KR19980061402A - Digital convergence correction method and device - Google Patents

Abstract

The present invention provides a first process of storing horizontal convergence correction data for a previous screen, and calculating a horizontal convergence correction data for a current screen according to a correction request based on previously stored reference interpolation data when a correction request signal is input. And a third process of calculating vertical convergence correction data based on horizontal convergence correction data for the previous screen stored through the first process before the operation is completed through the second process, and A fourth process for calculating the vertical convergence correction data on the basis of the horizontal convergence correction data for the current screen when the operation is completed through the second process, and relates to a convergence correction method and apparatus therefor, in the projection TV Perform convergence correction using a hardware method, but increase the processing speed. Increase manufacturing costs, reduce manufacturing costs, and simplify system configuration.

Description

Digital convergence correction method and device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection TV, and more particularly, to a digital convergence correction method and apparatus for real-time processing of a correction request signal such as mode switching, power on, and convergence correction at an arbitrary point.

In general, modern people tend to spend a lot of time on leisure, especially the focus on communal life with family. In addition to these phenomena, as the life improved, I felt the desire to enjoy large screens such as theaters even when I watch TV or VTR at home.

A technology proposed to satisfy the needs of general users who desire a large screen as described above is a projection TV of projecting the image shown in FIG.

1 shows a structure of a rear projection type projection monitor, which is a front view and a side view.

Referring to the image display method of the projection TV shown in FIG. 1, a full color image is realized by forming an image on the same point of the screen by enlarging and projecting each individual image into three primary colors of light, red, blue, and green. to be.

That is, each image from the red-only CRT (R), the green-only CRT (G), and the blue-only CRT (B) is reflected by the mirror (M) and then merged on the screen (S) to have one full color image. 1, each of which has different spatial positions in the CRTs R, G, and B shown in FIG. 1 and has a Convergence Angle, that is, an angle at which the projected image is incident on the screen S. Since different, as shown in the accompanying FIG. 2, miss-convergence occurs.

Therefore, by applying an appropriate correction current in the horizontal / vertical direction to the convergence yokes of each of the CRTs R, G, and B, the mis-convergence should be corrected by adjusting the path of the electron beam. The adjustment flow of miss-convergence as shown is shown.

Referring to FIG. 3, the adjuster directly confirms that the test pattern for adjustment is projected on the screen S, and then determines the mis-convergence between the image patterns projected from the respective CRTs R, G, and B, and adjusts the adjustment direction. Determine and transmit the information to the microcomputer 10 by the remote controller, the microcomputer 10 stores the control point data for the corresponding point in the RAM inside the ASIC 20.

Subsequently, the ASIC 20 uses the data stored in the RAM of the EEPROM 30 and the internal RAM by the PLL 40 synchronized with the horizontal blanking signal H_BLK among the horizontal / vertical blanking signals H_BLK and V_BLK. Output the data according to the correction. The output data is converted into an analog signal through a digital-to-analog converter (D / A) and then applied to the convergence yoke (CY) and the deflection yoke through the sample / hold and filtering units (50, 60) and the amplifiers (AMP1, AMP2). It is applied to correct the miss convergence.

4 illustrates an internal configuration of the ASIC. When the microcomputer 10 accesses the convergence reference data stored in the EEPROM 30 and transmits the data to the ASIC 20, the adjustment is stored in the internal RAM 23. Through the point data, the horizontal / vertical correction unit 26 calculates correction data using the horizontal / vertical interpolation equation as follows.

The horizontal interpolation formula is

In addition, the vertical interpolation equation is as follows.

Subsequently, the convergence correction data is output to three channels of R, G, and B in synchronization with the horizontal / vertical blanking signal of the deflection unit, and the digital / analog converter (D / A) converts and outputs the correction correction data. In 60), the input analog data is separated into horizontal / vertical correction data, filtered after the noise, and output.

Thereafter, the data output from the sample / hold and filtering unit 60 is amplified by current so as to drive the convergence yoke CY and the horizontal / vertical convergence yoke CY of the corresponding CRTs R, G, and B for each color. Is applied to adjust the path of image projection.

Reference numeral 21, which is not described among the above-described operations, is an address generator for generating an address for accessing the RAM 23, and reference numeral 22 is an inspection pattern generator for generating an image signal according to a test pattern according to a control signal. Reference numeral 24 denotes an address controller for controlling the address generator 21. Reference numeral 25 denotes a test pattern control unit for controlling the test pattern generator 22 according to an address signal generated by the address control unit 24.

Therefore, the image on which the inspection pattern generated by the inspection pattern generator 22 is projected is reflected on the mirror M and then appears again on the screen S, whereby adjustment is made.

After the adjustment is completed without the mis-convergence part in the adjustment pattern, the microcomputer 10 reads the data of the adjustment point from the ROM 23 inside the ASIC 20, and then, in the EEPROM 30, each mode (for example, NTSC, PC, This saves the adjustment data for ED ...), which completes the adjustment for one mode.

At this time, the ASIC 20 should output the convergence data in real time, so it must output the convergence data at regular intervals (see FIG. 5).

After that, when a signal for correction is input from the user, the microcomputer reads the control point data for the mode and calculates it by software. The method performs a Lagrange calculation to obtain a correction value. Patent Nos. 95-3370 and 94-4398 previously filed by the applicant.

However, the conventional software processing method as described above has a very slow processing speed and cannot satisfy the desire of the viewer for quick viewing. In addition, in order to solve the excessive problem of time, which is a disadvantage of the software method, the operation is performed in hardware, but this causes a new problem of increased production cost and complicated system.

This is because operation logics for performing operations on the respective parameters according to the horizontal interpolation and the vertical interpolation are needed. Referring to FIG. 5, the adjustment point data is read from the EEPROM 30 and adjusted for each line. After calculating the point data, the parallel operation should be performed. After that, one vertical calculation unit is provided to calculate the horizontal interpolation data having the parallel operation on the vertical value and then obtain a correction value.

That is, the adjustment point data initially transmitted by the microcomputer 10 to the internal RAM 23 of the ASIC 20 are 35 (7 * 5) points indicated by X in FIG. 5. I am doing horizontal / vertical interpolation with these adjustment points. In the current scanline line of FIG. 5 shown The horizontal and vertical interpolation data of the point is as follows.

First, perform horizontal interpolation with the data of 7 points in (A) line, and then obtain the data of point ⓐ, and then use the data of 7 points in (B) line ⓑ and (C) line. From the line ⓒ, obtain the data of point ⓓ from line (d), and the ⓔ data from line (e). Finally, with these five points of data Get the data of the point. The same is true for data at other points.

Since the convergence data should be output from one scan line, 16 points indicated by ○ in FIG. 5 are attached, and six data at one point should be obtained for every 3.97 kHz (1 / 15.75Khz / 16). Since the data at one point is composed of six data such as RH, RV, GH, GV, BH and BV, one data must be obtained every 660ns (3.97㎲ / 6).

The time interval for outputting convergence data in NTSC is as follows.

Not only was it not easy to handle horizontal and vertical interpolation during this period, but even parallel processing for that hardware would add enormous amounts of hardware.

Therefore, the horizontal / vertical interpolation equation should be calculated within 660ns. To solve this problem, the hardware size of several horizontal / vertical interpolation blocks, which is a common design method, is so large (approximately 50,000 gates) that the hardware size is greatly increased. none.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and its object is to perform convergence correction mainly using a hardware method, but increase the processing speed, reduce the manufacturing cost, and simplify the configuration of the system. And providing the apparatus.

1 is an exemplary view showing the structure of a rear projection projection monitor

2 is an example of miss-convergence

3 is a flowchart according to a conventional miss-convergence correction

4 is a diagram illustrating a connection configuration between an internal ASIC configuration and a peripheral device of FIG. 3;

5 is an exemplary diagram for explaining convergence correction.

6 is a block diagram illustrating the connection between the ASIC internal configuration and peripheral devices related to convergence correction according to the present invention.

7 is an exemplary view for explaining the difference between the convergence correction according to the prior art and the present invention

The present invention for achieving the above object, in the convergence correction method for storing any reference interpolation data and correcting the convergence according to the request based on the stored reference interpolation data when the convergence request, A first process of storing horizontal convergence correction data; a second process of calculating horizontal convergence correction data for the current screen according to a correction request based on previously stored reference interpolation data when a correction request signal is input; and the second process Before the operation is completed, a third process of calculating the vertical convergence correction data based on the horizontal convergence correction data for the previous screen stored through the first process, and the operation is completed through the second process. Vertical convergence based on the horizontal convergence correction data for the current screen. And a fourth process of calculating the correction data.

According to a preferred embodiment of the present invention, after calculating the vertical convergence correction data in the third process or the fourth process, the method further includes displaying a screen corrected by the correction data.

According to another preferred embodiment of the present invention, the displaying of the screen may include: a first step of displaying the entire screen corrected according to the calculation of the vertical convergence correction data in the third process; After calculating the vertical convergence correction data in the process, a second step of displaying the entire screen corrected accordingly and a third step of selecting the second step when the first step and the second step occur simultaneously.

According to the present invention for achieving the above object, when the correction request signal is input, the microcomputer reads the adjustment point data from the EEPROM and transfers it to the convergence correction processing unit, and the convergence correction processing unit calculates convergence correction data for horizontal / vertical. In the convergence correction device, the convergence correction processing unit sequentially calculates each horizontal line based on the first storage unit for storing the adjustment point data read from the EEPROM and the horizontal adjustment point data stored in the first storage unit. A horizontal storage unit, a second storage unit for storing correction data of a previous image, a third storage unit for receiving and storing adjustment point data corrected by the horizontal correction unit, and a third storage unit Vertical compensator for calculating correction data for vertical adjustment point data based on the adjustment point data And a control unit configured to control the convergence correction data of the currently output screen output through the vertical correction unit until the calculation is completed in the horizontal correction unit based on the data stored in the second storage unit. To provide.

According to another preferred embodiment of the present invention, the first storage unit has a size of at least 210 bytes to store 35 adjustment points delivered by the microcomputer.

In addition, according to another preferred embodiment of the present invention, the third storage unit has a size of at least 480 bytes to store data of 80 points with horizontal interpolation from 35 adjustment points.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

First, referring to the technical concept applied in the present invention, the reason why it was difficult to process interpolation with conventional hardware was because it attempted to process both horizontal and vertical interpolation for a short time of 660 ns. In view of the fact that changes within / 16 seconds cannot be detected accurately, the previous screen and the current screen are not all converged and displayed, but one convergence is performed during the display time of 2 to 3 fields. It is to make it possible to increase satisfaction.

More specifically, with the data of 35 points transmitted from the microcomputer, only horizontal interpolation is processed while the current screen is displayed, and the convergence data during this period outputs data on the previous screen. And while the next screen is displayed with the horizontal interpolated data, the interpolated new data is output in real time.

Therefore, when the adjusted value on the current screen is transmitted to the microcomputer by the remote controller, the adjusted value to be changed is reflected on the next screen. If there is no adjusted value in the current screen, the adjusted value of the previous screen is the same as the adjusted value of the current screen, so the convergence data output is the same. In other words, the convergence interpolation value is delayed by one screen only when the adjustment value is changed in the current screen.

However, 60 screens are displayed per second and no matter how fast the coordinator adjusts, the screen cannot be identified several times. The maximum number of adjustments the controller can make in one second is about 10 times. The instantaneous delay at this time is 0.17 seconds. Therefore, the adjuster hardly feels the delay of the convergence output and feels immediately reflected on the screen as the adjustment is made.

As described above with reference to FIG. 6 to which a configuration in which the technical spirit of the present invention as described above is implemented in hardware is attached.

6 is a configuration diagram of a convergence correction apparatus according to the present invention, in which the EEPROM 30 storing the adjustment point data and the correction point data are read and stored in the first storage unit 110 when a correction request signal is input. For the microcomputer 10, the horizontal correction unit 120 for sequentially calculating each horizontal line based on the horizontal adjustment point data stored in the first storage unit 110, and the previous image (before the correction request signal) A second storage unit 300 that stores correction data, a third storage unit 130 that receives and stores adjustment point data corrected by the horizontal correction unit 120, and the third storage unit 130. The vertical correction unit 140 that calculates correction data for the vertical adjustment point data based on the adjustment point data stored in the control unit, and the convergence correction data of the currently output screen until the calculation is completed is stored in the second storage unit 300. To output data It consists of a control unit 200 that controls.

In this case, the first storage unit 110 is a RAM having control points of 35 points transmitted by the microcomputer 10 and is 210 bytes (35 * 6) in size.

In addition, the third storage unit 140 is a RAM having 80 points of data interpolated from 35 adjustment points and is 480 bytes (80 * 6) in size.

Looking at the operation of the convergence correction device according to the present invention configured as described above are as follows.

The microcomputer 10 reading the adjustment point data from the EEPROM 30 stores the data in the first storage unit 110. The horizontal correction unit 120 calculates horizontal correction data among the data stored in the first storage unit 110 and stores it in the third storage unit 130. During this operation time, the second storage unit 300 outputs previously stored correction data.

When the above process is completed, the horizontal correction data of the third storage unit 130 is moved to the second storage unit 300 and the vertical correction unit 140.

In this case, when there is no signal input from the third storage unit 130, the vertical correction unit 140 calculates data for vertical convergence correction based on the horizontal correction data output from the second storage unit 300. Output all correction data.

In the above-described process, operations of the vertical correction unit 140 and the second storage unit 300 are performed by the control unit 200.

In the above-described configuration and operation according to the present invention, reference numeral 100, which is not described, indicates an ASIC according to the present invention.

Then, when the design of the horizontal / vertical interpolation formula as in the present invention, let's see how easy the hardware design of the horizontal / vertical interpolation formula.

First, the horizontal interpolation step is as follows.

In the accompanying drawings, FIG. 7 shows 35 points of adjustment points that the microcomputer 10 delivers inside the ASIC 100 according to the present invention, and FIG. 8 shows a point where horizontal interpolation should be performed from these data.

That is, the points represented by the original characters 1 to 16 are distributed in five lines at which adjustment points are located, as shown by reference numeral A for the entire image.

Therefore, during 1/60 second when one field is displayed, the horizontal interpolation data of 45 points except 35 points of FIG. 7 among 80 points should be obtained. The time allocated to one point is 370 s (1/60 / 45) and the time allotted to obtain a single data is 62㎲ (370㎲ / 6), which is enough for horizontal interpolation.

This is because, in a converged system, the main clock is at least 4Khz. Therefore, at least 250 main clocks are allocated during 62ms.

In addition, the vertical interpolation step is as follows.

Vertical interpolation is performed with 80 points of horizontal interpolation data. As described above, one data must be obtained within 660ns (1 / 15.75Khz / 16/6) for NTSC. At least 2.5 MAIN CLOCKs are allocated for 660 ns. In fact, there is no difficulty in performing vertical interpolation during this period, and the delay in the vertical interpolation block does not exceed this period.

By providing the convergence correction method and apparatus according to the present invention operating as described above, it is possible to perform the convergence correction mainly using a hardware method, but increase the processing speed, reduce the manufacturing cost and simply implement the system configuration.

Claims (6)

A convergence correction method for storing arbitrary reference interpolation data and correcting convergence according to a request based on stored reference interpolation data when a convergence request is provided. A first step of storing horizontal convergence correction data for the previous screen; A second process of calculating horizontal convergence correction data for the current screen according to the correction request based on the pre-stored reference interpolation data when the correction request signal is input; A third process of calculating vertical convergence correction data on the basis of horizontal convergence correction data for the previous screen stored in the first process before the operation is completed through the second process; And And a fourth process of calculating the vertical convergence correction data based on the horizontal convergence correction data for the current screen when the calculation is completed through the second process. The method of claim 1, And after calculating the vertical convergence correction data in the third process or the fourth process, displaying the screen corrected by the correction data. The method of claim 2, The displaying of the screen may include: a first step of calculating the vertical convergence correction data in the third process and then displaying the entire screen corrected accordingly; A second step of displaying the entire screen corrected according to calculating the vertical convergence correction data in the fourth process; And And a third step of selecting the second step when the first step and the second step occur at the same time. In the convergence correction device for inputting the correction request signal, the microcomputer reads the adjustment point data from the EEPROM to the convergence correction processing unit, and the convergence correction processing unit calculates the convergence correction data for horizontal / vertical, The convergence correction processing unit includes a first storage unit storing adjustment point data read from the EEPROM; A horizontal correction unit configured to sequentially calculate each horizontal line based on the horizontal adjustment point data stored in the first storage unit; A second storage unit which stores correction data for the previous image; A third storage unit for receiving and storing adjustment point data corrected by the horizontal correction unit; A vertical corrector configured to calculate correction data for the vertical adjustment point data based on the adjustment point data stored in the third storage unit; And The convergence correction data of the currently output screen output through the vertical correction unit until the operation is completed in the horizontal correction unit comprises a control unit for controlling to output based on the data stored in the second storage unit Correction device. The method of claim 4, wherein And the first storage unit has a size of at least 210 bytes to store 35 adjustment points transmitted by the microcomputer. The method of claim 4, wherein And the third storage unit has a size of at least 480 bytes to store data of 80 points horizontally interpolated from 35 adjustment points.