JPH07107499A - Digital convergence device - Google Patents

Abstract

PURPOSE:To make an optimal adjustment according to an input signal and to easily realize the highly accurate correction in a short time by turning on and off an extrapolating arithmetic operation by over and under scanning of the input signal. CONSTITUTION:A synchronizing signal is inputted to an input terminal 20. Various address signals to control a memory 8 are generated by an address control part 26. A cross hatch generation part 2 generates a cross hatch pattern in the horizontal and the vertical directions to be reflected on the screen of a video circuit 3. Then, the adjustment point in the place to be corrected and the color are selected with the use of a cursor key of a control panel 5 and are stored in the area of the memory 8 corresponding to the address. When an extrapolation point is outside the chart, a discrimination circuit 24 discriminates it as over scanning and the control panel controls multiplexers 21 and 22 to pass an arithmetic circuit 23. When the extrapolate point is inside the screen, the circuit 24 discriminates it as under scanning and the control panel controls multiplexers 21 and 22 not to pass the circuit 23.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art Generally, in a projection type color image receiving apparatus for enlarging and projecting in a screen by using three projection tubes which emit three primary colors, the incident angles of the projection tubes with respect to the screen are different in each projection tube. Therefore, color shift occurs on the screen. Superimposition of these three primary colors, so-called convergence, is a method in which a convergence correction waveform is created in an analog manner in synchronization with the horizontal and vertical scanning periods, and the size and shape of this waveform are changed to make adjustments. There is a problem in terms of accuracy. Therefore, as a method capable of supporting various signals and having high convergence accuracy, for example, Japanese Patent Laid-Open No.
A digital convergence device disclosed in Japanese Patent Laid-Open No. 130288 has been proposed.

The conventional digital convergence device will be described below. FIG. 7 shows a block diagram of a conventional digital convergence device. This displays a convergence correction pattern such as a crosshatch pattern (shown in FIG. 8) on the screen, digitally writes the convergence correction amount data for each adjustment point to the frame memory, and reads this data D A / A conversion is performed to perform convergence correction.

In FIG. 7, 1 is a read address control unit, 2 is a crosshatch 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. Frame memory, 9 is a register, 10 is 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 detection unit, 14 is an adjustment point number setting unit, 15 is a coefficient calculation unit, 1
Reference numeral 6 is an output amplifier, and 17 is a deflection circuit.

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

In this way, the same operation is performed at each adjustment point. Next, the reading of the 1-frame memory 8 is performed by the read address control unit 4 for each adjustment point position on the screen, and through the register 9 driven by the read address control unit 1, the vertical adjustment point processing is performed. The correction amount process in the vertical scanning direction between the adjustment points is performed in the unit 10. In order to correspond to various signal sources,
It is necessary to perform processing between adjustment points according to the number of scanning lines.
Therefore, the input synchronizing signal is supplied to the scanning line number detection unit 13, detects the number of scanning lines in one field, and is applied to the adjustment point number setting unit 14. In the number-of-adjustment-points setting unit 14, the number of scanning lines in one field is M
Is the number of scanning lines N between 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 every N lines.

The output of the vertical adjustment point-to-point processing unit 10 which operates as described above is input to the D / A conversion circuit 11, where a signal converted into an analog amount is obtained. The signal between the adjustment points in the horizontal direction is smoothed by the low-pass filter (LPF) 12 for the correction amount at the adjustment points in each row, amplified by the output amplification section 16, and then supplied to the convergence yoke 18. Further, the detection signal from the scanning line number detection unit 13 is applied to the deflection circuit 17 as a system switching signal to switch the deflection amplitude and frequency. In this way, since correction can be independently performed for each adjustment point for each signal source, it is possible to accurately perform convergence correction.

[0008]

However, in the above-mentioned conventional configuration, although the convergence adjustment can be accurately adjusted for each signal source, the adjustment points outside the screen are displayed in the conventional overscan image. As interpolation 2
The points were blinked and extrapolation points were interpolated by the data of the adjustment points of the extrapolation to correct the extrapolation points.However, if an underscan image was input at this time, the extrapolation points are displayed on the screen. When it is displayed on the screen, the cursor does not go to the extrapolation point, the two interpolation points are displayed in blinking, and the adjustment cannot be performed independently, which makes the adjustment difficult.

[0009]

In order to solve the above-mentioned problems, the digital convergence apparatus of the present invention generates a plurality of convergence adjustment points in the horizontal and vertical directions on the screen of a color television receiver to display a cursor. Means for inputting the correction data of each adjustment point on the screen, the correction data for each adjustment point outside the screen is obtained by extrapolation from the correction data for the screen, and the cursor for each adjustment point outside the screen. Means for displaying a display at adjustment points on the screen obtained by extrapolation calculation, means for digitally storing the convergence correction amount at each adjustment point, and synchronization for inputting correction data from the storage means to the receiver. Together with a means for reading in synchronization with a signal, a means for amplifying the read correction data and supplying it to a correction coil, and a correction data in 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 a means for turning it off.

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 a color television receiver and displaying the cursor, and correcting each adjustment point in the screen. By inputting data, the correction data for each adjustment point outside the screen can be calculated by extrapolation from the correction data inside the screen, and the cursor display for each adjustment point outside the screen can be calculated by extrapolation. Means for digitally storing the convergence correction amount at each adjustment point, means for reading the correction data from the storage means in synchronization with a synchronization signal input to the receiver, and means for reading the correction data. Means for amplifying the corrected data and supplying it to the correction coil; and means for determining overscan / underscan by detecting the amplitude of deflection. The result of out, those having means for ON / OFF the extrapolation computation.

Further, the digital convergence apparatus of the present invention 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 adjustment point in the screen. By inputting data, the correction data for each adjustment point outside the screen can be calculated by extrapolation from the correction data inside the screen, and the cursor display for each adjustment point outside the screen can be calculated by extrapolation. Means for digitally storing the convergence correction amount at each adjustment point, means for reading the correction data from the storage means in synchronization with a synchronization signal input to the receiver, and means for reading the correction data. A means for amplifying the corrected data to be supplied to the correction coil and a means for turning on / off the extrapolation interpolation operation by detecting the frequency of the input signal are also provided. It is.

[0012]

According to the first and second aspects of the present invention, even if the input signal changes between underscan and overscan, ON / OFF of the extrapolation calculation can be preset according to the input signal. Since the adjustment can be performed optimally, it becomes possible to easily perform high-precision adjustment.

According to the third aspect of the present invention, even if the input signal changes between underscan and overscan, the screen amplitude is automatically detected and the extrapolation calculation is automatically turned ON / OFF according to the input signal. Therefore, the digital convergence correction can be optimally adjusted, so that the highly accurate adjustment can be easily performed.

According to the fourth aspect of the present invention, even if the input signal changes between underscan and overscan, the frequency of the input signal is detected and the extrapolation calculation is automatically turned ON / OFF according to the input signal. Therefore, the digital convergence correction can be optimally adjusted, so that the highly accurate adjustment can be easily performed.

[0015]

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

1, FIG. 2, FIG. 3, and FIG. 4 are block diagrams of a digital convergence apparatus according to the first embodiment of the present invention, a block diagram of an over / under-scan determination circuit of its main part, and over / under scanning. The figure of a relation with a screen, a crosshatch, and an extrapolation point, and the figure of relation with two interpolation points of extrapolation calculation data are shown. In FIG. 1, 21, 22
Is a multiplexer for turning on / off the extrapolation operation, 23 is an extrapolation point calculation unit that automatically obtains extrapolation point data from the data of two interpolating points, 24 is an over / underscan determination circuit, and 25 is a vertical direction A vertical operation circuit 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 is a non-volatile memory for storing ON / OFF of extrapolation point calculation, 27 is a memory reading circuit for reading the memory for each input signal, and 28 is extrapolation point interpolation ON according to the read data. The extrapolation calculation switching circuit outputs a signal for switching between ON and OFF. Further, in FIG. 3, 29 is a cross hatch, 30 is a screen frame, and 31 is an adjustment point.
It should be noted that components operating in the same manner as in the conventional embodiment shown in FIG.

The operation of the thus constructed digital convergence apparatus of this embodiment will be described below. A synchronizing signal is input to the input terminal 20, an address control unit 26 generates various address signals for controlling the 1-frame memory 8, and the crosshatch generator 2 outputs, for example, as shown in the display screen diagram of FIG. The horizontal and vertical cross hatch patterns 29 are generated and displayed on the screen by the video circuit 3. Next, an adjustment point at a location to be corrected and a color to be corrected are selected by a cursor key (not shown) of the control panel 5, and the selected color is stored in the area of the 1-frame memory 8 corresponding to the address. Here, when the extrapolation point is outside the screen as shown in (a) of FIG. 3A (adjustment point 32a), the over / underscan determination circuit 24 determines overscan, and the operation from the control panel is performed. The multiplexers 21 and 2 are arranged so as to pass through the extrapolation point calculation circuit 23.
Control 2 Therefore, the adjustment points outside the screen (extrapolation points) are based on the correction data of the adjustment points (display screens b and c) in the screen of FIG. For example, it can be obtained by linear approximation from the correction data inside.

Further, as shown in FIG. 3B, the extrapolation point is (adjustment point 3
2), if it is in the screen, the over / underscan discrimination circuit 24 discriminates the underscan, and controls the multiplexers 21 and 22 so that the operation from the control panel does not pass through the extrapolation point arithmetic circuit 23. To do. Therefore, the extrapolation points can be independently adjusted regardless of the correction data of the adjustment points (display screens b and c) in the screen of FIG. 3b). One frame in which the data adjusted in this way is written
Since the memory 10 stores only the correction data at the locations corresponding to the respective adjustment points, the vertical arithmetic circuit 25 interpolates between the adjustment points in the vertical direction to correspond to each scanning line between the adjustment points. We are creating correction data. Vertical calculation unit 2
The output from 5 is converted into an analog amount by the D / A conversion circuit 11 and is horizontally smoothed by the LPF 12 to create a corrected waveform.

The operation of the over / underscan discrimination circuit will be described below. When an input signal is optimally displayed on the screen and a crosshatch signal 30 is output, a) and b) in FIG.
Control panel 5 without extrapolation points on the screen
Is operated, ON / OFF data for extrapolation point calculation is written in the nonvolatile memory 27, and the memory reading circuit 2
The data is read out by 8, and the extrapolation point switching circuit 29 turns on / off the extrapolation point calculation. Since ON / OFF of the extrapolation point interpolation is stored in the non-volatile memory, it automatically switches for each input signal.

Next, FIG. 4 is used to explain the extrapolation calculation means in detail. 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 and the correction data D2 at the point b in the screen.
At this time, the cursor is displayed not at the position of the extrapolation point a but at the two points of the adjustment points b and c on the screen, which are the basic data of the extrapolation calculation, and the extrapolation calculation is displayed. For the detection of the extrapolation point, the control signal from the control panel 5 is supplied to the extrapolation point calculation circuit 23 to discriminate the signal inside or outside the screen, and this discrimination signal is supplied to the crosshatch generator 2. The extrapolated points of the cursor are displayed. Therefore, as shown in the display screen diagram of FIG. 3, for example, adjustment points b and c
The cursor is displayed at, and the square cursor is displayed only at the d position at the adjustment point d on the screen. That is, the cursor is 1
The position of the adjustment point on the screen is displayed when only two are displayed, and the position of the adjustment point (extrapolation point) outside the screen is displayed when two cursors are displayed.

As described above, according to this embodiment, by presetting ON / OFF of the extrapolation point calculation for each input signal, the deflection amplitude of the receiver is overscanned and the adjustment points outside the screen are not displayed. In some cases, the extrapolation point display has cursors at two adjustment positions within the screen, and the extrapolation calculation can automatically perform adjustments outside the screen, and when the deflection amplitude of the receiver is an underscan image, Since extrapolation point calculation and extrapolation point display can be prohibited, overscan /
Even if the extrapolation points are inside or outside the screen due to underscan images, etc., optimum convergence adjustment can be performed in the optimum state according to the input signal.

(Embodiment 2) A second embodiment of the present invention will be described below with reference to the drawings.

FIG. 5 is a block diagram of a digital convergence device according to the second embodiment of the present invention. In FIG. 5, the difference from the first embodiment is that over / underscan 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 on the screen frame, 35 and 36 are comparators, 37 is a horizontal extrapolation point ON / OFF signal, and 38 is a vertical direction. Extrapolation point ON / OFF signal. Note that in FIG. 5, the components that operate in the same manner as in FIG. 1 and FIG. 7 of the conventional embodiment are denoted by the same reference numerals and the description thereof will be omitted.

The operation of the digital convergence device of this embodiment having the above-described structure 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 in the first embodiment, and therefore will be omitted. When the signal is input to the receiver and the horizontal amplitude is controlled by the deflection amplitude control circuit 33 to control the deflection circuit 17 to adjust the amplitude of the screen, the minus side voltage of the comparator 35 is changed. Since the reference voltage for deflection amplitude control in the case of 1 is applied to the + side of the comparator, whether the extrapolation point is inside or outside the screen can be determined by whether the voltage output from the comparator 35 is + or −. The extrapolation calculation in the horizontal direction is performed by the discrimination signal 37.
N / OFF. Similarly, in the vertical direction, the extrapolation calculation in the vertical direction is turned ON / OFF by the output of the comparator 36. In this way, by comparing the screen amplitude for each input signal with the reference amplitude, over / under scanning can be discriminated and the extrapolation calculation can be turned ON / OFF.

(Embodiment 3) A third embodiment of the present invention will be described below with reference to the drawings.

FIG. 6 is a block diagram of a digital convergence device according to the second embodiment of the present invention. In FIG. 6, the difference from the first embodiment is that over / underscan is determined by the frequency of the input signal. In FIG. 6, 39 is a horizontal synchronizing signal, 40 is a vertical synchronizing signal, 41 is a reference clock generator, 42 is a counter for counting the horizontal frequency, 43 is a minute period for lowering the frequency of the reference clock, and 44 is a vertical frequency. Counter, 4
Reference numeral 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 by the horizontal and vertical frequencies. In FIG. 6, the elements that operate in the same manner as in FIG. 1 and FIG. 7 of the conventional embodiment are denoted by the same reference numerals and the description thereof will be omitted.

The operation of the digital convergence device of this embodiment having the above-described structure 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 in the first embodiment, and therefore will be omitted. When a signal is input to the receiver, the horizontal synchronizing signal 39 is counted by the counter 42 by the reference clock input from the reference clock generator 41. The horizontal frequency determining circuit 45 determines the frequency of the horizontal synchronizing signal based on the counted data. Vertical sync signal 4
Similarly, for 0, the counter 44 counts the reference clock input from the reference clock generator 41 with the clock whose frequency is reduced by the division period 43. The frequency of the vertical synchronizing signal is determined by the vertical frequency determining circuit 45 based on the counted data. Based on the horizontal and vertical frequency data, the input signal discrimination circuit 47 discriminates over / under scanning, and outputs an extrapolation calculation ON / OFF signal,
Extrapolation calculation is automatically turned on / off.

In the first, second and third embodiments, the projection type color image receiver has been described for easy understanding, but it is also effective for the shadow mask type direct view type image 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 optimum digital convergence can be adjusted according to 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, the optimum digital convergence can be adjusted according to the input signal at the time of readjustment.
Highly accurate correction can be easily realized in a short time.

As described above, according to the present invention, the screen amplitude is discriminated and the extrapolation calculation is automatically turned ON / OFF, so that the optimum digital convergence can be adjusted according to the input signal. Highly accurate correction can be realized easily in time.

Further, according to the present invention, the over / under scanning is discriminated by performing the input signal discrimination circuit on the basis of the horizontal frequency and the vertical frequency, and the extrapolation calculation is automatically turned ON / OFF.
By automatically performing the OFF signal, optimum digital convergence can be adjusted according to the input signal, and high-accuracy correction can be easily realized in a short time.

[Brief description of 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 overscan / underscan determination circuit in the digital convergence device.

3A and 3B are views showing a display screen for explaining the operation of the embodiment.

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]

 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 Scan Number of lines detection unit 14 Number of adjustment points setting unit 15 Coefficient calculation unit 16 Output amplification unit 17 Deflection circuit 18 Convergence coil 19 Deflection coils 21 and 22 Multiplexer 23 Extrapolation point calculation circuit 24 Overscan / Underscan determination circuit 25 Vertical calculation circuit 26 Address Generator 27 Nonvolatile Memory 28 Memory Read Circuit 29 Extrapolation Calculation Switching Circuit 30 Crosshatch 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 cycle 45 horizontal frequency discrimination circuit 46 vertical frequency discrimination circuit 47 input signal discrimination circuit

Claims (4)

[Claims] 1. A means for generating a plurality of convergence adjustment points in the horizontal and vertical directions on the screen of a color television receiver and displaying the cursor, and correction data for each of the adjustment points within the screen are input to display them outside the screen. The correction data for each adjustment point is obtained by extrapolation from the correction data in the screen, and the means for displaying the cursor display of each adjustment point outside the screen at the adjustment point in the screen obtained by extrapolation and each adjustment point Means for digitally storing the convergence correction amount, means for reading the correction data from the storage means in synchronization with a synchronization signal input to the receiver, and amplification and correction for the read correction data. Means for supplying to the coil for detection, detection means for detecting whether the screen is underscan / overscan, and extrapolation interpolation calculation is turned on / off based on the detection result.
A digital convergence device comprising means for turning off. 2. The digital device according to claim 1, wherein the means for detecting whether the screen is underscan / overscan detects preset data stored together with the correction data in the 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 the screen of a color television receiver and displaying the cursor, and correction data for each of the adjustment points within the screen are input to display the data outside the screen. The correction data for each adjustment point is obtained by extrapolation from the correction data in the screen, and the means for displaying the cursor display of each adjustment point outside the screen at the adjustment point in the screen obtained by extrapolation and each adjustment point Means for digitally storing the convergence correction amount, means for reading the correction data from the storage means in synchronization with a synchronization signal input to the receiver, and amplification and correction for the read correction data. Means for supplying to the coil for detection, detection means for detecting whether the screen is underscan / overscan by the amplitude of deflection, and extrapolation interpolation calculation is turned on / off based on the detection result. A digital convergence device comprising: 4. A means for generating a plurality of convergence adjustment points in the horizontal and vertical directions on the screen of a color television receiver and displaying the cursor, and correction data for each of the adjustment points within the screen are input to display the data outside the screen. The correction data for each adjustment point is obtained by extrapolation from the correction data in the screen, and the means for displaying the cursor display of each adjustment point outside the screen at the adjustment point in the screen obtained by extrapolation and each adjustment point Means for digitally storing the convergence correction amount, means for reading the correction data from the storage means in synchronization with a synchronization signal input to the receiver, and amplification and correction for the read correction data. Means for supplying to the coil for detection, detection means for detecting whether the screen is underscan / overscan at the horizontal and vertical frequencies of the input signal, and extrapolation interpolation calculation based on the detection result. A digital convergence device comprising means for turning on / off the power supply.