JPS5974780A - Method and device for measurement of convergence - Google Patents

Abstract

PURPOSE:To obtain effectively the quantity of misconvergence, by picking up a pattern for measurement with a CRT to be measured and then obtaining a measurement pattern of each emitted light color on the basis of the position information of each light emission pattern obtained previously from said picked-up measurement pattern. CONSTITUTION:A pattern generator 10 generates the white color pattern to the entire surface of a three color picture receiving CRT1 to be measured, and the information is displayed by a TV electronic circuit 11. At the same time, an optical filter 3 is revolved by a filter switching mechanism 4 to set a blue separating filter. Under such conditions, a specific area of a display pattern of the CRT1 is picked up by an ITV camera 2. This image pickup signal undergoes an A/D conversion through an image memory circuit 6 and then an aritmetic control 7 to obtain the region information. Then measurement patterns are picked up at a time and not detected in time division for each color. Thus the quantity of misconvergence can be calculated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a convergence measuring method and a measuring device for measuring the convergence of three electron beams in a three-color picture tube. Regarding the improvement of

[Technical background of the invention]

Conventionally, as a method for measuring the convergence of a three-color picture tube, for example, a color picture tube as a picture tube to be measured has a pattern (measurement pattern) for convergence measurement.
This display pattern is separated into blue, red, and green light emitting colors using a golden separation filter, and images are taken with an industrial television (ITV) camera for each monochromatic gloss turn. For each luminescent color, the luminescent center of the measured gloss turn is determined and the relative position deviation is obtained as information from Miscompersence.

[Problems with background technology]

However, in this conventional measurement method, the measurement pattern of each color is detected in a so-called time-division manner, which causes fluctuations in the power supply, generation of noise, and interference between the television electronic circuit and ITV camera while detecting the measurement pattern of each color. If the brightness of the color picture tube display surface changes due to synchronization with the iJ? This method has the drawback that the measurement conditions for the turns change, and as a result, accurate misconception amounts cannot be obtained.

Another convergence measuring method is to emit electron beams corresponding to each emission color in a time-division manner without using a color separation filter, thereby obtaining measurements for each emission color. However, even with this method, there is still a time difference until the measurement pattern of each color is obtained, and therefore, as in the case of using the color separation filter, the influence of power supply fluctuations etc. cannot be avoided. Furthermore, in this type of method, it takes time to stabilize the light emitting state after switching the electron beams of each color, so a large amount of time is required for measurement, resulting in poor measurement efficiency.

[Purpose of the invention]

The present invention enables measurement f-turns to be detected simultaneously without having to detect each emission color separately, thereby eliminating temporal fluctuation elements and improving convergence measurement accuracy.
Another object of the present invention is to provide a convergence measuring method and a measuring device thereof, which can shorten measurement time and improve measurement efficiency.

[Summary of the invention]

In order to achieve the above object, the present invention first displays a white color/main turn on a picture tube to be measured, images the display pattern for each emitted color, and uses the imaged signals to display a pattern on the display surface of the picture tube to be measured. The positional information of each color emission pattern is obtained, and then the measuring tube is displayed with a 4' turn for measurement, and this measurement/4' turn is imaged. The measured nosetan of each luminescent color is obtained based on the position information, and the amount of υ misconvergence is determined from the relative positional relationship of each of these monochromatic colors.

[Embodiments of the invention]

FIG. 1 is a schematic diagram of a consense measuring device according to an embodiment of the present invention, and in the figure, numeral 1 indicates a three-color picture tube (c-cRT) as a picture tube to be measured. This C-CRT 1 is set in a fixing device (not shown).

An industrial television (ITV) camera 2 is placed facing the display surface 1a of this 'C-CRT 7, and an optical filter 3 is placed between this ITV camera 2 and the C-CRT 1. has been done. This optical filter 3 includes, for example, a circular plate 3a and blue, red, and green color separation filters 3b and 3c as shown in FIG.

3d and a neutral density filter 3e are arranged at an interval of 90 degrees from each other, and are switched by a filter switching mechanism 4. The filter switching mechanism 4 has a step motor 4a as shown in FIG. 2, and the power of the step motor 4a is transmitted to the disk 3a via a full gear mechanism 4b.
Accordingly, the desired filter is selected by rotating the disc 3a. Note that this filter selection control is performed by the filter switching circuit 5.

By the way, the imaging signal of the ITV camera 2 is led to an image memory circuit 6 consisting of an A/D conversion circuit and a buffer memory, where it is temporarily stored as digital image information, and then led to an arithmetic control circuit 7. The arithmetic control circuit 7 has, for example, a microprocessor as a central processing unit, and controls the operation of each part of the device according to a control program stored in the memory 8, and also calculates the imaging information from the image memory circuit 6 to achieve convergence. demand. Further, the arithmetic control circuit 7 stores the arithmetic results in the memory 8 and causes the data output device 9 to display or record the results. Note that 10 is 2 according to instructions from the arithmetic control circuit 7.
A pattern generator generates all kinds of image patterns and supplies these patterns to the television electronic circuit 1 for display on the C-CRT 1.

Next, the measurement method of the heather embodiment will be explained based on the above configuration. First, with respect to the C-CRT 7 set at a predetermined position, a pattern generator 10 generates a white pattern 1 code signal over the entire surface, and the television electronic circuit 11 displays this. At the same time, the filter switching mechanism 4 rotates the optical filter 3 to first set the front separation filter 3b, and in this state, the ITV camera 2 is connected to the C-CR.
Display of T1: Image a specific area of the 4' turn.

Then, an image signal is obtained by the ITV camera 2,
The image pickup signal is A7D converted by the image memory circuit 6 and guided to the arithmetic control circuit 2. Then, this arithmetic control circuit 7 converts it into binary information, for example, from the length AL of the "H" level portion of VS shown in FIG. 3 to the center line XO of each phosphor.
The position of filJ
The area information BXn is set in the whitebait direction and the minus direction, and is stored in the BXn f memory 8. Once the area information BXn of the blue phosphor is calculated in this way, the light separation filter 3cf of the optical filter 3 is set, and the area information RXn of the red phosphor is obtained from the imaging signal as in the case of the pre-separation filter 3b. f is determined and stored in the memory 8. Similarly, the klO color separation filter 3df is set, the corresponding phosphor area information GXn f is obtained, and the memory 8
to be memorized. Figure 4 (a), (b), and (e) are the areas of the front, red, and green color light emitting patterns, respectively.
It shows the information. Note that the size of the calculation area for these area information is based on the maximum con- sense range in the X direction (
XL) in the figure, and the length in the Y direction is determined to be ys) in the figure, which corresponds to the irradiation diameter of the electron beam, which will be described later.

Thus, area information B for each of the red, red 2, and green phosphors
After completing the calculation of
A white dot pattern (DP in the figure) as shown in the figure is generated and displayed on the multi-turn iC-CRT 1. Then, the optical filter 3ff is rotated and the neutral density filter 3ef is set, and in this state, the ITV camera 2 images a predetermined area including, for example, one of the white dots and the turn DP. FIG. 6 shows the imaging area, and its thickness is set to the same length XL in the X direction as when calculating the area information, and to the maximum convergence range YL in the Y direction.

In the figure, ■, @, and θ indicate the irradiation areas of the blue, red, and green electron beams, respectively. ) only emit light.

The image signal is A/D converted by the image memory circuit 6 and sent to the arithmetic control circuit 7 in the same way as when calculating the area information. The arithmetic control circuit 7 calculates only the A/D conversion information in each color area based on the area information already stored in the memory 8, and calculates the luminescent light contained in the image. Calculate all the centroids of the light bodies (1 extra line in Fig. 6), and calculate each of these centroids, for example, among the centroids of BO, RO, and Go in Fig. 6, each of the blue and other luminescence with respect to the centroid GO of the green light-emitting phosphor. The separation distance BX between the center of gravity BO and RO position of the fluorescent body.

BY, RX, and RY are each calculated, and the results of these calculations are recorded or displayed on the data output device 9 as convergence information.

With the method of this embodiment, after obtaining the region information BXn, RXn + GXn ft for each color, '4y:', the measurement pattern is not detected in a time-division manner for each color, but is imaged simultaneously to avoid misconvergence. With Ω that can be calculated on the basis of VJ-, highly accurate measurement results can be obtained without being affected by power supply fluctuations, etc., as in conventional methods. Also,
Compared to the case where electron beams are generated separately for each color, this method has the advantage that measurement can be performed in a shorter time.

Note that the present invention is not limited to the above embodiments.

For example, in the above embodiment, three color separation filters were used to detect the area information of each of the blue, red, and green phosphors. Area information for the other two colors may be obtained by predicting from the detected area information. In this way, n1l) the required time can be further shortened. Furthermore, the measurement pattern is not limited to the dot pattern, but may also be a black-and-white pattern.

In addition, the signal processing method and calculation method of image pickup information, and the configuration of each part of the apparatus can be modified in various ways without departing from the gist of the present invention.

〔Effect of the invention〕

As described in detail above, according to the present invention, the positional information of each color light emission and each turn is obtained in advance, and then the measured i+turn is imaged and this pattern is compared with the above positional information to determine the measurement pattern. Since each light emitting color is separated and the co/parity is calculated from this separated information, the measurement pattern can be detected simultaneously without having to detect each emitted color separately. A convergence measurement method and measuring device that can improve convergence measurement accuracy by removing temporal fluctuations, shorten measurement time, and improve measurement efficiency? L-Can be provided.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a convergence measuring device according to an embodiment of the present invention, FIG. 2 is a perspective view showing the configuration of a part of the same device, and FIGS. 3 to 6 are each according to an embodiment of the present invention. Figure 3 is a schematic diagram showing the imaging signal processing method;
Figures (a) to (c) are schematic diagrams showing area information of each phosphor;
FIG. 5 is a schematic diagram showing the measurement pattern, and FIG. 6 is a schematic diagram showing the measurement and turn imaging results. 1... Color picture tube (, c-CR'r), 2...
ITV camera, 3... Optical filter, 4... Filter switching mechanism, 5... Filter switching circuit, 6... Image memory circuit, 7... Arithmetic control circuit, 8... Memory,
9...Data output device, 10...Riya turn generator,
1. Television electronic circuit.

Claims (2)

[Claims] (1) Display a white pattern on the color picture tube to be measured,
This display gloss turn is imaged for each fluorescent color, and position information of each color light emission pattern on the display screen of the picture tube to be measured is detected for each light emission color from the image signal, and then specified to the picture tube to be measured. Measure/display 4' turn,
4 This measurement turn is imaged and the imaging signal is used to obtain the measurement turn 9 for each emission color based on the detection position information of the light emission turn 4, and the relative positional relationship of these measurement turns is calculated based on the simis comparence. A convergence measurement method characterized by determining the amount. (2) Specific measurement A for white 9 turns and convergence measurement for the color picture tube to be measured? means for selectively displaying the turns; an imaging means for taking images of each of the 4' turns displayed at the same position on the display screen of the front 4' arrangement measuring picture tube for each emission color; a color filter unit that separates the turn for each emission color; and a color filter unit that detects positional information of each color emission pattern on the display screen of the picture tube to be measured from imaging information obtained for each emission color by the imaging means. and calculation means for calculating the measurement pattern of each luminescent color IIF based on the positional information of the luminescent gloss turns of all the above-mentioned colors obtained in the measurement pattern obtained by the imaging means, and also calculates the amount of misconvergence from the relative positions of the measured gloss turns. A convergence measuring device characterized by comprising: