KR900009081B1 - Electron gun of color display tube - Google Patents

Abstract

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Description

A water gun

Figure 1a is a diagram showing a horizontal cross section of the electron gun of one embodiment of the present invention.

Fig. 1B is a perspective view of the main part of Fig. 1A.

2 is a diagram showing a horizontal section of a color water pipe with a conventional electron gun.

FIG. 3 is a diagram showing an electron beam spot shape of each part of a screen of a color receiver by a conventional electron gun. FIG.

4A is a diagram showing a horizontal section of a conventional example of another electron gun.

4B is a perspective view of the main part of FIG. 4A.

5, 6 and 9 show the analysis results of the present invention and conventional electron gun characteristics.

7, 8, 10, 12, 13 and 14 show the electrode structure of another embodiment of the present invention.

Fig. 11 is a diagram showing an example of an applied potential waveform of an electron gun example according to the present invention.

15A is a horizontal cross-sectional view of an electron gun of another embodiment of the present invention.

Fig. 15B is a perspective view of the main part thereof.

Fig. 16 is a graph showing the measurement result of the electron gun characteristics of the embodiment according to the present invention.

17 is a front and vertical sectional view of an essential part of another embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

1: outside glass 2: face plate

3: fluorescent surface 4: shadow mask

5: conductive film 6, 7, 8: cathode

14 groove 16: external magnetic deflection yoke

17, 18, 19: central axis 31: high brightness portion (core)

32: low luminance part (halo) 81: horizontal slit

101a, 101b, 103a, 103b: groove portion

121, 121 ', 121 ", 121a, 121b: first member of the fourth electrode

122, 122 ', 122 ", 122a: second member of the fourth electrode

123, 123 ', 123 ", 123a, 123b: third member of the fourth electrode

The present invention relates to a water tube electron gun, and more particularly, to an electrode forming a main lens of an inline type color water tube electron gun.

2 is a plan view of a color water pipe equipped with a conventional electron gun. On the inner wall of the face plate portion 2 of the glass envelope 1, a fluorescent surface 3 having three phosphors applied alternately is supported. The central axes 17, 18, and 19 of the cathodes 6, 7, and 6, which generate electron beams, include the first electrode G1, the second electrode G2, and the main electrode. The center axis of the opening portion corresponding to the cathode having the third electrode G3, the fourth electrode G4, the fifth electrode G5, and the shielding cup 15 constituting the lens is coincident with each other. And these central axes 17, 18, and 19 are arrange | positioned substantially parallel on a common plane. The direction along this common plane is called a horizontal direction hereafter. Outer cylindrical axis 9 arranged in the outward direction among the cylindrical parts protruding from the opening hole of the sixth electrode G6 which is the final electrode constituting the main lens in the inward direction of the sixth electrode G6, ( 10 is eccentric outward with respect to the central axes 17, 19.

Three electron beams emitted from each of the cathodes 6, 7, and 8 enter the main lens along the central axes 17, 18, and 19, respectively. The central axes 17, 18, and 19 are referred to as the initial passages of the electron beam. In the embodiment of the present invention of FIG. 1, the main lens includes the third electrode G3, the fourth electrode G4, and the first lens. So-called bi-potential focusing formed by a so-called uni-Potential Focusing electron lens (UPF lens) formed by the fifth electrode G5 and the fifth electrode G5 and the sixth electrode G6 ( Bi-Potential Focusing It consists of a combination of two electron lenses of an electron lens (BPF lens). The sixth electrode G6 is made of the shielding cup 15, the conductive film 5 formed inside the glass atmosphere 1, and the coin phase, and a high voltage of about 20 to 30 KV is applied. A connection voltage of about 5 to 9 KV is applied to the third electrode G3 and the fifth electrode G5. A low potential of about 400 to 1000 V, which is about the same potential as that of the second electrode G2, is applied to the fourth electrode G4. The incident electron beam of the main lens is connected by the two electron lenses (UPF and BPF lens). Since the main lens is formed symmetrically with respect to the electron beam (center beam) incident along the center axis 18, the center beam is connected by the main lens, and then goes straight along the trajectory along the center axis 18.

On the other hand, in the BPF lens formed by the fifth electrode G5 and the sixth electrode G6 of the electron lenses constituting the main lens formed along the outer center axes 17 and 19, the sixth electrode ( Since the central axes 9 and 10 of G6 are outward, the electron beams pass inward of the central axis of the lens in the sixth electrode G6, and at the same time as the central axis 18 The electron beam trajectory is bent. In this way, the electron beam (external axis beam) incident on the main lens along the outer center axes 17 and 18 is focused by the main lens and at the same time in the center beam direction. As described above, the three electron beams are imaged on the shadow mask 4 and are concentrated to overlap each other. In this way, the operation of concentrating each electron beam is called convergence, and in particular, taking convergence at the center of the screen is called positive convergence (hereinafter referred to as STC). Each electron beam is color-selected by the shadow mask, and only components that excite and emit corresponding color phosphors reach the fluorescent surface through the openings of the shadow mask. In addition, in order to scan the electron beam onto the fluorescent surface, an external magnetic deflection yoke 16 is mounted on the periphery of the glass external atmosphere 1.

If the STC is taken at the center of the screen by combining an inline electron gun in which three electron beam paths are distributed on one horizontal plane, and a so-called self-convergence deflection yoke that forms a special non-uniform deflection field distribution, the whole screen area is different. It is known to take convergence over. In general, however, the self-convergence deflection yoke has a problem in that the resolution is reduced at the periphery of the screen due to the large deflection aberration due to the nonuniformity of the magnetic field. 3 schematically shows the shape of the electron beam spot deformed by deflection aberration.

In the periphery of the screen, the high luminance portion 31 (core) of the electron beam indicated by the diagonal lines is widened in the horizontal direction, and the low luminance portion 32 (halo) is widened in the vertical direction. In the screen nose owner portion, the residual beam spot is rotating.

Japanese Tokkai No. 61-74246 discloses a means to solve this problem. 4 shows an electron gun according to the conventional example. The fourth electrode G4 is divided into three parts from the cathodes 6, 7, and 8 into the first member 121, the second member 122, and the third member 123 toward the fluorescent surface. Low potentials that are substantially the same as the potentials of the second electrodes G2 are applied to the first and third members 121 and 123. The second member 122 is formed with a long slit-shaped opening 12 in the horizontal direction, and a potential, that is, a dynamic potential, is dynamically changed in synchronization with the deflection current supplied to the deflection yoke. When the deflection amount is large, the potential difference between the first, third members 121, 123 and the second member 122 becomes large, so that the strength of the non-axis-symmetric lens formed by the slit becomes strong, resulting in astigmatism in the electron beam spot. Occurs. If the potential of the second member 122 is higher than the potential of the first, third members 121, 123, the astigmatism generated in the electron beam extends the core in the vertical direction and stretches the halo in the horizontal direction. Since it is effective, the astigmatism can be canceled in accordance with the electron beam deflection shown in FIG. 3, so that the resolution around the screen can be improved.

On the other hand, when the electron beam is not deflected, there is no potential difference between the first and third members 121 and 123 and the second member 122 so that an asymmetrical lens is not formed so that astigmatism does not occur in the center of the screen. Since it can be set as a condition which does not, resolution deterioration does not occur.

In the above-described conventional example, only electrodes for canceling astigmatism are specified among the deflection aberrations, and therefore, consideration of an important top surface curvature as another deflection aberration is not considered. Because of this aberration, even if a condition in which the electron beam is focused at the center of the screen is given, the electron beam is focused at the peripheral portion before reaching the screen, which is greatly widened on the screen, and the resolution of the screen peripheral portion of the color CRT deteriorates.

Therefore, in the above-mentioned conventional example, it is necessary to add a dynamic potential generating circuit for astigmatism correction, and to provide a circuit for changing the focusing voltage dynamically to change the main lens intensity according to the electron beam deflection, thereby correcting image curvature. have. However, since this focusing voltage is a high voltage of 5-10KV, it is not easy to construct a circuit which changes the voltage dynamically for this top surface curvature correction.

SUMMARY OF THE INVENTION An object of the present invention is to provide an electron gun capable of simultaneously correcting astigmatism and surface curvature with a single circuit that generates a relatively low potential dynamic potential.

In order to correct the curvature of the upper surface, when the electron beam is deflected around the screen, the potential of the fourth electrode G4 is raised to be increased by the third, fourth, and fifth electrodes G3, G4, and G5. What is necessary is just to weaken the intensity of the UPF lens comprised. In performing astigmatism correction at the same time, the fourth electrode G4 is divided into first, second and third members, and a non-circular opening is formed in the second member, so that the first, third and second members The potential difference may be changed in synchronization with the deflection current.

At this time, the potential of the second member is made constant, and the potential of the first and third members is changed to a dynamic potential that changes according to the deflection current.

When the potential of the first and third members is fixed and the potential of the second member is raised as in the conventional example of FIG. 4, the effect of the potential rise is shielded by the first and third members. The amount of change in lens intensity between the fourth and fifth electrodes is small, and image curvature cannot be corrected effectively.

By forming a non-circular opening in the second member of the fourth electrode and changing the potential difference with the first and third members to synchronize with the deflection current, astigmatism due to deflection can be corrected. At this time, when the second member potential is fixed and the first and third member potentials are raised during deflection, the third electrode G3, the first member 121, the fifth electrode G5, and the third member are raised. Since the members directly face the members, the operation of weakening the lens strength, that is, the image curvature correction can be effectively performed.

Another object of the present invention is to provide an electron gun electrode structure which can realize astigmatism correction and dynamic focus at the same time with a circuit which generates a relatively low potential dynamic potential, and does not cause adverse effects on convergence at this time. .

In order to perform dynamic focus, when the electron beam is deflected to the periphery of the screen, the G4 potential is increased to weaken the UPF lens intensity constituted by the G3, G4, and G5 electrodes. When astigmatism correction is performed at the same time, the G4 electrode is divided into a first member 121, a second member 122, and a third member 123, and a non-circular opening (hole) is formed in the second member to form a first The potential difference with the third member may be changed in synchronization with the deflection current. At this time, a configuration in which the potential of the second member is made constant and the potential of the first and third members changes in accordance with the deflection current is effective for dynamic focus.

Moreover, in order to remove the bad influence on convergence, what is necessary is just to make the non-circular hole formed in a 2nd member into a long slit-shaped hole in a vertical direction. In such a configuration, when the electron beam deflection amount is large, increasing the dynamic potential of the first and third members weakens the main lens intensity, so that dynamic focus can be realized, and at the same time, the potential difference with the constant of the second member is constant. Since the astigmatism is enlarged to cancel the astigmatism due to the deflection, the astigmatism in the reverse direction can be increased.

By forming a non-circular opening in the second member 122 of the G4 electrode and changing the potential difference with the first and third members 121 and 123 to synchronize with the deflection current, astigmatism due to deflection can be corrected. have. At this time, when the potential of the first and third members is increased and the potential of the second member is lowered during deflection, the G3 electrode 11, the first member 121, the G5 electrode 13, and the third member are lowered. Since 123 faces directly, the lens strength can be weakly operated, that is, the dynamic focus can be effectively performed. On the other hand, when the potential of the first and third members is fixed and the potential of the second member is raised as in the conventional example of FIG. 4, the effect of the potential rise is the first and third members 121 and 123. ), The amount of change in lens intensity between the G3 to G5 electrodes is small, and dynamic focus cannot be effectively performed. Here, the operation method of making the potential of the second member 122 constant can also be considered. However, if the potential of the second member is lowered according to the amount of deflection, the astigmatism correction effect becomes stronger.

In addition, when the opening of the second member is a non-circular hole, and the slit-shaped openings formed in the vertical direction are not affected by the adjacent openings, the cone is formed as in the case of forming a long slit-shaped opening in the horizontal direction. Don't mess with Versus.

The present invention is effective even when applied to not only a color water pipe but also a single electron non-water pipe.

Hereinafter, an embodiment of the present invention will be described with reference to FIG. The high potential Eb of 20 to 30 KV is applied to the sixth electrode G6 through the shielding cup 15. An intermediate potential (concentration voltage… V _f ) of 5 to 10 KV is applied to the third electrode G3 and the fifth electrode G5. A low potential of 100 to 1500 V is applied to the fourth electrode 14 divided into three members 121, 122 ′, and 123. The UPF lens is formed by the third, fourth, and fifth electrodes G3, G4, and G5, and the BPF lens is formed by the fifth, sixth electrodes G5, and G6. The main lens is constituted by a combination of two electron lenses.

Long slits in the vertical direction are formed in the openings of the second member 122 'disposed at the center of the three members, and are held on the second electrode G2 and the coin. The same potential V _G4 is applied to the first and third members 121 and 123 disposed on both sides of the second member 122 ′. (V _G4 ) is the dynamic potential that changes in synchronization with the deflection current. When the deflection current is large and the electron beam deflection is large, the value of (V _G4 ) is increased to increase the strength of the axisymmetric lens formed in the slit, thereby canceling the astigmatism caused by the electron beam deflection.

5 is a result of analyzing the effect of the embodiment of FIG. 1 using a calculator.

The specific dimension of the main lens of the electron gun which analyzed was as follows.

Opening diameter of the third electrode G3 [second electrode G2 side] ø1.5

〃 [Fourth electrode (G4) side] ø4.0

Length of third electrode G3 2.7

Opening diameter ø4.0 of the first and third members 121 and 123 of the fourth electrode G4

〃 〃 Electrode length 0.5

Opening diameter (l ₁ ) of the second member 122 'of the fourth electrode G4 ø4.0

〃 〃 Slit opening diameter (ℓ ₂ ) ø6.0

〃 slit width (W) 3.0

〃 〃 electrode length 0.7

Diameter of Fifth Electrode G5 [Fourth Electrode G4] ø4.0

〃 〃 [sixth electrode (G6) side] ø8.0

Fifth electrode length 24.3

Opening diameter of the sixth electrode G6 ø8.0

(Unit: mm)

Further, the applied voltage Eb to the sixth electrode G6 is 25KV, and the applied voltage (same as the applied voltage to the second electrode G2) to the second member 122 'of the fourth electrode G4 is 650V. do. The distance between the shadow mask 4 and the end portion of the third electrode G3 side of the fourth electrode G4 is 340 mm, and the electron beam is focused on the shadow mask 4.

)의 값은 저하한다. 이것은 주렌즈강도가 약하게 되어 있는 것을 나타낸다. 따라서 (V_G4)를 상승시켰을때 (V_f)를 일정한 값으로 해놓으면, 전자비임이 집속되는 위치와 주렌즈사이의 거리가 연장되게 된다.The dynamic potential V _G4 applied to the first and third members 121 and 123 constituting the fourth electrode G4 is changed, and an electron beam is provided at the center of the screen with respect to the value of each V _G4 . third, the potential of the fifth electrode (V _f) the value (V _fh) and a third potential of the fifth electrode in the vertical direction halo reversed erased when (V _f) of the time the horizontal direction of the spot halo reversed erased _Obtain each value (V _fv ). When (V _G4 ) is 150 V from FIG. 5, the values of (V _fh ) and (V _fv ) are the same, and astigmatism does not occur in the electron beam, and (ΔV _f ) becomes zero. When the value of (V _G4 ) is increased, the astigmatism becomes stronger, and the voltage difference obtained by subtracting (V _fv ) from the astigmatism voltage ΔV _f , that is, (V _fh ) increases. At this time, the average value of (V _fh ), that is, the average value of the focused voltage (

) Decreases. This indicates that the main lens intensity is weak. Therefore, if (V _f ) is set to a constant value when (V _G4 ) is raised, the distance between the position where the electron beam is focused and the main lens is extended.

In order to correct the astigmatism due to the deflection, the value of V _G4 is increased when the electron beam is deflected to the periphery of the screen, and the astigmatism caused by the main lens is increased. The astigmatism caused by the main lens has an effect of expanding the halo in the horizontal direction and suppressing the halo in the vertical direction. On the other hand, astigmatism due to deflection has a function of strengthening the halo in the vertical direction, so that these astigmatisms can be canceled from each other. By increasing the value of (V _G4 ) according to the amount of deflection, astigmatism due to deflection can be corrected in each part on the screen.

At the same time, since the main lens intensity becomes weak due to the rise of (V _G4 ) and the electron beam focusing position extends in the screen direction, it is possible to match the screen position with the electron beam connection position which did not coincide due to the image curvature.

By raising the value of (V _G4 ) in accordance with the increase of the deflection amount in this way, it is possible to simultaneously correct the astigmatism and the image surface curvature caused by the electron beam deflection.

In addition, in the conventional example shown in FIG. 4, since the slit opening of the fourth electrode G4 is horizontally long, it is close to each other. Thus, the electron lens for both side electron beams is asymmetrical with respect to the vertical plane including the respective central axes 17, 19, and the outer electron beams are bent in the center beam direction, adversely affecting convergence. The problem arises. In the embodiment of FIG. 1, since the opening is formed vertically long, this problem can also be solved.

)와의 관계를 계산기 해석으로 구한 결과를 나타낸다. 이때, 전자총 주렌즈의 치수는 제5도의 해석에 사용한 치수와 동일하다. 단, 슬릿은 수평방향으로 형성되어 있으나, 슬릿치수는 결국 제5도의 해석조건과 동일하다. 제6도의 결과로부터 종래예에 나타낸 전자총에서는, (V'_G4)의 변화에 대한 (

)의 변동량이 작아 상면만곡보정효과가 거의 없는 것을 알 수 있다.6 shows the dynamic potential V ′ _G4 applied to the second member 122 of the fourth electrode G4 of the electron gun of the conventional example of FIG. 4, the astigmatism voltage ΔV _f , and the convergence voltage average value (

The result obtained by calculating the relationship with At this time, the dimension of the electron gun main lens is the same as the dimension used for the analysis of FIG. However, although the slit is formed in the horizontal direction, the slit dimension is the same as the analysis condition of FIG. In the electron gun shown in the conventional example from the result of FIG. 6, the change of ( _V'G4 )

It is understood that the amount of fluctuation of) is little and the top curvature correction effect is hardly obtained.

Therefore, in order to correct the top surface curvature, a configuration in which a signal synchronized with the deflection current is applied to the first, third members 121, 123 of the fourth electrode G4 as in the embodiment of FIG. And, as in the conventional example, the configuration applied to the second member 122 is inappropriate.

FIG. 7 shows that the first member 121 'and the third member 123' of the fourth electrode G4 are horizontally long in the opening in the surface facing the second member in order to more effectively perform astigmatism correction. This is an example in which the groove portion 71 is formed.

8 illustrates an embodiment in which the through slits 81 are elongated in the horizontal direction in the openings of the first member 121 "and the third member 123" of the fourth electrode G4. When the dynamic potential V _G4 applied to the first and third members 121 ″ and 123 ″ is higher than the potential of the second member 122 ″, the horizontal slits 81 are formed of the first and the third electrodes. There is an effect of changing the astigmatism voltage in the positive direction between the three members 121 ", 123 " and the second member 122 ', and (V _G4 ) is the third and fifth electrodes G3, Since it is lower than the potential V _{f of} (G5), the astigmatism voltage is negative between the third electrode G3 and the first member 121 ", and the fifth electrode G5 and the third member 123". When V _G4 rises, the astigmatism generated between the first and third members 121 ", 123" and the second member 122 'becomes stronger, and the third The astigmatism generated between the fifth electrodes G3 and G4 is weakened, and the effect of changing the astigmatism in the positive direction becomes stronger.

FIG. 9 shows an analysis result of the effect when the embodiment of FIG. 8 is used. The analysis of the electron gun main lens is performed in the analysis of FIG. 5 except that the horizontal slits 81 having the following dimensions are formed in the first and third members 121 "and 123". Same as the main lens dimension used.

Opening diameter of the slit member (l ₃ ) of the first and third members 121 "and 123" of the fourth electrode G4 ø4.1

〃 slit width (W) 2.0

(Unit: mm)

Electrode potential is also the same as the example used for the analysis of FIG.

Comparing the analysis result of FIG. 9 with the analysis result of FIG. 5, in FIG. 9, the potentials of the first and third members 121 ″ and 123 ″ are set to zero the astigmatism voltage ΔV _f . V ', and the value of _G4) is increased to 660V, the second member (122' it can be seen that substantially matches the potential of the). In the embodiment of FIG. 1, the second member 122 'and the third and fifth electrodes G3 and G5 are equal to each other even if the potential of the second member 122' and V ' _G4 coincide with each other. This is because the astigmatism can be caused by the astigmatism caused by the effect of the horizontal slits 81 in the embodiment of FIG. For this reason, in the embodiment of FIG. 8, the strength of the UPF lens formed by the third, fourth, and fifth electrodes G3, G4, and G5 is weakened compared with the embodiment of FIG. The lens can enlarge the electron beam diameter at the outlet. As a result, the electrons in the beam rebound from each other due to the coulomb force, that is, the space charge effect or the effect of the beam being widened due to the thermal hyperspeed in the non-radial direction of each electron, that is, the screen Expansion of the electron beam spot on the image is suppressed.

)의 변화량은 약 반으로 감소되어 있는 것을 알 수 있다. 이것은, 제4전극(G4)의 제1, 제3부재(121"), (123")의 슬릿을 여러가지형상으로 함으로써, 각종 편향코일의 수차특성에 맞추어서 비점수차와 상면만곡의 보정량을 독립적으로 조정할 수 있다는 것을 나타내고 있다.Also, comparing the analysis result of FIG. 9 with FIG. 5, the change amount of (ΔV _f ) with respect to the change of (V ′ _G4 ) is about the same,

It can be seen that the amount of change is reduced by about half. This allows the slits of the first, third members 121 ", and 123 " of the fourth electrode G4 to have various shapes to independently correct the astigmatism and the correction of the upper surface curvature in accordance with the aberration characteristics of the various deflection coils. It shows that it can adjust.

In the embodiment of FIG. 8, the slit 81 of the first and third members 121 ″ and 123 ″ is connected to the third and fifth electrodes G3 and G5, respectively. Are facing directly. Since the potential difference between the third and fifth electrodes G3 and G5 and the fourth electrode G4 is several KV, and the lens strength is strong, the slit dimension is very small compared to the slit of the second member 122 '. Even if it is made small, the effect obtained is large. Therefore, although the horizontal slit is formed, since the dimension is small, the adverse effect on the convergence characteristic does not occur as in the conventional example of FIG.

10A and 10B show the configuration of the fourth electrode G4 for correcting the rotation of the electron beam spot in the screen corner portion caused by the deflection. As in the example of FIG. 7, the grooves 101a and 103a are formed on the surface of the fourth electrode G4 where the first and third members 121a and 123a face the second member 122a. The central axes of the grooves 101a and 103a are inclined with respect to the horizontal plane. Therefore, the plane of symmetry of the electron lens formed in this portion is also inclined with respect to the horizontal plane. Since the inclination direction is opposite to each other in the first member 121a and the third member 123a, the inclination direction of each electron lens formed near each member is also reversed. Independent of the first member 121a and the third member 123a, the potentials V ' _G4 and V " _G4 changing in synchronization with the deflection current are common to the G2 electrode in the second member 122a. When a constant potential V _G2 is applied, when (V ' _G4 ) and (V " _G4 ) are larger than (V _G2 ), it has an effect which rotates an electron beam spot in the opposite direction to the inclination of each groove part. That is, in FIG. 10A, since the groove portion 101a of the first member 121a is rotated counterclockwise with respect to the plane as viewed from the cathode side, the electron beam spot is rotated clockwise. On the contrary, in the third member 123a of FIG. 10B, the electron beam spot is rotated counterclockwise.

The method of claim 11 degrees, a represents an example of a waveform of the first member (121a) potential (V _'G4) and the second member (123a) potential (V _"G4) of the respective solid lines and one-dot chain line. Constant potential ( V _G2 ) is indicated by a dashed line.

In the initial part of the vertical scanning period V, the electron beam spot is in the upper part of the screen, and in the initial part of the horizontal scanning period H, it comes in the upper-left nose holder part. At this time, as can be seen from FIG. 3, the electron beam spot is rotated clockwise by the aberration aberration. If you set the horizontal, (V _"G4) like the tenth help at the time of starting the vertical scanning than (V _'G4) is effective for rotating, the electron beam of the third member (123a) in the counterclockwise direction, the first member ( 121a), the rotation of the electron beam spot due to the deflection aberration in the upper left corner of the screen holder can be corrected.When the electron beam spot has been horizontally scanned to the center of the screen, (V ' _G4 ) and Since V ″ _G4 has substantially the same value, the effects of the first member 121a and the second member 123a cancel each other, and the electron beam spot does not rotate.

Further, when scanned to the upper right nose owner portion, (V ' _G4 ) is larger than (V " _G4 ), and the electron beam spot is rotated clockwise by the effect of the first member 121a, and the deflection aberration is increased. by may cancel the rotation in the counterclockwise direction in the next horizontal during the retrace period, and further the (V _"G4) is set to be higher than (V _'G4), continues to the horizontal scanning period (H), wherein the Similarly, let (V ' _G4 ) gradually become larger than (V " _G4 ). As the electron beam spot is scanned vertically from the top of the screen to the center, the angle of rotation due to deflection becomes smaller (V' _G4 ). _Reduce the difference between and (V " _G4 ). When vertically scanned to the bottom of the screen, as can be seen from FIG. 3, at the left end of the screen, the electron beam spot rotates counterclockwise as opposed to the upper half of the screen, so that the value of (V ' _G4 ) becomes (V _"G4) to be exceeded. If the vertical scanning to screen the lowermost end, so increasing the rotational angle of the electron beam spot caused by the deflection (V _'G4) and (V' _G4) by increasing the difference gradually the correction effect of the Make it strong

The difference between the average value of the values of (V " _G4 ) and (V" _G4 ) and (V _G2 ) is large at the start and end of the horizontal scan (H) and at the start and end of the vertical scan (V). . That is, the potential is set so that the correction effect becomes stronger in the portion where the astigmatism shown in FIG. 3 is large.

As described above, the inclined groove structure formed in the first and third members 121a and 123a of the fourth electrode G4 shown in FIGS. 10A and 10B and the V 'shown in FIG. _By the potential waveforms of _G4 ) and (V " _G4 ), not only the astigmatism of the electron beam spot, but also the rotation of the spot in the nose holder portion can be similarly corrected, so that a circular spot can be obtained generally in the entire screen area.

12 illustrates grooves 101b and 103b that are inclined with respect to the horizontal plane in addition to the fourth electrode G4 and the second member 122a to correct the electron beam rotation more effectively. The direction of inclination needs to be reverse to the direction of the groove portion of the opposing first member 121a and the third member 123a. Therefore, the inclination directions of the grooves on both the front surface and the rear surface of the second member 122a must be opposite to each other.

In FIG. 13, the first, third members 121b and 123b of the fourth electrode G4 face the third electrode G3 and the fifth electrode G5, respectively, to correct the rotation outside the electron beam spot. The groove 13 inclined with respect to the horizontal plane is shown in FIG. 14 and the third, fifth electrodes G3 'and G5' are opposite to the fourth electrode G4 in the horizontal direction. In this embodiment, the inclined groove portion 14 is formed to incline the electron lenses formed between the third and fourth electrodes and between the fourth and fifth polar electrodes.

In any of these embodiments, the respective electronic lenses are inclined in opposite directions by being opposite to each other in the inclined direction of the groove portions formed in the two electrodes. By applying a potential that changes in synchronization with independent deflection currents to the first member 121b and the third member 123b, the rotation of the electron beam spot can be corrected as in the embodiment of FIG.

According to the present invention, by using a single dynamic potential generating circuit, it is possible to correct the astigmatism caused by the electron beam deflection other than the peripheral portion of the color receiver tube at the same time, and also to effectively correct the image curvature. Therefore, the electron beam spot diameter of the periphery of the screen can be reduced, and the uniformity beyond the resolution can be reduced without providing a separate dynamic potential generating circuit for astigmatism correction and top curvature correction.

Another example of the present invention will be described with reference to FIGS. 15A and 15B. A high potential Eb of 20 to 30 KV is applied to the G6 electrode 14 through the shielding cup 15. A medium potential (connection voltage ... V _f ) of 5 to 10 KV is applied to the G3 electrode 11 and the G5 electrode 13. Low potentials of 100 and 1500 V are applied to the G4 electrode 12 divided into three members 121, 122 ′, and 123. UPF lenses are formed by the G3, G4 and G5 electrodes, and BPF lenses are formed by the G5 and G6 electrodes, and the electron beam is focused by the main lens formed by the combination of these two electron lenses.

Long slits in the vertical direction are formed in the openings of the second member 122 arranged in the center of the three members, and the first dynamic potential V ' _G4 that changes in synchronization with the deflection current is applied. The same potential V _G4 is applied to the first and third members 121 and 123 disposed on both sides of the member 122 ′. (V _G4 ) is the dynamic potential that changes in synchronization with the deflection current. When the deflection current is large and the electron beam deflection amount is large (V _G4 ), the value is lowered, the axis-symmetric lens strength formed by the slit is strengthened, and the astigmatism caused by the electron beam deflection is canceled out.

FIG. 16 shows the results of analyzing the effect of the embodiment of FIG. 15 using a calculator rate.

The specific dimensions of the electron gun main lens are as follows.

G3 electrode aperture diameter (G2 electrode side) ø1.5

〃 (G4 electrode side) ø4.0

G3 electrode length 2.7

Opening diameter ø4.0 of the first and third members of the G4 electrode

〃 〃 Electrode length 0.5

Opening diameter of the second member of the G4 electrode (ℓ ₁ ) ø4.0

〃 〃 Slit opening diameter (ℓ ₂ ) ø6.0

Slit width W of the second member of the G4 electrode 3.0

〃 electrode length 0.7

Opening diameter of G5 electrode (G4 electrode side) ø4.0

〃 (G6 electrode side) ø8.0

G5 electrode length 24.3

G6 Electrode opening diameter ø8.0

(Unit: mm)

Further, the voltage applied to the G6 electrode 14 is 25KV, the distance between the shadow mask 4 and the G4 electrode side end of the G3 electrode 13 is 340 mm, and the electron beam is focused on the shadow mask. Let's do it.

)의 값은 저하된다. 이것은 주렌즈 강도가 약하게 되어 있는 것을 나타낸다.The first dynamic voltage V ' _G4 applied to the second member 122' of the G4 electrode and the second dynamic potential V _G4 applied to the first and third members 121 and 123 are applied. is changed, each (V _G4), G3, G5 potential of (V _'G4) an electron beam horizontally halo reversed I eases the spot on the screen central part with respect to the value of (V _f) the value (V _fh), a vertical halo When the rain disappears, the values of the values of the G3 and G5 potentials (V _f ) (V _fv ) become the same, so that astigmatism does not occur in the electron beam. If raising the value of (V _G4) and, lowering the value of (V _'G4) whereas the increase in astigmatism is becomes stronger astigmatism voltage (ΔV _f), i.e., the voltage obtained by subtracting the (V _fh) difference, (V _fh ) And (V _fv ) mean value, that is, average value of focusing voltage (

) Decreases. This indicates that the main lens intensity is weak.

Therefore, if (V _f ) is set to a constant value when (V _G4 ) is raised and (V ' _G ) is decreased, the distance between the position where the electron beam is focused and the main lens is extended to realize dynamic focus. .

In order to correct astigmatism due to deflection, the value of (V _G4 ) is increased when the electron beam is deflected to the periphery of the screen, the value of (V ′ _G4 ) is decreased, and the astigmatism by the main lens is increased. The astigmatism caused by the main lens has an effect of expanding the halo in the horizontal direction and suppressing the halo in the vertical direction. On the other hand, astigmatism due to deflection has a function of strengthening the halo in the vertical direction, so that these astigmatisms can be canceled from each other. When in accordance with the deflection amount of the value of (V _G4) larger, and smaller the value of (V _'G4) can correct the astigmatism caused by the deflection in the parts of the screen.

In this way, the value of (V _G4 ) increases as the amount of deflection increases, and the value of (V ' _G4 ) decreases, thereby correcting astigmatism caused by electron beam deflection and simultaneously achieving dynamic focus.

Astigmatism correction and dynamic focus can be realized simultaneously by fixing the value of (V ' _G4 ) and dynamically changing only (V _G4 ). However, if the value of (V ' _G4 ) is fixed at about 600 to 700 V, the ability of astigmatism correction decreases, causing a problem that the maximum value of (ΔV _f ) decreases to 600 to 750 V. Increasing (V ' _G4 ) further decreases the ability of astigmatism, and conversely, decreasing (V' _G4 ) decreases the capacity of the UPF lens formed of the G3 electrode 11, the G4 electrode 12, and the G5 electrode 13. As the intensity increases and the electron beam is concentrated strongly in the main lens, the beam spot diameter on the screen increases due to the space charge effect, and in particular, the resolution of the center portion of the screen becomes remarkable.

FIG. 17 is an example in which long slits are formed in the horizontal direction on the surface of the first and third members facing the second member in order to strengthen the astigmatism correction effect.

According to the present invention, the same dynamic voltage generation circuit can correct the astigmatism caused by the electron beam deflection to the periphery of the color receiver tube, and also realize the dynamic focus.

According to the present invention, since the slits for the three electron beams are formed in the longitudinal direction, they have little interference with each other and no adverse effect on the convergence characteristic or the like occurs.

In addition, since the first dynamic voltage is applied to the first members 121 and 123 of the G4 electrode and the second dynamic voltage is also applied to the second member 122 ', the second member 122 is applied. The ability of correction of deflection aberration is improved than when the voltage is fixed.

Claims (14)

In the water tube for electron gun having a first electrode group for generating an electron beam to direct the fluorescent surface along the initial passage, and a second electrode group constituting a main lens for focusing each of the electron beam on the fluorescent surface, The second electrode group is composed of third, fourth, fifth and sixth electrodes sequentially arranged from the first electrode group toward the fluorescent surface, and the fourth electrode is directed from the first electrode group toward the fluorescent surface. Consists of sequentially arranged first, second and third members, the second member has a non-circular opening for passing the electron beam, a constant potential is applied, the first and third The member has an opening for passing the electron beam, and a deflection yoke for scanning the electron beam at high speed in the horizontal direction and scanning at a relatively low speed in the vertical direction. A water tube electron gun, characterized in that a potential that changes according to the supplied deflection current is applied. 2. The waterborne electron gun according to claim 1, wherein the non-circular opening has an opening dimension perpendicular to the horizontal direction than an opening dimension in the horizontal direction. 3. The waterborne electron gun as set forth in claim 2, wherein the electric potential applied to said first and third members is increased in accordance with an increase in said electron beam deflection current. 2. The waterborne electron gun according to claim 1, wherein the potentials applied to the first and third members are a common potential with each other. The water gun electron gun according to claim 1, wherein the first and third members each have an elongated groove portion parallel to the horizontal direction around an opening of at least one side of a surface facing the second member. 2. The waterborne electron gun according to claim 1, wherein the opening dimension in at least one of the first and third members is smaller than the opening dimension in the horizontal direction in the vertical direction with respect to the horizontal direction. 3. The first and third members of claim 2, wherein the first and third members each have an elongated horn inclined with respect to the horizontal direction around the opening of the surface facing the second member. Inclined in opposite directions from each other, wherein the first and third members are applied with different potentials varying according to the deflection current. 8. The waterborne electron gun according to claim 7, wherein the second member has an elongated groove portion inclined in a direction opposite to the groove portion of the opposing member on a surface facing the first and third members. The semiconductor device according to claim 1, wherein at least one opposing surface of the opposing surface of the third electrode and the first member and of the opposing surface of the fifth electrode and the third member is parallel to the horizontal direction. A waterborne electron gun characterized by having a long groove. 8. The method of claim 7, wherein the potential that changes in synchronization with the deflection current is separately applied to the first and third members, and a first electron lens is provided in the electron beam path between the first and second members. And a second electron lens is formed in the electron beam path between the second and third members, respectively, and when the electron beams are deflected in a direction perpendicular to the horizontal direction, the first and second electron lenses. When the electron beams are deflected in a direction parallel to the horizontal direction by making the intensity substantially matched, it is preferable to make one of the first and second electron lenses stronger than one of the other electron lenses. A water-borne gun. In a water tube electron gun having a first electrode means for generating an electron beam to direct the fluorescent surface along the initial passage and a second electrode means constituting a main lens for focusing the electron beam on the fluorescent surface, The lens is composed of G3 electrodes, G4 electrodes, G5 electrodes, and G6 electrodes sequentially arranged from the first electrode means toward the fluorescent surface, and a high potential is applied to the G6 electrodes, and a medium potential is applied to the G3 and G5 electrodes. And dividing the G4 electrode into the first member, the second member, and the third member from the first electrode means toward the fluorescent surface, and the electron beam through hole formed in the second member is non-circular. A potential that changes in synchronization with the deflection current is applied to the first, second, and third members, and the potential applied to the first and third members is different from the potential applied to the second member. It is characterized by Tolerance Award gun that. 12. The diameter in the horizontal direction of the electron beam through hole formed in the second member is compared with a diameter in a plane perpendicular to the horizontal direction and including one of the initial passages corresponding to each opening hole. And the potential applied to the first and third members increases with increasing electron beam deflection, and the potential applied to the second member decreases. 12. The waterborne electron gun according to claim 11, wherein the potential applied to said first member and said third member is common. 12. The water phase as claimed in claim 11, wherein a groove is formed in the periphery of the electron beam through hole on both or one surface of the first member and the third member, and each groove portion has a symmetrical plane coinciding with the horizontal direction. Tolerance gun.

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