JPH10164607A - Automatic digital convergence adjusting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make automatic convergence adjustment possible in a television adjusting process. SOLUTION: An arithmetic unit 4 stores the reference position data of the convergence amount at an adjusting point and phase adjusting data of each color and forms a convergence adjusting signal by using the position adjusting data as adjusting position data. The convergence of, for example, a projection tube 7R in a set 6 to be adjusted is adjusted by using the convergence adjusting signal and a cross hatch pattern of R color is displayed on the display screen of the set 6. A picture processor 3 forms measuring position data by detecting the center of gravity of the R-colored cross pattern at each adjusting point and the arithmetic unit 4 compares the measuring position data with the reference position data and corrects the adjusting position data by using the feedback amount corresponding to the difference between both data. Consequently, the R-colored cross hatch pattern is displayed on the display screen and similar measurement is again repeated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a digital automatic adjustment device for a deflection system and convergence, and more particularly to a digital automatic adjustment device suitable for use in a projection television receiver (hereinafter, referred to as a projection television).

[0002]

2. Description of the Related Art At present, a large screen is required in the television market, and among them, a projection television is becoming mainstream. In such a projection television, it is necessary to adjust each part. In particular, it is necessary to adjust a deflection system for adjusting the size, center position, linearity, inclination, etc. of a display screen (more precisely, a raster area), and to adjust color misregistration. The convergence adjustment for eliminating the misconvergence caused is the main adjustment, and conventionally, it is performed as follows.

(1) Adjustment of deflection system: In FIG. 11A, an operator first attaches a jig screen 101 to a display unit 100a of a set 100 of a projection television. The jig screen 101 is a screen on which a reference grating 101a is scribed as shown in FIG.
Thereafter, for example, a G (green) cross hatch pattern (lattice pattern) 102G is displayed on the display unit 100a as a reference color cross hatch pattern. And
As shown in FIG. 11C, which shows an enlarged range of P in FIG. 11A, the scribe line 101a and the cross hatch pattern 1 on the jig screen 101 are determined at predetermined points.
If there is a deviation from the 02G line, adjustment is made at that point while performing visual measurement so that they match.

In this way, predetermined points are adjusted, and when the scribe line 101a and the line of the cross hatch pattern 102G match at all points,
The size, center, and linearity of the raster area on the display screen are set to normal values, and the inclination of the raster area on the display screen disappears, and the adjustment of the deflection system ends.

(2) Misconvergence adjustment The display unit 100a of the set 100 from which the deflection system has been adjusted and the jig screen 101 has been removed as described above,
As shown in FIG. 11D, the worker displays the reference color cross hatch pattern 102G of G color, and at the same time,
Cross hatch pattern 1 of another color, for example, R (red) color
02R is displayed. Then, by expanding the range of Q in FIG. 11D, as shown in FIG. 11E, the cross hatch patterns 102G and 102G are determined at predetermined points.
If there is a deviation in R, the cross hatch pattern 102 of R color
An adjustment is made at that point while visually measuring the amount of misconvergence so that R matches the cross hatch pattern 102G of the reference color. By adjusting each point in this way, the adjustment of the R color is completed. Next, in the same manner, another color such as B
By displaying the (blue) color cross hatch pattern and the reference color cross hatch pattern and performing the same adjustment for each point, misconvergence adjustment is performed.

The adjustment of the misconvergence is performed by measuring the amount of misconvergence at each point by the operator while adjusting the crosshatch pattern of the adjusted color newly displayed on the crosshatch pattern of the reference color already adjusted on the screen. Is operated by operating a switch on the keyboard such that the two are matched. As a result, the magnitude of the current flowing through the convergence yoke for convergence correction of the corresponding color changes, and the display position of the cross hatch pattern changes at each point on the display unit 100a, and adjustment is performed.

[0007]

In the conventional adjustment method, the number of points to be adjusted (adjustment points) is extremely large, for example, 117 points, and the number of points to be adjusted is adjusted for each of the adjustment points and for each color. Requires a great deal of time.

Further, data is controlled by an LPF (low-pass filter) from the top of the circuit configuration in the set 100. When adjustment is performed at a certain adjustment point, not only the target adjustment point but also Since other adjacent adjustment points are also affected at the same time, it is necessary to adjust in consideration of the amount of movement due to the amount of misconvergence at the top, bottom, left and right adjustment points, and the adjustment work requires extremely skill. Become.

An object of the present invention is to provide a digital automatic adjusting apparatus which can solve such a problem and can always adjust the deflection system and the convergence with constant high accuracy.

[0010]

In order to achieve the above object, the present invention provides a method of acquiring display information of the entire display screen of a set to be adjusted by a plurality of high-sensitivity video cameras, and performing image processing on the acquired display information. The amount of misconvergence is measured, and the process of correcting the display state of the display information on the display screen according to the amount of misconvergence is repeated so that the amount of misconvergence disappears.

The measurement of the amount of misconvergence is performed at a plurality of predetermined adjustment points on the display screen, and a feedback coefficient corresponding to the position of the adjustment point on the display screen is set for each of the adjustment points. It is assumed that the adjustment amount for each adjustment point is based on the data obtained by multiplying the feedback coefficient corresponding to the measured misconvergence amount.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing an embodiment of a digital convergence automatic adjustment device according to the present invention,
1a, 1b, 1c are video cameras, 2 is a camera switch,
Reference numeral 3 denotes an image processing device, 4 denotes an arithmetic device, 5 denotes a convergence adjusting device (hereinafter, referred to as a digital converter adjusting device), 6 denotes a set of a projection type television to be adjusted (hereinafter, referred to as an adjusted set), and 6a denotes an adjusted set 6 Display screen, 7R is a projection tube of R color, 7G is a projection tube of G color, 7B is a projection tube of B color, 8
Is a convergence adjustment circuit.

In the figure, the set to be adjusted 6 has already undergone coarse adjustment of the deflection system in the state shown in the figure, and the digital-conversion adjusting device 5 is connected to the convergence adjusting circuit 8 of the set to be adjusted 6. Thereby, the video camera 1, the camera switch 2, the image processing device 3, the arithmetic device 4, and the digital controller adjustment device 5 are attached to the set to be adjusted 6,
The video camera 1 can take an image of the display screen 6a of the set to be adjusted 6 so that the convergence of the set to be adjusted 6 can be automatically adjusted.

In the set 6 to be adjusted, digital data for convergence adjustment for each of R, G, and B colors is stored in the convergence adjustment circuit 8 when the set is manufactured. These digital data represent the cross hatch pattern of the adjustment colors R, G, and B on the display screen 6a of the set 6 to be adjusted.
When the data is displayed on the display screen 6a, the predetermined representative points on the cross hatch pattern (hereinafter, referred to as representative adjustment points) are data for position adjustment for matching the specified positions on the display screen 6a. The digital data for position adjustment of all the adjustment points defined from the digital data of the representative adjustment points is generated, and the convergence current flowing through the convergence yokes of the projection tubes 7R, 7G, and 7B is controlled accordingly. By
Make sure that misconvergence is corrected.

As the representative adjustment points, for example, 13 points in the horizontal direction and 9 points in the vertical direction are set, for a total of 117 points.

In this embodiment, the position adjustment data is automatically set to an adjustment amount that eliminates such misconvergence of the display image. The setting is called convergence adjustment, and eliminating mis-convergence of the displayed image when using the set subjected to such convergence adjustment is referred to as mis-convergence correction.

The adjustment of the deflection system of the set 6 to be adjusted is the same as that of the conventional example described above, and the deflection current flowing through the deflection yoke is adjusted by adjusting the variable resistor using a G color cross hatch pattern. In this case, the convergence current based on the position adjustment data of the G color stored in the convergence adjustment circuit 8 of the set 6 to be adjusted is adjusted to the G color. To the projection tube 7G. By adjusting such a deflection system,
The representative adjustment point in the cross hatch pattern of the G color coincides with a predetermined point of the reference grid of the jig screen attached to the display screen 6a, and this is used as a reference for automatic convergence adjustment. Can be.

In the adjusted set 6 provided as shown in FIG. 1 and having already undergone deflection system adjustment, the convergence adjustment circuit 8 includes digital data for adjusting the position of the G color which does not require convergence adjustment, and convergence adjustment data. , That is, digital data for adjusting the positions of the R and B colors.

The arithmetic unit 4 has reference digital data (hereinafter referred to as a reference position) that defines the display position on the display screen 6a of the representative adjustment point on the crosshatch pattern displayed on the display screen 6a of the set 6 to be adjusted. Data)
Display screen 6 of the same representative adjustment point as the representative adjustment point defined by the reference position data on the cross hatch pattern of the adjustment color for which the convergence is to be adjusted
and display position data that defines the display position at a. As such display position data, position adjustment data of each adjustment color stored in the convergence adjustment circuit 8 of the set to be adjusted 6 is used.

Here, as the display position data, R,
The reference position data may be provided separately using the position adjustment data of each of the adjustment colors G and B. However, in this embodiment, it is not necessary to adjust the convergence for the G color, and the adjusted set 6 is not required. Convergence adjustment circuit 8
The position data of the representative adjustment point is detected from the cross hatch pattern of G color displayed on the display screen while adjusting the convergence with the position adjustment data of G color stored in This is the reference position data.

In automatic adjustment of convergence, a cross hatch pattern of a predetermined adjustment color is displayed on the display screen 6a of the set 6 to be adjusted, and the arithmetic unit 4
The reference position data is set as described above, and the position adjustment data of the adjustment color for the displayed cross hatch pattern is read from the convergence adjustment circuit 8. Then, digital convergence data (hereinafter referred to as digital control data) for all the adjustment points is created from the position adjustment data, and the digital conversion data is supplied to the digital control adjustment device 5, whereby the cross hatch pattern displayed on the display screen 6a is displayed. Adjust convergence. A display screen of the convergence-adjusted cross hatch pattern is captured by the video camera 1,
From the output video signal of the video camera 1, the image processing device 3 detects the display position of the representative adjustment point of the displayed cross hatch pattern.

The arithmetic unit 4 also detects a difference between the display position of the representative adjustment point detected by the image processing unit 3 and the display position of the representative adjustment point specified by the reference position data, and responds to the difference. The above initial position data is corrected, the corrected position adjustment data is created, and the digicon data is created based on the corrected data. The convergence adjustment of the cross hatch pattern displayed by the new digicon data is performed. . The display screen 6a of the newly-converged adjusted cross-hatch pattern is again imaged by the video camera 1, and as described above, the representative adjustment point and the reference position of the cross-hatch pattern detected from the output video signal of the video camera 1. If there is a deviation from the display position of the representative adjustment point specified by the data, the above-mentioned digital control data is corrected again.

This operation is repeated until the representative adjustment point of the displayed cross hatch pattern detected by the arithmetic unit 4 matches the display position of the representative adjustment point specified by the reference position data. When the convergence adjustment operation for the cross hatch pattern of one adjustment color is completed, a similar operation is performed for the other adjustment color. Then, the corrected position adjustment data for each adjustment color is stored in the convergence adjustment circuit 8 of the set to be adjusted 6, and thereafter, for correcting misconvergence when the adjusted set 6 is used by the user. Used to create digital control data.

In this embodiment, the convergence of the set to be adjusted 6 is automatically adjusted by roughly operating as described above. Next, referring to FIG.
The operation and each unit will be described in more detail.

First, the convergence adjusting circuit 8 of the set 6 to be adjusted whose deflection system has been adjusted is adjusted by the digital converter adjusting device 5.
Connect to Then, the projection tube 7G of G color is driven by a pattern generator (not shown) to display the cross hatch pattern of G color on the display screen 6a of the set 6 to be adjusted, and the convergence adjustment circuit 8 stores the G color stored therein. From the position adjustment data, and corrects misconvergence in the G cross-hatch pattern displayed on the display screen 6a based on the digital control data. The G color cross hatch pattern is read by the video camera 1 and the output video signal is supplied to the image processing device 3 via the camera switch 2 so that the representative adjustment point of the G color cross hatch pattern is obtained. Position data is detected as measurement data. This measurement data is supplied to the arithmetic unit 4 (Step 100).

As described above, the measurement data is used as reference position data in the convergence adjustment of the adjustment colors other than the G color, that is, the R and B colors. There is a difference in the accuracy of the measurement due to differences in the measurement pattern, white balance adjustment, brightness adjustment, focus adjustment, regulation adjustment, and convergence adjustment between visual and video camera measurements. Then, the reference position data for the adjusted color to be adjusted for convergence is formed by adjusting the offset value (step 101) (step 102). Here, first, it is assumed that the convergence adjustment is performed on the adjustment color R.
This reference position data is for the R color. The same applies to the adjustment color B.

After the setting of the reference position data in the arithmetic unit 4 is completed, the position adjustment data of the R color of the convergence adjustment circuit 8 of the set 6 to be adjusted is read as adjustment color data (step 103, 104), based on the adjustment amount of the adjustment color data at the representative adjustment point, a predetermined point between the representative adjustment points (hereinafter referred to as an intermediate adjustment point. There is one or more intermediate adjustment points between the representative adjustment points). The amount of adjustment in (1) is obtained by interpolation, and position adjustment data for all adjustment points, that is, digiton data, consisting of the adjustment amount at the intermediate adjustment point and the adjustment amount at the representative adjustment point is formed.
This digital control data is stored in the digital control adjusting device 5 (step 106). At this time, the digital control data of the R color is held in the arithmetic unit 4 as it is.

At the same time, the projection generator 7R for the R color, which is one of the adjustment colors, is driven by the pattern generator, and the digital control data for the R color stored in the digital converter adjustment device 5 is used to adjust the convergence of the set 6 to be adjusted. The convergence current of the convergence yoke of the R color projection tube 7R is supplied to the circuit 8 to control the convergence current on the display screen 6a according to the R color digital conversion data. Is displayed.

By interpolating the intermediate adjustment points, the adjustment points of the digital control data are, for example, 13 points in the horizontal direction and 256 points in the vertical direction.

The display screen 6a on which the R hatch pattern is displayed is picked up by the video camera 1.

The video camera 1 is a high-sensitivity camera,
Usually, 4 to 9 pieces are used, but here, it is assumed that 9 pieces are used. The display screen 6a of the set to be adjusted 6 is divided and imaged by these video cameras 1. That is, when nine video cameras 1 are used as shown in the figure, the display screen 6a is divided vertically and horizontally into three parts, that is, nine parts in total, and each divided area is observed by a separate video camera 1. On the display screen 6a of the set 6 to be adjusted, the cross hatch pattern of the R color is displayed as described above, and the nine video cameras 1 share and display the display screen 6a.

The output video signal of the video camera 1 is sequentially switched and selected by the camera switch 2 and supplied to the image processing device 3 as a visual sensor. In the image processing device 3, a predetermined area defined for each adjustment point is extracted from the supplied video signal, image processing for detecting the position of the center of gravity is performed in each part, and the R color displayed is displayed. The calculation for detecting the position of the center of gravity of the line image at the representative adjustment point of the cross hatch pattern is performed.

Such processing is performed on the output image signals of all the video cameras 1 by switching of the camera switching unit 2, whereby the processing of the output video signals of all the video cameras 1 is performed and all the representative adjustments are performed. When the position of the center of gravity at the point is detected, data of the position of the center of gravity of all representative adjustment points on one screen (hereinafter, referred to as measurement position data) is obtained, and supplied to the arithmetic unit 4 including a personal computer.
The above processing operation is step 107.

The arithmetic unit 4 compares the measured position data and the reference position data corresponding to each representative adjustment point (step 108) to determine the amount of misconvergence (step 109). It is determined whether or not the convergence amount is within a predetermined specification (step 110). If the convergence amount deviates from the specification set for this representative adjustment point at any of the representative adjustment points, this mistake is determined. The convergence amount is multiplied by a feedback coefficient set in advance for the representative adjustment point to create additional data for correction (steps 111, 112, 11).
3) The adjusted color data is corrected by adding the added data to the held adjusted color data (step 105).

Then, the operation from step 106 is performed again on the basis of the corrected adjustment color data, and thereafter, similarly, the misconvergence amounts at all the detected representative adjustment points are within the corresponding specifications. Is repeated, and the adjustment color data is sequentially corrected by repeating a series of operations of steps 106 to 113 and 105.

When the misconvergence amounts at all the detected representative adjustment points fall within the corresponding specifications (step 110), the convergence adjustment for the R color is completed. The adjustment color data of the R color obtained by the arithmetic unit 4 at this time is sent to the convergence adjustment circuit 8 in the adjusted set 6 as the position adjustment data of the R color, and the position adjustment data of the position adjustment data before the convergence adjustment is adjusted. Stored instead.

Next, the G cross-hatch pattern corrected for the misconvergence is displayed on the display screen 6a again. The video camera 1 takes an image of the cross hatch pattern. As described above, the measurement data of G color is formed (Step 10).
0). An offset value for the B color projection tube 7B is added to this measurement data (Step 101), and B color reference position data is formed (Step 102). In addition,
The measurement data of G color obtained in step 100 is stored in the arithmetic unit 4 for the difference in the convergence adjustment of R color,
This may be used to create the B color reference position data.

The processing thereafter is the same as that for the R color, and the arithmetic unit 4 obtains the adjusted color data of the B color in which the amount of misconvergence at all representative adjustment points falls within the specification. The adjustment color data is stored as B color position adjustment data in the convergence adjustment circuit 8 of the set to be adjusted 6 instead of the B color position adjustment data before the convergence adjustment.

As described above, when the automatic adjustment of the convergence is completed, the set 6 to be adjusted is separated from the digital-conversion adjusting device 5. When the convergence-adjusted set 6 is subsequently used, misconvergence is corrected using the R, G, and B color position adjustment data stored in the convergence adjustment circuit 8.

When the reference position data is formed from the G cross hatch pattern, the position of the center of gravity is detected for the representative adjustment point as described above.

Here, the adjustment of the deflection system of the set 6 to be adjusted will be described.

As described above, the convergence adjustment circuit 8 of the unadjusted set 6 stores the position adjustment data of the R, G, and B colors obtained by calculation in advance. Similar to the conventional example described with reference to FIG. 11, a jig screen is attached to the display screen 6a of the set 6 to be adjusted, the projection tube 7G of G color is driven by the pattern generator, and stored in the convergence adjustment circuit 8. The convergence correction current according to the position adjustment data of the G color is supplied to the convergence yoke, and the display screen 6a displays the G cross hatch pattern as the reference color.
In such a display state, the resistance value of the variable resistor is adjusted to adjust the deflection current flowing in the deflection yoke of the projection tube 7G, so that the G cross hatch pattern coincides with the reference grid inscribed on the jig screen. I do.

The deflection system is adjusted in this manner, and the G color position adjustment data stored in the convergence adjustment circuit 8 of the adjusted set 6 after the deflection system adjustment is used as the reference position data in the convergence adjustment. Are used to correct misconvergence of the G color crosshatch pattern.

FIG. 3 is a block diagram showing a specific example of the convergence adjusting circuit 8 in FIG. 1 together with the arithmetic unit 4 and the digital converter adjusting unit 5, where 5a is an SRAM (static RAM), 8a is a CPU, and 8b is an EEPROM.
(Electrically erasable programmable ROM), 8c is SRAM, 8d is a changeover switch, 8e is a gate array,
8f is a D / A (digital / analog) converter, 8g is L
PF, and parts corresponding to those in FIG. 1 are denoted by the same reference numerals.

In the figure, in the set to be adjusted 6, R, G, and R are stored in the EEPROM 8b of the convergence adjusting circuit 8.
Position adjustment data for the B cross hatch pattern is stored. When the G cross cross hatch pattern is displayed on the display screen 6a (FIG. 1) and the deflection system is adjusted, the CPU 8a reads the data from the EEPROM 8b. The position adjustment data of G color is read out, and the position adjustment data of the intermediate adjustment point is interpolated into digital control data and stored in the SRAM 8c in the same manner as the arithmetic unit 4 (FIG. 1). At this time, the CPU 8a closes the changeover switch 8d to the SRAM 8c side and reads out the digital control data stored in the SRAM 8c. The read digital control data is supplied to the gate array 8e controlled by the CPU 8a.
After being selected on the G channel side and converted to analog convergence data by the D / A converter 8f, the LPF 8g
And controls the convergence correction signal supplied to the projection tube 7G (FIG. 1) through the convergence yoke.
As a result, the G cross-hatch pattern corrected to the convergence correction current is projected on the projection tube 7G, and is displayed on the display screen 6a, and the deflection system is adjusted as described above.

Next, the convergence adjustment is performed in the same manner as in the deflection system adjustment.
A cross hatch pattern of G color corrected for misconvergence based on the position adjustment data of G color stored in b is displayed on the display screen 6a of the adjusted set 6,
Thereby, the arithmetic unit 4 obtains the reference position data of the adjustment color as described above.

Thereafter, the CPU 8a sets the EEPROM 8
The arithmetic unit 4 reads out the position adjustment data of the R color from b.
And switches the changeover switch 8d to the SRAM 5c side of the digital controller adjustment device 5. And the arithmetic unit 4
As described above, the digital data of R color is formed,
When written into the SRAM 5a of the digital controller adjustment device 5,
The CPU 8a reads this, supplies it to the gate array 8e via the changeover switch 8d, and selects the R channel. The selected R color digital conversion data is converted into analog convergence data by the D / A converter 8f, and supplied to the R color projection tube 7R (FIG. 1) via the LPF 8g. In the projection tube 7R, the convergence correction current flowing through the convergence yoke is controlled by the supplied convergence data. As a result, the display screen 6a of the adjusted set 6 has the SRAM 5a
The cross hatch pattern of the R color, which is adjusted for the convergence by the digital conversion data of the R color stored in the R, is displayed.

As described above, when the arithmetic unit 4 obtains the adjustment color data such that the amount of misconvergence at all the representative adjustment points of the R color falls within the specification, the adjustment color data is processed by the CPU 8a. The read adjustment position data is rewritten with the adjustment position data before adjustment in the EEPROM 8b as new adjustment position data.

The same applies to the position adjustment data for the B color. When the convergence adjustment of the set to be adjusted 6 is completed, the set to be adjusted 6 is disconnected from the digital-conversion adjusting device 5, and at the same time, the CPU 8a sets the changeover switch 8d to the S position.
Switch to the RAM 8c side. In this case, EEPRO
M8b stores the corrected R and B color adjustment position data and the G color position adjustment data used to create the reference position data.

When the adjusted set 6 is used by the user, the CPU 8a reads out the position adjustment data from the EEPROM 8b and interpolates the position adjustment data at the intermediate adjustment point as in the arithmetic unit 4 for each. To form digital control data and store it in the SRAM 8c. These R, G, B color digital data are stored in SRAM.
8c, is supplied to the gate array 8e via the changeover switch 8d, is respectively distributed to the R, G, and B channels, is converted into analog convergence data by the D / A converter 8f, and is respectively converted via the LPF 8g. It is supplied to the projection tubes 7R, 7G, 7B in FIG. These projection tubes 7
In R, 7G, and 7B, the convergence correction current flowing through the convergence yoke is controlled according to the analog convergence data. Thereby, the display screen 6a
A color image in which misconvergence is corrected is displayed.

FIG. 4 is a diagram showing an operation of detecting the center of gravity of the image processing apparatus 3 in FIG. 1, wherein 8R is a cross hatch pattern of R color and 9 is one of the video cameras 1 (hereinafter referred to as a video camera 1a). 10H, 10
V is a window, and portions corresponding to FIG. 1 are denoted by the same reference numerals.

In FIG. 4A, a cross hatch pattern 8R of R color is now displayed on the display screen 6a of the set 6 to be adjusted, and the video camera 1a (FIG. 1) captures an image pickup area 9 of the display screen 6a. It shall be.

FIG. 4B is an enlarged view of the image pickup area 9, and a video signal obtained from the video camera 1 a represents an image of the image pickup area 9. Windows 10H and 10V including the representative adjustment point are set in the image processing device 3, and first, a portion in the window to which the supplied video signal is applied is extracted. The horizontal adjustment window 10H is provided to cross the horizontal line of the cross hatch pattern 8R, and the vertical adjustment window 10V is provided to cross the vertical line of the cross hatch pattern 8R. . The windows 10H and 10V are set to have such a length that the cross hatch pattern 8R always crosses them even if misconvergence occurs.

FIG. 4C shows the window 1 in FIG. 4B.
FIG. 4D shows the pattern and the extracted signal in the window 10V in FIG. 4B, respectively.

In FIG. 4C, a part of the horizontal line portion 8RH of the cross hatch pattern 8R is included in the window 10H, and the extracted signal 11H in the window 10H extends in the length direction of the window 10H. look,
A peak occurs at a part of this horizontal line portion 8RH of the cross hatch pattern 8R. Therefore, by comparing with an appropriately set threshold value SH, this peak portion hatched by oblique lines, that is, a part of the horizontal line portion 8RH of the cross hatch pattern 8R crossing the window 10H is detected. Then, the position of the center of gravity of the detected portion is obtained by calculation, and this is set as the vertical position of the representative adjustment point of the cross hatch pattern 8R. If this position of the center of gravity coincides with a specific position in the window 10H, for example, the center position, there is no misconvergence at this representative adjustment point. This is determined by comparison with the reference position data in the arithmetic unit 4 (FIG. 1).

In FIG. 4D, the same applies to the window 10V. The vertical line portion 8RV of the cross hatch pattern 8R in the window 10V is
By comparing the extracted signal 11V within 0V with an appropriately set threshold value SV, it is detected as a hatched portion with diagonal lines, and the position of the center of gravity is obtained by calculation to obtain the horizontal position at the adjustment point.

The threshold values SH and SV are not fixed, but can be automatically and appropriately changed according to the surrounding environment. For example, in the adjustment step, when external light or the like enters the video camera 1, the video camera 1
The level of the video signal output from is increased. At this time, if the thresholds SH and SV are fixed, FIG.
In the center of gravity detection processing described in (d), accurate detection processing cannot be performed. For this reason, for example, the surrounding brightness is detected, and the threshold values SH and SV can be increased according to the detection output as shown in FIG.
When the screen of the set 6 to be adjusted is dark, the level and amplitude of the output video signal of the video camera 1 become small, and the threshold S
If H and SV are fixed, the center-of-gravity detection processing cannot be performed accurately. For this reason, a sensor for detecting the brightness of the screen of the set 6 to be adjusted is provided, and according to the detection output, as shown in FIG.
Try to lower V.

Next, a specific example of a method of detecting the position of the center of gravity of the adjustment point in the windows 10H and 10V based on the above detection results will be described with reference to FIG.

Referring to FIG. 11, the window 10H for horizontal adjustment will now be described.
It is assumed that an extracted signal 11H having an intensity distribution as shown in FIG. Here, the horizontal axis of the distribution chart represents the position x from the reference position 0, and the vertical axis represents the intensity g (x) of the extracted signal 11H.

The window 10H is positioned horizontally at positions xp to
xq, and this position is divided by the sub-pixel fineness (for example, in the display screen of a 50-inch projection television, one pixel (one pixel) is one pixel).
mm, and the sub-pixel in this case can be set to about 1/10 of about 0.1 mm).

As one method for obtaining the position of the center of gravity of the extracted signal 11H, that is, the position of the adjustment point,
The following equation 1 according to the weighted average method:

[0062]

(Equation 1)

Is obtained by calculating However, as described above, as shown in FIG. 5, when the horizontal range of the window 10H is the positions xp to xq, the sum Σ is x = x
This is performed for p to xq.

As described above, when the position of the representative adjustment point is detected by the center-of-gravity calculation, the measurement reproduction accuracy is set to the sub-pixel accuracy (0.1 m for a 50-inch projection television).
It is possible to measure the position of this representative adjustment point with an accuracy of about m subpixels).

Next, the interpolation operation (step 106 in FIG. 2) in the arithmetic unit 4 (FIG. 1) will be described.

Here, for the sake of simplicity, the representative adjustment points are assumed to be five adjustment points on the display screen 6a, and the convergence adjustment amounts of the other adjustment points are interpolated from these convergence adjustment amounts. And

Now, the representative adjustment points are, for example, 5 points A, which are the four corners of the display screen 6a and the specified center of gravity position in the window shown in FIG.
B, C, D, and E, the position A of such representatives adjustment points, B, C, D, E respectively _{X A, X B, X C} , X D, X E, the convergence adjustment amount at their f ( X _A ), f (X _B ), f (X _C ), f (X _D ), f
Assuming that (X _E ), the convergence adjustment amount f (x) at an arbitrary point x on the display screen 6a is calculated using a newly developed interpolation method based on Lagrange interpolation in order to realize high-speed high-order curve interpolation. By

[0068]

(Equation 2)

Is expressed as follows.

Here, assuming that the number of adjustment points on the display screen 6a on which the convergence adjustment amount is to be set is 256, a0 (x), a1 (x), a2 (x), a3 (x), a4
(x) is a set of five adjustment points x0, x1, x2, x
3, x4 are set for each of the adjustment points, and the values are different for each of the adjustment points, but a0 (x), a1 (x),
a2 (x), a3 (x), a4 (x) are constant values determined by the position x.

Therefore, a0 for each adjustment point
(x), a1 (x), a2 (x), a3 (x), a4 (x) is the CP of the arithmetic unit 4
U, and at the time of the interpolation calculation, the position x of the adjustment point to be interpolated and the corresponding a0 (x), a1 (x), a2
A set of (x), a3 (x), a4 (x) is read out, and by using this, the interpolation operation of the above equation 2 is performed, whereby the convergence adjustment amount f (x) at the adjustment point at this position x is obtained. Can be requested. In this way, the speed of the interpolation calculation is increased.

As shown in FIG. 3, the convergence adjustment circuit 8 passes the analog convergence data through the LPF 8g to generate 256 digital adjustment data even if the digital control data has 256 adjustment points. The space between the points is filled to be a convergence adjustment signal for all points.

Next, the specifications and feedback coefficients in FIG. 2 will be described.

Since the projection type television has a special structure and a special display system (rear projection), a unit convergence is set for each color, each channel (horizontal and vertical), and each point on the display screen. The moving amount of the display point on the display screen with respect to the adjustment amount is different. Here, the amount of movement with respect to the change of the least significant bit of the digital control data at the display point on the display screen is defined as the resolution. The larger the resolution, the larger the amount of movement of the display point on the display screen with respect to the same size of digicon data. Therefore, if the required amount of convergence adjustment is the same, the larger the resolution, the greater the position of the digicon data. The amount of data will be reduced.

Now, as shown in FIG. 6A, 13 × 7 adjustment points at equal intervals are set on the display screen 6a of the set 6 to be adjusted, and an example of the resolution at each adjustment point is shown. As shown in FIG. 6B, the resolution is not uniform on the display screen 6a. As an example, 0.3-1.0m
There is a variation of about m.

The specification and the feedback coefficient are defined as follows: spec = resolution / 2 feedback coefficient = 1 / resolution. FIG. 6C shows specifications for the resolution shown in FIG. 6B, and FIG. 6D shows feedback coefficients for the resolution shown in FIG.

In this embodiment, the specification and the feedback coefficient are independently set for each adjustment point on the display screen, and are formed at step 113 in FIG. 2 at each adjustment point. Correction addition data is formed according to the feedback coefficient. Accordingly, at a position where the resolution is large, the feedback coefficient is small, so that the added data for correction becomes small, and fine adjustment of misconvergence becomes possible. This makes it possible to increase the accuracy and speed of the convergence adjustment.

Further, since such a setting can be made automatically, it can be set easily and in a short time even when a new model is produced.

By the way, on the production line, the set 6 to be adjusted is often not positioned, and is displaced on the base plate in the front-rear direction or the left-right direction as viewed from the video camera (hereinafter, referred to as In many cases, the display screen is not facing the front with respect to the video camera, but is inclined. When the set to be adjusted is displaced or inclined as described above, when the convergence adjustment is performed using the plurality of fixed video cameras 1 as described above, the imaging conditions of the display screen 6a by the video cameras 1 are changed. Therefore, the data of the correct adjustment point in the displayed cross hatch pattern cannot be detected, and the correct convergence adjustment cannot be performed. Normally, the positional deviation and inclination of the set 6 to be adjusted on the base plate in the front-rear, left-right directions are about 10 cm.

In this embodiment, the convergence adjustment is performed after the positional deviation and inclination of the set to be adjusted are detected and corrected for them. A description will be given of the correction of the displacement and the inclination of the set 6 to be adjusted.

However, here, it is assumed that four video cameras 1 are used, and each of them takes a divided image of the display screen 6a of the set 6 to be adjusted. The set to be adjusted 6 and the video camera 1 are assumed to be placed horizontally, and the above-described “tilt”
Means that the display screen 6a of the set to be adjusted 6 is the video camera 1
Does not face the front.

As shown in FIG. 7 (a), each video camera 1 is set so that the imaging areas 12a, 12b, 12c, and 12d of each video camera 1 partially overlap each other at respective sides. When the set 6 to be adjusted is conveyed on the production line and is set at a predetermined position, these four video cameras 1 move to the respective imaging areas 12a and 12a.
b, 12c, and 12d, the display screen 6a of the set to be adjusted 6 is imaged, and the respective imaging regions 12a, 12b, and 12 are imaged.
The position of the adjustment point on the display screen 6a in c and 12d is obtained.

For this purpose, first, the center position Q on the display screen 6a of the set 6 to be adjusted is detected, and based on this, one of the display screens 6a in the image pickup area 12 of each video camera 1 is detected.
The position of the / 4 part is detected.

For this purpose, as shown in FIG. 8, a reference set of the same model as the set 6 to be adjusted is arranged facing the front of the video camera 1 and its display screen 6a 'is displayed on the video camera.
Is imaged. As shown in the drawing, a center marker M is displayed at the center position of the display screen 6a 'of the reference set, and this center marker M is displayed in the imaging regions 12a, 12b, 12c, and 12d of all the video cameras 1. The reference set is set at a defined position to include.

The output image signal of each video camera 1 is processed, whereby the center marker M is detected to detect its position in each of the imaging regions 12a, 12b, 12c, 12d, 12c, a horizontal line display screen 6a 'passing through the center marker M
The position of a point b intersecting with the side of is calculated, and the distance L _H1 between the position of the center marker M and the position of the point b is calculated. Similarly, for the imaging regions 12b and 12d, a display screen 6a 'of a horizontal line passing through the center marker M is displayed.
The position of a point d that intersects the side of is calculated, the distance L _H2 between the position of the center marker M and the position of this point d is calculated, and the ratio L _H1 : L _H2 of these distances is calculated and held. I do.

Further, regarding the imaging regions 12a and 12b,
The position of a point a where a vertical line passing through the center marker M intersects with the side of the display screen 6a 'is determined, and the distance L _V1 between the position of the center marker M and the position of this point a is calculated. Similarly, for the imaging areas 12c and 12d, the position of the point c where the vertical line passing through the center marker M intersects with the display screen 6a 'is determined, and further, the position between the position of the center marker M and the position of this point c is determined. The distance L _V2 is calculated and the ratio L _V1 : L _V2 of these distances is calculated and held.

In this case, if the conditions such as the distance and the magnification of each video camera 1 to the reference set are completely equal, L _H1 :
It goes without saying that L _H2 = L _V1 : L _V2 = 1: 1.

When the reference data of the ratio is obtained, the video camera 1 is then turned on, as shown in FIG.
The set 6 to be adjusted is set at a predetermined position on the front surface of the display screen 6a, and a dot Q 'is displayed near the center of the display screen 6a. Since it is very difficult to accurately display this dot Q at the center position, this dot is displayed at the center position by the adjustment described below.
The processing for detecting the center position a is performed.

That is, each video camera picks up an image of the display screen 6a on which the dot Q is displayed, and first detects the position of the dot in each of the image pickup areas 12a, 12b, 12c, and 12d. Then, the imaging regions 12a, 12
As for c, a horizontal line passing through the dot Q is displayed on the display screen 6.
The position of a point B that intersects the side of a is obtained, and the distance l _H1 between the position of the point B and the position of the dot Q is obtained. This is the same process as _obtaining the distance L _H1 in the reference set shown in FIG.
For 12d, the position of the point D where the horizontal line passing through the dot Q intersects the side of the display screen 6a is determined, and further, the distance l _H2 between the position of the point B and the position of the dot Q is determined.
Then, the ratio l _H1 : l _H2 is determined.

Since the set to be adjusted 6 is the same model as the above-mentioned reference set, if the dot Q is displayed at the center position of the display screen 6a, then _lH1 : _lH2 = _LH1 : _LH2 .
If these ratios are not equal, the display position of the dot Q is displaced in the direction corresponding to the horizontal ratio l _H1 : L _H2 on the display screen 6a, and the same operation is repeated. And l _H1 : l _H2 =
When L _H1 becomes L _H2 , the horizontal position of the dot Q is defined to be regular, and then the vertical position of the dot Q is adjusted.

The same applies to the vertical position adjustment of the dot Q. That is, for the imaging regions 12a and 12b, the dot Q
Is determined at a point A where a vertical line passing through the line intersects the side of the display screen 6a, and a distance l between the point A and the dot Q is determined.
_{Find V1} . Further, regarding the imaging regions 12c and 12d,
Point C at which the vertical line passing through dot Q intersects the side of display screen 6a
Is obtained, and a distance l _V2 between the position of the point C and the position of the dot Q is obtained. Then, the ratio l _V1 : l _V2 = L _V1 : L
It is determined whether it is _V2 , and the display position of the dot Q is adjusted in the vertical direction until this is satisfied.

With the above adjustment, the dot Q is displayed at the center position of the display screen 6a as shown in FIG. 7B. Hereinafter, this center position is expressed as Q.

At this time, the positions of the points A, B, C, and D have been determined. Therefore, as shown in FIG. 7C, the point at which the vertical line passing through the point A intersects the two sides of the display screen 6a is determined. P1, respectively
P2, and a vertical line passing through the point D and 2 of the display screen 6a.
The points that intersect the sides are P3 and P4, respectively,
The positions of P2, P3, and P4 are obtained. In this case, when the display drawing 6a is not facing the front with respect to the video camera 1 and is inclined, the height of the right side and the height of the left side of the display screen 6a are slightly different, and From the video camera 1, it looks like a trapezoid in the horizontal direction. Therefore, the points P1 to P4 are obtained as points where a vertical line passing through the points A and D intersects the side of the display screen 6a.

Thus, in each of the imaging regions 12a to 12d,
For example, the imaging area 12a will be described with reference to FIG.
As shown in (d), an area surrounded by points Q, A, P1, and B is an imaging area of the display screen 6a shared by the video camera 1 having the imaging area 12a. Then, for example, the point P1 at the upper left corner of the display screen 6a is a reference position of the display screen 6a, and the position of the adjustment point on the display screen 6a is displayed based on the reference position.

The above description uses four video cameras 1 and
In the case where the display screen 6a is divided into four parts and the image is captured, for example, when nine video cameras 1 are used and the display screen 6a is divided into nine parts and the image is captured, as shown in FIG. One adjacent imaging region partially overlaps each other, and the four imaging regions 12a, 12b, 12d, 1
The dot Q1 is set in the area where 2e overlaps, and the imaging area 12b, 1
A dot Q2 is placed in an area where 2c, 12e and 12f overlap, a dot Q3 is placed in an area where the imaging areas 12d, 12e, 12g and 12h overlap, and the imaging areas 12e, 12f, 12h and 12h are placed.
The dots Q4 are respectively displayed in the area where i overlaps, and the positions of the dots Q1, Q2, Q3, and Q4 are adjusted in the same manner as described above to determine the area of the display screen 6a shared by each video camera 1. Can be.

As described above, the area of the display screen 6a in the imaging area of each video camera 1 is determined. Next, it is necessary to define the position of each part in this area. This is represented by points Q, A, P shown in FIG.
A description will be given by taking a region defined by 1, B as an example.

Also in this case, using the reference set used in the description of FIG. 7, the position of each point is defined for the partial area of the display screen 6a 'imaged by the video camera 1 having the image area 12a. The position of each point of the area on the display screen 6a in the imaging area 12a of the set to be adjusted 6 is defined based on.

That is, the partial area 13a 'of the display screen 6a' imaged by the video camera 1 having the image area 12a is shown in FIG.
In the case of 0 (a), a predetermined number of positions indicated by ● points in the partial area 13a 'are defined as coordinate positions (x', y ') from the center position Q. These positions may be the representative adjustment points described above.

Now, it is assumed that the positions are arranged in m rows in the horizontal direction (x direction) and in n columns in the vertical direction (y direction). The horizontal width of the partial region 13a 'is X, and the width of the right side is X. Is Y1 ′, and the width of the left side is Y1 ′. So, for example,
Considering the position P ′ of the second column in the horizontal direction and the second column in the vertical direction from the center position Q, the coordinate x ′ in the horizontal direction is x ′ = 2 × X ′ / (m + 1). On the other hand, the vertical width Y3 'passing through the position P' of the partial region 13a 'is represented by Y3' = Y1'-2 (Y1'-Y2 ') / m, and the vertical coordinate y' of the position P 'is obtained. Becomes y ′ = 2 · Y3 ′ / (n + 1). That is, generally, i
Coordinates (x ', y') of position P 'in the column, j-th column in the vertical direction
X ′: X ′ = i / (m + 1): 1, y ′: Y3 ′ = j /
(N + 1) holds.

Under such a premise, the position P defined in FIG. 10A for the partial area 13a as shown in FIG. 10B in the imaging area 12a on the display screen 6a of the set 6 to be adjusted. ', The position P is defined. this is,
It is defined as follows.

Assume that the horizontal width of the partial area is X,
P is a position corresponding to the position P ′ at 0 (a), and this position P
Assuming that the width of the partial area 13a passing through
Are defined so as to satisfy x: X = x ′: X ′, y: Y3 = y ′: Y3 ′. Note that Y3 = Y1-2 (Y1-Y2) / m.

In this manner, each position P of the partial area 13a is defined, and the previously detected center of gravity position and the like are detected with reference to these positions P. Also, as shown in FIG. The positions of the windows 10H and 10V are determined.

In the description with reference to FIG.
The vertical widths Y3 and Y3 'passing through the positions P and P' to be defined are used as the vertical widths of the 3a and 13a '. This is because the reference set may not face the video camera 1 in some cases, and the display screens 6a and 6a 'may be seen from the video camera 1 as trapezoids. In this case, of course, the set to be adjusted and the reference set are accurately placed on a horizontal surface.

In the description of FIG. 10, the defined positions P and P 'are arranged at regular intervals in the horizontal and vertical rows, but this is not necessarily the case. .

[0105]

As described above, according to the present invention,
It is possible to improve the productivity of the entire line and make the quality uniform by the automatic adjustment and the high speed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a digital convergence automatic adjustment device according to the present invention.

FIG. 2 is a flowchart showing the operation of the embodiment shown in FIG.

FIG. 3 is a block diagram showing a specific example of a convergence adjusting device in FIG. 1;

FIG. 4 is a diagram showing a specific example of a gravity center detection processing operation by the image processing device in FIG. 1;

FIG. 5 is a diagram showing a specific example of a method of detecting the position of the center of gravity from the detection signal in the window in FIG.

FIG. 6 is an explanatory diagram of specifications and feedback coefficients set by the arithmetic device in FIG. 1;

FIG. 7 is an explanatory diagram of a method of detecting a positional shift and a tilt of an adjusted set when there are four video cameras.

8 is an explanatory diagram of a method for obtaining data necessary for detecting a positional shift and a tilt of the set to be adjusted shown in FIG. 7;

FIG. 9 is an explanatory diagram of a method of detecting a positional shift and a tilt of an adjusted set when the number of video cameras is nine.

FIG. 10 is an explanatory diagram of a method of defining each position on a display screen of an adjusted set as viewed from each video camera.

FIG. 11 is an explanatory diagram showing an example of a conventional deflection system and a method of adjusting convergence.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Video camera 2 Camera switcher 3 Image processing device 4 Arithmetic device 5 Convergence adjustment device (Digicon adjustment device) 6 Set to be adjusted 7R, 7G, 7B Projection tube 8 Convergence adjustment circuit

Claims (4)

[Claims] 1. A three-dimensional displacement (tilt, front-rear, left-right direction, etc.) of a set to be adjusted is determined based on a predetermined geometrical frame and a geometric relative value with a reference display position. From the frame measured at the start of adjustment of the set to be adjusted,
A first means for obtaining a reference adjustment position of each adjustment point on a target full screen; a second means for obtaining a deviation amount between the measured measurement adjustment position and the reference adjustment position of each point of the adjusted set; Digital convergence automatic adjustment, comprising: a third means for obtaining a feedback amount from the deviation amount and performing adjustment, and simultaneously performing deflection adjustment such as size on the display screen, center, linearity, and inclination on the entire screen. apparatus. 2. R (red), G (green),
A first means for setting a specific color as a reference color among the three primary colors B (blue) and first measuring a reference adjustment position at each point of the reference color; A second means for obtaining an amount of deviation from the reference adjustment position; and a third means for obtaining and adjusting the amount of feedback from the amount of deviation, and measuring and adjusting the amount of misconvergence of the three colors on the display screen. Digital convergence automatic adjustment device, wherein the digital convergence is performed simultaneously on all screens. 3. A first means for speeding up the adjustment by setting each unique feedback coefficient because the amount of change (movement) with respect to digital data at each color and each point on the display screen is different; A digital convergence automatic adjustment device comprising: a second means for automatically setting. 4. A first means having an automatic luminance follow-up function for absorbing a luminance variation of a measurement point on a display screen and a luminance variation of a back raster, and a second means having a function of removing an obstruction factor such as external light. Means for automatically adjusting digital convergence.