JPH0352056Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a left-right pink distortion correction circuit suitable for use in, for example, television receivers.

[Summary of the idea]

This idea is to supply the rectified output of the flyback transformer to the differentiating circuit in the left and right pink-cushion distortion correction circuit, and to obtain a correction signal by superimposing the output of this differentiator circuit on a parabolic wave signal with a vertical period. By supplying the signal to the distortion correction circuit, it is possible to correct pink distortion in areas that could not be corrected in the past, especially in the upper corners of the screen.

[Conventional technology]

In conventional in-line color picture tubes,
It is known that both sides are distorted into a pincushion shape, as shown in FIG. 3A.

Therefore, in order to correct the left and right pink coupling distortion, the sawtooth wave current flowing through the vertical deflection coil is converted into a voltage and integrated, and the sawtooth wave voltage is obtained by integrating the sawtooth wave voltage with the parabolic wave voltage obtained by integrating it with an S-shaped capacitor. The left and right pink distortion distortion is corrected by amplitude modulating the horizontal deflection current using a parabolic wave signal obtained by subtracting the horizontal deflection current. For example, as a pink distortion correction circuit, a configuration is known in which the power supply voltage of a horizontal output circuit is modulated by the above-mentioned parabolic wave signal, as shown in Japanese Utility Model Publication No. 60-17969.

[Problem that the invention attempts to solve]

However, in the conventional left and right pink friction distortion correction circuit, it is not possible to form a parabolic wave signal that enables complete correction. There was a drawback.

Therefore, the purpose of this invention is to provide a left-right pink distortion correction circuit that can correct left-right pink distortion distortion, including parts that could not be corrected in the past, by transforming a parabolic wave signal using a very simple circuit. It's about doing.

[Means for solving problems]

This idea is based on vertical deflection circuits 7, 9, 10, 11.
The rectified output of the output signal of the flyback transformer 1 that is supplied to the main body is differentiated, and this differentiated output is superimposed on a parabolic waveform with a vertical period to obtain a correction signal, and the left and right pink coupling distortion is corrected by the correction signal. It features a left and right pink distortion correction circuit.

[Operation] The level of the rectified output supplied to the vertical deflection circuit decreases in the first half of vertical scanning. By differentiating this level drop portion with the differentiating circuit 4, a negative correction signal can be obtained only at the start end of vertical scanning. The differential signal of this rectified output and the parabolic wave signal are superimposed to generate a parabolic wave signal in which the starting end section of the vertical period falls sharply, and this modified parabolic wave signal is used as a signal for correcting left and right pink distortion distortion. .

〔Example〕

An embodiment of this invention will be described below with reference to the drawings. FIG. 1 shows the structure of an embodiment of this invention, and in FIG. 1, numeral 1 indicates a flyback transformer. 1a is the primary coil of the flyback transformer 1, 1b, 1
c and 1d are secondary coils of the flyback transformer 1, respectively.

A rectifier circuit consisting of a diode 2 and a capacitor 3 is connected to the secondary coil 1b of the flyback transformer 1, and a diode 20 is connected to the secondary coil 1c.
A rectifier circuit consisting of a diode 23 and a capacitor 24 is connected to the secondary coil 1d. A DC voltage of a predetermined level generated at each of the output terminals 22 and 25 of the rectifier circuit is used as the power supply voltage.

Further, an output terminal 7a of a rectifier circuit including a diode 2 and a capacitor 3 is connected to a power supply terminal of a vertical output circuit 7. The vertical output circuit 7 is, for example,
It has an SRPP (Shunt regulated push pull) configuration, and a sawtooth wave signal with a vertical period formed by a vertical oscillation circuit and an amplification/shaping circuit (not shown) is supplied from the input terminal 8. One end of the vertical deflection coil 9 is connected to the output terminal of the vertical output circuit 7, and the other end of the vertical deflection coil 9 is grounded via an S-shaped capacitor 10 and a resistor 11 in series.

The vertical output circuit 7 charges the S-shaped capacitor 10 via the vertical deflection coil 9 during the first half period when the vertically periodic sawtooth signal from the input terminal 8 exceeds a predetermined level, and also charges the vertically periodic sawtooth signal from the input terminal 8. In the second half period when the wave signal is below a predetermined level, the charges accumulated in the S-shaped capacitor 10 are discharged via the vertical deflection coil 9, and a vertical deflection current is supplied to the vertical deflection coil 9.

A connection point (shown in FIG. 1) between a diode 2 and a capacitor 3 constituting a rectifier circuit is connected to an input terminal of a differentiating circuit 4 consisting of a capacitor and a resistor. An output terminal of the differentiating circuit 4 is connected to one end of a coupling capacitor 6 via a variable resistor 5 for level adjustment. Vertical deflection coil 9 and S-shaped capacitor 10
The connection point (shown in FIG. 1) is connected to the other end of the capacitor 6 via a resistor 12.

A connection point between capacitor 6 and resistor 12 (shown in FIG. 1) is connected to an input terminal of amplifier circuit 13.

The output terminal of the amplifier circuit 13 is grounded via the primary coil 14a of the pink coupling transformer 14. One end of the secondary coil 14b of the pink coupling transformer 14 is supplied with a horizontally periodic sawtooth wave signal supplied from a horizontal output circuit via a terminal 15. Further, one end of the horizontal deflection coil 16 is connected to the other end of the secondary coil 14b of the pink coupling transformer 14, and the other end of the horizontal deflection coil 16 is grounded.

The signals of each part in this embodiment are shown in Fig. 2A.
~D. During the first half of the vertical cycle, which corresponds to the upper half of the screen due to the operation of the vertical output circuit 7, a load current flows through the vertical deflection coil 9 in the direction of the arrow in the figure. Further, in the latter half of the vertical cycle, which is the lower half of the screen, the discharge current of the S-shaped capacitor 10 flows through the vertical deflection coil 9 in the direction opposite to the arrow in the figure.

Therefore, at the connection point between the diode 2 and the capacitor 3, a signal shown in FIG. 2A is generated whose voltage level decreases in the first half of the vertical period. This signal is supplied to the input terminal of the differentiating circuit 4.

The signal shown in FIG. 2A is differentiated in the differentiating circuit 4, and the output terminal of the differentiating circuit 4 receives a signal whose voltage level drops sharply at the start of vertical scanning, as shown in FIG. 2B. occurs. This differential signal is brought to an appropriate level by passing through a variable resistor 5, and is supplied to one end of a coupling capacitor 6.

Also, vertical deflection coil 9 and S-shaped capacitor 1
At the connection point 0, a parabolic wave signal with a vertical period shown in FIG. 2C is generated. This parabolic wave signal is supplied to the other end of the coupling capacitor 6 via the resistor 12.

Both the differential signal from the differentiating circuit 4, which has been set to an appropriate level by the variable resistor 5, and the vertically periodic parabolic wave signal shown in FIG. , a parabolic wave signal as shown in FIG. 2D is generated in which the starting end section of the vertical period drops sharply. This second
The parabolic wave signal shown in FIG.
is supplied to

Secondary coil 1 of pink union transformer 14
4b is supplied with a horizontal deflection current from the terminal 15, the horizontal deflection current is amplitude-modulated with the change in the parabolic wave signal shown in FIG. 2D supplied to the primary coil 14a, and this An amplitude modulated horizontal deflection current is supplied to horizontal deflection coil 16 .

Therefore, the parabolic wave signal in which the starting end section of the vertical period drops sharply corrects the left and right pink distortion distortion, and especially the distortion at the upper corner of the screen.

Incidentally, as the left and right pink distortion correction circuit, a configuration that modulates the power supply voltage of the horizontal output circuit may be used.

[Effect of idea]

In this device, the rectified output supplied to the vertical deflection circuit is differentiated by a differentiating circuit, and this differentiated signal is superimposed on a parabolic wave signal with a vertical period, resulting in a parabolic wave signal in which the starting end section of the vertical period falls sharply. is obtained, and this modified parabolic wave signal is used as a signal for correcting left and right pink distortion distortion.

Therefore, according to this invention, by using a very simple circuit, it is possible to correct left and right pink distortion including distortion at the upper corner of the screen, which has hitherto been considered impossible to correct.

[Brief explanation of drawings]

Fig. 1 is a connection diagram of an embodiment of this invention, Fig. 2 is a schematic diagram used to explain the signals of each part in an embodiment of this invention, and Fig. 3 is a schematic diagram used to explain left and right pink tension distortion. It is. Explanation of main symbols in the drawings: 1: flyback transformer, 2: rectifier diode, 3: smoothing capacitor, 4: differential circuit, 5: variable resistor for adjustment, 6: coupling capacitor, 7: vertical output circuit,
9: Vertical deflection coil, 10: S-shaped capacitor, 1
4: Pink union transformer, 16: Horizontal deflection coil.

Claims (1)

[Scope of utility model registration request] The rectified output of the output signal of the flyback transformer supplied to the vertical deflection circuit is differentiated, and this differentiated output is superimposed on the parabolic waveform of the vertical period to obtain a correction signal, and the left and right pink distortion distortion is corrected by the correction signal. The left and right pink tension distortion correction circuit is characterized by: