JPS6211388A - Digital convergence device - Google Patents

Abstract

PURPOSE:To attain highly adjusting of convergence with small capacity of a memory by setting adjusting points even for a signal specification of different aspect ratio according to its aspect ratio and by reading out a correction data correspondent to the location of the adjusting point. CONSTITUTION:An input signal is supplied to an aspect detector part 19 and the aspect is detected, and the detection signal is supplied to an adjusting point setting part 20 to set adjusting points in number corresponding to the aspect. Using the signal from the part 20, a write address control part 8, a read address control part 5, and an interpolation processing part in vertical-direction 13 are controlled in order to read out from a 1-frame memory 10 a convergence correction amount correspondent to the aspect ratio. Therefore, if the aspect ratio of a picture is changed from 4:3 to 5:3, eleven adjusting points in vertical direction are set. For these adjusting points, the correction data written beforehand in the 1-frame memory 10 is read out, and a correction waveform corresponding to the eleven adjusting points is outputted from a D/A 14. Accordingly, if the aspect changes, the convergence adjusting is accomplished with 1-frame memory 10 of one plane.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a device for correcting the convergence of a color television receiver, and provides a digital convergence system that can be adjusted with high precision and can sufficiently handle objects with different aspect ratios. It is related to equipment.

Conventional technology Generally, color television receivers have red and green.

An image is created by combining the three colors of blue on a fluorescent surface or a projected screen, but in this case, accurately aligning the three colors, that is, convergence adjustment, is an important issue that affects image quality. become.

Here, the convergence deviation will be explained using a projection type color television receiver as an example.

In FIG. 6, 1 indicates a projection screen for projecting images. 2, 3. 4 is a projection type picture tube equipped with an optical lens that forms the image obtained on the fluorescent surface onto the projection screen 1, and each fluorescent surface has images of three colors of red, green, and blue. is obtained. When these picture tubes are arranged horizontally as shown in Figure 5, the projection angles relative to the projection screen 1 are different, so the projected raster will be misaligned for each color as shown in Figure 6. . In FIG. 6, a solid line 3° C. indicates a raster projected by the picture tube 3 for green light, a broken line 41 indicates a raster projected by the picture tube 4 for blue light, and a dashed line 2β indicates a raster projected by the picture tube 2 for red light. To correct this positional shift, a convergence adjustment coil is installed in the projection picture tube 2, 3.4 separately from the main deflection yoke, and the sawtooth wave current in the horizontal scanning period is amplitude-modulated in the vertical period. The amplitude can be adjusted independently. However, the amount of color shift varies due to variations in the mounting position of each picture tube, variations in the configuration of the optical lens system, variations in the projection screen position, etc., so in order to perform highly accurate convergence adjustment, a simple sawtooth waveform This is not possible with electric currents or combinations of parabolic currents.

As a method for realizing such convergence adjustment, a convergence circuit having a digital correction waveform forming section has been considered.

The conventional digital convergence device will be explained in detail below with reference to FIG.

Horizontal and vertical periodic pulses synchronized with the deflection current period are applied as synchronization signals, thereby driving the read address control unit 6. The pulse from the read address control section 6 is used to drive the crosshatch pattern generator 6 to project a crosshatch pattern on the projection screen. On the other hand, with the address key on the control panel 12,
A cross point at a position requiring convergence correction is designated, and a position address is set in the write address control unit 8. Next, using the data write key of the color to be corrected, for example, red provided on the control panel 12, write the correction amount into the one frame memory 1o through the data reversible counter 11 while looking at the screen. Normally, the multiplexer 9 performs switching control such that writing into the one-frame memory is performed during the blanking period of the video signal.

Therefore, reading is not impaired. Similar operations are performed at each adjustment point as described above.

Next, the reading of one frame memory is performed by the read address control section 6 through the register 18 driven by the address control section 6 between each crosshatch on the screen. That is, the correction amount for each scanning line for which no correction amount is stored is determined by linear approximation, for example. Next, the output signal is converted into an analog quantity by a D/A converter 14. Next, the correction amount in the horizontal direction is smoothed through a low-pass filter (LPF) 1es, and a correction current is applied to the output amplification section 16 and supplied to the convergence coil 17. Convergence adjustment at each adjustment point is performed as described above.

Problems to be Solved by the Invention However, in the above configuration, since the one frame memory 10 is a one-sided memory, if the aspect ratio is different, the positions of the cross points of the cross hatch pattern displayed on the entire screen will change. However, there was a problem in that convergence adjustment could not be performed with high precision. Another problem is that the one-frame memory 10 needs to have two sides of memory in order to accurately perform convergence adjustment even for objects with different aspect ratios.

In view of this, it is an object of the present invention to provide a digital convergence device that can sufficiently handle signal specifications with different aspect ratios using a single memory.

Means for Solving the Problems The present invention provides a detecting means for detecting signals with different aspect ratios, a setting means for setting an adjustment point corresponding to the aspect ratio based on the signal from the detecting means, and an adjustment point set by the setting means. The present invention is a digital convergence device comprising a readout means for controlling the address of a storage element corresponding to the adjusted adjustment point position and reading out a convergence correction amount corresponding to the aspect ratio.

According to the above-described configuration, the present invention sets an adjustment point according to the aspect ratio even for signal specifications with different aspect ratios, and reads out correction data corresponding to the position of the adjustment point. That is, the memory capacity is small and convergence adjustment can be performed with high precision.

Embodiment FIG. 1 shows a block diagram of a digital convergence device according to a first embodiment of the present invention. Components in FIG. 1 that operate in the same way as in FIG. 7 are designated by the same numbers and their explanations will be omitted. In FIG. 1, reference numeral 19 denotes an aspect detection section 20 that detects an aspect ratio from an input signal, and an adjustment point setting section that sets an adjustment point corresponding to the aspect ratio based on a detection signal from the aspect detection section 19. A signal from the adjustment point setting section 20 controls the write address control section 8, the read address control section 6, the vertical interpolation processing section 13, etc., and reads out the convergence correction amount corresponding to the aspect ratio from the one frame memory 1o. ing. In order to explain the operation of the digital convergence device of this embodiment configured as described above, the screen diagram of FIG. 2 and the waveform diagram of FIG. 3 will be used below.

A synchronization signal synchronized with the deflection current cycle is applied, thereby driving the read address control section 5.

Using the pulses from the read address control section 5, the crosshatch pattern generator 6 is driven, and as shown in FIG. Projects 13 crosshatch patterns in the vertical direction. Adjustment point D1 shown in Figure 2a
Correction data v1 to D13 are written into the one frame memory 1o as shown in FIG. Third
The correction waveform corresponding to adjustment points D1 to D13 in the figure is D/
It is output from A14. Next, when the signal has an aspect ratio of 6:3, the aspect is controlled by decreasing the vertical amplitude, for example, as shown in FIG. At this time, conventionally, even if the vertical amplitude changes, the various address systems operate the same as in the case of aspect ratio 4:3 shown in Figure 2a. Adjustment points D1 to D13 are set on the screen. Adjustment points D1 to D13 in Figure 2C
The correction data v1 to 13 are the same as the adjustment points D1 to D14 shown in FIG. 2, and the correction waveform shown in FIG. 3d is output from the D/A 14. Therefore, since correction data corresponding to the aspect, that is, the spatial position of the screen is not output, it goes without saying that misconvergence occurs as you move from the center of the screen to the outside of the screen.

Therefore, in the present invention, an input signal is supplied to the aspect detection section 19 to detect the aspect, and this detection signal is supplied to the adjustment point setting section 2o to set the aspect, that is, the number of adjustment points corresponding to the spatial position of the screen. It is set. In response to a signal from the adjustment point setting section 2o, the write Azores control section 8, the read address control section 5, and the vertical interpolation processing section 1
3, the convergence correction amount corresponding to the aspect ratio is read out from the one frame memory 1o. Therefore, the screen with an aspect ratio of 4:3 shown in Figure 2a,
When the aspect ratio is set to 6:3, 11 adjustment points (D2 to D12) in the vertical direction are set as shown in FIG. 2C. From the adjustment points D2 to DI2 shown in FIG. 2C, the correction data v to vl stored in the one frame memory 10 in advance are read out, and as shown in FIG. The correction waveform corresponding to DI2 from adjustment point D2 is D/A14.
is output from. Therefore, since adjustment points and correction data corresponding to the aspect, that is, the spatial position of the screen, are read out, even if the aspect changes, convergence adjustment can be performed with high accuracy using one frame memory 10 on one screen.

Next, the reading and writing of one frame memory 1o are the same as conventional operations, so the explanation will be omitted.0 As described above, according to this embodiment, the aspect detection section 19 that detects the aspect ratio of the signal, and the An adjustment point setting section 20 is provided for setting an adjustment point according to the shear aspect ratio according to a signal, and the aspect ratio can be adjusted by controlling various address systems etc. using the signal from the adjustment point setting section 2o. Since the spatial adjustment point and correction amount are always the same even for different signal specifications, convergence adjustment can be performed with high precision using a single memory.

FIG. 4 shows a specific circuit configuration of the present invention. In FIG. 4, parts that operate in the same way as in FIG. 1 are designated by the same numbers and their explanations will be omitted. Here, to simplify the explanation, a case where the aspect changes depending on the horizontal scanning frequency will be described. In FIG. 4, 21 is a horizontal scanning frequency detection section, 22 is a coefficient setting section, 23 is a vertical adjustment point processing section, and 24 is an LPF.
It is.

Here, as a means for detecting a difference in aspect ratio, for example, a horizontal scanning frequency detection section 2 that detects a horizontal scanning frequency is used.
1, an adjustment point setting section 2o and a coefficient setting section 2 which set the number of adjustment points in the vertical direction and their coefficients based on the detected signal.
2, a vertical adjustment point inter-point processing unit 23 which calculates a convergence correction amount between adjustment points from the difference between the correction amounts of upper and lower adjustment points, the set number of adjustment points and a coefficient, and a horizontal correction amount. LPF 24 whose cutoff frequency can be controlled by the detected signal.
It is coupled with.

The horizontal scanning frequency detection section 21 is composed of a counter, etc., detects the horizontal scanning frequency, and supplies the detected horizontal scanning frequency to the adjustment point setting section 20° coefficient setting section 22, LPF 24, write address control section 8, and read address control section 6. Various address control sections generate address signals corresponding to horizontal scanning frequencies based on signals from the horizontal scanning frequency detection section 21.

The adjustment point setting section 2o and the coefficient setting section 22 set the adjustment point number data and coefficient data written in advance according to the aspect ratio according to the signal from the horizontal scanning frequency detection section 21. There is. The adjustment point number data from the adjustment point setting section 2o and the coefficient data from the coefficient setting section 22 are supplied to the vertical adjustment point processing section 23. The vertical adjustment point processing unit 23 calculates the convergence correction amount between the adjustment points for each scanning line between the adjustment points based on the difference between the correction amounts of the upper and lower adjustment points, and the set adjustment point number data and coefficient data. The amount of correction is calculated. The correction amount corresponding to each horizontal scanning frequency is smoothed by an LPF 24, such as an active filter, whose cutoff frequency can be controlled by a signal from the horizontal scanning frequency detection section 21. Writing and reading of one frame memory 1o is as follows:
Various addresses are controlled by signals from the adjustment point setting section 2o, and correction data is written or read out at adjustment points corresponding to the aspect, that is, the spatial position of the screen. Since the following operation is the same as the conventional one, the explanation will be omitted.

In the first embodiment, the aspect has been described with respect to a change in the raster amplitude in the vertical direction, but it goes without saying that the same applies to a change in the raster amplitude in the horizontal direction.

Further, in the first embodiment, the aspect detection unit 19
Although the horizontal scanning frequency of the synchronization signal is detected, the number of scanning lines may also be detected, or aspect information may be superimposed on the signal and the signal may be detected for discrimination.

As described in detail, according to the present invention, the adjustment point B and the correction amount always exist at the same position on the screen even for signal specifications with different aspect ratios, so the memory capacity is small and the accuracy is improved. The convergence can be adjusted well, and its practical effects are great.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a digital convergence device according to an embodiment of the present invention, Fig. 2 is a screen diagram showing the operation of the same embodiment, Fig. 3 is an operation waveform diagram of the embodiment, and Fig. 4 is the same embodiment. 6 is a block diagram showing the principle of a projection type color television receiver, FIG. 6 is a diagram illustrating the convergence deviation, and FIG. 7 is a block diagram of a conventional digital convergence device. It is a diagram. 8...Write address section, 6...Read address section, 6...Cross hatch generator, 10...1 frame memory, 19...Aspect Detection section, 2o...Adjustment point setting section, 13
...Vertical interpolation processing section. Name of agent: Patent attorney Toshio Nakao and 1 other person (Ashe 6 Kut 5.° 3 no (A 0 Kut 5° 3) Figure 3, Figure 5, Figure 6

Claims (1)

[Claims] a display 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; an input means for inputting position information of the adjustment points; and a digital display means for inputting the convergence correction amount for the adjustment points. a storage means for storing the aspect ratio; a detection means for detecting the aspect ratio from a signal input to the receiver; and a setting means for setting an adjustment point corresponding to the aspect ratio based on the signal from the detection means; A digital convergence device comprising: reading means for controlling an address of a storage element corresponding to an adjustment point position set by a setting means and reading a convergence correction amount corresponding to an aspect ratio.