JPS63231845A - Electron gun for color cathode-ray tube - Google Patents

Abstract

PURPOSE:To jointly use existing inclined cylinder sections to obtain the desired concentration angle and improve the focus characteristic for each type by providing an electric field correcting electrode in an electrode with the inclined cylinder sections. CONSTITUTION:An electric field correcting electrode 6A having electron beam passing holes 6As1, 6As2, 6Ac is coaxially arranged facing the inclined cylinder sections 6S1, 6S2 on both sides and a cylinder section 6C at the center inside the fifth grid 6. Likewise, an electric field correcting electrode 7A having electron beam passing holes 7As1, 7Ag, 7As2 respectively is coaxially arranged facing the inclined cylinder sections 7S1, 7S2 on both sides and a cylinder section 7C at the center inside the sixth grid electrode 7. Thereby, the concentration angle of an electron beam can be obtained. Accordingly, the focus characteristic can be improved by combining with various types of existing grid electrodes having the representative size with the largest concentration force.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] - The present invention relates to an in-line type color cathode ray tube electron gun, and particularly to an electrode structure of an electron lens forming electrode suitable for improving focus characteristics.

[Conventional technology]

In an in-line type electron gun, each electron beam is arranged on one plane, so the diameter of the main lens is smaller than that in a delta type electron gun. Due to constraints such as deflection power and convergence, the smaller the diameter of the neck, the better; however, if the diameter of the main lens is even smaller, the focus characteristics will deteriorate.

In addition, the gap between the outer diameter of the electron gun and the inner diameter of the neck is set to 1 m, for example, in order to reduce the influence of undesirable electron radiation.
m or more, and there are many restrictions that prevent the diameter of the main lens from being increased. Therefore, a multi-stage focusing electron gun has been proposed as a means to improve focusing performance under many constraints. This multi-stage focusing electron gun can focus the electron beam gently and can improve the spherical aberration of the electron lens.

FIG. 3 is a partially cutaway view of a typical multi-stage focusing electron gun. In the figure, the electron gun has a cathode 1. 1st grid 2. 2nd grid 3. Third grid 4. 4th grid 5. It is composed of a fifth grid 6 and a sixth grid 7, and the main lens is the third grid 4. 4th grid 5
The fifth grid 6 forms one lens system, and the fifth grid 6 and sixth grid T form another lens system. Further, the third grid 4 and the fifth grid 6 are electrically connected, and a focus voltage, for example, about 7 KV is applied, and the fourth grid 5 and the sixth grid 7 are electrically connected, and an anode voltage, for example, is applied. Approximately 25 KV
is applied, and the entire electron gun is a multi-stage focusing electron gun that combines pi-potential type and uni-potential type, and its focus characteristics are greatly improved.

The structure of such an electron gun for a color cathode ray tube is described in, for example, Japanese Patent Laid-Open No. 57-63750.

[Problem that the invention seeks to solve]

However, when the multi-stage focusing electron gun with the above-mentioned configuration is applied to, for example, a 22-inch inner color cathode ray tube, sufficient focusing characteristics can be obtained for practical purposes. Because the distance from the electron gun to the phosphor surface is different for the transition of It is necessary to prepare grids, and when considering specifications for new sizes, it takes a long time to manufacture electrode parts.
However, it is not possible to start up mass production in a timely manner. In other words, it is necessary to determine the amount of inclination of the cylindrical parts on both sides in the fifth and sixth grids for each product type, and the manufacturing period
There was a problem in that it took a long time to decide on specifications.

The present invention has been made in view of the above-mentioned conventional problems, and its purpose is to obtain a desired focusing angle by sharing the existing inclined cylindrical portion, and to provide focusing characteristics for each product. An object of the present invention is to provide an electron gun for a color cathode ray tube that can be improved.

[Means for solving problems]

The present invention provides an electric field correction electrode within an existing grid electrode having an inclined cylindrical portion.

[Effect]

In the color cathode ray tube electron gun according to the present invention, by providing an electric field correction electrode, the electron beam is moved approximately in parallel,
The concentration angle is controlled.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a partial sectional view showing an embodiment of an electron gun for a color cathode ray tube according to the present invention, and the same parts as in the previous figures are given the same reference numerals. In the figure, the fifth grid 6
Inside, there are slanted cylindrical parts 6J*6112 on both sides.
Coaxially with the central cylindrical portion 6c, one electric field correction electrode having each electron beam passing hole 6Aa1m 6As* +6Ac is disposed to face each other. Similarly, inside the sixth grid electrode 1, inclined cylindrical portions 7ss +
Electric field correction electrodes IA having respective electron beam passing holes 7AI11, 7As2, and 7Ac are arranged facing each other on the same @11 along with 7 m2 and the central cylindrical portion γ.

According to such a configuration, the inclined cylindrical portions 6sl, 6sz + Be on both sides of the fifth grid 6 and the electron beam passing holes 6Asl, 6Asz + Be of the electric field correction electrode 6A
Since an electron lens is formed by the electric field between the grid 6c and the fifth grid 6c, the apparent upward slope of the electron lens formed only by the fifth grid 6 is corrected. The concentration angle of the electron beam will be corrected and controlled.

Furthermore, by providing the electric field correction electrode 7A for the sixth grid T as well, the apparent upward inclination f+ of the electron lens is corrected in the same way as described above.

Therefore, the cylindrical parts 6sl, 6' in the fifth grid 6
The axial distance between the opposing electron beam passing holes 6As1, 6Asz, and 6Ac of the electric field correction electrode 6A is 11 and the cylindrical portion 7at+7gx in the sixth grid T.
+70 and each electron beam passing hole 7As of the electric field correction electrode 7A
z +7Asz +7Ac The axial distance between the opposing sides is t! Since the distance X at which the electron beam is concentrated in the direction of the central axis S is approximately inversely proportional as shown in FIG. This results in an electron beam concentration of .

In the above-mentioned embodiment, the case where the electric field correction electrodes were provided in both the fifth grid 6 and the sixth grid γ was explained, but the present invention is not limited to this, and the electric field correction electrodes are provided in at least the fifth grid 6. It's good to have it inside. That is, when the shield cup is provided in the sixth grid T, the shield cup is disposed on the fluorescent surface side of the tip end of the sixth grid, so it is either impossible to control the concentration angle to a large extent, or By providing it in the 5 grid 6, the concentration angle can be greatly controlled and a large part of the concentration angle can be determined.

Then, by simultaneously providing it in the sixth grid γ,
If the concentration angle can be finely adjusted, it becomes possible to set the desired electron beam concentration angle.

In the above-described embodiments, the electric field correction electrode has a plate-like pole, but the present invention is not limited to this. Needless to say, the same effect as described above can be obtained.

〔Effect of the invention〕

As explained above, according to the present invention, by providing an electric field correction electrode within an existing grid electrode having an inclined cylindrical portion, the concentration angle of the electron beam can be controlled, so that the concentration angle can be maximized. By combining this with the existing grid electrodes of each type having a large representative dimension, it is possible to improve the focusing characteristics and to achieve extremely effective effects such as making it possible to standardize the electrodes.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part showing a set of embodiments of an electron gun for a color cathode ray tube according to the present invention, and FIG. 2 shows the relationship between the distance in the axial direction of the electric field correction electrode and the distance at which the electron beam is concentrated in the central axis direction. 3 are partially cutaway views showing a conventional electron gun for a color cathode ray tube. 5mmam 5th grid, 5s+ 1 682 +
6c conflict...cylindrical part, 6A...electric field correction electrode, 6
A! ! ! , 6As2, 6c...electron beam passing hole,
7m race** 6th grid, 7sl, 782, 7c...
, Cylindrical part, 7A --- Electric field correction electrode, 7A811
γAsz, 7c...Electron beam passage hole. N〈 19= Fig. 1 6: 57”18t” 5As+, 6Asz, 6c: 7 colors soil Hi...-4 Interpreter translation-7 Ni 67°゛su, 7 To 7S+, 7S2.7C ; i II ”P7A: Real estate brokerage 5-7As+, 7AS2, 7C: @= 4-c remote control 1
Sushi Figure 2 □ 7.72 (mm) Figure 3

Claims (1)

[Claims] 1. a first electrode means for directing at least two electron beams along initial paths parallel to each other toward a phosphorescent surface; a second electrode means for focusing the electron beam on the fluorescent surface, the electrode means having an opening whose central axis coincides with the electron beam passage, and which are arranged facing each other at a distance from each other, and are arranged opposite to each other at a distance from each other; An electron gun for a color cathode ray tube, the electron gun for a color cathode ray tube having one end inclined with respect to the central axis, characterized in that an electric field correction electrode is provided within the electrode having the inclined cylindrical portion.