KR100474356B1 - Electron gun for CRT - Google Patents

Abstract

According to the present invention, a plurality of electron radiating means for emitting an electron beam, a three-pole portion comprising a control electrode and an acceleration electrode for adjusting and controlling the radiation amount of the electron beam and a plurality of electrostatic focusing lenses for focusing the electron beam on a screen In the electron gun for a color cathode ray tube including a focusing and an acceleration electrode, the plurality of electron emitting means and a plurality of electrodes are sequentially arranged in the tube axis direction spaced apart from each other, acceleration electrode (G2) of the three-pole portion forming electrode The slot is formed around the electron beam through hole of the acceleration electrode is characterized in that it is formed to be 80% or more of the horizontal or vertical size of the electron beam through hole.

According to the present invention, the resolution can be improved by improving the peripheral resolution and reducing the size of the horizontal pixel (H-spot), and designing a desensitization of the pixel size according to the focusing electrode voltage in the vertical direction of the pixel.

Description

Electron gun for color cathode ray tube {Electron gun for CRT}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron gun for color cathode ray tubes, and more particularly, to prevent and improve resolution degradation at the periphery of a screen.

Generally, a cathode ray tube (brown tube) is a special vacuum tube that converts an electric signal into an optical image such as an image, a figure, or a character by the action of an electron beam, and is classified into industrial and civil use according to its purpose. Industrial applications include oscilloscopes for electrical phenomena and waveform observation, frequency analyzers, and medical monitors. Commercial vehicles include CRTs and computer monitors.

On the other hand, an electron gun is a heat generated from a heater according to an externally applied voltage, that is, an electric signal for displaying image information, and thermal electrons of a cathode are emitted to control, accelerate, and focus the electrode to fluoresce the electron beam. An apparatus for creating an image by impinging on a film, which is inserted into and attached to the neck portion of a funnel. In general, a color cathode ray tube for a shadow mask is composed of three elements because it is necessary to independently stimulate three primary color phosphor pixels.

Hereinafter, with reference to the drawings will be described in more detail.

1 is a cross-sectional view showing a schematic configuration of a conventional color cathode ray tube. As shown, the color cathode ray tube can be largely divided into the CRT 100 and the deflection yoke 7. The CRT 100 has a fluorescent surface 6, which is coated with red, green, and blue phosphors on the front inner surface. A panel 3b to which the shadow mask 2 serving as a sorting function is connected, and a funnel 3c coupled to the side and having a tubular neck portion 3a formed rearward. Inside the neck portion 3a of the funnel 3c, an electron gun 5 for emitting an electron beam is embedded, and a deflection yoke for deflecting the electron beam 4 emitted from the electron gun 5 in a horizontal or vertical direction. (7) is combined.

It is sectional drawing which shows the structure of the conventional electron gun for color cathode ray tubes. As shown, the conventional electron gun 5 for the cathode ray tube is largely divided into three parts: the triode, the shear focusing lens, and the main lens. The three-pole portion includes a cathode 11 arranged in-line with a heater 10 embedded therein, and a control electrode 12 and an acceleration electrode 130 for controlling and accelerating hot electrons radiated from the cathode, respectively. It consists of a focusing electrode 141 and an anode 15 for focusing and finally accelerating the generated electron beam 9.

A shear focusing lens is formed between the triode and the main lens. The shear focusing lens is formed by inserting a plate-shaped electrode between the focusing lenses 140 and 141 in the drawing and applying a voltage equal to the accelerating electrode voltage to the electrodes, thereby accelerating the voltage with the focusing electrodes 140 and 141. A very strong shear focusing lens is formed between the second acceleration electrodes 131 to which the same voltage as that of the electrode 130 is applied.

Here, referring to the voltage applied to each electrode, a high voltage of 0 V is applied to the control electrode 12, 500 to 1000 V to the acceleration electrodes 130 and 131, 25 to 35 KV to the anode 15, and to the focus electrodes 140 and 141. An intermediate voltage of 20-30% of the anode voltage is applied.

In the conventional color cathode ray tube electron gun configured as described above (see FIG. 2A), a predetermined potential is applied to each electrode, in particular, as the electrostatic lens is formed by the voltage difference between the focusing electrode 141 and the anode 15. The electron beam 4 generated at is focused on the center of the fluorescent surface. At this time, the deflection yoke attached to the funnel 3c acts to deflect the electron beam focused at the center of the fluorescent screen to the entire area of the screen. In a color cathode ray tube using an in-line electron gun, red and green are usually used. Since the three electron beams of blue are arranged side by side horizontally, the deflection yoke 7 applies a self-convergence using a non-uniform magnetic field to converge the three electron beams in one place of the fluorescent surface.

Although the distribution of the magnetic field generated in the deflection yoke 7 to which the self-concentration type is applied is not shown, the horizontal deflection magnetic field is a pincushion type, and the vertical deflection magnetic field is a barrel type, so that the deviation in concentration on the fluorescent surface is reduced. (Mis-Convergence) is prevented. On the other hand, the magnetic field can be described by dividing into two-pole component and four-pole component, the two-pole component serves to deflect the electron beam in the horizontal and vertical direction, the four-pole component focuses the electron beam in the vertical direction and horizontal direction By dissipating, astigmatism is generated to distort the electron beam pixel spot.

Even if the magnetic field is close to uniform, the electron beam is subjected to significant astigmatism at the periphery of the fluorescent surface due to the fine pincushion or barrel magnetic component, which distorts the beam pixel (see FIG. 1B). More specifically, since the deflection magnetic field is not applied at the center of the screen, the electron beam spot has an accurate shape (see 4a of FIG. 1), but at the periphery thereof, as described above, the beam diverges in the horizontal direction and is over-focused in the vertical direction and distorted. The high density of the horizontal core and the high density haze (Haze (see FIG. 4B of FIG. 1)) are generated above and below, resulting in a decrease in resolution, especially at the periphery of the screen. This problem becomes larger the larger the water pipe and the larger the deflection angle.

The above-mentioned peripheral spreading phenomenon occurs because the deflection aberration receives a lot of deflection aberration at the center of the deflection yoke, and the horizontal direction from the deflection center cancels the divergence of the deflection magnetic field and the focusing force due to the distance difference, so that the electron beam is almost exactly However, in the vertical direction, the focusing force and the focusing force due to the distance difference overlap each other due to deflection aberration, so that many hazes are generated (see 4b in FIG. 1), so that the electron beam is adjusted at the three poles in order to reduce haze at the periphery. I need to do it.

In order to solve such a problem, the conventional electron gun has formed a slot around the hole of the control electrode 12, as shown in FIG. The shape of the control electrode hole has a horizontal shape which is mainly larger than the vertical shape of the control electrode hole, and an asymmetrical longitudinal slot is formed around the horizontal electron beam through hole with respect to the center of the through hole. The thickness of the slot of the control electrode is about 50% of the total thickness. In fact, as shown in Figure 4a, the control electrode of the conventional electron gun is formed of the total thickness (T1) and the thickness around the hole (T11) and the thickness of the slot portion (T1-T11) is about 50% of the total thickness ((T1- T11) / T1 x 100).

In addition, as shown in FIG. 3B, a periphery slot is also formed in the acceleration electrode 13. Although not shown, the pore diameter of the accelerating electrode 13 has a circular or square shape. In more detail, the total thickness T2 is about 0.37 mm, the slot depth T2-T22 is about 0.15 mm, and the slot depth is about 40% of the thickness of the entire acceleration electrode 13.

In this case, since the conventional electron gun has a strong shear focusing lens formed by the second acceleration electrode 131, the focusing force of the electron beam should be increased at the three poles. Otherwise, since the electron beam diameter before the incident to the main lens through the strong shear focusing lens is reduced, the phenomenon that the size of the pixel increases due to the increase in the space charge repulsion effect. 5 illustrates this phenomenon.

As shown in FIG. 5A, assuming that the beam diameter incident on the main lens is D1, D1 is determined by θ ₁ and θ ₂ . Since θ ₂ forms a strong focusing lens, in the absence of θ ₂ , the beam diameter D1 formed by θ ₁ increases in size due to spherical aberration due to the larger beam diameter than without the front focusing lens. This happens. Therefore, the beam diameter in the main lens should be determined to be equal to D1 even if θ ₂ is absent.

On the other hand, in general, the size Ds of the final pixel on the screen is defined as Dx when the magnification of the main lens is Dx, the spherical aberration is Dsa, and the electron beam magnification component due to the space charge repulsion effect is Dsc.

As a result, the main lens bimgyeong (D1) is a beam wonder is configured If disadvantages and small spherical aberration is due to space charge repulsion effects, so the pixel is larger, the same diameter or the main lens beam if no or if the θ ₂ if it grows Should be.

As described above, in the case of the conventional strong shear focusing lens, the acceleration electrode thickness must be 70% or less of the pore diameter in order to construct the optimum electron beam diameter D1, as shown in the prior art configuration. In this case, it is about 67%. If this is reduced, the beam diameter of the main lens is reduced to cause a space charge repulsion effect, thereby increasing the size of the pixel and consequently lowering the resolution.

However, there are various problems when using the strong shear focusing lens as described above. In more detail, the shear focusing lens is so strong that tolerance management is absolutely necessary. When the management is not performed properly, the path shift occurs, which causes the pixels to be disproportionately changed, and at the same time, the second acceleration electrode 131 and the first focusing electrode 140 must be additionally applied. It is disadvantageous on the side.

On the other hand, there is an ART effect as a method for solving the above problems. As shown in FIG. 6, the Abberation Reducing Triode (ART) effect is a technique related to the structural design of a triode that reduces aberration, and the paraxial electron beam enters the inside of the main lens and the outer electron beam is radiated outward of the main lens. As a method for reducing pixels on the screen, the above-described problem is solved by reducing the gap between the acceleration electrode and the focusing electrode and reducing the size of the pore diameter φG3 of the focusing electrode. 6A and 6B show the effects of the conventional electron beam structure, and FIGS. 6A and 6B show the ART effect.

Therefore, in order to enhance the ART effect, that is, in order to enhance the focusing force between the acceleration electrode G2 and the focusing electrode G3, the size of the hole of the focusing electrode G3 is mainly φ1.5 mm. The hole of is reduced to about 0.9 mm and the acceleration and focusing electrodes G2-G3 are reduced from 1.0 mm to 0.7 to 0.8 mm, and as shown in FIG. 7, the control electrode G1 and the acceleration electrode ( The characteristic to be solved was achieved by increasing the angle of the slot of G2). In particular, the pore size of the control electrode G1 is applied to the horizontal shape of the horizontal shape, that is, the shape of the hole (Hole) is large and vertical, and the slot angle of the control electrode G1 is 70 ° or more. Characterized in that configured to.

However, in the conventional method, the breakdown voltage characteristic is deteriorated because the G2-G3 between the acceleration electrode and the focusing electrode is small. The so-called discharge phenomenon generates a residual image of spark or leakage on the screen between a low voltage (acceleration voltage) and a high voltage (connection voltage) to cause a fatal defect of a water pipe. In order to improve this, reducing the gap between the acceleration electrode and the focusing electrode G2-G3 and reducing the pore size of the focusing electrode G3 is difficult to apply easily.

The present invention provides a color cathode ray tube having an electrode to which a control voltage and an acceleration voltage are applied, wherein the acceleration electrode has a thickness of 80% or more of the horizontal or vertical size of the acceleration electrode hole, and is centered on the electron beam passing hole of the electrode. By forming an asymmetric lens to increase the focusing force and to reduce the deflection aberration at the center of the deflection, slots are formed around the control electrode hole and the acceleration electrode hole to reduce the size of the electron beam pixel. In order to reduce the resolution and to improve the resolution of the screen peripheral portion, in particular, by processing the slot or about 30% of the thickness of the accelerating electrode.

According to an embodiment of the present invention for achieving the above object, a three-pole portion consisting of a plurality of electron emitting means for emitting an electron beam and a control electrode and an acceleration electrode for adjusting and controlling the radiation amount of the electron beam, respectively, and screen the electron beam And a plurality of focusing and accelerating electrodes forming an electrostatic focusing lens for focusing on the plurality of electron emitting means, wherein the plurality of electron emitting means and the plurality of electrodes are spaced apart from each other at a predetermined interval and sequentially arranged in the tube axis direction. The method may include forming a slot around the electron beam through hole of the acceleration electrode G2 and forming an electrode thickness of 80% or more of the horizontal or vertical size of the electron beam through hole.

Hereinafter, with reference to the drawings will be described in more detail.

As shown in FIG. 2B, the electron gun for the color cathode ray tube is formed of the control electrode 12, the acceleration electrode 13, the focusing electrode 14, and the anode electrode 15, and the same main lens beam diameter (FIG. In order to maintain D1) of 5b, it was formed to have a strong focusing force between the acceleration electrode 13 and the focusing electrode 14.

Looking at the configuration of the present invention in more detail, as shown in Figure 3, the control electrode 12 and the acceleration electrode 13 in the same manner as in the prior art each of the longitudinal slots and horizontal slots on the opposite electrode surface Have

In the case of the control electrode, as illustrated in the right side of FIGS. 4A and 4B, the thickness of the slot of the control electrode 12 is about 70% ((T 10 -T 100) / T 10 × 100) of the total thickness.

In addition, as shown in FIG. 3B, the acceleration electrode 13 has a slot around the periphery. Although not shown, the pore diameter of the acceleration electrode 13 is in the form of a circle or a square. The total thickness (T20) is about 0.75mm, the slot depth (T20-T200) is 0.2mm level and the depth of the slot is composed of about 30% or less of the total thickness of the acceleration electrode. The acceleration electrode 13 has a thickness of about 80% or more of the horizontal or vertical size of the pore size of the acceleration electrode 13, and the pore size of the focusing electrode is formed of 170% or more of the acceleration electrode.

In particular, the hole size of the acceleration electrodes 13 and G2 is formed to have a size of 105% or more and a vertical size of 120% or more of the horizontal size of the control electrodes 12 and G1.

On the other hand, the inventors form the beam diameter D1 of the main lens in the same manner as before (see FIG. 5) even if the shear focusing lens is deleted, while experimenting for the most effective design to strengthen the lens between the acceleration electrode and the focusing electrode. Was carried out.

FIG. 8 is a graph showing beam diameters that change as the pore size and thickness of the acceleration electrode 13 increase. In this case, as indicated by M1, M2, and M3 of FIG. 8, it can be seen that the electron beam size does not become smaller at any given point as the electron beam through hole and thickness of the acceleration electrode are increased. The reason can be explained through the following FIG. 9.

9 is a view showing a path of an electron beam that changes as the thickness of the acceleration electrode 13 and the pore diameter of the focusing electrode of the electron gun for a color cathode ray tube according to the present invention are increased. As shown in FIG. 9, when the thickness of the accelerating electrode is increased in thickness (see FIG. 9B), the outer electron beam enters the paraxial axis of the electron beam, and when the thickness is further increased (see FIG. 9C), the outer electron beam Is again crossed on the paraxial axis and falls out of the main lens. Accordingly, it can be seen that as the thickness is changed, the electron beam of the main lens is minimized at a certain point (M1, M2, M3).

As described above, the optimum main lens diameter may vary depending on the size or use of the screen, but most are optimized at 3.0 mm.

On the other hand, when the main lens diameter is based on 3.0mm, it can be seen that the larger the pore size of the acceleration electrode is, the smaller the difference between the point where the electron beam in the main lens becomes the minimum and the point having the optimum electron beam diameter becomes smaller. (L1, L2, L3 in FIG. 8). In other words, as shown in FIG. 8, when the acceleration electrode pore G2Φ is 0.5 mm and has a length L1, when the acceleration electrode pore G2Φ is 0.7 mm, the outermost electron beam has L3 smaller than L1. We can see that it is coming into this paraxial more. In other words, the larger the acceleration voltage pore G2Φ, the stronger the ART effect. Therefore, the larger the pore size of the acceleration electrode, the stronger the focusing lens formed between the acceleration electrode and the focusing electrode.

In the related art, although the ART effect was achieved by reducing the size of the pore of the focusing electrode in the electron gun and reducing the distance between the acceleration electrode and the focusing electrode, problems such as discharge phenomenon could not be solved, but according to the present invention, the pore size of the focusing electrode was increased. It can be seen that the same characteristics can be achieved even by increasing the distance between the acceleration electrode and the focusing electrode.

Therefore, in the present invention, the pore size of the focusing electrode could be increased from 0.9 mm to 1.2 mm, and the distance between the acceleration electrode and the focusing electrode could be increased from 0.7 to 0.8 mm to 1.0 mm. The pore size of the focusing electrode can be applied to the level of 1.5mm.

Next, the relationship between the slot of the control electrode, the acceleration electrode, and the pixel was examined.

First, the horizontal size of the pixel was examined.

FIG. 10 is a graph showing the relationship between the vertical pore diameter G1V of the control electrode, the slot depth G1D of the control electrode, the slot depth G2D of the acceleration electrode, and the horizontal size of the pixel, respectively. As shown in the graph form, the relationship between the factors G1V, G1D, and G2D and the horizontal size of the pixel can be known using the graph form, and the sensitivity of the relationship can be known through the slope. In more detail, as the vertical pore diameter G1V of the control electrode, the slot depth G1D of the control electrode, and the slot depth G2D of the acceleration electrode become larger, the horizontal size of the pixel decreases. It can be seen that the slot depth G1D of the control electrode is the largest.

Looking at the size of the vertical pixel, it tends to be the opposite of the size of the horizontal pixel.

FIG. 11 is a graph showing the relationship between the vertical pore G1V of the control electrode, the slot depth G1D of the control electrode, the slot depth G2D of the acceleration electrode, and the vertical size of the pixel, respectively. As shown in the graph form, the relationship between the factors G1V, G1D, and G2D and the vertical size of the pixel can be known using the graph form, and the sensitivity of the relationship can be known through the slope. In more detail, as the vertical pore diameter G1V of the control electrode, the slot depth G1D of the control electrode, and the slot depth G2D of the acceleration electrode become larger, the vertical size of the pixel increases. It can be seen that the slot depth G1D of the control electrode is the largest.

On the other hand, in general, when the pixel is viewed in the entire area of the screen, the vertical pixel is increased toward the periphery. That is, haze tends to occur especially in the vertical direction due to the distance difference from the neck of the neck to the center and the periphery of the screen and the influence of the self-convergence DY. Therefore, the haze tends to increase rapidly in the vertical direction of the pixel toward the periphery. In order to improve this, particularly, a structure in which the size of the pixel with respect to the focusing electrode voltage does not change in the vertical direction is required.

Next, the relationship between the focusing electrode voltage and the pixel will be described in more detail.

12 illustrates the relationship between the vertical pore diameter G1V of the control electrode, the slot depth G1D of the control electrode, the slot depth G2D of the acceleration electrode, and the sensitivity to the increase of the pixel according to the voltage of the focusing electrode. Figure is a graph. As shown in the graph form, the relationship between the respective factors G1V, G1D, and G2D and the sensitivity can be known, and the slope can also know the sensitivity of the relationship. In more detail, it can be seen that as the vertical pore size of the control electrode increases, the tracking increases, and as the slot depths of the control electrode and the acceleration electrode deepen, the tracking decreases.

The present invention aims to find a structure in which the horizontal size of the pixel is minimized and the vertical size is the same as that of a conventional electron gun, while the structure of the pixel is changed to a minimum with respect to the focusing electrode voltage. It was designed to be taken in the deep direction and the slot depth of the acceleration electrode was also in the deep direction, while the vertical pore size of the control electrode was reduced.

However, when such a structure is used, the penetration field due to the accelerating electrode voltage is weak due to the deep slot depth of the control electrode and the decrease in the control electrode pore size, thereby reducing the electron beam radiation area at the cathode, thereby reducing the cathode cut off. This results in a lower voltage. Therefore, the present invention is designed in a direction to reduce the thickness T100 of the control electrode.

In the case of the conventional electron gun, it is composed of the total thickness T1 of the control electrode and the thickness T11 of the free electrode, and the thickness of the slot portion T1-T11 is about 50% ((T1-T11) / T1 × 100). However, in the case of the present invention, by reducing the thickness (T11) around the ball and increasing the slot thickness (T1-T11), the thickness of the slot portion was composed of about 70% or more of the total thickness. In more detail, the free thickness of the control electrode was 0.07 mm, and the total thickness of the control electrode was 0.27 mm.

In the case of the accelerating electrode, the total thickness (T2) of the conventional electron gun is about 0.37 mm, the depth of the slot (T2-T22) is about 0.15 mm, and the slot depth is about 40% of the thickness of the entire accelerating electrode. The acceleration electrode of is characterized in that the slot depth in the deep direction to make the slot depth less than about 30% of the total thickness. In more detail, the entire thickness of the accelerating electrode was 0.75 mm, and the depth of the slot was 0.2 mm.

In addition, since the depth of the slot of the control electrode and the accelerating electrode is deepened to suppress the increase of the pixel with respect to the focusing electrode voltage, the vertical size of the pixel is increased, so that the vertical pore size of the control electrode is reduced. Therefore, the vertical size of the control electrode is smaller than the vertical size of the acceleration electrode, and the size of the pore size of the acceleration electrode relative to the control electrode is preferably 120% or more. In the case of the present invention, the vertical size of the control electrode is 0.5mm, the vertical size of the acceleration electrode was applied to about 0.7mm.

As described above, according to the present invention, the depth of the slot of the control electrode G1 is deepened and the depth of the slot of the acceleration electrode G2 is also deepened to reduce the horizontal size of the pixel for improving the resolution. The vertical size of is not increased significantly.

FIG. 13 is a graph showing the size of a pixel according to the related art and the present invention according to a focusing voltage, and illustrates the effects of the present invention described above. As shown in FIG. 13, in the most preferable case, the horizontal size of the pixel at the focusing voltage of 7800 V is 1.63 mm and the vertical size is 3.08 mm, whereas in the case of the conventional electron gun, the horizontal size is 2.85 mm and the vertical size is 3.41 mm. The size is reduced by about 40% compared to the conventional, the vertical size of the pixel is reduced by about 10% to improve the resolution. When the focusing voltage is + 400V, the change in the vertical size of the pixel of the conventional electron gun is increased by 0.8 mm, while the present invention exhibits an increase of 0.31 mm, which suppresses the increase in size by about 60% compared to the prior art, thereby increasing the focusing voltage. The halo of the periphery could be reduced.

According to the present invention, the thickness of the acceleration electrode of the color cathode ray tube having an electrode to which the control voltage (G1 voltage) and the acceleration voltage (G2 voltage) is applied has a thickness of 80% or more of the horizontal or vertical size of the acceleration electrode hole. By forming an asymmetric lens around the electron beam through hole of the electrode to increase the focusing force and to reduce the deflection aberration at the center of the deflection, to improve the peripheral resolution and to reduce the spot size, the control electrode G1 ) A slot is formed around the pore diameter and the accelerating electrode (G2), and the horizontal pixel size is reduced by processing a slot having a thickness of 70% or more of the control electrode thickness or 30% of the thickness of the accelerating electrode. The resolution can be improved by designing a desensitization of the pixel size according to the focusing electrode voltage in the vertical direction of the pixel.

As described above, the present invention has been described only with respect to the described embodiments, but can be designed in different directions according to the designer, and by configuring the depth of the slot of the control electrode and the depth of the slot of the acceleration electrode differently by the focusing voltage It may be configured differently in consideration of the amount of change in the size of the pixel and the horizontal verticalness of the pixel.

1 is a cross-sectional view showing a schematic configuration of a general color cathode ray tube.

It is sectional drawing which shows the structure of the conventional electron gun for color cathode ray tubes.

It is sectional drawing which shows the structure of the electron gun for color cathode ray tubes which concerns on this invention.

3A is a view showing an elongated slot formed around a control electrode hole of a conventional electron gun for color cathode ray tubes.

FIG. 3B is a view showing a horizontal slot formed around an acceleration electrode hole of a conventional electron gun for color cathode ray tubes.

4A is a view illustrating a comparison of a cross section of a control electrode according to the present invention with a cross section of a conventional control electrode.

4B is a view illustrating a cross section of a conventional acceleration electrode and a cross section of the acceleration electrode according to the present invention.

Fig. 5A is a diagram showing a beam diameter incident on the main lens in the conventional electron gun for color cathode ray tubes.

Fig. 5B is a diagram showing the beam diameter incident on the main lens in the electron gun for color cathode ray tube according to the present invention.

Fig. 6A shows the ART effect compared to the prior art.

FIG. 6B is a diagram illustrating ART effects compared to the prior art. FIG.

FIG. 7A is a diagram showing the path of the electron beam when the slot angle of the acceleration electrode is 45 °.

FIG. 7B is a diagram showing the path of the electron beam when the slew angle of the acceleration electrode is 70 °.

8 is a graph showing beam diameters that change as the pore size and thickness of the acceleration electrode increase.

9A is a view showing a path of a conventional electron beam for colored cathode ray tubes.

9B is a view showing a path of an electron beam that changes as the thickness of the acceleration electrode and the pore diameter of the focusing electrode of the electron gun for a color cathode ray tube are increased.

FIG. 9C is a diagram showing a path of an electron beam that changes as the thickness of the acceleration electrode and the pore diameter of the focusing electrode of the electron gun for a color cathode ray tube are increased.

FIG. 10 is a diagram illustrating a relationship between a vertical diameter G1V of a control electrode, a slot depth G1D of a control electrode, a slot depth G2D of an acceleration electrode, and a horizontal size of a pixel.

FIG. 11 is a diagram illustrating a relationship between a vertical pore G1V of a control electrode, a slot depth G1D of a control electrode, a slot depth G2D of an acceleration electrode, and a vertical size of a pixel.

FIG. 12 is a graph showing the relationship between the vertical pore diameter G1V of the control electrode, the slot depth G1D of the control electrode, and the slot depth G2D of the acceleration electrode and the tracking.

FIG. 13 is a graph illustrating the pixel sizes of the conventional and the present invention with respect to the focusing voltage. FIG.

*** Description of the symbols for the main parts of the drawings ***

2: shadow mask 12: control electrode

3a: neck portion 13: acceleration electrode

3b panel 14 focusing electrode

3c: funnel 15: anode

4a, 4b: electron beam 100: CRT

5: electron gun 130: acceleration electrode

6: fluorescent surface 131: second acceleration electrode

7: deflection yoke 140: focusing electrode

10: heater 141: focusing electrode

11: cathode

Claims (7)

A plurality of focusing and acceleration forming a three-pole portion consisting of a plurality of electron emitting means for emitting an electron beam, a control electrode and an acceleration electrode for adjusting and controlling the radiation amount of the electron beam and a electrostatic focusing lens for focusing the electron beam on the screen In the electron gun for a color cathode ray tube including an electrode, the plurality of electron emitting means and the plurality of electrodes are sequentially arranged in the tube axis direction spaced apart from each other, Among the electrodes forming the triode, slots are formed around the electron beam passing holes of the acceleration electrode G2, and the thickness of the acceleration electrodes is formed to be 80% or more of the horizontal or vertical size of the electron beam passing holes of the acceleration electrode. An electron gun for color cathode ray tubes. The method of claim 1, Electron gun for color cathode ray tube, characterized in that the depth (T20-T200) of the slot of the acceleration electrode (G2) is less than 30% of the total thickness (T20). The method of claim 1, The slot of the acceleration electrode (G2) is an electron gun for a color cathode ray tube, characterized in that formed in the direction of the control electrode. The method of claim 1, Electron gun for color cathode ray tube, characterized in that the slot is formed on the surface of the control electrode (G1) facing the acceleration electrode (G2). The method of claim 4, wherein Electron gun for color cathode ray tube, characterized in that the depth (T10-T100) of the slot of the control electrode (G1) is 70% or more of the thickness (T10) around the electron beam through-hole. The method of claim 1, The electron gun for a color cathode ray tube, characterized in that the ratio of the hole area of the focusing electrode (G3) and the hole area of the acceleration electrode (G2) is 1.7 or more. The method according to claim 2 or 5, Electron gun for color cathode ray tube, characterized in that the depth of the slot of the control electrode (G1) and the acceleration electrode (G2) is different.