JPH05347776A - Vertical landing dislocation quantity measuring instrument - Google Patents

Abstract

PURPOSE:To shorten measuring time while keeping the accuracy of obtained measuring data by providing a means which photographs a screen by connected plural CCD cameras and divides it into plural screen areas so as to be overlapped mutually and synthesizes them by judging the boundary of each screen area in a measuring method for the vertical landing dislocation measuring instrument of an image display element. CONSTITUTION:The measuring time can be shortened while keeping the accuracy of the measuring data by comprising this measuring instrument of the plural CCD cameras 51, 52 which divide the screen into the plural screen areas, a camera change-over switch 54, a robot 53 to move the CCD cameras 51, 52 to a prescribed position, a personal computer 56 which performs the data processing of the camera change-over switch 54, a camera controller 55, and a video signal, and controls the controller 55, and an image display element driving circuit 57 to perform raster display on the image display element.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generates an electron beam for each division when a screen on a screen is divided into a plurality of divisions in the vertical and horizontal directions. The present invention relates to an apparatus for measuring a beam vertical landing deviation amount of an image display device that displays a plurality of lines by deflecting in a horizontal direction and a horizontal direction and displays an image as a whole.

[0002]

2. Description of the Related Art In recent years, various attempts have been proposed to make a color television picture tube a flat tube structure. Conventionally, this type of flat type color picture tube has a structure as shown in, for example, Japanese Patent Application Laid-Open No. 57-135590. The configuration will be described below with reference to the drawings.

As shown in FIG. 4, a back electrode 1, a line cathode 2 for emitting an electron beam, and an electron beam extraction electrode 3 are arranged in this order from the rear toward the image display screen 8 on the anode side. , An electron beam control electrode 4, a focusing electrode 5, a horizontal deflection electrode 6, a vertical deflection electrode 7, and an image display screen 8 are arranged, and the whole is housed in one vacuum container. ing. The line cathode 2 that emits electron beams is stretched in the horizontal direction, and the electron beams are distributed linearly in the horizontal direction.
Is designed to be released. Further, a plurality of lines (only 7 lines 2a to 2g are shown in FIG. 4) are provided at intervals in the vertical direction. The above-mentioned line cathode 2 is controlled so as to sequentially emit an electron beam from the upper line cathode 2a to the lower line cathode 2g for a fixed period of time.

The back electrode 1 not only prevents the generation of electron beams emitted from other line cathodes but also pushes out the electron beams only in the anodic direction.

The beam lead-out electrode 3 is composed of line cathodes 2a-2.
A plurality of through holes 10 are formed in parallel with each other in the horizontal direction facing each other at regular intervals.

The control electrode 4 is composed of a vertically long conductive plate 15 having a through hole 14 at a position facing each of the line cathodes 2a to 2t, and a plurality of control electrodes 4 are arranged side by side in a horizontal direction at a predetermined interval. Has been done. Here, the control electrode 4 corresponds the passing amount of each electron beam horizontally divided by the electron beam extraction electrode 3 to the picture element of the video signal,
Moreover, the control is performed in synchronization with the horizontal deflection timing.

The focusing electrode 5 is a conducting plate 17 having a through hole 16 at a position facing each through hole 14 provided in the control electrode 4, and focuses the electron beam.

The horizontal deflection electrode 6 is composed of a plurality of conductive plates 18 and 18 'vertically arranged along both sides of the through hole 16 in the horizontal direction. The electron beam along each picture element to which a deflection voltage is applied is horizontally deflected, and the R, G, and B phosphors 20 are sequentially irradiated on the surface of the image display screen 8 to emit light. is doing. Here, each electron beam is deflected by 2 trio.

The vertical deflection electrode 7 is composed of a plurality of conductive plates 19 and 19 'arranged in parallel in the horizontal direction at the respective intermediate positions in the vertical direction of the through hole 16, and a vertical deflection voltage is applied to the vertical deflection electrode 7 to generate an electronic beam. -The beam is deflected vertically. here,
An electron beam emitted from one line cathode is vertically deflected by eight lines by a pair of electrodes 19 and 19 '.
That is, as shown in FIG. 5, one horizontal section is R,
There are two trio of G and B, and one section in the vertical direction is composed of eight horizontal scanning lines.

In the image display screen 8, the phosphor 20 is applied in stripes on the back surface of the glass plate 21, and the metal back and black stripe carbon are applied. A high voltage is applied to the metal-backed portion of the image display device 8 to form an acceleration electrode.

The operation of the image display device using the image display element constructed as described above will be described below.

The electron beam emitted from the line cathode 2 is controlled by a video signal applied to the control electrode 4. The video signal applied to the control electrode 4 is pulse-width modulated for each of the three color signals of R, G, B corresponding to each picture element of the video signal. Since it is described in the public information of Kaisha 57-135590, it is omitted here. The electron beam controlled for each picture element is deflected by the deflection voltage applied to the horizontal deflection electrode 6 and the vertical deflection electrode 7, and the phosphor 20 of the image display screen 8 is illuminated to form an image. It is projected. A high voltage is applied to the metal-backed acceleration electrode on the back surface of the phosphor 20.

By the way, the image display device as described above is
Since it has a structure in which a plurality of image display units each having a single line cathode are connected in the vertical direction, a mechanical assembly error occurs for each image display unit. The relationship of the beam deflection amount differs for each image display unit.

For the above reasons, in order to obtain a raster with good uniformity (a raster in which the joints of each image display unit are invisible as a peculiar pattern) in the image display device using the image display element as described above, It is necessary to accurately adjust the vertical deflection voltage of the electron beam.

However, the adjustable range of the deviation of the vertical beam landing position (hereinafter abbreviated as V landing) caused by the assembly error is the dynamic range of the adjustment, the range of variation of the beam spot diameter due to the deflection distortion, and the power consumption increased by the adjustment. Because it is limited by
If the mechanical assembly error is too large, the adjustment becomes impossible. Therefore, it is necessary to measure whether the V landing deviation amount of the assembled image display element is within the adjustable range. Therefore, the V landing deviation amount is measured using the V landing measuring device described below.

In the apparatus for measuring the amount of vertical landing deviation of an image display device shown in FIG. 4, 50 is an image display device to be measured, 51 is a CCD camera, 53 is a robot for moving the CCD camera to a predetermined position, and 55 is A camera controller, 56 is a personal computer, and 57 is an image display element drive circuit for driving the image display element. First, the image display element 50 is the image display element drive circuit 5
A raster is displayed by the signal output from 7.

Next, the amount of V landing deviation is measured.
The CCD camera 51 is set in the area where the amount of V landing deviation of the image display element 50 is to be measured by using the robot 53. In one measurement, one pixel in the horizontal direction is simultaneously measured for a plurality of image units in the vertical direction. At this time, the magnification of the CCD camera 51 is set so as to satisfy the required measurement accuracy. There is. The camera controller 55 controls the CCD camera 51, A / D converts the video output output from the CCD camera 51, and transfers the video output to the personal computer 56. By processing the transferred data by the personal computer 56, it is possible to obtain the vertical landing shift amount of the plurality of vertical image units in the image pickup area of the CCD camera 51. The data measured here is stored in the data storage area of the personal computer 56 in a predetermined format. CC above processing
It is possible to measure the vertical landing shift amount of a plurality of vertical image units at the same time by performing the scanning for all the picture elements in the horizontal direction while scanning the D camera 51 in the horizontal direction. Then C
The CD camera 51 is moved vertically to the image unit in the vertical direction which has not been measured yet, and the above scanning is repeated. By repeating the above process until the final vertical image unit is measured, the V landing shift amount of the entire image display element 50 can be measured.

As described above, the raster display screen of the image display device 50 is imaged by the CCD camera 51, the video signal of the screen is analyzed, and the vertical landing shift amount is measured based on the analysis result. However, conventionally CC
The vertical landing displacement was measured with one D camera.

[0019]

In the vertical landing deviation amount measuring device for an image display device as described above, the screen of the image display device is imaged by a CCD camera, the video signal of the screen is analyzed, and based on the analysis result. The amount of vertical landing deviation is measured. In the conventional method, when measuring the amount of vertical landing deviation of a large image display device, the number of image units in the vertical direction increases as the screen becomes wider,
Since the number of pixels in the horizontal direction increases, it is not possible to use the method of changing the magnification of the CCD camera to widen the area that can be imaged at one time if the measurement accuracy is to be maintained.
One camera has a problem that the measurement time becomes longer due to the increased area.

In view of the above problems, the present invention takes a screen by a plurality of CCD cameras, divides the screen into a plurality of screen areas so as to overlap each other, and determines the boundaries of the respective screen areas based on the movement reference point of the robot and synthesizes them. By providing such means, it is possible to provide a vertical landing measuring apparatus for an image display device, which can significantly reduce the measurement time while maintaining the accuracy of the obtained measurement data.

[0021]

In order to solve the above problems, the present invention provides a plurality of connected CCD cameras and a plurality of CCDs capable of measuring the brightness of the screen of an image display device.
A robot for moving the camera to a predetermined position, a camera changeover switch, a camera controller, and a video signal data
It is composed of a personal computer for performing data processing and control of the controller, and an image display element drive circuit for displaying a raster on the image display element.

[0022]

With this configuration, the screen is divided by a plurality of connected CCD cameras into a plurality of screen areas so as to overlap each other and the boundaries of the respective screen areas are determined based on the movement reference point of the robot. By providing a means for synthesizing, it is possible to shorten the measurement time for measuring the vertical landing deviation amount of a large-sized image display element while maintaining the accuracy of the obtained measurement data.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A vertical landing displacement amount measuring device for an image display device according to an embodiment of the present invention will be described below with reference to the drawings.

In the apparatus for measuring the amount of vertical landing deviation of the image display device shown in FIG. 1, 50 is the image display device to be measured, 51 is the first CCD camera, and 52 is the second CCD.
A camera, 53 is a robot for moving the CCD camera to a predetermined position, 54 is a camera changeover switch, 55
Is a camera controller, 56 is a personal computer, and 57 is an image display element drive circuit for driving the image display element.

The screen of the image display device 50 is divided into a plurality of screen areas so as to overlap each other by a plurality of connected CCD cameras. Here, the number of CCD cameras is determined by the number of divisions (in the following example, there are two CCD cameras). The video signals of the first CCD camera 51 and the second CCD camera 52 are selected by the camera changeover switch 54 and sequentially converted into digital signals by the A / D converter in the camera controller 55 to process the image data. -Is input to the sonal computer 56.

First, the image display element 50 displays a raster according to the signal output from the image display element drive circuit 57. Next, the amount of V landing deviation is measured. The CCD camera 51 and the CCD camera 52 are provided in the area where the V landing deviation amount of the image display element 50 is to be measured.
3 is set. The CCD camera 51 and CC
The D camera 52 is set to a distance that is less than half the horizontal length of the display screen of the image display element 50. One measurement is C
With two CD cameras, a plurality of image units in the vertical direction for one picture element width in the horizontal direction are simultaneously performed for each screen area (about 1/2 of the display screen of the image display element 50). The CCD camera 51 at this time
The magnification of the CCD camera 52 is set so as to satisfy the required measurement accuracy.

The camera changeover switch 54 selects the signals sent from the CCD camera 51 and the CCD camera 52 and transfers them to the camera controller 55 in order. The camera controller 55 controls the CCD camera 51 and the CCD camera 52 and the robot 53, and A / D converts the video output output from the camera changeover switch 54 and transfers it to the personal computer 56. By processing the transferred data with the personal computer 56, it is possible to obtain the vertical landing deviation amount of the plurality of vertical image units in the image pickup areas of the CCD camera 51 and the CCD camera 52. The data measured here is stored in the data storage area of the personal computer 56 in a predetermined format. The above processing is performed for all picture elements in the horizontal direction by using the two CCD cameras while scanning the CCD camera 51 and the CCD camera 52 over approximately half of the horizontal direction of the screen, thereby making it possible to perform vertical operation of a plurality of vertical image units simultaneously. The amount of landing shift can be measured.

Next, CCD camera 51 and CCD camera 52
Is moved in the vertical direction using the robot 53 to the image unit in the vertical direction which has not been measured yet, and the above scanning is repeated. By repeating the above processing until the final vertical image unit is measured, V of the entire image display element 50 is measured.
The amount of landing shift can be measured.

In summary, the raster display screen of the image display device 50 is divided into a plurality of screen areas, each of the screen areas is imaged by a plurality of corresponding CCD cameras, the video signal on the screen is analyzed, and the image signal of the screen is analyzed. By measuring the vertical landing deviation amount, the vertical landing deviation amount can be accurately measured in a short time.

[0030]

As described above, according to the present invention, it is possible to greatly reduce the time required for measuring the vertical landing deviation amount of a large image display device while maintaining the accuracy of the measured data to be measured. It will be possible.

[Brief description of drawings]

FIG. 1 is a block diagram of a vertical landing measuring apparatus for an image display device according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of an image display device which is a target of the present invention.

FIG. 3 is an enlarged view of a phosphor screen of the image display device.

FIG. 4 is a block diagram of a conventional vertical landing measuring device for an image display device.

[Explanation of symbols]

50 image display device 51 first CCD camera 52 second CCD camera 53 robot for moving the CD camera to a predetermined position 54 camera changeover switch 55 camera controller 56 personal controller 57 image display for driving an image display element Element drive circuit

Claims (1)

[Claims] 1. A vertical landing shift of an image display device, which captures a screen of the image display device with a CCD camera, analyzes a video signal of the screen, and measures a vertical landing shift amount of an electron beam based on the analysis result. In the measuring method of the quantity measuring device, the above screen is grasped by a plurality of CCD cameras, and a plurality of screen areas are divided so as to overlap each other, and a means for judging the boundary of each screen area and synthesizing the screen is provided, which greatly reduces the measurement time. A vertical landing displacement amount measuring device for an image display device, which is realized.