KR20000038861A - Electric gun for color cathode ray tube - Google Patents

Abstract

PURPOSE: An electric gun for a color cathode ray tube is provided to improve the productivity and the yield rate by improving the shape of the outside electric beam passing hole. CONSTITUTION: An electric gun for a color cathode ray tube comprises a plurality of cathodes which radiate an electric beam and a plurality of electrodes which controls, accelerates, and collects the electric beam. A fixing voltage is applied to one of the electrodes to form a fixing voltage collecting electrode. A variable voltage collecting electrode is formed by applying a variable voltage. According to the electric gun for a color cathode ray tube, the productivity and the yield rate is improved by improving the shape of the outside electric beam passing hole.

Description

Electron gun for colored cathode ray tube

The present invention relates to an electron gun for a color cathode ray tube, and more particularly, to improve convergence at the periphery of a screen in a high-resolution electron gun having one or more electrodes to which voltage is applied in synchronization with a deflection yoke. It was made to be possible.

Each electrode of the in-line electron gun for color cathode ray tubes is spaced perpendicular to the path through which the electron beam passes so that the electron beam generated at the cathode can be controlled in a constant intensity to reach the screen. Are arranged.

1 is an exemplary view showing a configuration of a general color cathode ray tube, in which an electron gun is three independent cathodes 1 and a first grid electrode disposed to be spaced apart from the cathode by a predetermined distance to serve as a common grid of three cathodes ( 2) and a second grid electrode 3, a third grid electrode 4 and a fourth grid electrode which are sequentially spaced apart from the first grid electrode to control and accelerate the thermal electrons radiated from the cathode. 5), a first acceleration and focusing electrode 6 for accelerating and focusing the electron beam emitted through the fourth grid electrode, and a second acceleration and focusing electrode 7 and the like.

The first acceleration and focusing electrode includes a lower electrode 6a to which a voltage is periodically changed in synchronization with the deflection yoke 14, an upper electrode 6b to which a constant voltage is always applied, and a correction electrode located in the upper electrode ( 8), and a correction electrode 8 is also provided inside the second acceleration and focusing electrode 7.

In addition, there is a shield cup 9 for shielding the deflection leakage magnetic field in front of the second acceleration and focusing electrode 7, and an astigmatism correcting electrode 10 between the second acceleration and focusing electrode 7 and the shield cup 9. ) Is installed.

Therefore, electrons are emitted from the cathode by the heat of a heater (not shown) installed inside the cathode 1, and the emitted electrons are controlled by the first grid electrode 2, which is a control electrode, and the controlled electron beam is Accelerated by the second grid electrode 3 which is an acceleration electrode.

As described above, the electron beams 11 and 12 and 13 accelerated by the second grid electrode 3 are composed of the third grid electrode 4, the fourth grid electrode 5, the first acceleration and Preliminary focusing is performed while passing through the lower electrode 6a of the focusing electrode, focused while passing through the second acceleration and focusing electrode 7, and then passed through a shadow mask 15 provided on the inner surface of the fluorescent screen 16 to form a fluorescent screen 16. A spot is formed at).

Each electron beam is focused on the screen between the first acceleration and focus electrode 6 and the second acceleration and focus electrode 7 to which a voltage that is periodically varied in synchronization with the deflection yoke 14 is applied. A focusing main lens is formed, and the main lens also focuses the R, G, and B electron beams at one point on the screen.

On the other hand, the focusing actions on the central electron beam 12 and the outer electron beams 11, 13 passing through the asymmetric large-diameter main lens are not the same, and in particular, the focusing actions of the outer electron beams 11, 13 are mutually horizontal and vertical. It is different, the astigmatism correction electrode 10 provided between the second acceleration and focusing electrode 7 and the shield cup 9 serves to weaken the focusing action in the vertical direction of the electron beam.

A conventional general high resolution electron gun in which a voltage that is periodically varied in synchronization with the deflection yoke 14 is applied to the upper electrode 6b of the first acceleration and focusing electrode is the upper part of the first acceleration and focusing electrode by the voltage that is periodically varied. When the voltage applied to the electrode 6b falls, the potential difference between the second acceleration and the fixed voltage applied to the focusing electrode 7 becomes large, so that the concentration of each electron beam becomes stronger and the electron beam arrangement of B, G, R becomes R, In contrast, the potential difference between the first acceleration and the voltage applied to the focusing electrode 7 decreases, and the focusing of each electron beam is weakened, and the arrangement of the electron beams of B, G, and R is B, G, R further widens.

That is, when a voltage that is periodically variable in synchronization with the deflection yoke is applied to the electrodes constituting the main lens, the intensity of the main lens is periodically changed and the distance between the R and B electron beam spots is changed according to the position of the screen. In particular, there is a problem in that the resolution of the periphery of the screen is degraded due to the distance change between the same spots.

Therefore, in recent years, a type of electron gun constituting a quadrupole lens on the opposite surface between the lower electrode 6a and the upper electrode 6b of the first acceleration electrode has been developed, and this type of electron gun is applied with a fixed voltage as shown in FIG. 2A. A method of varying the center side distance R ₁ and the outer side distance R ₂ based on the pitch of the outer electron beam passing hole shape of the electrode to be used or passing the outer electron beam of the electrode to which a fixed voltage is applied as shown in FIG. 2B. A separate vertical blade electrode 17 is attached to the ball portion, and the shape of the vertical blade electrode is different from the center side distance D ₁ and the outer side distance D ₂ based on the pitch or the inner height L ₁ is different. By varying the inner and outer intensities of the 4-pole lens in the horizontal direction by varying the outer height L ₂ , the distance between spots according to the change of the main lens is made by causing the outer and outer electron beams, R and B, to be bent properly. To effectively compensate for change Has the advantage.

However, in the conventional electron gun constituting the four-pole lens as described above, in the case of changing the shape of the outer electron beam through hole as shown in Fig. 2a, it is difficult to fix the electrode to the jig at the correct pitch when assembling the electron gun. Deterioration of the focus quality is lowered and the resolution is reduced, and in the case of attaching a separate vertical blade electrode as shown in Figure 2b the number of parts is increased, as well as the process is increased by welding the vertical blade electrode There are disadvantages.

An object of the present invention is to provide a simple structure of the electrode of the quadrupole lens to effectively compensate for the movement phenomenon of the screen spot by the main lens without increasing the parts or processes while the assembly characteristics are advantageous.

According to an embodiment of the present invention for achieving the above object is composed of a plurality of cathodes for emitting an electron beam and a plurality of electrodes for controlling, accelerating and focusing the electron beam, a fixed voltage to at least one of the plurality of focusing electrodes An electron gun for a color cathode ray tube, wherein a fixed voltage focusing electrode is formed by applying a variable voltage and a variable voltage focusing electrode is applied to at least one of the remaining focusing electrodes in synchronization with a deflection yoke. Alternatively, an inclined surface is formed in the outer electron beam through hole of the variable voltage focusing electrode so that the inner thickness and the outer thickness of the outer electron beam through hole are different, or a circular step is formed in the outer electron beam through hole, and the electron gun pitch of the outer electron beam through hole is formed. The width up to the center step and the width up to the outside step are There is provided an electron gun for a colored cathode ray tube formed differently.

1 is an exemplary view showing a configuration of a color cathode ray tube;

2A and 2B are low potential side shape views of a quadrupole lens component electrode applied to a conventional electron gun for color cathode ray tubes;

3 is a configuration diagram showing a concentration state of an electron beam by an electron gun for a color cathode ray tube of the present invention in comparison with the related art

4 is an enlarged view of a portion A of FIG. 3;

5A, 5B and 5C are front and cross-sectional views showing an embodiment of a four-pole lens configuration electrode applied to the electron gun for color cathode ray tube according to the present invention.

Explanation of symbols for main parts of the drawings

6a: lower electrode of the first acceleration and focusing electrode

6b: upper electrode of the first acceleration and focusing electrode

18: round step

3 is a configuration diagram of an electron gun for a color cathode ray tube according to the present invention, wherein the three cathodes 1, the first grid electrode 2, the second grid electrode 3, the third grid electrode 4, and the third independent grid electrode are independent of each other. A first acceleration and focusing electrode 6 consisting of a four grid electrode 5, a lower electrode 6a and an upper electrode 6b, a second acceleration and focusing electrode 7, a shield cup 9 and correction The basic arrangement of the electrodes 8, 10 and the like is the same as the conventional electron gun.

An electron beam through hole is formed in an electrode surface constituting an opposing surface of the lower electrode 6a and the upper electrode 6b of the first acceleration and focus electrode 6, and the inner and outer thicknesses of the electron beam through hole are It is formed differently.

5 is an embodiment in which the inner thickness and the outer thickness of the electron beam through hole are formed differently as described above. In the embodiment of FIG. 5A, the inner thickness of the electron beam through hole is inclined by inclining the outer and inner sides of the outer electron beam through hole. Ti) and the outer thickness To were different from each other, and in the embodiment of FIG. 5B, the step 17 was formed in the outer electron beam through hole to determine the inner thickness Ti and the outer thickness To of the electron beam through hole. Differently.

5A and 5B illustrate an example in which the inner thickness Ti of the outer electron beam passing hole is formed to be thinner than the outer thickness To, and the electrode having such a shape faces the focusing electrode to which the variable voltage is applied. It is applied to a fixed voltage focusing electrode which is an electrode.

FIG. 4 is an exemplary view in which the electrode shape shown in FIG. 5A is applied to the lower electrode 6a, which is a fixed voltage focusing electrode, and a warping phenomenon α occurs in which the outer electron beam is bent toward the center by an inclination formed on the lower electrode. The bending phenomenon makes it possible to compensate for the movement of the screen spot by the main lens.

In contrast to the above, when the present invention is applied to a variable voltage focusing electrode (upper electrode in FIG. 3) facing an electrode to which a fixed voltage is applied, the inner thickness Ti of the outer electron beam through hole of the upper electrode is outside. It should be formed thicker than the thickness To, and in this case, it is also possible to generate warpage in the outer electron beam by the upper electrode.

That is, when the electrode shape according to the present invention is applied to the fixed voltage focusing electrode, it becomes To> Ti, and when it is applied to the variable voltage focusing electrode, To <Ti is used to compensate for the movement of the spot by the main lens. It becomes possible.

Figure 5c is another embodiment showing the shape of the electrode according to the present invention, a circular stepped 18 having a diameter larger than the electron beam through hole around the outer electron beam through hole is formed, the outer electron beam through hole The width d ₁ to the center step of the electrode and the width d ₂ to the step of the outer direction are formed differently based on the pitch.

That is, the outer electron beam passing hole and the circular step 18 do not form concentric circles.

In the embodiment of Fig 5c for example it is possible when applying a fixed voltage focusing electrode d _1> d ₂ must be outside the electron beam can be deflected toward the center compensate for the movement of the spot by the main lens.

The electron gun for the cathode ray tube according to the present invention has a simple structure that forms an inclined surface or a jaw on the electrode of the quadrupole lens to compensate for the movement of the screen spot caused by the main lens. Compared to the electron gun, the assembly accuracy and focus quality can be improved. Compared to the electron gun using a separate vertical blade electrode, the number of parts is reduced and the welding process is excluded, resulting in cost reduction and productivity improvement.

Claims (8)

It consists of a plurality of cathodes for emitting an electron beam and a plurality of electrodes for controlling, accelerating and focusing the electron beam, by applying a fixed voltage to at least one of the plurality of focusing electrodes to form a fixed voltage focusing electrode and the remaining focusing electrode An electron gun for a color cathode ray tube, wherein a variable voltage focusing electrode is formed by applying a variable voltage varying in synchronization with a deflection yoke to at least one of the electrodes, wherein the outer electron beam is formed on the surface of the fixed voltage focusing electrode facing the variable voltage focusing electrode. Electron gun for color cathode ray tube, characterized in that formed by forming the inner thickness (Ti) and the outer thickness (To) of the through hole differently. The electron gun for a color cathode ray tube according to claim 1, wherein an outer electron beam through hole of said fixed voltage focusing electrode has an inner thickness thinner than an outer thickness. It consists of a plurality of cathodes for emitting an electron beam and a plurality of electrodes for controlling, accelerating and focusing the electron beam, by applying a fixed voltage to at least one of the plurality of focusing electrodes to form a fixed voltage focusing electrode and the remaining focusing electrode An electron gun for a color cathode ray tube, in which a variable voltage focusing electrode is formed by applying a variable voltage that is changed in synchronization with a deflection yoke to at least one of the electrodes, the electrode gun of the variable voltage focusing electrode facing the fixed voltage focusing electrode. An electron gun for a color cathode ray tube, characterized in that the inner thickness (Ti) and the outer thickness (To) of the outer electron beam passing hole are formed differently. 4. The electron gun for color cathode ray tubes according to claim 3, wherein an inner thickness of the outer electron beam through hole of the variable voltage focusing electrode is formed thicker than an outer thickness. It consists of a plurality of cathodes for emitting an electron beam and a plurality of electrodes for controlling, accelerating and focusing the electron beam, by applying a fixed voltage to at least one of the plurality of focusing electrodes to form a fixed voltage focusing electrode and the remaining focusing electrode An electron gun for a color cathode ray tube, wherein a variable voltage focusing electrode is formed by applying a variable voltage varying in synchronization with a deflection yoke to at least one of the electrodes, wherein the electron beam passing hole is formed on the surface of the fixed voltage focusing electrode facing the variable voltage focusing electrode. A collar characterized in that a circular step of a larger diameter is formed and the width d ₁ to the center step is different from the width d ₂ to the step in the outer direction based on the electron gun pitch of the outer electron beam passing hole. Electron gun for cathode ray tube. 6. The electron gun for color cathode ray tubes according to claim 5, wherein a width d ₁ of the fixed voltage focusing electrode to a center step of the outer electron beam passing hole is wider than a width d ₂ of an outer step. It consists of a plurality of cathodes for emitting an electron beam and a plurality of electrodes for controlling, accelerating and focusing the electron beam, by applying a fixed voltage to at least one of the plurality of focusing electrodes to form a fixed voltage focusing electrode and the remaining focusing electrode An electron gun for a color cathode ray tube, wherein a variable voltage focusing electrode is formed by applying a variable voltage varying in synchronization with a deflection yoke to at least one of the electrodes, the outer electron beam passing hole formed on the surface of the variable voltage focusing electrode facing the fixed voltage focusing electrode. A collar characterized in that a circular step of a larger diameter is formed and the width d ₁ to the center step is different from the width d ₂ to the step in the outer direction based on the electron gun pitch of the outer electron beam passing hole. Electron gun for cathode ray tube. 8. The electron gun for color cathode ray tubes according to claim 7, wherein the width d ₁ of the variable voltage focusing electrode to the center step of the outer electron beam passage hole is smaller than the width d ₂ of the step of the outer direction.