KR100297697B1 - Electron gun for cathode ray tube - Google Patents

Abstract

Disclosed is an electron gun for a cathode ray tube. In the present invention, the size of the green electron beam through-holes formed in the center and the red and blue electron-beam through-holes formed on the left and right sides of the focus electrode forming the quadrupole lens are different from each other.

Description

Electron gun for cathode ray tube

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron gun, and more particularly, to an electron gun for a cathode ray tube in which the shape of three independent electron beam through holes for passing an electron beam is arranged inline.

In general, a cathode ray tube employs an inline electron gun that emits an electron beam so as to emit a phosphor by landing on a phosphor film applied to an inner surface of a panel. The electron gun has a triode consisting of a cathode, a control electrode, and a screen electrode, a plurality of focus electrodes provided to face the screen electrode to form a prefocus lens, and an anode to be formed to face the focus electrode to form a main focus lens. It consists of a wood electrode.

The electron gun determines the performance of the cathode ray tube according to the state in which the electron beam is landing on the phosphor. There has been a demand for the development of an electron gun that can reduce the focus characteristic and the aberration of the electron lens so as to accurately land the phosphor.

The electron beam emitted from the electron gun is deflected by the horizontal deflection magnetic field and the vertical deflection magnetic field formed by the deflection yoke provided at the neck portion of the cathode ray tube and landed on the phosphor.

That is, as shown in FIG. 1, the electron beam is distorted into a pin cushion phase distribution 11 by a horizontal deflection field and is distorted into a barrel phase distribution 12 by a vertical deflection field. As a result, the shape of the beam spot by the electron beam is distorted at the periphery of the screen forming the image, which causes a decrease in resolution.

In other words, while the center portion of the screen is not affected by the deflection magnetic field to maintain the shape of the circular beam spot 13, the deflection force for deflecting the electron beam horizontally is caused by the pincushion magnetic field 11 to vertically and vertically The deflection force for focusing and making the beam spot 14 pressed up and down, and deflecting the electron beam vertically diverges the electron beam horizontally and horizontally by the barrel magnetic field 12 to form a beam spot 15 that stretches from side to side. .

Therefore, the electron beam receives a focusing force in the vertical direction, and receives a diverging force in the horizontal direction, thereby generating a hollow 16 having a lower luminance toward the periphery.

In order to improve such a phenomenon, according to the prior art, a dynamic focus electron gun has been developed which varies the focal length of the electron beam while varying the shape of the electron beam in synchronization with the deflection current of the deflection yoke.

As shown in FIG. 2, in the electron gun employing the dynamic focus method, three independent electron beam through-holes 22 of the elongated type are formed on the emission side electrode 21 among the electrodes for focusing the electron beam, and the electrode 21 Three independent electron beam through-holes 24 are formed in the incident electrode 23 corresponding to the cross section.

As described above, the conventional electron gun has a structure in which the electron beam passing holes 22 and 24 of the electrodes 21 and 23 forming the quadrupole lens have a vertical or horizontal shape, and the electron beam passing holes 22 and 24. The size of) is the same as the green electron beam through hole formed in the center portion and the red and blue electron beam through hole formed on the left and right sides.

As a result, the dynamic voltage is reduced because the intensity of the electron lens in the red and blue electron beam through holes and the green electron beam through holes, that is, the magnification of the beam spots due to the electron beams landing at the periphery of the screen due to the different magnification occurs. The disadvantage is that you have to walk high.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has an object of providing an electron gun for a cathode ray tube which can reduce the dynamic focus voltage and improve the resolution of an image since the shape of the beam spot is not distorted at the periphery of the screen. .

1 is a graph showing the magnetic field distribution of a conventional electron gun,

2 is a perspective view showing a part of an electrode of a conventional electron gun,

3 is a sectional view schematically showing an electron gun according to the present invention;

4 is a perspective view showing a part of an electrode of the electron gun according to the first embodiment of the present invention;

5 is a perspective view showing a part of electrodes of the electron gun according to the second embodiment of the present invention;

6 is a perspective view showing a part of an electrode of an electron gun according to a third embodiment of the present invention;

7 is a perspective view showing a part of an electrode of an electron gun according to a fourth embodiment of the present invention.

<Brief description of symbols for the main parts of the drawings>

11. Pincushion magnetic field 12. Barrel magnetic field

21,23,41,43,51,53,61,63,71,73. electrode

22,24,42,44,52,54,62,64,72,74. Electron beam through hole

31. cathode 32. control electrode

33. Screen electrode 34. First focus electrode

35. Second Focus Electrode 36. Final Acceleration Electrode

55,75. Exterior enlargement unit

Electron gun for the cathode ray tube according to one aspect of the present invention to achieve the above object,

In a cathode ray tube electron gun comprising a cathode, a control electrode, a screen electrode, a plurality of focus electrodes forming a quadrupole lens, and a final acceleration electrode disposed adjacent to the focus electrode to form a main lens,

The red, green, and blue electron beam passing holes formed on the emission surface side of the focus electrode have a longitudinal shape, and the size of the red and blue electron beam passing holes formed on the left and right sides is larger than the size of the green electron beam passing holes formed in the center portion. It is characterized by.

According to another aspect of the present invention,

In a cathode ray tube electron gun comprising a cathode, a control electrode, a screen electrode, a plurality of focus electrodes forming a quadrupole lens, and a final acceleration electrode disposed adjacent to the focus electrode to form a main lens,

The red, green, and blue electron beam passing holes formed on the emission surface side of the focus electrode have a horizontal shape, and the size of the red and blue electron beam passing holes is larger than that of the green battery beam passing holes.

Hereinafter, an embodiment of a cathode ray tube electron gun according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Figure 3 illustrates one embodiment of a dynamic focus electron gun for a cathode ray tube according to the present invention.

As shown, the electron gun 30 is provided with a cathode 31, a control electrode 32, and a screen electrode 33 constituting the triode. In addition, the auxiliary lens and the quadrupole lens are formed to correspond to the first focus electrode 34, the second focus electrode 35, and the second focus electrode 35 in which the focus electrode is divided. It comprises a final acceleration electrode 36 to form a.

Here, an electron beam through hole, which is a means for forming a quadrupole lens, is formed on the emission side surface of the first focus electrode 34 and the incident side surface of the second focus electrode 35.

4 shows a first embodiment of the above-mentioned electrode.

Referring to the drawings, an elongated electron beam through hole 42 through which three electron beams pass is formed on the emission side of the first focus electrode 41, and a circular shape is formed on the incident side of the second focus electrode 43 corresponding thereto. An electron beam through hole 44 is formed. In this case, the horizontal electron beam through hole 42 is formed in a rectangular shape, and the red and blue electron beam through holes 42b and 42c on both sides are relatively larger than the green electron beam through hole 42a in the center portion.

The horizontal to vertical length ratios of the electron beam passing holes 42 are also different. That is, HR / VR, which is the ratio of the vertical length to the horizontal length of the red and blue electron beam through holes 42b and 42c, is smaller than HG / VG, which is the ratio of the vertical length to the horizontal length of the green electron beam through holes 42a. Relatively large. In this way, the through holes of the red and blue electron beam through holes 42b and 42c on both sides are larger than the green electron beam through holes 42a in the center part.

5 shows a second embodiment according to the present invention.

Referring to the drawing, three transverse electron beam through holes 52 through which three electron beams independently pass are formed on the emission side of the first focus electrode 51, and the second focus electrode 53 corresponding thereto is incident. Three electron beam through holes 54 are formed on the side surface.

The red and blue electron beam through holes 52b and 52c on both sides of the horizontal electron beam through hole 52 have a rectangular shape, and an outer surface enlarged part 55 having a key groove shape is formed at the center thereof. The green electron beam through hole 52a has a circular shape. Here, as mentioned in FIG. 4, the ratio of the vertical length to the horizontal length of the red and blue electron beam through holes 52b and 52c is relatively larger than that of the green electron beam through holes 52a.

Fig. 6 shows another electrode in the third embodiment of the present invention.

Referring to the drawings, three independent electron beam through holes 62 are arranged inline on the emission side of the first focus electrode 61, and three electron beams are also provided on the incident side of the corresponding second focus electrode 63. The through hole 64 is formed.

At this time, the electron beam through hole 62 is a rectangular shape of the longitudinal. Further, the red and blue electron beam through holes 62b and 62c are formed relatively larger than the green electron beam through holes 62a.

The vertical to horizontal length ratios of the electron beam passing holes 62 are also different.

That is, VR / HR, which is the ratio of the vertical length to the horizontal length of the red and blue electron beam passing holes 62b and 62c, is larger than VG / HG, which is the ratio of the vertical length to the horizontal length of the green electron beam passing holes 62a.

Fig. 7 shows another electrode in the fourth embodiment of the present invention.

Referring to the drawings, an elongated electron beam through hole 72 is formed on the emission side of the first focus electrode 71, and a circular electron beam through hole 74 is formed on the incident side of the second focus electrode 73. ) Is formed.

At this time, the red and blue electron beam passing holes 72b and 72c on both sides of the elongated electron beam passing holes 72 are formed with an outer surface enlarged portion 75 having a convex shape of a key groove, and green. The electron beam through hole 72a has a circular shape.

In the electron gun, of course, three focus electrodes forming the auxiliary lens and the quadrupole lens may be formed as necessary.

In the electron gun according to the present invention configured as described above, a parabola type dynamic focus voltage VFd is applied to the first focusing electrode and the second focusing electrode, and a high voltage anode voltage VE is applied to the final acceleration electrode. ) Is applied.

The application of the voltage to each of the electrodes is not limited to the above embodiment, and any configuration can be used as long as the electron beam can be concentrated by forming at least two quadrupole lenses.

In this case, the red and blue electron beam through holes are formed in the vertical or horizontal shape longer than the green electron beam through holes in the output side electrode of the first focus electrode, and the horizontal log vertical length ratio and the vertical log horizontal length ratio are relatively large. The beam spot caused by the electron beam passing through the blue electron beam through hole is greatly distorted than the beam spot passing through the green electron beam through hole.

Accordingly, the electron beam passing through the red and blue electron beam passing holes receives more deflection force by the pincushion or barrel magnetic field than the electron beam passing through the green electron beam passing hole, so that even if the distortion is severe, the electron beam passes in the distorted state in different directions. This makes it possible to obtain a circular beam spot.

As described above, the electrode for the cathode ray tube according to the present invention varies the size of the green electron beam through hole formed in the center portion of the electron beam through hole forming the quadrupole lens and the red and blue electron beam through holes formed on the left and right sides, and the horizontal length versus the vertical length. By varying the ratios, the intensity of the electron lens is enhanced at the electron beam passing holes of red and blue. Therefore, the dynamic focus voltage can be lowered, and the distortion caused by the deflection magnetic field due to the deflection of the electron beam can be reduced, so that a uniform cross section of the electron beam can be formed on the entire fluorescent surface.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (4)

In a cathode ray tube electron gun comprising a cathode, a control electrode, a screen electrode, a plurality of focus electrodes forming a quadrupole lens, and a final acceleration electrode disposed adjacent to the focus electrode to form a main lens, The red, green, and blue electron beam passing holes formed on the emission surface side of the focus electrode have a longitudinal shape, and the size of the red and blue electron beam passing holes formed on the left and right sides is larger than the size of the green electron beam passing holes formed in the center portion. Electron gun for cathode ray tube, characterized in that. The method of claim 1, The vertical length-to-horizontal length ratio of the red and blue electron beam passing holes is relatively larger than the vertical length to horizontal length ratio of the green electron beam passing holes. In a cathode ray tube electron gun comprising a cathode, a control electrode, a screen electrode, a plurality of focus electrodes forming a quadrupole lens, and a final acceleration electrode disposed adjacent to the focus electrode to form a main lens, The red, green, and blue electron beam passing holes formed on the emission surface side of the focus electrode have a horizontal shape, and the size of the red and blue electron beam passing holes is larger than that of the green battery beam passing holes. Electron gun. The method of claim 3, The horizontal length-to-vertical length ratio of the red and blue electron beam passing holes is relatively larger than the horizontal length-to-vertical length ratio of the green electron beam passing holes.