JP3201099B2 - Digital convergence device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital convergence apparatus for correcting convergence of a color television receiver.

[0002]

2. Description of the Related Art In general, in a projection type color receiver for enlarging and projecting on a screen using three projection tubes emitting three primary colors, the angle of incidence of the projection tube on the screen is different for each projection tube. As a result, color shift occurs on the screen. The superposition of these three primary colors, so-called convergence, employs a method of creating a convergence correction waveform in an analog manner in synchronization with the horizontal and vertical scanning periods, and adjusting the waveform by changing the size and shape of the waveform. There is a problem with accuracy. Therefore, as a method capable of responding to various signals and having high convergence accuracy, for example, Japanese Patent Application Laid-Open
A digital convergence device is disclosed in Japanese Patent Application Laid-Open No. 130288/130.

The conventional digital convergence device will be described below. FIG. 7 shows a block diagram of a conventional digital convergence device. This involves projecting a convergence correction pattern such as a crosshatch pattern (shown in FIG. 8) on the screen, digitally writing convergence correction amount data for each adjustment point into a frame memory, and reading out this data. / A conversion and performs convergence correction.

In FIG. 7, 1 is a read address control unit, 2 is a cross hatch generator, 3 is a video circuit, 4 is a write address control unit, 5 is a control panel, 6 is a reversible counter, 7 is a multiplexer, and 8 is 1 A frame memory, 9 a register, 10 a processing unit between vertical adjustment points, 1
1 is a D / A conversion circuit, 12 is an LPF, 13 is a scanning line number detecting section, 14 is an adjustment point number setting section, 15 is a coefficient calculating section,
6 is an output amplifying unit, and 17 is a deflection circuit.

A horizontal / vertical period pulse synchronized with the deflection current period is applied as a synchronization signal to a synchronization signal input terminal 20 to drive the read address control unit 1. The cross hatch generator 2 is driven by using the pulse from the read address control unit 1, and the video circuit 3 projects a cross hatch pattern on a projection screen. On the other hand, a cross point (for example, A in FIG. 7) of a position requiring convergence correction is designated by an address key of the control panel 5, and a position address is set in the write address control unit 4. Next, the correction amount is written to the one-frame memory 8 through the data reversible counter 6 while looking at the screen, using a data write key for a color to be corrected, for example, a red data provided on the control panel 5. Normally this one-frame memory 8
Switching is controlled by the multiplexer 7 so that writing to the memory is performed during the blanking period of the video signal.
Therefore, the reading is not impaired.

[0006] In this manner, the same operation is performed at each adjustment point. Next, reading of the one-frame memory 8 is performed for each adjustment point position on the screen by the read address control unit 4, and is performed through the register 9 driven by the read address control unit 1 to perform processing between vertical adjustment points. The section 10 performs correction amount processing in the vertical scanning direction between adjustment points. In order to support various signal sources,
It is necessary to perform processing between adjustment points according to the number of scanning lines.
Therefore, the input synchronization signal is supplied to the number-of-scanning-lines detecting unit 13 to detect the number of scanning lines in one field, and is applied to the number-of-adjustment-points setting unit 14. The number-of-adjustment-points setting unit 14 determines the number of scanning lines M in one field and the number L of adjustment points in the vertical direction from
Calculates the number N of scanning lines between the M / (L + 1) adjustment points,
It is added to the coefficient calculator 15. In addition to the write address control unit 4 and the read address control unit 1, the operation is switched to every N lines.

[0007] The output of the vertical adjustment point processing section 10 operating as described above is input to the D / A conversion circuit 11, where a signal converted into an analog quantity is obtained. The signal between the horizontal adjustment points is supplied to a convergence yoke 18 after the correction amount of the adjustment point in each row is smoothed by a low-pass filter (LPF) 12, amplified by an output amplifier 16, and then sent to a convergence yoke 18. A detection signal from the scanning line number detection unit 13 is applied to the deflection circuit 17 as a system switching signal, and switches the deflection amplitude, frequency, and the like. As described above, since independent correction can be performed for each signal point for each adjustment point, convergence correction can be performed with high accuracy.

[0008]

However, in the above-described conventional configuration, the convergence adjustment can be accurately performed for each signal source. However, the display of the adjustment point outside the screen in the conventional overscan image is performed. Interpolation 2
The extrapolation point interpolation was performed based on the data of the adjustment point of the interpolation as the blinking display of the point and the correction of the extrapolation point, but the extrapolation point is displayed on the screen when the underscan image is input at this time. When displayed on the screen, there is a problem in that the cursor does not go to the extrapolation point, blinks at two interpolation points, cannot be adjusted independently, and adjustment is difficult.

[0009]

In order to solve the above-mentioned problems, a digital convergence apparatus according to the present invention generates a plurality of convergence adjustment points in a horizontal and vertical direction on a screen of a color television receiver to display a cursor. Means for inputting correction data for each adjustment point in the screen, means for obtaining the correction data for each adjustment point outside the screen by extrapolation from the correction data in the screen, and a cursor for each adjustment point outside the screen. Means for displaying the display at adjustment points in the screen determined by extrapolation operation, means for digitally storing the convergence correction amount of each adjustment point, and synchronization in which the correction data from the storage means is input to the receiver. Means for reading in synchronization with a signal, means for amplifying the read-out correction data and supplying it to the correction coil, together with correction data for a memory as the storage means ON means the surface is preset or underscan / overscan, the result of detection of said preset data, extrapolation arithmetic /
It is provided with means for turning off.

Further, the digital convergence apparatus of the present invention comprises a means for generating a plurality of convergence adjustment points in a horizontal and vertical direction on a screen of a color television receiver and displaying the cursor, and a correction of each adjustment point in the screen. A means for inputting data and calculating the correction data of each adjustment point outside the screen by extrapolation calculation from the correction data within the screen, and adjusting the cursor display of each adjustment point outside the screen by the extrapolation calculation Means for digitally storing the convergence correction amount of each adjustment point; means for reading out the correction data from the storage means in synchronization with a synchronization signal input to the receiver; and Means for amplifying the corrected data and supplying it to the correction coil, means for discriminating overscan / underscan by detecting the amplitude of the deflection, and The result of out, those having means for ON / OFF the extrapolation computation.

The digital convergence apparatus of the present invention further comprises means for generating a plurality of convergence adjustment points in the horizontal and vertical directions on the screen of the color television receiver and displaying the cursor, and correcting each of the adjustment points in the screen. A means for inputting data and calculating the correction data of each adjustment point outside the screen by extrapolation calculation from the correction data within the screen, and adjusting the cursor display of each adjustment point outside the screen by the extrapolation calculation Means for digitally storing the convergence correction amount of each adjustment point; means for reading out the correction data from the storage means in synchronization with a synchronization signal input to the receiver; and Means for amplifying the corrected data and supplying it to the correction coil, and means for turning on / off the extrapolation operation by detecting the frequency of the input signal. It is.

[0012]

According to the first and second aspects of the invention, even if the input signal changes between underscan and overscan, ON / OFF of the extrapolation operation can be preset in accordance with the input signal, so that digital convergence correction can be performed. Since the adjustment can be performed optimally, high-precision adjustment can be easily performed.

According to the third aspect of the present invention, even if the input signal changes to underscan / overscan, the screen amplitude is automatically detected and the extrapolation operation is automatically turned on / off according to the input signal. Since the adjustment of the digital convergence correction can be optimally performed, the adjustment can be easily performed with high accuracy.

According to the present invention, even if the input signal changes from underscan / overscan, the frequency of the input signal is detected, and the extrapolation operation is automatically turned on / off according to the input signal. Since the adjustment of the digital convergence correction can be optimally performed, the adjustment can be easily performed with high accuracy.

[0015]

(Embodiment 1) A first embodiment of the present invention will be described below with reference to the drawings.

FIGS. 1, 2, 3 and 4 are block diagrams of a digital convergence device according to a first embodiment of the present invention, a block diagram of an over / under scan discriminating circuit of a main part thereof, FIG. 3 shows a relationship diagram between a screen, a cross hatch and an extrapolation point, and a relationship diagram between two extrapolation points of extrapolation operation data. In FIG. 1, 21, 22
Is a multiplexer for turning on / off the extrapolation operation, 23 is an extrapolation point operation unit for automatically obtaining extrapolation point data from two interpolation data, 24 is an over / under scan discrimination circuit, and 25 is a vertical direction And a vertical operation circuit 26 for performing an operation between the adjustment points, and an address control unit 26 for controlling reading and writing of the memory. In FIG. 2, reference numeral 26 denotes a nonvolatile memory for storing ON / OFF of the extrapolation point calculation, 27 denotes a memory reading circuit for reading the memory for each input signal, and 28 turns on extrapolation point interpolation based on the read data. An extrapolation operation switching circuit that outputs a signal for switching between / OFF. In FIG. 3, 29 is a cross hatch, 30 is a screen frame, and 31 is an adjustment point.
Components that operate in the same manner as in FIG. 7 of the conventional embodiment are denoted by the same reference numerals, and description thereof is omitted.

The operation of the digital convergence device according to the present embodiment having the above-described configuration will be described below. A synchronizing signal is input to the input terminal 20, and various address signals for controlling the one-frame memory 8 are generated by the address control unit 26. For example, the crosshatch generator 2 generates, as shown in the display screen diagram of FIG. The horizontal and vertical cross hatch patterns 29 are generated and projected on the screen by the video circuit 3. Next, an adjustment point of a place to be corrected and a corrected color are selected by a cursor (not shown) of the control panel 5 and stored in an area of the one-frame memory 8 corresponding to the address. Here, when the extrapolated point is outside the screen as in (a of adjustment point 32) as in (a) of FIG. 3, the over / under scan discriminating circuit 24 determines that it is overscan, and the operation from the control panel is performed. Multiplexers 21 and 2 pass through extrapolation point arithmetic circuit 23
2 is controlled. Therefore, the adjustment point outside the screen (extrapolation point) is determined by the correction data of the adjustment point (display screens b and c) in the screen of FIG. Is obtained, for example, by linear approximation from the correction data in the above.

As shown in FIG. 3B, the extrapolation point is (adjustment point 3).
In the case of being within the screen as in a) of 2), the over / under scan discrimination circuit 24 discriminates an underscan, and controls the multiplexers 21 and 22 so that the operation from the control panel does not pass through the extrapolation point calculation circuit 23. I do. Therefore, the extrapolated points can be adjusted independently of the correction data of the adjustment points (display screens b and c) in the screen of FIG. 3 (b). One frame in which the data adjusted in this way is written
Since only the correction data at the location corresponding to each adjustment point is stored in the memory 10, the vertical operation circuit 25 interpolates between the vertical adjustment points to correspond to each scanning line between the adjustment points. Correction data is being created. Vertical operation unit 2
5 is converted into an analog quantity by a D / A conversion circuit 11 and smoothed in a horizontal direction by an LPF 12 to generate a correction waveform.

The operation of the over / under scan discriminating circuit will now be described. When the input signal is optimally projected on the screen and the cross hatch signal 30 is output, a) and b) in FIG.
Control panel 5 as to whether or not extrapolation points are on the screen
Is operated, the ON / OFF data of the extrapolation point calculation is written into the nonvolatile memory 27, and the memory reading circuit 2
8, the data is read out, and the extrapolation point switching circuit 29 turns ON / OFF the extrapolation point calculation. Further, since ON / OFF of the extrapolation point interpolation is stored in the nonvolatile memory, it is automatically switched for each input signal.

Next, FIG. 4 is used to explain the extrapolation operation means in detail. As for the extrapolation point a, the extrapolation point calculation circuit 23 obtains the correction data D3 by linear approximation from the correction data D1 at the point c of the adjustment point in the screen and the correction data D2 at the point b.
At this time, the cursor is displayed not at the position of the extrapolation point a but at two adjustment points b and c in the screen, which are basic data of the extrapolation operation, to perform the extrapolation operation display. In detecting the extrapolation point, the control signal from the control panel 5 is supplied to an extrapolation point calculation circuit 23 to determine whether the signal is within the screen or outside the screen. This determination signal is supplied to the cross hatch generator 2. The extrapolation point of the cursor is displayed. Therefore, for example, as shown in the display screen diagram of FIG.
Is displayed, and at the adjustment point d in the screen, a square cursor is displayed only at the d position. That is, the cursor is 1
When only two cursors are displayed, it is the position of the adjustment point in the screen, and when two cursors are displayed, it indicates the position of the adjustment point (extrapolation point) outside the screen.

As described above, according to this embodiment, the ON / OFF of the extrapolation point calculation is preset for each input signal, so that the deflection amplitude of the receiver is overscanned and the adjustment point outside the screen is not displayed. In such a case, the extrapolation point display shows cursors at two adjustment positions in the screen, adjustment outside the screen can be automatically performed by extrapolation calculation, and when the deflection amplitude of the receiver is an underscanned image, The operation of extrapolation points and the display of extrapolation points can be prohibited.
Even when the extrapolation point is inside or outside the screen in an underscanned image or the like, the optimal convergence adjustment can be performed in an optimal state according to the input signal.

(Embodiment 2) Hereinafter, a second embodiment of the present invention will be described with reference to the drawings.

FIG. 5 is a block diagram showing a digital convergence apparatus according to a second embodiment of the present invention. In FIG. 5, the difference from the first embodiment is that the over / under scan is determined by the deflection amplitude. In FIG. 5, 33
Is a deflection amplitude control circuit, 34 is a reference voltage for deflection amplitude control when the extrapolation point is in the screen frame, 35 and 36 are comparators, 37 is a horizontal extrapolation point ON / OFF signal, and 38 is a vertical extrapolation point. Extrapolation point ON / OFF signal. In FIG. 5, components that operate in the same manner as FIG. 1 and FIG. 7 of the conventional embodiment are denoted by the same reference numerals, and description thereof is omitted.

The operation of the digital convergence device of this embodiment having the above-described configuration will be described below. Here, the operation of switching the extrapolation point calculation between the control panel 5 and the frame memory 8 is the same as that of the first embodiment, and thus the description is omitted. When a signal is input to the receiver and the amplitude in the horizontal direction is controlled by the deflection amplitude control circuit 33 to control the deflection circuit 17, the negative voltage of the comparator 35 is varied. Is applied to the + side of the comparator, it is possible to determine whether the extrapolated point is inside or outside the screen based on whether the output voltage from the comparator 35 is + or-. According to the determination signal 37, the extrapolation operation in the horizontal direction is
N / OFF. Similarly, in the vertical direction, the extrapolation operation in the vertical direction is turned on / off by the output of the comparator 36. As described above, by comparing the screen amplitude of each input signal with the reference amplitude, over / under scanning can be determined, and the extrapolation operation can be turned ON / OFF.

Embodiment 3 Hereinafter, a third embodiment of the present invention will be described with reference to the drawings.

FIG. 6 is a block diagram showing a digital convergence device according to a second embodiment of the present invention. In FIG. 6, the difference from the first embodiment is that over / under scan is determined by the frequency of the input signal. In FIG. 6, reference numeral 39 denotes a horizontal synchronizing signal, 40 denotes a vertical synchronizing signal, 41 denotes a reference clock generator, 42 denotes a counter for counting the horizontal frequency, 43 denotes a minute period for lowering the frequency of the reference clock, and 44 denotes a vertical frequency. Counter 4
5 is a horizontal frequency discriminating circuit, 46 is a vertical discriminating circuit, and 47 is an input signal discriminating circuit for discriminating an input signal based on the horizontal and vertical frequencies. In FIG. 6, components that operate in the same manner as FIG. 1 and FIG. 7 of the conventional embodiment are denoted by the same reference numerals, and description thereof is omitted.

The operation of the digital convergence device of the present embodiment having the above-described configuration will be described below. Here, the operation of switching the extrapolation point calculation between the control panel 5 and the frame memory 8 is the same as that of the first embodiment, and thus the description is omitted. When a signal is input to the receiver, the horizontal synchronizing signal 39 is counted by the counter 42 based on the reference clock input from the reference clock generator 41. The horizontal frequency determination circuit 45 determines the frequency of the horizontal synchronization signal based on the counted data. Also, the vertical synchronization signal 4
Similarly, 0 is counted by the counter 44 by the clock whose frequency is reduced by the dividing period 43 from the reference clock input from the reference clock generator 41. The frequency of the vertical synchronization signal is determined by the vertical frequency determination circuit 45 based on the counted data. Based on the horizontal / vertical frequency data, the input signal determination circuit 47 determines over / under scan and outputs an extrapolation operation ON / OFF signal.
Turn on / off extrapolation automatically.

In the first, second and third embodiments, the projection type color receiver has been described for easy understanding. However, the present invention is also effective for a shadow mask type direct-view type receiver. Needless to say.

[0029]

As described above, according to the present invention,
By turning ON / OFF the extrapolation operation by over / under scanning of the input signal, the optimal digital convergence can be adjusted in accordance with the input signal, so that highly accurate correction can be easily realized in a short time.

Further, by presetting ON / OFF of the extrapolation operation for each input signal, it is possible to perform an optimal digital convergence adjustment according to the input signal, such as at the time of readjustment.
High-precision correction can be easily realized in a short time.

As described above, according to the present invention, the optimum digital convergence can be adjusted according to the input signal by automatically determining ON / OFF of the extrapolation operation by judging the screen amplitude. High-precision correction can be easily realized in time.

Further, according to the present invention, an over / under scan is determined by performing an input signal determination circuit based on the horizontal frequency and the vertical frequency, and the extrapolation operation ON / OFF is automatically performed.
By automatically performing the OFF signal, the optimal digital convergence can be adjusted according to the input signal, and highly accurate correction can be easily realized in a short time.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a digital convergence device according to a first embodiment of the present invention.

FIG. 2 is a block diagram of an overs / under scan discrimination circuit in the digital convergence device.

FIGS. 3A and 3B are diagrams showing display screens for explaining the operation of the embodiment. FIGS.

FIG. 4 is a diagram for explaining the operation of the embodiment.

FIG. 5 is a block diagram showing a configuration of a digital convergence device according to a second embodiment of the present invention.

FIG. 6 is a block diagram showing a configuration of a digital convergence device according to a third embodiment of the present invention.

FIG. 7 is a block diagram of a conventional digital convergence device.

FIG. 8 is a diagram showing a display screen for explaining the operation of a conventional digital convergence device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 read address control unit 2 cross hatch generator 3 video circuit 4 write address control unit 5 control panel 6 reversible counter 7 multiplexer 8 1 frame memory 9 register 10 vertical adjustment point processing unit 11 D / A conversion circuit 12 LPF 13 scanning Line number detection unit 14 Adjustment point number setting unit 15 Coefficient operation unit 16 Output amplification unit 17 Deflection circuit 18 Convergence coil 19 Deflection coil 21, 22 Multiplexer 23 Extrapolation point operation circuit 24 Overscan / underscan discrimination circuit 25 Vertical operation circuit 26 Address Generation Unit 27 Non-Volatile Memory 28 Memory Readout Circuit 29 Extrapolation Operation Switching Circuit 30 Cross Hatch 31 Screen Frame 32 Adjustment Point 33 Deflection Amplitude Control Circuit 34 Reference Voltage Generator 35, 36 Comparator 41 Reference Clock Generator 42, 44 counter 43 minute period 45 horizontal frequency discriminating circuit 46 vertical frequency discriminating circuit 47 input signal discriminating circuit

Continuation of the front page (56) References JP-A-60-130288 (JP, A) JP-A-3-117088 (JP, A) JP-A-60-185482 (JP, A) JP-A-5-7367 (JP) JP-A-5-227536 (JP, A) JP-A-60-33791 (JP, A) JP-A-58-153479 (JP, A) JP-A-62-11388 (JP, A) 5-252543 (JP, A) JP-A-7-67119 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04N 9/28

Claims (4)

(57) [Claims] 1. A means for generating a plurality of convergence adjustment points in a horizontal and vertical direction on a screen of a color television receiver and displaying a cursor, inputting correction data of each adjustment point in the screen, Means for obtaining the correction data of each adjustment point by extrapolation from the correction data in the screen, means for displaying the cursor display of each adjustment point outside the screen at the adjustment point in the screen obtained by the extrapolation calculation, and each adjustment point Means for digitally storing the amount of convergence correction, means for reading correction data from the storage means in synchronization with a synchronization signal input to the receiver, and amplifying and correcting the read correction data. Means for supplying the image data to the coil for detection, detecting means for detecting whether the screen is underscan / overscan, and turning on / off the extrapolation interpolation operation based on the detection result.
A digital convergence device comprising: means for turning off. 2. The digital apparatus according to claim 1, wherein the means for detecting whether the screen is underscan / overscan detects preset data stored together with correction data in a memory serving as the storage means. Convergence device. 3. A means for generating a plurality of convergence adjustment points in the horizontal and vertical directions on a screen of a color television receiver and displaying a cursor, and inputting correction data of each adjustment point in the screen, and outputting the correction data to the outside of the screen. Means for obtaining the correction data of each adjustment point by extrapolation from the correction data in the screen, means for displaying the cursor display of each adjustment point outside the screen at the adjustment point in the screen obtained by the extrapolation calculation, and each adjustment point Means for digitally storing the amount of convergence correction, means for reading correction data from the storage means in synchronization with a synchronization signal input to the receiver, and amplifying and correcting the read correction data. Means for supplying to the coil for detection, detecting means for detecting whether the screen is underscan / overscan based on the amplitude of the deflection, and ON / OFF of the extrapolation operation based on the detection result. And a digital convergence device. 4. A means for generating a plurality of convergence adjustment points in a horizontal and vertical direction on a screen of a color television receiver and displaying a cursor, and inputting correction data of each adjustment point in the screen, and outputting the correction data to the outside of the screen. Means for obtaining the correction data of each adjustment point by extrapolation from the correction data in the screen, means for displaying the cursor display of each adjustment point outside the screen at the adjustment point in the screen obtained by the extrapolation calculation, and each adjustment point Means for digitally storing the amount of convergence correction, means for reading correction data from the storage means in synchronization with a synchronization signal input to the receiver, and amplifying and correcting the read correction data. Means for supplying a signal to the input coil, detection means for detecting whether the screen is underscan / overscan at the horizontal / vertical frequency of the input signal, and extrapolation calculation based on the detection result. A digital convergence device comprising: means for turning on / off.