JPS6110385A - Digital convergence device - Google Patents

Abstract

PURPOSE:To attain ease of R, G convergence adjustment by operating convergence correction data of R in interlocking with that of G. CONSTITUTION:The convergence adjusting point is designated by a digital convergence circuit 18, the convergence correction data of each adjusting point for the R-G amplifier and the R-G differential amplifier is written in one frame memory, and the output signal for read convergence correction is outputted from the memory. The R, G correction amount generating circuit 19 generates the R, G convergence correction waveform by receiving its output signal.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a device for correcting convergence and < of a color television receiver, and more particularly to a digital convergence device that can be adjusted accurately and easily.

Conventional Structure and Problems In the 7-yado mask system color picture tube used in general color television receivers, color shift occurs because the radius of curvature of the shadow mask from the center of deflection is larger than the radius of curvature of the shadow mask. Furthermore, in three projection-type color receivers that emit light in three primary colors, the angle of incidence of the picture tube with respect to the screen differs for each picture tube, resulting in color shift on the screen. For the superposition of these three primary colors, so-called convergence, an analog method is used to obtain a convergence correction waveform from a horizontal flyback pulse and a vertical waveform using passive elements such as coils, capacitors, and resistors, but the convergence accuracy However, there are some drawbacks that are not very good. As a means for performing highly accurate convergence over the entire screen, for example, as shown in US Pat. No. 3,943,279 FJA#I, a means for digitally performing convergence correction has been proposed.

A conventional digital convergence device for a picture receiver using a picture tube with a delta type electron gun arrangement will be described below. The concept will be explained based on the block diagram in Figure 1, and the concept is that a convergence correction pattern such as a grid pattern is projected on the screen, and the data of the convergence correction amount for each grid point is digitally stored in one frame memory. This information is read out, D/A converted, and convergence correction is performed. Figure 1 below,
This will be explained in more detail using FIG. First, as shown in FIG. 2, a grid pattern of, for example, 9 columns in the horizontal direction and 7 rows in the vertical direction is displayed on the screen K by the video signal generating circuit 15.
Select the grid point where you want to correct using the cursor keys on control panel 1. Grid points selected using the cursor keys (
The address (hereinafter referred to as adjustment point) is stored in the cursor counter 12. Next, when you specify the color you want to correct, for example red using the write key on the control panel 1, the contents of the 1 frame memory 3 selected using the cursor key and the write key are read into the data reversible counter 2, and then press the write key. Write correction is performed by continuing to operate and increasing/decreasing the data reversible counter 2. Thereafter, write corrections are made for all adjustment points in the same manner.

Next, reading out the convergence correction amount written in the one-frame memory 3 will be explained. Since the one-frame memory 3 stores only the correction amount at the location corresponding to the adjustment point, it is necessary to perform interpolation for each scanning line between adjustment points in the vertical direction. Therefore, for example, after reading the correction amount of the adjustment point in the first row from the 1-frame memory 3 and setting it in the 1H register 4,
Read the correction amount of the adjustment point in the row. In this way, using the correction amounts of the first and second lines read from the one-frame memory 3, the correction amount of the scanning line included between the adjustment points of the first and second lines can be calculated within a linear approximation. Find by insertion. That is, the difference between the amount of correction in the first line and the amount of correction in the second line is determined by the subtraction circuit 6, and the weighting coefficient for each scanning line written in advance in the coefficient ROM 7 is multiplied by the multiplication circuit 6. The result and the correction data in the second row are added together in an adder circuit 8 to perform interpolation. Next, the output signal of the adder circuit 8 is D/A
A converter 9 converts it into an analog quantity to obtain a stepped waveform signal. The signals between the adjustment points in the horizontal direction are smoothed by a low-pass filter 1o for the correction amount of the adjustment points in each row, amplified by an output circuit 16, and then supplied to a convergence yoke 17. The same applies to the other green, blue radials, and blue laterals.

As shown in Figure 3, the convergence shift in the mask-type color picture tube commonly used in color television receivers is caused by the distance from the center of deflection to the shadow mask plane even though the beam is concentrated at the center of the screen. Since the center and peripheral areas are different, the beam concentrates in front of the shadow mask in the peripheral area, and the convergence shift increases as the distance from the center of the screen increases.

Figure 4 shows the movement of each color during convergence correction. Red radial, green radial, blue radial, and blue lateral are corrected in the direction of the arrow in the figure, and R, G, and B overlap at the center 0 point, and convergence is achieved. Corrections are made.

However, in the above configuration, the radial movement of RG moves independently, so it is necessary to adjust the radial directions of R and G several times in order to overlap the R and G radial directions at the center 0 point. . Further, there is a problem in that it takes a considerable amount of adjustment time to perform precise convergence correction on the entire screen.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional problems, and aims to provide a digital convergence device that can be adjusted accurately and easily.

Structure of the Invention The present invention specifies a convergence adjustment point using a cursor key, writes convergence correction data for each adjustment point of an RG amplifier and an RG differential 7-lens-yield amplifier into a 1-frame memory, and reads it from the 1-frame memory. A digital convergence device comprising a digital convergence means for performing convergence correction, and a creation means for creating R and G convergence correction waveforms from the convergence correction data of the R-G amplifier and the R-G differential amplifier, By operating the convergence correction data of R and G in conjunction,
By performing convergence adjustment in the radial and lateral directions of another B at the intersection of R and G, convergence adjustment can be performed accurately in a short time.

DESCRIPTION OF EMBODIMENTS FIG. 5 shows a block diagram of a digital convergence device in a first embodiment of the present invention. 18 is a digital convergence circuit, 19 is an R, G correction amount creation circuit, 20, 21, 22° 23 is an output circuit, 28 is a convergence yoke, 24 is an R/radial dynamic winding, 25 is a G/radial dynamic winding line, 26
is a B-lateral dynamic winding, and 27 is a B-radial dynamic winding.

The operation of the digital convergence device of this embodiment configured as described above will be explained below.

Horizontal and vertical periodic pulses, synchronized to the deflection current period, are applied as synchronization signals, which cause the digital convergence circuit 18 to pass as described above. This digital convergence circuit 18 specifies the convergence adjustment point using the cursor keys, and connects the R-G amplifier and R-G amplifier.
Convergence correction data for each adjustment point of the G differential amplifier, B lateral, and B radial is written in one frame memory and read from the frame memory to perform convergence correction. Therefore, as an output from the digital convergence circuit 18, convergence correction data corresponding to the R-G amplifier, the R-G differential amplifier, the B lateral, and the B radial are read out. The convergence correction data of the R-G amplifier and the R-G differential amplifier from the digital convergence circuit 18 are R,
The correction data is supplied to the G correction fJ creation circuit 19, and correction data corresponding to the R radial and the G radial is created. Said R,
The H radial convergence correction data from the G correction amount creation circuit 19 is amplified by the output circuit 20 and drives the H radial dynamic winding of the convergence yoke 28 . Further, the G radial convergence correction data is amplified by the output circuit 21 and sent to the G radial dynamic winding 251[1. The B lateral and B radial convergence correction data from the digital convergence circuit 18 is amplified by the output circuit 22 and the output circuit 23, and the B lateral dynamic winding and the B radial dynamic winding of the convergence yoke 28 are amplified by the output circuit 22 and the output circuit 23. Driving 0 In order to explain the present invention in more detail, a diagram showing the movement of each color in convergence correction shown in FIG. 6 will be used.

When the convergence adjustment point is specified using the cursor keys included in the digital convergence circuit 18 and each grid point is arranged as shown in FIG. -G Day 27
A lential amplifier is designated, and the data reversible counter 2 is increased or decreased to perform write correction so that the G lattice point located at 3 becomes the same vertical position 2 as the H lattice point. Next, specify the R-Ci amplifier with the write key of control pile 1, increase or decrease the data reversible counter 2, and simultaneously set the H grid point located at ■ and the G grid point located at ■ at the center ■. Correct the writing so that they are in the same position, and overlap R and G. Next, specify the radial value of B using the write key on the control panel 1, increase or decrease the data reversible counter 2, and write the case ρ ton of B located at Correct the writing so that it is at the leverage position ■.Next, specify the lateral of B using the write key on the control panel 1, increase or decrease the data reversible counter 2, and write the lattice point of B located at ■ as the center. Write correction is performed so that the position (2) is reached, and R, G, and B overlap, and convergence correction can be performed.

Thereafter, write corrections are made for all adjustment points in the same manner.

Next, the block diagram of FIG. 7 will be used to explain the R and G correction amount creation circuit 19 in detail.

The convergence correction data of the R-G amplifier is supplied to the input terminal 33 in FIG. Ru. Analog signals from D/A 29 and 30 are o
The P amplifiers 31 and 32 convert the current into voltage, and at the same time, it is reprinted. The convergence correction data of the RG amplifier from the OP amplifier 31 is supplied to the input terminal (2) of the output circuit 2o through the resistor R1. ○The convergence correction data of the R-G differential amplifier from the P amplifier 32 is supplied to the input terminal (■) of the output circuit 20 through the resistor R2, and is added by the resistance matrix of the resistors R1 and R2.
radial convergence correction data is created.

Further, the RG amplifier convergence correction data, that is, the G radial convergence correction data from the OP amplifier 31 is supplied to the output circuit 21 through the resistor R3.

Amplified in the output circuit 20.21, R radial dynamic winding @24 and G radial dynamic winding 2
5 to perform convergence correction. Similarly, in Figure 7, the digital convergence circuit 181dM7
This is the same operation as in Figure a. The convergence correction data of the RG amplifier from the oP amplifier 31 is supplied to the input terminal (2) of the output circuit 2o through the resistor R4, and to the input terminal (2) of the output circuit 21 through the resistor R6.

○The convergence correction data of the R-G differential amplifier 32 from P77 is passed through the resistor R5 to the input terminal ○ of the output circuit 2o, and the input terminal of the output circuit 21■
supplied to Therefore, the H radial convergence correction data is created at the input stage of the output circuit 2o, and the G radial convergence correction data is created by the resistor R6 and R
7 resistance matrix.

Next, in order to explain the details of FIG. 7, the diagram of FIG. 8 showing the movement of convergence correction will be used.

Specify the convergence adjustment point using the cursor keys included in the digital convergence circuit 18 in FIG.
When each grid point is arranged as shown in the figure, specify the R-G differential amplifier with the write key on the control panel 1 in Figure 1, increase or decrease the data reversible counter 2, and Write correction is performed so that the H lattice point located at 2 and the G lattice point located at 2 are at the same vertical position, R is at the 2 position, and G is at the 2 position.

Next, specify the R-G amplifier using the write key on the control panel 1, increase or decrease the data reversible counter 2, and simultaneously set the H lattice point located at ■ and the G lattice point located at ■ at the center. Correct the writing so that it is in the position of ■, and
，! : Superimpose G and perform convergence correction.

As described above, the RG correction amount creation circuit 19 can be easily created using a resistance matrix and an input stage of an output circuit.

Although the LPF in the digital convergence circuit 18 is omitted, it goes without saying that this can be omitted if the overall frequency characteristics of the OP amplifier, output circuit, etc. are designed.

As described above, according to this embodiment, the R-G amplifier and the R-G
By creating correction waveforms for the H radial and the G radial from the convergence correction data of the differential amplifier, the R and G radials can be adjusted simultaneously, making the adjustment easy.

A second embodiment of the present invention will be described below with reference to the drawings.

FIG. 9 is a block diagram of a digital convergence device showing a second embodiment of the present invention.

In this figure, parts that operate in the same way as in FIG. 5 are designated by the same numbers and their explanations will be omitted. The difference from the configuration shown in FIG. 5 is that analog correction data is created by an analog convergence circuit 35, and convergence correction is performed using analog convergence correction data and digital convergence correction data.

The entire operation of the second embodiment of the gagetal convergence device constructed as described above will be explained below.

The RG correction amount creation circuit 19 is connected to the input terminal ■ of the output circuit 2o.
The input terminal θ is supplied with analog convergence correction data in which, for example, a vertical parabola is superimposed on a horizontal parabola from an analog convergence circuit 35. The output circuit 2o adds and amplifies the two correction data to drive the H radial dynamic winding 24. Similarly, the input terminal ○ of the output circuit 21 has, for example, a waveform in which a vertical parabola is superimposed on the horizontal parabola described above, and the input terminal O of the output circuit 22 has, for example, a horizontal sawtooth waveform.
For example, a horizontal parabolic waveform is supplied to the input terminal 0 of No. 3, and is added to the digital correction amount of each color to drive the dynamic winding of each color.

As described above, according to this embodiment, an analog convergence circuit for creating analog convergence correction data is provided, and by performing convergence correction by adding the digital comparator correction data and the analog convergence correction data, the analog Since it is possible to use coarse adjustment data and digital quantities as fine adjustment data, convergence adjustment becomes easy and misconvergence due to interpolation calculation of linear approximation between adjustment points is reduced.

Furthermore, since the amount of digital correction is small, and the amount of correction per pit can be reduced, it is possible to eliminate horizontal stripes in the Lasque due to discontinuity in the amount of correction in the vertical direction.

Furthermore, by manually adjusting the analog correction amount by cutting off the DC current, it is possible to balance the power consumption of the output circuit.

In the first embodiment, the RG supplementary correction creation circuit is performed using hardware, but it may also be performed using software of the CPU used in the digital convergence circuit.

Further, in the second embodiment, the analog correction amount is added at the input stage of the output circuit, but it goes without saying that it may be added at other locations.

Effects of the Invention The digital convergence device of the present invention C. Specify the convergence adjustment point with the cursor keys, R-G amplifier, !
:R-G7'' digital convergence means for writing convergence correction data for each adjustment point of the differential amplifier into a 1-frame memory, reading it from the 1-frame memory and performing convergence correction;
By providing a creation means for creating R and G convergence correction waveforms from the convergence correction data of the amplifier and the R-G7" if7renshal amplifier, R and G can be corrected in conjunction, making adjustment easier. be able to.

In addition, by performing correction using a combination of digital correction amount and analog correction amount, adjustment time can be shortened, and
Misconvergence due to interpolation calculation of linear approximation between adjustment points is reduced.

Furthermore, since the amount of digital correction is small and the amount of correction per bit can be reduced, it is possible to eliminate horizontal stripes in the raster due to discontinuity in the amount of correction in the vertical direction. Furthermore, by inputting the analog correction amount with DC cut, the power consumption of the output circuit can be balanced, which has a great practical effect.

[Brief explanation of drawings]

Figure 1 is a block diagram of a conventional digital convergence device, Figure 2 is a front view of a screen displaying a pattern, and Figure 3 is a block diagram of a conventional digital convergence device.
The figure is a front view of a screen showing a convergence shift, FIG. 4 is a front view of a screen displaying a grid point pattern to explain the conventional example, and FIG. Block diagram, Figure 6 is the first
FIG. 7 is a configuration diagram for explaining the first embodiment in more detail, and FIG. 8 is a front view of a screen displaying a grid point pattern to explain the first embodiment. FIG. 9 is a front view of the screen displaying the lattice point pattern, and is a block diagram of the digital convergence device in the second embodiment of the present invention. G correction amount creation circuit, 2
0, 21, 22.23...output circuit, 28.
・Convergence yoke, 35・ Analog convergence circuit. Figure 2 (Q) Figure 3 Figure 4 Ringu Tatami Ward 9 Figure 6? Figure 7 Me Figure 8

Claims (1)

[Claims] Means for generating and displaying a plurality of convergence adjustment points in the horizontal and vertical directions on the screen of a color television receiver using a color picture tube of a shadow mask type, means for inputting position information of the adjustment points, and the adjustment means for storing the convergence correction amount of the RG amplifier and the convergence correction amount of the RG differential amplifier with respect to the point;
means for reading out the stored convergence correction amount of the R-G amplifier and the convergence correction amount of the R-G differential amplifier; A digital convergence device comprising means for creating a G convergence correction amount.