JPS6220222A - Adjusting device for color television receiver - Google Patents

Abstract

PURPOSE:To enable the measurement of the deviation amount of the electron beam to be conducted automatically and quantitatively by providing a detecting means for detection of the color density of the color picture tube of a television receiver and a data processing means for operation of the detected data obtained by the said detecting means. CONSTITUTION:The green monochromic picture signal is generated in the pattern generator circuit device 7 to be sent to the color picture tube 9 in the color television receiver. The green monochromic picture is displayed on the cathode ray tube 9. This display is observed with the ITV camera 11 through the green transmission filter 10. The color signal obtained with this camera 11 is sent to the camera control unit CCU12 to be written in the picture memory of the picture processing device 13 as the density data. In the picture processing device 13 the operation by the CPU is performed to the density value of the memory address of the location corresponding to the measuring point on the cathode ray tube 9 and the result is stored respectively. From the result of the operation the deviation direction and the deviation amount of the electron beam can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a device for improving the brightness of emitted light in a color television cathode ray tube.

<Prior art> As shown in Figure 3, the basic structure of a color television CRT has conventionally consisted of three types of electron guns I for R, G, and B that emit electron beams, and a gun approximately 10 nm in front of the fluorescent surface. A shadow mask 2 is installed parallel to the fluorescent surface to illuminate only the corresponding fluorescent points with three types of electron beams, and a shadow mask 2 that emits light in each color of R@G@B (red, green, and blue). 90 to 100 point-like phosphors
The fluorescent surfaces 3 (Fig. 3(b)
) i An enlarged view of the fluorescent surface is shown).

In addition, Fig. 4 shows a side sectional view of a color TV CRT.
There is a purity magnet 5. A deflection coil 6 and the like are provided. As is well known, the purity magnet 5 is composed of a set of two annular magnets, and by applying a magnetic field to the electron beam passing through it, the trajectory of the electron beam can be changed in any direction. It can be modified by any amount. The deflection coil 6 is capable of greatly bending the electron beam by the magnetic field it provides, and scattering the electron beam over the entire surface of the fluorescent surface 3.

It goes without saying that in the color television cathode ray tube as described above, it is important to accurately irradiate each fluorescent spot with an electron beam from the viewpoint of color purity. If the electron beam deviates from the fluorescent spot that it should irradiate, this is called a mis-landing, and in this case color mixing occurs and the image becomes difficult to see.

Conventionally, such electron beam deviations have been corrected by a skilled worker using a microscope (50 to 100x magnification) to visually measure whether or not the center of the electron beam and the center of the fluorescent spot are accurately aligned. was. Then, the amount of deviation of the electron beam was estimated empirically from the edge shape of the shadow mask projected by the electron beam onto the phosphor, and correction was performed. However, with this method, ■ there is a large influence due to variations in the edge shape of the shadow mask, and ■ the measurement method is not quantitative, so the measurement results vary greatly from person to person.
■In order to carry out accurate measurements, the operator is required to be highly skilled, which poses a problem in that the operator is highly fatigued.

<Objective> The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to automatically and quantitatively measure the amount of deviation of an electron beam.

<Embodiment> Hereinafter, an embodiment of a color television adjustment device according to the present invention will be described with reference to the drawings.

FIG. 1 shows a configuration explanatory diagram of an embodiment of a color television adjustment device according to the present invention.

7 is an NTSC pattern Jay, rake circuit device,
A green monochromatic image signal is created by this device and sent to a color television cathode ray tube 9 in a color television set 8. A monochromatic green image is displayed on the color television cathode ray tube 9. The display on this color TV cathode ray tube 9 is filtered using a green transmission filter.
Observe with the ITV camera 11 through O. This ITV camera II is set so as to be movable in the X-Y directions.

The image signal obtained by the ITV camera 111 is sent to the camera control unit 12, and further written as gray scale data to the image memory in the image processing device I3.

In the image processing device 13, the CPU performs calculations on the density values of the memory addresses at the positions corresponding to the measurement points m to (6) of the color television cathode ray tube 9, and stores the results. Further, since the direction and amount of deviation of the electron beam are determined by this calculation result, these are displayed on the monitor 14.

Furthermore, the measurement procedure will be explained in detail.

Figure 2 shows a diagram of the principle of the measurement method. I5 is a measurement deflection coil, and when the current flowing through the measurement deflection coil I5 is 0, the ammeter displays 0 as shown in B. If the electron beam positioning is accurate, the display is as shown in B' ( Gart band 16.1
At the center of 6, each bright spot of R, G-B 17. IT, 1
'l get. Also, when the current flowing through the measuring deflection coil 15 is negative, the ammeter display is negative as shown in A.
Since a downward magnetic field is applied to the electron beam, R@G and B bright spots 17, 17.17 are obtained by overlapping the guard band 16 as shown in A'. In addition, when the current flowing through the measurement deflection coil 15 is positive, the ammeter display is positive as shown in C, and since a magnetic field is applied upward to the electron beam, Cl
(However, A/
(opposite side) RGB bright spots 17, 17, 17 are obtained.

Here, when the current flowing through the measurement deflection coil 15 is 0, the concentration values at the measurement points 1 to 1 shown in FIG. The measurement point m to the concentration value of the country (value of ) is -1 to L4.
−6, and the density value of the measurement point m − when the current flowing through the measuring deflection coil 15 is 10 is calculated and stored in the image processing device 13 as ˜L6.

(1) ~ If the center of the electron beam spot and the center of the fluorescent point match each other at each measurement point in the mouth, Lmi
l-ml 6).

If the above calculations are executed by the CPU in the image processing device 13 and the results are displayed on the monitor 14, the operator can quickly and accurately obtain information regarding the deviation of the electron beam and perform adjustments. Specifically, the purity magnet 5 or the deflection coil 6 is adjusted based on the content displayed on the monitor 14.

<Effects of the Invention> According to the present invention described above, the measurement of the deviation of the electron beam can be quantitatively understood, so that the deviation can be adjusted appropriately. Furthermore, since the displacement can be measured more quickly and accurately than the conventional empirical method performed by an operator, the time required for adjustment can be significantly shortened.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the configuration of one embodiment of the color television adjustment device according to the present invention, Fig. 2 is a principle diagram of the measurement method, and Fig. 3 (
a+ is a perspective view of a color TV CRT, same figure (1)
4 shows an enlarged view of the fluorescent surface, and FIG. 4 shows a side sectional view of a color television cathode ray tube. In the figure, 1: electron gun, 2: shadow mask, 3: fluorescent surface, 4: neck, 5: purity magnet), 6: deflection coil, 7: pattern generator circuit device, 8: color television set, 9: Color television cathode ray tube, 10: green transmission filter, 11: ■TV camera, 12: camera control unit, 13: image processing device, 14: monitor, 15: measurement deflection coil, 16: guard band,
17: Bright spot.

Claims (1)

[Scope of Claims] 1. Magnetic field application means for selectively causing mislandings in opposite directions on a color television cathode ray tube; and detection means for detecting the color density of a color television cathode ray tube when mislandings in opposite directions occur. . A color television adjustment device comprising: data processing means for comparing and calculating detection data obtained by the detection means.