JPH0686334A - Convergence measuring device for color crt - Google Patents

Abstract

PURPOSE:To quickly, surely and automatically perform measuring area setting and focus adjustment in a convergence measuring preparation stage. CONSTITUTION:Two-dimensional picture signals for which patterns for measurement displayed at a color CRT 11 are image picked up by a CCD 31 are divided into plural small areas by a picture data detection circuit 46 and prescribed picture data are detected for the respective small areas. A control part 44 generates picture information binarized for the respective small areas from the picture data and discriminates whether or not convergence measurement is possible from the picture information. When the convergence measurement is impossible by the discrimination, the display position of the pattern for the measurement is moved based on a control signal generated at a movement control signal generation circuit 50 so as to make the measurement possible and when the measurement is possible, the focus of an image forming optical system 32 is automatically adjusted through a focus control circuit 34 based on the control signal generated at a focus control signal generation circuit 49 using the picture signal of the small area to which the convergence measurement is to be performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color CRT convergence measuring device for measuring the amount of misconvergence for evaluating the concentrated state of three electron beams of a color CRT.

[0002]

2. Description of the Related Art Conventionally, a color CR for displaying a predetermined white pattern for measuring convergence on a color CRT to be measured and measuring the amount of misconvergence of the color CRT to be measured using an image signal of the image of the white pattern.
A convergence measuring device of T is known.

For example, in Japanese Unexamined Patent Publication No. 2-174492, a white crosshatch pattern is displayed on a color CRT to be measured, and a partial area including at least one crosspoint in a display area of this crosshatch pattern is displayed. A convergence measuring apparatus of a color CRT that sets a vertical image and a horizontal image misconvergence amount by using image signals of respective colors of R, G, and B which are set as an image pickup region and obtained by color image pickup of a pattern image of the image pickup region. It is shown.

The convergence measuring device sets the image pickup device so as to face the image pickup area of the display screen of the color CRT to be measured, manually adjusts the focus, and then picks up a crosshatch pattern image for convergence measurement. The image signal of is read. Then, in the crosshatch pattern image included in the imaging area, a portion including vertical lines is set as a horizontal convergence measurement area, and R,
The luminance centroids of the vertical lines of G and B are calculated, and the misconvergence amount in the horizontal direction is calculated from the deviation amount of the luminance centroids of these lines.

Further, in the crosshatch pattern image included in the image pickup area, a portion including a horizontal line is set as a vertical convergence measurement area, and horizontal lines of R, G, and B colors are set in the measurement area. The luminance center of gravity is calculated, and the misconvergence amount in the vertical direction is calculated from the amount of deviation between the luminance centers of these luminance centers.

[0006]

In the convergence measurement, the image pickup device of the convergence measurement device includes at least one crosspoint in the image pickup region, and the convergence measurement region can be set in the vertical line and the horizontal line. Must be placed facing the color CRT and focus adjustment is performed on the measurement pattern image in the imaging area. The conventional color CRT convergence measurement apparatus described above does not perform setting and focus adjustment of the imaging apparatus performed as a preparation for measurement. Since it is mainly performed manually, it is difficult to simplify and speed up the measurement work.

For example, when the cross point of the cross hatch pattern is located in the peripheral part of the imaging area and the convergence measurement area cannot be set in the imaging area, the imaging device is moved so that the cross point is located in the central part of the imaging area. Therefore, the measurement preparation work becomes complicated.
Further, it is difficult to visually determine from the monitor screen whether or not the set position of the image pickup apparatus is proper, and it is also difficult to quickly set the image pickup apparatus. Especially color C
When the convergence measurement is performed at a plurality of points on the RT display screen, it takes a long time to adjust the convergence of one color CRT to be measured, which lowers the production efficiency of the CRT production line.

In consideration of high precision measurement, it is desirable that the focus adjustment of the image pickup apparatus is performed on the pattern image which is the target of the convergence measurement in the image pickup area. It is difficult to adjust the focus of the pattern image.

The present invention has been made in view of the above problems, and automatically sets the display position of the measurement pattern on the color CRT to be measured to an appropriate display position, and the pattern image of the desired convergence measurement region is obtained. Provides a color CRT convergence measurement device that can quickly measure the amount of misconvergence without moving the imaging device by automatically adjusting the focus and adopting a fine mesh measurement pattern. The purpose is to do.

[0010]

SUMMARY OF THE INVENTION According to the present invention, an image pickup means for picking up an image of a measurement pattern displayed on a color CRT to be measured and reading it as a two-dimensional image signal, and an image of the measurement pattern on the image pickup means. From the image forming optical system for forming an image, the image dividing means for dividing the two-dimensional image signal into a plurality of small areas, and whether the measurement pattern image is included in the small area based on the image signal of the small area. Image information forming means for forming image information indicating whether each small area, a small area extracting means for extracting a small area including the measurement pattern image from the image information, and a small area by the small area extracting means On the color CRT to be measured, a judgment means for judging whether or not the convergence measurement is possible from the extraction state, and when the convergence measurement is impossible, A moving means for moving the measurement pattern, and a focus position detecting means for detecting the focus position of the imaging optical system by using the image signal of the small area where the convergence measurement is performed when the convergence measurement is possible. And drive control means for driving the imaging optical system based on the detection result of the in-focus position detection means (claim 1).

Further, according to the present invention, pattern display means for displaying a measurement pattern on the color CRT to be measured, and image pickup for picking up the measurement pattern displayed on the color CRT to be measured and reading it as a two-dimensional image signal. And a focusing optical system for forming an image of the measurement pattern on the imaging means, and measuring the convergence of the color CRT to be measured based on the two-dimensional image signal. Then, the measurement pattern is
The shapes of adjacent cross points are cross hatch patterns different from each other (claim 2).

[0012]

According to the first aspect of the invention, the two-dimensional image signal obtained by imaging the measurement pattern is divided into a plurality of small areas. Further, from the image signal of the small area, image information indicating whether or not the measurement pattern image is included in the small area is formed for each small area. Then, a small area including the measurement pattern image is extracted from the image information of each small area, and it is determined whether or not convergence measurement is possible from the extraction state of the small area.When the convergence measurement is impossible, the convergence measurement is performed. The measurement pattern is moved on the color CRT to be measured so that measurement can be performed.

On the other hand, when the convergence measurement is possible or when the measurement pattern is moved to allow the convergence measurement, the focus of the imaging optical system is automatically adjusted by using the image signal of the small area in which the convergence measurement is performed. Adjusted.

According to the second aspect of the present invention, a cross hatch pattern in which adjacent cross points have different shapes is displayed on the color CRT for measurement.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic block diagram showing an embodiment of a color CRT convergence measuring apparatus according to the present invention.

In the figure, 1 is a color display for measurement, and 2 is a pattern generator for generating a predetermined measurement pattern described later. The color display 1 includes a color CRT 11 for displaying an image and the color CRT 11.
The drive control circuit 12 controls the drive of the RT 11. The video signal of the measurement pattern generated by the pattern generator 2 is input to the drive control circuit 12. The drive control circuit 12 generates a drive signal for driving the color CRT 11 from the video signal of the measurement pattern input from the pattern generator 2, and inputs this drive signal to the color CRT 11. The color CRT 11 outputs R, based on the input drive signal.
The back surface of the face plate is irradiated with three electron beams of G and B, and a predetermined phosphor is caused to emit light to display a measurement pattern on the display screen.

Further, 3 is an image pickup device for picking up an image of the measurement pattern displayed on the color CRT 11 of the color display 1, and 4 is a misconvergence amount using the image signal of the measurement pattern image picked up by the image pickup device 3. It is a device body for measuring. The image pickup apparatus 3 and the apparatus body 4 constitute a color CRT convergence measuring apparatus according to the present invention.

As the measuring pattern, various patterns can be applied, but preferably a cross hatch pattern formed by crossing vertical lines and horizontal lines or a polka dot pattern consisting of point images is used. Good. In this embodiment, the cross hatch pattern will be described as an example.

FIG. 5 is a view in which a cross hatch pattern is displayed as a measurement pattern on a color CRT. In the figure, 11 a is a display surface of the color CRT 11, 5 is a cross-hatch pattern, and 3 a is an imaging surface of the imaging device 3. The mesh size of the crosshatch pattern 5 is relative to the imaging surface 3a such that at least one vertical line or horizontal line is included in the imaging surface 3a regardless of the setting position of the imaging device 3. It is set to an appropriate size.

Returning to FIG. 1, in the image pickup device 3, a plurality of photoelectric conversion elements (hereinafter referred to as pixels) are arranged in a two-dimensional matrix, and each pixel is provided with a predetermined color filter, and an image pickup surface is provided. A color image pickup device (hereinafter referred to as CCD) 31 which photoelectrically converts the formed crosshatch pattern 5 and reads it as an electric signal, and an image forming optical system 32 which forms an image of the crosshatch pattern 5 on an image pickup surface of the CCD 31. An image pickup control circuit 33 for controlling the image pickup operation of the CCD 31, a focus control circuit 34 for controlling the focus adjustment of the image forming optical system 32 based on a focus control signal sent from the apparatus body 4, and an output from the CCD 31. And a signal processing circuit 35 for subjecting the image signal to a predetermined signal processing such as amplification and outputting it to the measuring instrument body 4.

The image pickup device 3 picks up an image of the cross hatch pattern 5 for measurement displayed on the color CRT 11 with the CCD 31, subjects the picked-up image signal to predetermined signal processing such as amplification, and then outputs it to the device body 4. To do. In addition, the device body 4
The imaging optical system 32 is driven on the basis of the focus control signal from (1) to perform the focusing operation on the image in the measurement area of the misconvergence amount. The focus control will be described later.

The apparatus body 4 includes an image signal processing circuit 41 for performing a predetermined signal processing on an image signal input from the image pickup apparatus 3 and an A / D converter 42 for converting an analog image signal into a digital image signal. An image memory 43 for storing the digital image signal, a control unit 44 for centrally controlling the convergence measurement operation, an external input / output device 45 for inputting / outputting data, and an image signal in the imaging region for a plurality of small areas. An image data detection circuit 46 that divides the image signal of a region and detects image data relating to the crosshatch pattern 5 for each small region, and a memory 4 that stores the image data.
7, a timing signal generation circuit 48 for generating a timing signal for reading the image signal input from the image pickup device 3 for each of the small areas, and a vertical or horizontal convergence measurement of the small areas. And a focus control signal generation circuit 49 for generating a focus control signal for adjusting the focus of the image of the small area and a display position of the cross hatch pattern 5 displayed on the color CRT 11. It is composed of a movement control signal generation circuit 50 that calculates the movement amount of the cross hatch pattern 5 to move and generates this signal.

FIG. 2 is a circuit diagram showing an embodiment of the image data detection circuit 46. Image data detection circuit 4
6, a two-dimensional image signal (image signal in the image pickup area A _CCD ) picked up by the image pickup device 3 is converted into 16 small areas A (i, j; i, j = 1). , 2, 3, 4)
Image data relating to the crosshatch pattern 5 is detected from the level value of the image signal included in each small area A (i, j), and the image data is output to the control unit 44. The control unit 44 generates binarized image information based on the method described later. This image information is used for each small area A
It is stored in the memory 47 corresponding to (i, j).

The binarized image information indicates whether or not the cross hatch pattern 5 is included in the small area A (i, j). For example, the area including the cross hatch pattern 5 is "1". Areas not represented by the cross hatch pattern 5 are represented by “0”. Therefore, the imaged cross hatch pattern 5 is represented by the image information as shown in FIG. 9, for example, and it is possible to determine whether or not the convergence measurement region can be set. The method of obtaining the image information and the determination as to whether or not the convergence measurement area can be set will be described later.

In FIG. 2, reference numeral 461 is a multiplexer for classifying the R, G, B color image signals input from the image signal processing circuit 41 into the small areas A (i, j).
Light receiving signals (hereinafter, referred to as pixel signals) received by each pixel of the CCD 31 are read out in time series in the raster scanning direction, and input to the multiplexer 461 through the image signal processing circuit 41. The multiplexer 461 divides, for each scanning line, the n pixel signals included in the scanning line by the horizontal division number i, and the n / i pixel signals included in each division range are respectively described below. Output to the peak hold circuits 463 to 466. It should be noted that this pixel signal division processing is performed simultaneously for the image signals of R, G, and B colors.

For example, 16 small areas A (i,
When the pixel signals are classified into j), the pixel signals G (1,1) to G (1, n) included in the first scanning line are changed to G (1,1) to G (1,1).
G (1, n / 4), G (1, n / 4 + 1) to G (1,2
n / 4), G (1,2n / 4 + 1) to G (1,3n /
4), 4 of G (1,3n / 4 + 1) to G (1, n / 4)
The pixel signals in each of the divided ranges are output to the peak hold circuits 463 to 466, respectively. Also for each of the scanning lines from the second scanning line to the m-th scanning line, the pixel signal G
(P, q; p = 2 to m, q = 1 to n) is 4 as in the above.
The pixel signals in each of the divided ranges are output to the peak hold circuits 463 to 466, respectively.

The peak hold circuits 463 to 46 are provided.
Reference numeral 6 has a peak hold circuit corresponding to each color of R, G, and B. For example, pixel signals in each divided range obtained by dividing the pixel signal of R have peak hold circuits 463 to 466 corresponding to R, respectively. Is output to. The G and B pixel signals are similarly processed.

Reference numeral 462 is a counter for generating a control signal for controlling the operation of the multiplexer 461. The timing signal generation circuit 48 is based on a signal input from the image pickup control circuit 33 of the image pickup apparatus 3 and is CC shown in FIG.
A Vs signal corresponding to a vertical synchronizing signal for controlling the driving of D31, an Hs signal corresponding to a horizontal synchronizing signal, and an S / H clock corresponding to a read timing of each pixel data are generated,
Input to the counter 462. The counter 462 is reset in synchronization with the Hs signal, and thereafter a set of control signals A. generate a select, and generate this control signal A. select to multiplexer 461
Output to.

The control signal A. update cycle of select is CC
The counter 462 counts the number of pulses of the S / H clock in a period obtained by dividing one cycle of the horizontal synchronizing signal of D31 by the number i of divisions in the horizontal direction, and the number n of pixels in one scanning line is the number of divisions in the horizontal direction. The signal state is changed every time the divided value becomes n / i divided by i. Generate a select. For example, in the example of FIG. 6, the control signal A.D. is changed by changing the signal state for each count number n / 4, n / 2, 3n / 4. Generate a select.

The peak hold circuits 463 to 466 are circuits for detecting the magnitude of the image signal included in each small area A (i, j), and the peak value of the image included in the small area A (i, j) is detected. It is something to hold. Although not shown, each peak hold circuit 463 has R, G, and
It has a peak hold circuit corresponding to each color of B.
Reference numeral 467 denotes an A / D converter 468 to be described later in order of the peak values held by the peak hold circuits 463 to 466.
It is a multiplexer that outputs to. In this case, for example, first, for the R image signal, the peak hold circuit 463
From 466 to 466, the peak hold value of each small area A (i, j) is sequentially output, and then the same processing is performed in the order of the G image signal and the B image signal to obtain each small area A (i, j).
The peak hold value of j) is output. A / D converter 4
68 converts the peak hold value output from the multiplexer 467 into a digital value.

The control unit 44 detects the vertical synchronizing signal Vs and the horizontal synchronizing signal Hs for controlling the driving of the CCD 31, and based on these both synchronizing signals Vs and Hs, the reset signal P / H. reset and control signal P / H. select and generate the peak hold circuits 463 to 46, respectively.
6 and the multiplexer 467. The reset signal P / H. reset is the peak hold circuit 4
The image signals 63 to 466 are reset. Further, the control signal P / H. “Select” is a signal that changes the state for each divided period j of the vertical synchronizing signal Vs in the vertical direction, for example, four divided periods in the example of FIG. 6, and controls the drive of the multiplexer 467. .

In the above structure, the multiplexer 46
1 is the control signal A. Based on the select, the R, G, and B pixel signals input in parallel from the image signal processing circuit 41 are horizontally divided, and the divided pixel signals are output to the corresponding peak hold circuits 463 to 466. That is, in FIG. 3, the counter 462 is reset at the falling timing T1 of the Hs signal, and the multiplexer 4
Reference numeral 61 denotes R, G, which are input from the image signal processing circuit 41.
The pixel signals of each color of B are output to the peak hold circuits 463 of the corresponding colors. After this, at timing T2, the control signal A. When select changes, the image signal processing circuit 4
1 outputs pixel signals of R, G, and B colors of respective colors to the peak hold circuits 464 of the corresponding colors, respectively. Each time the select changes, the pixel signals of R, G, and B colors input from the image signal processing circuit 41 correspond to the peak hold circuits 465 and 46 of the corresponding colors.
Change to 6 and output.

When the division of the pixel signal of the first scanning line is completed, the timing T3 of the fall of the next Hs signal is reached.
Then, the pixel signal of the second scanning line is reset by R, which is input from the image signal processing circuit 41 in the same manner as above.
The pixel signals of the colors G and B are output to the peak hold circuits 463 to 466 of the corresponding colors.

When the multiplexer 461 completes the division of the pixel signal of the m / 4th scanning line, the control unit 44 resets the reset signal P / H. select is output, and from the peak hold circuits 463 to 466 through the multiplexer 467, the small areas A (1,1) to A are sequentially output.
The peak hold value corresponding to (1, 4) is output to the A / D converter 468, and the reset signal P / H. re
set is output, and the peak hold circuits 463 to 46
The image signal in 6 is reset. After the peak hold value is converted into a digital value by the A / D converter 468,
It is input to the control unit 44.

Then, hereinafter, the (m / 4 + 1) th scanning line
The pixel signal of the m-th scanning line is also divided by the same processing as described above, and the small areas A (2,1) to A (2,2).
4), A (3,1) to A (3,4), A (4,1) to A
The peak hold value of each small area is output to the control unit 44 corresponding to (4, 4).

Next, a method of obtaining binarized image information indicating whether or not the crosshatch pattern 5 is included in the small area from the image data obtained for each small area will be described.

FIG. 7 is a diagram showing the distribution of the output of the G and B color pixels of the CCD 31 with respect to the G and B color phosphor images.

In the figure, the horizontal axis g is the output level of the color G, and the vertical axis b is the output level of the color B. Also, "G"
A group of points indicated by indicates a set of an output g _{G of a G} pixel and an output b _G of a B pixel which receive the same G phosphor image,
The group of points indicated by "B" indicates a set of the output g _B of the G pixel and the output b _B of the _B pixel which have received the same B fluorescent image.

As shown in the figure, there is a certain correlation between the output g _{G of the G} pixel and the output b _G of the B pixel which receive the same G fluorescent image. Output (g _G , b _G ) is distributed in the vicinity of the straight line Lg. Similarly, the outputs (g _B , b _B ) of a pair of pixels of G and B colors that receive the same B fluorescent image are distributed in the vicinity of the straight line Lb.

FIG. 8 models the output distribution map of FIG.
It is represented by the straight lines Lg and Lb.

The intensity of the electron beam corresponding to each color of R, G, B of the color CRT 11 is K _R , K _G , K _B , and the spectral emission of the R, G, B phosphors irradiated with unit intensity. The characteristics are R _L , G _L , and B _L , and the spectral sensitivities of the R, G, and B pixels of the CCD 13 are b _L , g _L , and b _L, and R and G when the R fluorescent image is received. , B for the respective color pixels r _R , g _R ,
b _R, R when it receives the fluorescent body image of G, G, outputs r _G of the respective colors of the pixels of B, g _G, b G, when it receives the fluorescent body image B R, G, The output of each color pixel of _{B is represented} by r _B , g _B , b
_{If it is B} , the output (r _R ,
g _R , b _R ), (r _G , g _G , b _G ), (r _B , g _B , b _B ).
Is expressed by the following equations 1 to 3.

[0042]

[Equation 1]

[0043]

[Equation 2]

[0044]

[Equation 3]

From the equations 2 and 3, the outputs g _G and b _G of the G and B color pixels for the G color fluorescent image are given by the following equations 4 and 5, and from the following equations 4 and 5: After calculating the output ratio K of the output b _G to the output g _G, intensity K _G of the electron beam becomes the following Equation 6 does not depend on the wavelength L.

[0046]

[Equation 4]

[0047]

[Equation 5]

[0048]

[Equation 6]

As described above, the intensity K _G of the electron beam is related to the brightness of the G fluorescent object image and is not related to the wavelength L, so that when the G fluorescent object images of different brightness are received. A set of outputs of G and B pixels A1 (g _G1 , b _G1 ), A2 (g
_G2 , b _G2 ) calculated output ratio b _G1 /
g _G1 and b _G2 / g _G2 are equal to each other according to the above equation 6,
It can be seen that points 1 and A2 are distributed on Lg as shown in FIG. Similarly, a pair of outputs (b _B , g _B ) of G and B pixels when receiving a B fluorescent image having different brightness are:
It is distributed on Lb.

When the electron beam intensities K _G and K _B are increased, the G and B phosphor images become brighter, so the outputs (g _G and b _G ) are distributed on the right end side on the line Lg, The outputs (b _B , g _B ) are distributed on the upper end side on the line Lb.

As shown in FIGS. 7 and 8, for example, an output corresponding to the spectral characteristic is generated in the G pixel which receives the B fluorescent image, so that the B color is added to the G color image signal. It contains the signal that received the optical image. Similarly, when an R, B fluorescent image is received, an output corresponding to the spectral characteristic is generated in the G pixel, so that an R, G, B image signal of G color is generated.
That is, the signal received from each of the fluorescent images is included. This also applies to the R and B color image signals.

Since the G color image signal includes not only the image signal for receiving the G fluorescent image but also the image signal for receiving the R and B fluorescent images, the small area A ( Even if it can be detected from the peak hold value of the G color image signal in i, j) that the crosshatch pattern 5 is included, whether or not the crosshatch pattern 5 is due to the G color fluorescent image. Cannot be determined.

The binarized image information is information for determining whether or not all the R, G, and B crosshatch patterns 5 are included in the corresponding small area. Therefore, the binarized image information is generated by performing the following two types of discrimination using the peak hold values of the R, G, and B image signals for each small area.

Determination of whether or not the crosshatch pattern 5 exists in the small area.

When the crosshatch pattern 5 exists in the small area, it is determined whether or not the crosshatch pattern 5 of all colors of R, G and B is included.

In the above discrimination, for example, when there is no crosshatch pattern 5 of any color (hereinafter, this state is referred to as a dark state), the pixel output of each color of the CCD 13 is used as a threshold, and the peak hold value of each small area is determined. It is performed by comparing with this threshold value. That is, each small area A
If the peak hold value of (i, j) is less than or equal to the threshold value, the small area A (i, j) is determined to be in a dark state, and the peak hold value of each small area A (i, j) is larger than the threshold value. For example, it is determined that the small area A (i, j) includes the crosshatch pattern 5 of any color.

Next, FIG. 8 for explaining the above discrimination.
Now, if it is assumed that the image signal of the color G of a certain small area A (i, j) is g _G1 and the image signal of the color B is b _B1 , then within the small area A (i, j) If there is a fluorescent image of B color, the image signal g _B1 is included in the image signal of G color. Therefore, this image signal g _B1 and the image signal g _G1
Comparing with, we have g _G1 >> g _B1.
It is determined that there is a high possibility that a G color phosphor image exists in (i, j).

Similarly, if the small area A (i, j) has G
If there is a fluorescent image of color B, the image signal b _G1 is included in the image signal of color B. Therefore, by comparing this image signal b _G1 and the image signal b _B1, because a b _B1 »b _G1, the small area A (i, j) fluorescent body image color B is in the presence It is highly likely that

Next, assuming that the G color image signal of the small area A (i, j) is g _G1 and the B color image signal is b _B1 , the image signal in the G color image signal is 'If is included, the image signal g _B' g _B from the comparison between the image signal g _G1 and, from the g _G1 »g _B ', the small areas a (i,
It is judged that there is a high possibility that a G color fluorescent image exists in j). In this case, as shown in FIG. 8, the image signal obtained by receiving the G color fluorescent image contained in the B color image signal is b _G1 . Therefore, the small area A (i, j) In B
It cannot be distinguished that there is a fluorescent image of the color.

Then, the same discrimination processing as described above is performed for the R color image signal, and as a result, it is highly likely that, for example, a G color fluorescent image exists for all color image signals. If determined, the small area A (i, j)
There is only a G color fluorescent image inside, and other R and B
It is assumed that there is no fluorescent image of the color.

As described above, when the cross hatch pattern 5 exists in the small area A (i, j), R,
It is determined whether or not the cross hatch pattern 5 of each color of G and B exists.

FIG. 9 shows an imaged crosshatch pattern 5
It is the figure which represented with the image information. FIG. 7A shows a case where the cross point of the crosshatch pattern 5 is not in a small area adjacent to the screen boundary of the image pickup area A _CCD , and FIG.
_The case is shown in a small area adjacent to the _CCD screen boundary. In the imaging area A _CCD , “0” and “1” indicate image information, “0” indicates a small area that does not include the crosshatch pattern 5, and “1” indicates a small area that includes the crosshatch pattern 5. There is.

Since the cross hatch pattern 5 is included in the small area of the image information "1", a measurement area for convergence measurement (hereinafter referred to as a convergence measurement area) can be set in the small area. The horizontal convergence measurement area can be set to a small area that includes vertical lines (hereinafter referred to as vertical line small area), that is, a small area that is not in contact with the small area of image information "1" in the horizontal direction. The vertical convergence measurement area may be set to a small area including a horizontal line (hereinafter referred to as a horizontal line small area), that is, a small area that is not in contact with the small area of the image information “1” in the vertical direction. it can.

In FIG. 9A, the small area A (1,
2), A (3,2), A (4,2) can be vertical line small areas, and small areas A (2,1), A (2,3),
A (2,4) can be set as a horizontal line small area. Therefore, the small areas A (1,2), A (3,2), A
Select either (4, 2) as the vertical line small area,
The lateral misconvergence amount is measured using the image signal of the convergence measurement region set in the selected small region.

For example, when the small area A (1,2) is selected as a vertical line small area, the focus of the imaging optical system 32 is adjusted using the image signal of the small area A (1,2). The focus control signal generation circuit 49 uses the image signal of the small area A (1, 2) to generate a control signal for instructing the moving direction of the focus lens group of the imaging optical system 32, and the control signal is used for the image pickup apparatus. 3 to the focus control circuit 34. The focus control circuit 34 moves the focus lens group of the imaging optical system 32 in a predetermined direction at a predetermined speed based on this control signal. The image signals picked up while moving the focus lens group are sequentially stored in the image memory 47, while the image signals included in the small area A (1, 2) are generated from the image memory 47 by the focus control signal. It is sent to the circuit 49. The focus control signal generation circuit 49 uses the newly input image signal of the small area A (1, 2) to renewally generate the control signal of the focus lens group by a so-called hill-climbing method, and the focus control signal generation circuit 49 Focus control circuit 34
Send to. Then, when the control signal from the focus control signal generation circuit 49 is stopped, the movement of the focus lens group is stopped, and the imaging optical system 32 is moved to the small area A (1,2).
The focus is adjusted to the crosshatch pattern 5 of.

Then, after that, the small areas A (1, 2)
The vertical misconvergence amount is calculated using the image signal of the horizontal line in the convergence measurement region.
The misconvergence amount in the vertical direction is calculated by calculating the luminance centroids r _DY , g _DY , and b _DY for the horizontal lines of each color of R, G, and B that form the horizontal line, and further calculating the amount of shift between these luminance centroids, Δd _RGY (= r _DY −g _DY ), Δd
_BGY (= b _DY −g _DY ) is the imaging magnification β of the imaging optical system 32, and the deviation amount ΔD _RGY (= Δd _RGY / β), ΔD _BGY (= Δd _BGY / β) of the luminance center of gravity on the display screen of the color CRT 11.
Calculated by converting to.

The calculation of the vertical misconvergence amount is performed in the same procedure as described above. For example, when the small area A (2,1) is selected as the measurement area, focus adjustment is performed on the cross hatch pattern 5 of the small area A (2,1), and the convergence of the small area A (2,1) is performed. The amount of misconvergence in the horizontal direction ΔD _RGX (= Δd _RGX / β), ΔD using the image signal of the vertical line in the measurement area
_BGX (= Δd _BGX / β) is calculated.

On the other hand, in FIG. 9B, the small area A
(2,1), A (3,1), A (4,1) can be defined as vertical line small areas, and small areas A (1,2), A (1,
3) and A (1,4) can be used as horizontal line small areas, but these small areas are all adjacent to the screen boundary of the imaging area A _CCD , and vertical lines or horizontal lines are each small areas. Within the area of the image area A _CCD near the screen boundary,
It may be possible that the convergence measurement area cannot be set in the small area. Therefore, crosshatch pattern 5
If the cross point of is included in the small area A (i, j) adjacent to the image area A _CCD screen boundary, it is determined that the convergence measurement area cannot be set, and the convergence measurement area can be set reliably. After that, that is, the cross point of the cross hatch pattern 5 is not in the small area A (i, j) adjacent to the screen boundary of the imaging area A _CCD , the convergence measurement area is set.

For example, a small area including a cross point is A
In the case of (1, 1) (see FIG. 9B), the movement control signal generation circuit 50 causes the display screen of the CRT 1 to move the small area including the cross point to, for example, the small area A (3, 3). The movement amount of the cross hatch pattern 5 in
The calculation result is sent to the pattern generator 2 as a movement control signal. Based on this movement control signal, the pattern generator 2 produces a color CRT for the crosshatch pattern 5.
The display position of 11 on the display surface 11a is moved toward the screen by a predetermined amount in the lower right direction. As a result, the small area including the cross point moves from A (1,1) to A (3,3). For example, the small area A (3,4) can be set as the horizontal line small area, and the small area A ( 4, 3) can be set as vertical line small areas. And these small areas A
The amount of misconvergence in the vertical and horizontal directions is measured using (1,4) and A (4,3) as described above.

FIG. 10 is a diagram showing another example in which the imaged cross hatch pattern 5 is shown by image information. 9A and 9B show the case where the cross point of the cross hatch pattern 5 is not in the small area adjacent to the screen boundary of the image pickup area A _CCD . In FIG. 7A, the small area A (1,
3), A (3,3), A (4,3) can be used as vertical line small areas, and in FIG. 7B, small areas A (2,1),
A (2,2) and A (2,4) can be set as horizontal line small areas.

Further, FIGS. 7C and 7D show the case where the cross point of the cross hatch pattern 5 is in a small area adjacent to the screen boundary of the image pickup area A _CCD . In any of these cases, it is determined that the convergence measurement area cannot be set. Therefore, in the case of FIG. 7C, for example, the display position of the crosshatch pattern 5 is moved rightward by the amount of one or two small areas, and in the case of FIG. The display position of is moved downward by an amount corresponding to one or two small areas so that the small area including the cross point is not present in the small area adjacent to the screen boundary of the imaging area A _CCD .

Next, a control operation for setting a vertical line small area and a horizontal line small area for convergence measurement from image information will be briefly described with reference to FIGS. 11 to 13.

Here, for convenience of explanation, a case where the image pickup area A _CCD shown in FIG. 9 is divided into 16 areas will be described as an example. Further, a case where the crosshatch pattern 5 in the imaging area A _CCD satisfies the following conditions 1 to 5 will be described.

Two or more vertical lines and horizontal lines of the crosshatch pattern 5 are not included in the image pickup area A _CCD .

The horizontal dimension of the small area A (i, j) is larger than the width of the vertical line, and the vertical dimension of the small area A (i, j) is larger than the width of the horizontal line.

[0076] Vertical lines or horizontal lines in the imaging area A _CCD is traversing completely the imaging area A _CCD.

FIG. 11 and FIG. 12 are main flows of control for setting a vertical line small area and a horizontal line small area for convergence measurement from image information.

When the image information of each small area A (i, j) is obtained for the image signal of the image pickup area A _CCD , first, the image information of the small area A (1,1) at the upper left corner is "0". Whether or not it is determined (# 1). If the image information of the small area A (1,1) is “0”, the process proceeds to # 3 to detect the vertical line small area. If the image information of the small area A (1,1) is “1”, the process proceeds to # 53 to # 67 described later.

When the process proceeds to # 3, in steps # 3 to # 11, the small area A (1, j) (j = 2 to 4) is moved to the right while determining whether the image information is "0". Then, the area including the crosshatch pattern 5 is detected for the small areas A (1,2) to A (1,4) in the first row. When the small area A (1, j) having the image information of "1" is detected by this detection processing (NO in # 7), the small area A (1, j) is detected.
Is set to the vertical line small area (# 9), and the process proceeds to # 13. On the other hand, when the small area A (1, j) having the image information of “1” is not detected in the detection processing (NO in # 5),
Since the vertical lines are not included in the imaging area A in _CCD, a vertical line sub-region is determined to be the imaging area A _CCD outside (# 1
1), shift to # 13.

At step # 13, the horizontal line small area is detected in the same manner as the vertical line small area detecting process described above. That is, after the initial value of the small area to be detected is set to A (1,1) in # 13, the small area is determined while determining whether the image information is “0” in steps # 15 to # 23. A (i, 1) (i = 2-4) is moved downward to
A region including the crosshatch pattern 5 is detected for the small regions A (2,1) to A (4,1) in the column. When the small area A (i, 1) having the image information of "1" is detected in this detection process (NO in # 19), the small area A (i, 1) is detected.
Is set to the horizontal line small area (# 21), and the process proceeds to # 25. On the other hand, when the small area A (i, 1) having the image information of "1" is not detected in the detection processing (N in # 17).
O), because the horizontal line is not included in the imaging area A in _CCD, the horizontal line the small region is determined to be the imaging area A _CCD outside (# 23), the process returns to # 25. In addition, N in # 23
In the case of O, the vertical line small area and the horizontal line small area are not detected, which means that there is no crosshatch pattern 5 in the imaging area A _{CC D.}

Then, it is determined whether or not the convergence measurement area can be set from the detected vertical line small area and horizontal line small area (# 25). In this determination, the detected vertical line small area or horizontal line small area is the imaging area A.
If it is adjacent to the _CCD screen boundary, or if the vertical line small area or horizontal line small area is outside the imaging area A _CCD, it is determined that the convergence measurement area cannot be set. In other cases, the convergence measurement area is set. It is determined to be possible.

If it is determined in # 25 that the convergence measurement area can be set (YES in # 25), step # 2
Then, the process proceeds to 6 and the above-described convergence measurement process is performed. That is, the focus adjustment is performed using the image signal of the small area A (1, j) detected as the vertical line small area, and the image signal of the convergence measurement area set in the small area A (1, j) is displayed. Use to make lateral convergence measurements. Further, the focus adjustment is performed using the image signal of the small area A (i, 1) detected as the horizontal line small area, and the image signal of the convergence measurement area set in the small area A (i, 1) is displayed. Use to perform vertical convergence measurements.

When it is determined in # 25 that the convergence measurement area cannot be set, the process proceeds to # 27 and the color CRT1
The display position of the cross hatch pattern 5 displayed in 1 is moved.

FIG. 13 is a flow chart for controlling the display position of the cross hatch pattern 5.

First, it is judged whether or not the vertical line small area is in the image pickup area A _CCD (# 31). When it is in the image pickup area A _CCD , the small area A further detected as the vertical line small area is detected. The position of (1, j) is confirmed (# 33). And
When the small area A (1, j) detected as the vertical line small area is the left end of the imaging area A _CCD (# 33, left end), the crosshatch pattern 5 is the small area A to the right in the imaging area A _CCD . The amount of movement of the display position of the crosshatch pattern 5 on the display screen of the color CRT 11 is set so as to move by an amount corresponding to twice the lateral dimension of (i, j) (# 3
5), a small area A (1,
When j) is the right edge of the imaging area A _CCD (# 33, right edge), the crosshatch pattern 5 corresponds to twice the lateral dimension of the small area A (i, j) in the left direction in the imaging area A _CCD . The movement amount of the display position of the crosshatch pattern 5 on the display screen of the CRT 1 is set so as to move by the amount (# 3
5).

On the other hand, when the vertical line small area is not in the image pickup area A _CCD at # 31, the crosshatch pattern 5 corresponds to four times the lateral dimension of the small area A (i, j) in the right or left direction. The movement amount of the display position of the crosshatch pattern 5 on the display screen of the color CRT 11 is set so as to move by the amount (# 39).

Subsequently, the small area of the horizontal line is the imaging area A _CCD.
If it is within the imaging area A _CCD , the position of the small area A (i, 1) detected as a horizontal line small area is further confirmed (# 43). . Then, the small area A (i, i, detected as the horizontal line small area
When 1) is the upper end of the image pickup area A _CCD (# 43, upper end), the crosshatch pattern 5 corresponds to twice the vertical dimension of the small area A (i, j) downward in the image pickup area A _CCD . The movement amount of the display position of the cross hatch pattern 5 on the display screen of the color CRT 11 is set so as to move by the amount (# 45), and the small area A detected as the horizontal line small area is set.
If (i, 1) is the lower edge of the imaging area A _CCD (# 45,
Bottom edge), the crosshatch pattern 5 on the display screen of the color CRT 11 so that the crosshatch pattern 5 moves upward in the imaging area A _CCD by an amount equivalent to twice the vertical dimension of the small area A (i, j). The movement amount of the display position of is set (# 47).

On the other hand, if the horizontal line small area is not in the image pickup area A _CCD at # 41, the crosshatch pattern 5 corresponds to four times the vertical dimension of the small area A (i, j) in the upward or downward direction. The movement amount of the display position of the crosshatch pattern 5 on the display screen of the color CRT 11 is set so as to move by the amount (# 49).

Subsequently, the set movement amount is output to the pattern generator 2 (# 51), and the display position of the crosshatch pattern 5 on the display screen of the color CRT 11 is moved in a predetermined direction by a predetermined amount. After that, the crosshatch pattern 5 is imaged again, and the above-described processing of # 1 to # 51 is performed on the image information obtained for this imaging signal, and when the convergence measurement area can be set (# 25 YES), the process moves to step # 26 and the convergence measurement process is performed.

Returning to FIG. 11, the small area A (1,
If the image information of 1) is "1" (NO in # 1),
Move to # 53 shown in 2 and the small area A (4, 1) in the lower left corner
It is determined whether or not the image information of is 0. Small area A
If the image information of (4, 1) is "0" (YE in # 53)
S), since the vertical lines of the crosshatch pattern 5 are not included in the small area A (i, 1) (i = 1 to 4) in the first column, the small area A (1,1) is set to the horizontal line. After setting the small area (# 55), the same processing as that of # 3 to # 11 is performed and the vertical line small area of the small area A (4, j) (j = 2 to 4) of the fourth row is set. Detection (# 57), # 25
Move to.

If the image information of the small area A (4,1) in the lower left corner is "1" (NO in # 53), the image information of the small area A (1,4) in the upper right corner is "0". It is determined whether or not it is "(# 59). If the image information of the small area A (1,4) is "0" (YES in # 59), the crosshatch pattern 5 is applied to the small area A (i, 1) (i = 1 to 4) in the first column.
Vertical lines are included, the small area A (1,1) is set as a vertical line small area (# 61), and then # 15 to # 2.
By performing the same processing as in step 3, the small area A (i,
4) The horizontal line small area is detected for (i = 2 to 4) (# 63), and the process proceeds to # 25.

If the image information of the small area A (1, 4) at the upper right corner is "1" in # 59 (NO in # 59), the small area A is displayed.
(1,1) is the area including the cross point,
A horizontal line and a vertical line of the crosshatch pattern 5 are respectively provided in the small areas A (1, j) (j = 1 to 4) in the row and the small areas A (i, 1) (i = 1 to 4) in the first column. Since the lines are included, for example, the small area A (4,1) and the small area A (1,4)
Are set as the vertical line small area and the horizontal line small area (# 65, # 67), and the process proceeds to # 25.

After the processing of # 53 to # 67,
When migrating to 25, or the detected vertical line small area or horizontal line the small regions are adjacent to the screen boundary of the imaging region A _CCD, or from the imaging region A _CCD outside and # 25,
It is determined that the convergence measurement area cannot be set. Therefore, the process moves to # 31 to # 51, and the display position of the cross hatch pattern 5 on the display surface 11a of the color CRT 11 is moved so that the convergence measurement area can be set.

By the way, in the above embodiment, the movement amount of the display position of the cross hatch pattern 5 is determined by the small area A (i, j).
However, the crosshatch pattern 5 displayed on the display surface 11a of the color CRT 11 is set based on the horizontal dimension and the vertical dimension (see steps # 35, # 37, # 39, # 45, # 47, and # 49). The horizontal pitch P1 and the vertical pitch P2 (see FIG. 5) can be set as a reference.

FIG. 14 is a flowchart of the first embodiment of the display position control of the crosshatch pattern based on the vertical and horizontal pitches of the crosshatch pattern. The processing of steps # 25 to # 51 in FIGS. 11 and 13 is performed. Is equivalent to.

In this embodiment, when the vertical line small area or the horizontal line small area is not included in the image pickup area A _CCD , the display position of the cross hatch pattern 5 on the display surface 11a of the color CRT 11 is set to P1 in the horizontal direction. The vertical line small area or the horizontal line small area is included in the image pickup area A _CCD by moving by 1/2 unit or by P2 / 2 unit in the vertical direction.

Further, in consideration of high-speed processing of measurement, in order to ensure that the vertical line small area or the horizontal line small area is included in the image pickup area A _{CCD by one} movement of the display position of the crosshatch pattern 5. And the display surface 11 of the color CRT 11
The crosshatch pattern 5 displayed in a is the image pickup device 3
The horizontal size Q1 and the vertical size Q2 of the image pickup screen 3a of FIG.
P1 ≦ (1.5-2 / i) × Q1 P2 ≦ (1.55-2 / i) × Q2 i: The number of divisions in the vertical direction of the imaging screen 3a (see FIG. 6) is satisfied. The mesh size is set to ON.

In this embodiment, as shown in FIG. 6, i = 4
Is set to (1.5-2 / i) = 1,
The mesh size of the crosshatch pattern 5 is P1 ≦ Q
1 and P2 ≦ Q2 are set to be satisfied. In addition, the number of divisions i is made larger, and (1.5-2 / i) ≈
When it becomes 1.5, the mesh size of the cross hatch pattern 5 can be set to satisfy P1 ≦ 1.5 × Q1 and P2 ≦ 1.5 × Q2.

In FIG. 14, steps # 21 and # 23.
Alternatively, when the process moves from step # 57, # 63, # 67 to step # 70 in FIG. 12, the vertical line small area becomes the imaging area A.
_If the vertical line small area is in the imaging area A _CCD (YES in # 70), it is further determined whether the horizontal line small area is in the imaging area A _CCD . Yes (# 72). If the horizontal line small area is within the imaging area A _CCD (YES in # 72), the vertical and horizontal convergence measurements are performed using the image signals of the crosshatch pattern 5 of the vertical line small area and the horizontal line small area. Do (# 7
4).

Imaging area A If there is no small horizontal line area in _CCD (NO in # 72), display surface 11 of color CRT 11
The movement information of the display position of the crosshatch pattern 5 in a is set to the content for moving P2 / 2 upward (or downward) (# 76), and this movement information is sent to the pattern generator 2 (# 84). ), Return to # 1.

The pattern generator 2 delays (or advances) the phase of the vertical synchronizing signal by an amount corresponding to P2 / 2 based on the input movement information, and displays the cross hatch pattern 5 on the display surface 11a of the color CRT 11. Is moved upward (or downward) by P2 / 2. As a result, in the second measurement operation, the vertical line small region and the horizontal line small region are included in the imaging region A _CCD , and it is possible to shift from # 72 to # 74 and perform the convergence measurement.

If there is no vertical line small area in the image pickup area A _CCD (NO in # 70), it is further determined whether or not there is a horizontal line small area in the image pickup area A _CCD (# 78). Area A If there is a small horizontal line area in _CCD (YE in # 78
S), the movement information of the display position of the cross hatch pattern 5 on the display surface 11a of the color CRT 11 is set to the content of moving P1 / 2 to the left (or right) (# 8).
0), if there is no horizontal line small area in the imaging area A _CCD (NO in # 78), the movement information of the display position of the crosshatch pattern 5 on the display surface 11a of the color CRT 11 is set to P1 in the left direction (or right direction). Set to the content to move P / 2/2 in the up / down direction (or in the down direction) (# 8
2) Then, the movement information is sent to the pattern generator 2 (# 84) and the process returns to # 1.

The pattern generator 2 delays (or advances) the phase of the horizontal synchronizing signal by an amount corresponding to P1 / 2 based on the input movement information, or the vertical and horizontal synchronizing signals are respectively P2 / 2 and P2 / 2. The display position of the crosshatch pattern 5 on the display surface 11a of the color CRT 11 is delayed (or advanced) by an amount corresponding to P1 / 2, and the display position of the crosshatch pattern 5 is moved upward (or downward) by P2 / 2 or obliquely downward left (or obliquely). P (= √ (P1 ² + P
Move 2 ² ) / 2. As a result, in the second measurement operation, the vertical line small region and the horizontal line small region are included in the imaging region A _CCD , and it is possible to shift from # 72 to # 74 and perform the convergence measurement.

In FIG. 14, step # 76 is changed to the same processing as step # 82, and
When Step # 80 and Step # 82 are removed and both the vertical line small area and the horizontal line small area are not included in the imaging area A _{CC D} , the display surface 11 of the color CRT 11 is always displayed.
The display position of the crosshatch pattern 5 in a is set to P (= √ (P1 ² + P) in the diagonally lower left direction (or diagonally lower right direction).
It is also possible to move by 2 ² ) / 2 so that both the vertical line small area and the horizontal line small area are included in the imaging area A _CCD after the pattern is moved.

FIG. 15 is a flow chart of the second embodiment of the display position control of the cross hatch pattern based on the vertical and horizontal pitches of the cross hatch pattern, which corresponds to the processing of steps # 25 to # 51 in FIG. It is a thing.

In the first embodiment, after moving the display position of the crosshatch pattern 5 so that the vertical line small area and the horizontal line small area are included in the image pickup area A _CCD , convergence measurement in both vertical and horizontal directions is performed. However, in the second embodiment, when the image pickup area A _CCD includes a small area of either a vertical line small area or a horizontal line small area, the small area in the vertical or horizontal direction is After the convergence measurement is performed, the display position of the crosshatch pattern 5 is moved to perform the convergence measurement in the unmeasured direction.

In FIG. 15, steps # 21 and # 23.
Alternatively, when the process moves from step # 57, # 63, # 67 to step # 90 in FIG. 12, it is determined whether or not there is a vertical line small area in the imaging area A _CCD , and the vertical line small area is included in the imaging area A _CCD . If there is (YES in # 90), it is determined whether or not the flag F1 is set to "1"(# 9).
2). This flag F1 is a flag for determining whether or not the lateral convergence measurement is completed.
When it is set to "1", it indicates that the lateral convergence measurement is completed, and when it is reset to "0", it indicates that the lateral convergence measurement is not completed.

When the flag F1 is set to "1" (YES in # 92), the convergence measurement in the horizontal direction is completed, so the routine jumps to # 98 and the flag F1 is reset to "0". (NO in # 92), the horizontal convergence measurement is performed using the image signal of the crosshatch pattern 5 in the vertical line small area (# 9).
4), set the flag F1 to "1"(# 96), #
Move to 98.

Then, it is determined whether or not the flag F2 is set to "1"(# 98). This flag F2
Is a flag for determining whether or not the vertical direction convergence measurement has been completed. When set to "1", it indicates that the vertical direction convergence measurement has been completed, and is set to "0". When reset, it indicates that the vertical convergence measurement is not complete. When the flag F2 is set to "1" (YE in # 98)
S), since the convergence measurement in both vertical and horizontal directions has been completed, the process moves to # 104, and the flags F1 and F2 are set to "0".
To reset the process to end.

When the flag F2 is reset to "0" (NO in # 98), it is further determined whether or not there is a small horizontal line area in the image pickup area A _CCD (# 100). If the horizontal line small area is in the imaging area A _CCD (Y in # 100)
S), vertical direction convergence measurement is performed using the image signal of the cross hatch pattern 5 of the horizontal line small area (# 102), the flags F1 and F2 are reset to "0", and the process is terminated (# 104). ).

Imaging area A If there is no small horizontal line area in _CCD (NO in # 100), display surface 1 of color CRT 11
The movement information of the display position of the crosshatch pattern 5 in 1a is set to the content to move P2 / 2 upward (or downward) (# 106), and this movement information is sent to the pattern generator 2 (# 118). ), Return to # 1.

The pattern generator 2 is a color CRT.
The display position of the crosshatch pattern 5 on the display surface 11a of 11 is moved upward (or downward) by P2 / 2. As a result, in the second measurement operation, the imaging area A
_The horizontal line small area is included in the _CCD . # 100 to # 10
The process moves to the process of No. 4, and the vertical convergence measurement is performed.

If there is no vertical line small area in the image pickup area A _CCD (NO in # 90), it is further judged whether or not there is a horizontal line small area in the image pickup area A _CCD (# 108). Area A If there is a horizontal line small area in the _CCD (YES in # 108), vertical direction convergence measurement is performed using the image signal of the cross hatch pattern 5 of the horizontal line small area (# 110), and the flag F2 is set. It is set to "1"(# 112). Next, the display surface 11 of the color CRT 11
The movement information of the display position of the cross hatch pattern 5 in a is set to the content of moving P1 / 2 to the left (or the right) (# 114), and this movement information is sent to the pattern generator 2 (# 118). ), Return to # 1.

The pattern generator 2 is a color CRT.
The display position of the crosshatch pattern 5 on the display surface 11a of 11 is moved to the left (or right) by P1 / 2, so that in the second measurement operation, the imaging area A _CCD
A vertical line small area is included in the area, and the process shifts to # 90 to # 96 to perform vertical convergence measurement.

Imaging area A If there is no small horizontal line area in _CCD (NO in # 108), display surface 1 of color CRT 11
The movement information of the display position of the cross hatch pattern 5 in 1a is set to the content of moving P1 / 2 to the left (or the right) and P2 / 2 to the up (or the down) (#
116), and the movement information is transmitted to the pattern generator 2
(# 118) and returns to # 1.

The pattern generator 2 is a color CRT.
The display position of the cross hatch pattern 5 on the display surface 11a of 11 is P2 / 2 in the upward direction (or the downward direction) or P (= √ (P
1 ² + P2 ² ) / 2, so that in the second measurement operation, the vertical line small area and the horizontal line small area are included in the imaging area A _CCD , and the process proceeds from # 90 to # 104. Convergence measurement is performed in both vertical and horizontal directions.

FIG. 16 is a flowchart of the third embodiment of the display position control of the cross hatch pattern based on the vertical and horizontal pitches of the cross hatch pattern.

FIG. 16 shows a step # 1 in FIG.
06 to step # 10 having the same contents as step # 116
6 ', step # 114 and step # 116
Is removed.

In the third embodiment, when neither the vertical line small area nor the horizontal line small area is included in the image pickup area A _CCD , the display position of the crosshatch pattern 5 on the display surface 11a of the color CRT 11 is always slanted. Move by P (= √ (P1 ² + P2 ² ) / 2 in the lower left direction (or diagonally lower right direction), and after the pattern is moved, the imaging area A _CCD must include both vertical line small areas and horizontal line small areas. It was designed to be

In the third embodiment, since the movement information of the crosshatch pattern 5 is always constant, the movement information contents are set in the pattern generator 2 in advance, and # 10
6 A little from the image pickup apparatus main body 4 to the pattern generator 2
Alternatively, only the control signal for instructing the movement may be transmitted. In this way, it is not necessary to set the movement information according to the movement direction of the crosshatch pattern 5, so that the processing becomes simple and the convergence measurement can be performed at a higher speed.

In addition, in the first and second embodiments, the horizontal pattern movement amount (P1 / 2) and the vertical pattern movement amount (P2 / 2) are preset in the pattern generator 2. , Steps # 76, # 80,
In # 82 and steps # 106, # 114, and # 116, only the control signal for instructing the moving direction to the pattern generator 2 may be sent from the image pickup apparatus main body 4.

Further, in the above-mentioned method of moving the display position of the cross hatch pattern 5, the display position of the cross hatch pattern 5 is changed by a predetermined moving amount according to the state of the cross hatch pattern 5 included in the image pickup area A _{CC D.} Although it is moved, the drive of the pattern generator 2 may be directly controlled by the image pickup apparatus main body 4 to move the display position of the crosshatch pattern 5 directly from the image pickup apparatus main body 4.

That is, when the vertical line small area and the horizontal line small area are not included in the image pickup area A _CCD from the image picked up by the image pickup apparatus 3, a control signal for instructing movement from the image pickup apparatus main body 4 in a predetermined direction. Is sent to the pattern generator 2 to start moving the display position of the crosshatch pattern 5, and whether the vertical line small area and the horizontal line small area are included in the image pickup area A _CCD from the sequentially captured image signals. Determine whether or not. Then, the imaging area A
_{When it is determined that the CCD} includes the vertical line small area and the horizontal line small area, and it is possible to measure the convergence in the vertical direction and the horizontal direction, a stop signal is sent from the image pickup apparatus main body 4 to the pattern generator 2 and the hatch pattern 5 Stop moving. By doing so, it is possible to move the display position of the crosshatch pattern 5 so that the vertical line small area and the horizontal line small area are surely included in the imaging area A _CCD , and at the same time, move the crosshatch pattern 5. Since the amount can be controlled to a necessary minimum, the convergence measurement process can be speeded up.

FIG. 17 is a schematic diagram showing another embodiment of the color CRT convergence measuring apparatus according to the present invention.

In the drawing, in FIG. 1, the focus control circuit 34 is connected to the focus control signal generating circuit 49 and the image forming optical system 32 is formed.
In addition to providing the signal line S1 for transmitting the position information of No. 1 and the signal line S2 for transmitting the position information of the image forming optical system 32 from the focus control signal generating circuit 49 to the control negative 44.

In this embodiment, the position information of the image forming optical system 32 is detected during focus control, and this position information is sent from the focus control circuit 34 to the focus control signal generation circuit 49. The focus control signal generation circuit 49 calculates the position of the imaging optical system 32 from the input position information, and sends the calculation result to the control unit 44. In focus control, the control unit 44 controls the small area A (i, i,
The focus lens group of the imaging optical system 32 is moved in one direction while the peak value of the image signal of j) is stored in the memory 47 in association with the position of the imaging optical system 32. The peak value of the image signal corresponding to the position of the imaging optical system 32 detected during the movement of the focus lens group includes the focus position for each small area A (i, j) in which the crosshatch pattern 5 exists. Has been.

When the small area A (i, j) to be subjected to convergence measurement is selected, the control unit 44 sets the in-focus position corresponding to the small area A (i, j) from the memory 47, and sets the in-focus position. The position information is sent to the focus control signal generation circuit 49. The focus control signal generation circuit 49 generates a focus control signal from the in-focus position information and sends it to the focus control circuit 34. The focus control circuit 34 moves the focus lens group of the imaging optical system 32 to the in-focus position based on this focus control signal.

In this embodiment, since the imaging optical system 32 is moved directly to the in-focus position, there is an advantage that the focus control can be performed more quickly than the hill climbing method of the previous embodiment. Further, since the in-focus position is detected corresponding to the vertical line or horizontal line of the convergence measurement target, for example, when there is a shift in the in-focus position between the vertical line and the horizontal line, suitable focus control for each line is performed. Can be done. on the other hand,
When there is little shift in the focus position between the vertical line and the horizontal line and it is possible to set the average focus position in terms of convergence measurement accuracy, the focus of the imaging optical system 32 is set to the average focus position. It is also possible to simplify the focus control by controlling the.

Further, if the position of the cross hatch pattern 5 is not proper, and if there is an image of vertical lines or horizontal lines, it is possible to detect the tilted state of the display surface of the color CRT 11 using both lines. As a result, the focus position in the convergence measurement region after controlling the position of the crosshatch pattern 5 is estimated, and the focus control is performed, whereby the processing speed of the focus control can be improved.

In the above embodiment, when the convergence measurement area cannot be set due to the positional relationship of the crosshatch pattern 5 with respect to the image pickup screen, the color CRT 11 is used.
Although the display position of the crosshatch pattern 5 on the display surface 11a of FIG. 6 is moved so that the convergence measurement region can be set, if the mesh of the crosshatch pattern 5 is made fine, the convergence measurement region can always be set. . In this case, the configuration for moving the crosshatch pattern 5 as described above is unnecessary.

If the fine mesh crosshatch pattern 5 is adopted, the amount of misconvergence with respect to the pitch of the crosspoints of the measurement pattern becomes relatively large. For example, as shown in FIG. 18, the crosshatch pattern of R color is shown. Whether the vertical line of the cross hatch pattern 5 of the color G that should match the vertical line L1 of 5 is L2,
It may not be possible to determine if it is 3. In order to avoid such a state, it is preferable to use the crosshatch pattern 5 having different crosspoint shapes.

FIG. 19 shows an example of the crosshatch pattern 5 having different crosspoint shapes. In the crosshatch pattern 5 shown in the figure, the crosspoint where the vertical line and the horizontal line intersect is two vertical and horizontal lines of two vertical lines and two horizontal lines to the crosspoint. Only the two are connected to the cross point, and the remaining two vertical and horizontal lines are configured so that their tips are not connected to the cross point.

That is, for horizontal lines, from the top, and for vertical lines from the left, 1, respectively.
2, ... n, and the cross points at which the i-th horizontal line and the j-th vertical line intersect are expressed as CP (i, j) as the cross point at the i-th row and the j-th column, each cross point The vertical and horizontal lines not connected to CP (i, j) are as follows.

CP (2k-1,2k-1); Upper vertical line and left horizontal line CP (2k-1,2k); Upper vertical line and right horizontal line CP (2k, 2k-1); Lower vertical line and left horizontal line CP (2k, 2k); Lower vertical line and right horizontal line However, k = 1, 2, ... n For example, the cross point CP (2,2) is the upper line. Only the vertical line LY1 and the left horizontal line LX1 are connected to the cross point CP (2,2), and the lower vertical line LY2.
The tip of the horizontal line LX2 on the right side is not connected to the cross point P.

Since the shape of the crosspoint is changed depending on the position of the crosspoint of the crosshatch pattern 5 as described above, it is necessary to accurately identify the deviation direction of the crosshatch pattern 5 of each color of R, G and B. You can
That is, when the cross hatch pattern 5 is used, even if the positional deviation between the pattern image of G color and the pattern image of R color is as shown in FIG. since the shape of the points different, determined that the cross point CP _R of the pattern image of the color R and the like should be consistent with the cross point CP _G and not be coincident with the cross point CP _G 'of the pattern image of the color G Yes, this allows R of convergence measurement target
The vertical line (or horizontal line) of color G and the vertical line (or horizontal line) of color G can be accurately recognized. In the case of the crosshatch pattern 5 shown in FIG. 19, it is possible to measure the amount of convergence up to 1 pitch by identifying the shape of the crosspoint.

In the above-mentioned embodiment, of the upper and lower two vertical lines and the left and right two horizontal lines forming the cross point, the upper or lower vertical line and the left or right horizontal line which are not connected to the cross point are used. 4 types of cross points were formed by the combination of the above, but 16 (= 2 ⁴ ) types of cross points depending on the combination of whether or not the above four vertical lines and horizontal lines are respectively connected to the cross points. Can be formed.

Therefore, by appropriately combining the crosspoints of arbitrary shapes among the 16 types of crosspoint shapes, a more complicated crosshatch pattern 5 can be constructed as shown in FIG. 21, for example. Note that FIG. 21 is an example in which the crosshatch pattern 5 is configured by combining 10 types of crosspoint shapes.

As shown in FIG. 21, when the number of types of cross points is increased, the vertical or horizontal repetition cycle of the cross points of the same shape is increased, so that the discriminating power of each cross point is improved and an error occurs. Even if the convergence amount is large, the convergence measurement can be performed without lowering the measurement accuracy.

In the above embodiment, the display position of the crosshatch pattern 5 is moved to enable convergence measurement. However, the image pickup device 3 is moved relative to the crosshatch pattern 5 displayed on the color CRT 11. The same effect can be obtained by moving it. For example, the imaging device 3 is mounted on a mounting table that is movable in the up-down direction and the left-right direction, and the movement information of the imaging device 3 is sent to the mounting table instead of the pattern movement information, so that the mounting table is passed through the mounting table. The imaging device 3 may be moved relatively.

[0140]

As described above, according to the first aspect of the invention, the two-dimensional image signal obtained by capturing the measurement pattern image is divided into a plurality of small areas, and the measurement pattern is provided for each small area. While forming image information indicating whether or not an image is included, a small area including the measurement pattern is extracted from this image information, and it is determined that convergence measurement is not possible from the extracted state of this small area. At this time, the measurement position of the color CRT to be measured of the measurement pattern is moved to enable the convergence measurement, and when the convergence measurement becomes possible, the image is picked up by using the image signal in the small area where the convergence measurement is further performed. The focus of the optical system is adjusted so that the measurement area for convergence measurement can be set quickly and reliably. Rutotomoni, and quickly measuring pattern image of the measurement area is precisely focusing can be carried out preparation work for the convergence measurement quickly and easily.

Particularly when applied to a color CRT production line, the convergence measuring device can be automated, which contributes to the improvement of production efficiency.

Since the shapes of adjacent cross points are different, the pattern to be matched is not mistaken for the adjacent pattern. Therefore, a fine mesh pattern can be adopted so that the measurement pattern always exists in the measurement region, and the convergence measurement can be performed at any position without moving the imaging device.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a color CRT convergence measuring apparatus according to the present invention.

FIG. 2 is a circuit configuration diagram showing an embodiment of an image data detection circuit.

FIG. 3 is a waveform diagram showing a control signal for dividing a pixel signal in the horizontal direction.

FIG. 4 is a waveform diagram showing a control signal for vertically dividing a pixel signal.

FIG. 5 is a diagram in which a cross hatch pattern is displayed as a measurement pattern on a color CRT.

FIG. 6 is a diagram showing a state in which an imaging area is divided into 16 small areas.

FIG. 7 is a diagram showing a distribution of outputs of pixels of G and B colors of a CCD with respect to G and B color fluorescent images.

FIG. 8 is a diagram in which the output distribution chart of FIG. 6 is modeled and expressed by a straight line.

9A and 9B show image information of a captured crosshatch pattern, where FIG. 9A is a diagram showing a state in which a crosspoint is not in a small area adjacent to a screen boundary of an image pickup area, and FIG. It is a figure which shows the state in the small area | region adjacent to the screen boundary of an area | region.

FIG. 10 is another example in which a captured cross hatch pattern is shown by image information, and FIGS. 10A and 10B are diagrams showing a state in which a cross point is not in a small area adjacent to a screen boundary of an imaging area;
(C) and (d) are diagrams showing a state in which the cross point is in a small area adjacent to the screen boundary of the imaging area.

FIG. 11 is a flowchart showing control for setting a vertical line area and a horizontal line area from image information.

FIG. 12 is a flowchart showing control for setting a vertical line area and a horizontal line area from image information.

FIG. 13 is a subroutine for controlling the display position of the cross hatch pattern.

FIG. 14 is a flowchart of a first embodiment of display position control of a cross hatch pattern based on vertical and horizontal pitches of the cross hatch pattern.

FIG. 15 is a flowchart of a second embodiment of the display position control of the cross hatch pattern based on the vertical and horizontal pitches of the cross hatch pattern.

FIG. 16 is a flow chart of a third embodiment of the display position control of the cross hatch pattern based on the vertical and horizontal pitches of the cross hatch pattern.

FIG. 17 is a schematic configuration diagram showing another embodiment of the color CRT convergence measuring device according to the present invention.

FIG. 18 is a diagram showing a convergence state between a cross hatch pattern of G color and a cross hatch pattern of R color.

FIG. 19 is a diagram showing an example of a crosshatch pattern having different crosspoint shapes.

FIG. 20 is a diagram showing a convergence state between a G color crosshatch pattern and an R color crosshatch pattern when cross hatch patterns having different cross point shapes are used.

FIG. 21 is a diagram showing another example of a crosshatch pattern having different crosspoint shapes.

[Explanation of symbols]

 1 Color Display 2 Pattern Generator 11 Color CRT 11a Display Surface 12 Drive Control Circuit 3 Imaging Device 3a Imaging Surface 4 Device Main Body 5 Crosshatch Pattern 31 Imaging Device (CCD) 32 Imaging Optical System 33 Imaging Control Circuit 34 Focus Control Circuit 35 Signal Processing circuit 41 Image signal processing circuit 42 A / D converter 43 Image memory 44 Control unit 45 External input / output device 46 Image data detection circuit 47 Memory 48 Timing signal generation circuit 49 Focus control signal generation circuit 50 Movement control signal generation circuit 441, 447 multiplexer 462 counter 443-446 peak hold circuit 448 A / D converter

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Shinji Shimizu Inventor, Shinji 2-13-3, Azuchi-cho, Chuo-ku, Osaka City, Osaka International Building Minolta Camera Co., Ltd. (72) Inventor ▲ Tsuru ▼ Katsutani Tani 2-3-13 Osaka International Building Minolta Camera Co., Ltd. (72) Inventor, Kaoru Kikukawa 2-33-1 Azuchi-cho, Chuo-ku, Osaka City Osaka International Building Minolta Camera Co., Ltd.

Claims (2)

[Claims] 1. An image pickup means for picking up an image of a measurement pattern displayed on a color CRT to be measured and reading it as a two-dimensional image signal, and an image forming optical system for forming an image of the measurement pattern on the image pickup means. , Image dividing means for dividing the two-dimensional image signal into a plurality of small areas, and image information indicating whether or not the measurement pattern image is included in each of the small areas from the image signal of the small area. Image information forming means for forming an area, and a small area extracting means for extracting a small area including the measurement pattern image from the image information,
Determination means for determining whether or not convergence measurement is possible from the extraction state of the small area by the small area extraction means, and for the measurement on the measured color CRT to enable the convergence measurement when the convergence measurement is impossible. A moving means for moving a pattern, and a focus position detecting means for detecting a focus position of the imaging optical system by using an image signal of the small area where the convergence measurement is performed when the convergence measurement is possible, A color CRT, comprising: drive control means for driving the imaging optical system based on the detection result of the focus position detection means.
Convergence measuring device. 2. A pattern display means for displaying a measurement pattern on a color CRT to be measured, and the color CR to be measured.
An image pickup means for picking up the measurement pattern displayed on T and reading it as a two-dimensional image signal; and an image forming optical system for forming an image of the measurement pattern on the image pickup means.
The color CR for measurement based on the two-dimensional image signal
Convergence measuring device for measuring the convergence of T, wherein the measuring pattern is a crosshatch pattern in which adjacent crosspoints have different shapes from each other.