, the vertical sawtooth wave deflection signal reliably obtained in accordance with the correction signal according to the aspect of the vertical pincushion dent can be reliably obtained by the simple configuration of installing only a transistor, a diode, or a variable DC power supply for adjustment. Distortion can be reliably corrected.

The variable DC power supply 8 for adjustment may be connected to the base of the first transistor 1 for supplying the vertical sawtooth wave SA. In this case, a fixed voltage is supplied to the base of the second transistor 2. It goes without saying that the "on" and "off" relations of the third and fourth transistors 3 and 4 with respect to the horizontal pulse SH may be reversed from the examples described above.

In addition, a field effect transistor may be used as the first to fourth transistors (1) to (4).

Claims (1)

As shown in the figure and described above in the text, the controlled electrodes of the first and second transistors are connected to the output electrodes of the third and fourth transistors, respectively, and simultaneously connected to a common load through separate PN junctions. The variable DC power supply is connected to the control electrode of the first or second transistor, and the vertical sawtooth wave is supplied to the control electrode of the first transistor so that the third and fourth transistors are connected by a horizontal pulse. A deflection distortion correction circuit which performs a differential switching operation and obtains a signal for correcting vertical pincushion distortion from the load.