JPH08185812A - Color crt display - Google Patents

Abstract

PURPOSE: To regulate traveling dislocation of electron beams being changed by the direction at the time of use. CONSTITUTION: In a color CRT display having a convergence magnet 12 to regulate respective electron beams from an electron gun so as to simultaneously pass through a single shadow mask hole, the display is provided with a coil 19 coaxially arranged with the convergence magnet 12 and an electric current regulator to regulate an electric current to be fed to this coil. Therefore, component force of geomagnetism is negated.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a color CRT display.

[0002]

2. Description of the Related Art A color CRT display is equipped with a convergence magnet so that three electron beams from its electron gun can simultaneously pass through the holes of one shadow mask.

As a result, each electron beam that has passed through the holes of the shadow mask emits red (R), green (G), and blue (B) fluorescent substances formed adjacent to the back surface of the face panel. Each of them is accurately irradiated and excited.

Then, the adjustment by the convergence magnet is usually performed in a state where the face panel is directed in a specific direction (for example, the east side) at the time of assembling.

[0005]

However, it has been pointed out that, in the color CRT display adjusted in this way, color shift occurs at the stage of use by the user.

That is, when assembling a color CRT display, if the face panel is adjusted by directing it to the east side, for example, the direction of the electron beam is deflected to the electron beam with the influence of the geomagnetism included. It will be adjusted without any deviation in the running direction.

Therefore, when the user uses the color CRT display with its face panel oriented in a direction other than the east side, a component force of geomagnetism acts on the electron beam from a direction orthogonal to the beam direction, This is because the electron beam will be shaken (shift in the traveling direction).

The present invention has been made under such circumstances, and an object of the present invention is to provide a color CRT display capable of adjusting the traveling deviation of the electron beam which changes depending on the direction of use.

[0009]

In order to achieve such an object, the present invention basically adjusts so that each electron beam from an electron gun passes through a hole of one shadow mask at the same time. A color CRT display provided with a convergence magnet is characterized by including a coil arranged coaxially with the convergence magnet and a current regulator for adjusting a current flowing through the coil.

[0010]

According to the color CRT display thus constructed, the component force exerted on the terrestrial magnetism electron beam by the magnetic force generated from the coil through which the current adjusted by the current regulator flows can be canceled.

Therefore, regardless of the direction of the display used, the traveling direction of the electron beam is the same as that when adjusted by the convergence magnet, and there is no occurrence of color shift.

From this, it becomes possible to adjust the traveling deviation of the electron beam which changes depending on the direction in use.

[0013]

FIG. 2 is a sectional view showing an embodiment of a color cathode ray tube according to the present invention.

In the figure, there is an electron gun assembly 2 which emits electrons as a beam. This electron gun assembly 2 includes R (red), G (green), and B (blue) electron guns 2a, 2
It has an integrated structure of b and 2c and is adapted to emit the electron beams 4a, 4b and 4c from the respective electron guns.

Further, the phosphor screen 11 is opposed to the electron gun assembly 2.
Are arranged, and the phosphor screen 11 is provided with regions of respective pixels arranged in a matrix.

Adjacent to a region corresponding to one pixel of the phosphor screen 11, phosphors emitting R (red), G (green) and B (blue) respectively by irradiation with electron beams 4a, 4b and 4c. One pixel configured in this way is provided for each electron gun 2a, 2b, 2c of the electron gun assembly 2.
The electron beams 4a, 4b, and 4c from the above are controlled to have a predetermined color by irradiating the corresponding phosphors under the control of the shadow mask 10 described later.

The electron gun assembly 2 and the phosphor screen 11 are enclosed by an envelope 20 made of glass, and the phosphor 11 is contained in the panel portion 7 of the envelope 20.
It is arranged so as to be attached to the inner wall surface of the part called. Here, the panel portion 7 serves as a display portion of the cathode ray tube, and an observer can recognize the color development of the phosphor screen 11 through the envelope 20.

The portion of the envelope 20 that encloses the electron gun assembly 2 is called a neck portion 1, and the portion between the neck portion 1 and the panel portion 7 is called a funnel portion 5.

A deflection yoke 3 is arranged on the outer circumference of the funnel portion 5 of the envelope 20, and the deflection yoke 3 sequentially irradiates each pixel on the phosphor screen 11 with an electron beam from the electron gun assembly 2. The scanning (deflection) for moving is performed.

The envelope 2 in the funnel portion 5
Inside 0, an internal magnetic shield 9 is arranged so as to surround a region where the electron beam is deflected.

Further, in the envelope 20 of the panel portion 7,
A shadow mask 10 for controlling the irradiation amount of each scanned electron beam from each electron gun constituting the electron gun assembly 2 to each corresponding phosphor is arranged to face the phosphor screen 11. There is.

That is, as shown in FIG. 3, the shadow mask 10 faces the pixels on the phosphor screen 11 so as to face the holes 1.
It is made of a thin plate material provided with 0A, and passes only the component for emitting the phosphor of the color corresponding to the electron beam from each electron gun 2a, 2b, 2c through the hole 10A.

A convergence magnet 12 is arranged around the neck 1 so that each electron beam can be adjusted to pass through each hole 10a of one shadow mask 10 at the same time.

Here, this convergence magnet 1
Adjustment by 2 can be done when assembling the CRT display.
What is done with the face panel 7 oriented in a specific direction (for example, the east side) is as described above.

FIG. 1 is a configuration diagram showing details of the convergence magnet 12 applied to this embodiment.

The convergence magnet 12 includes
Paired 2-pole magnets 12a and 12b, Paired 4-pole magnet 1
3a, 13b and paired 6-pole magnets 14a, 14b
In addition, when the CRT display that has become a product is used by orienting it in a direction other than the east side, it cancels out the component force of geomagnetism (geomagnetic component that causes a deviation in the traveling of the electron beam). The coil 19 for this purpose is integrally provided.

A current flows from the power source to the coil 19 via a current regulator (not shown), and the current value can be varied by the adjustment by the current regulator.

According to the color CRT display thus constructed, the component force exerted on the geomagnetic electron beam by the magnetic force generated from the coil through which the current adjusted by the current regulator flows can be canceled.

Therefore, regardless of the direction of the display used, the traveling direction of the electron beam is the same as when adjusted by the convergence magnet 12, and the occurrence of color shift is eliminated.

From this, it becomes possible to adjust the traveling deviation of the electron beam which changes depending on the direction in use.

In the above-mentioned embodiment, the current flowing through the coil can be adjusted arbitrarily by using the current regulator. However, the present invention is not limited to this. For example, a means for inputting the arrangement direction of the display is provided by some method, and the current to be passed through the coil can be automatically set based on the information input to this means. It goes without saying that it is good.

In the above-described embodiment, the coil 19 is formed integrally with the convergence magnet 12, but the coil 19 is not necessarily limited to this and may be formed separately from the convergence magnet 12. Needless to say.

[0033]

As is apparent from the above description,
According to the color CRT display of the present invention, it becomes possible to adjust the traveling deviation of the electron beam which changes depending on the direction of use.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a convergence magnet used in a color CRT display according to the present invention.

FIG. 2 is a schematic configuration diagram showing an embodiment of a color CRT display according to the present invention.

FIG. 3 is an explanatory diagram for explaining a function of a shadow mask used in the CRT display according to the present invention.

[Explanation of symbols]

10 ... Shadow mask, 12 ... Convergence magnet, 19 ... Coil (geomagnetic component canceling coil).

Claims (2)

[Claims] 1. A color CRT display having a convergence magnet for adjusting each electron beam from an electron gun to pass through a hole of one shadow mask at the same time, and a coil arranged coaxially with the convergence magnet. A color CRT display comprising: a current regulator that regulates a current flowing through a coil. 2. The color CR, wherein the coil is formed integrally with a convergence magnet.
T display.