JP2804052B2 - Color picture tube equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a color picture tube device, and more particularly, to a method in which three electron beams arranged in-line are used to form a large common electron beam. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color picture tube device having an electron gun which focuses and concentrates a beam by an aperture electron lens.

(Prior Art) Generally, a color picture tube device is configured as shown in FIG. 5, a vacuum envelope 1 includes a face plate 3, a funnel 4 joined to a side wall 3a of the face plate 3, and
And a neck 5 joined to the funnel 4.

A film-like screen 2 made of a phosphor is formed on the inner surface of the face plate 3, and a shadow mask 9 having a large number of apertures 8 is provided at a predetermined interval from the screen 2. An electron gun 6 is mounted in the neck 5.

Further, the inner conductive film 10 is uniformly applied from the inner surface of the funnel 4 to a part of the inner surface of the neck 5,
An external conductive film 11 is uniformly applied on the outer surface of the substrate, and an anode terminal (not shown) is provided on a part of the outer surface of the funnel 4.

A deflection yoke 7 is mounted on the outside from the funnel 4 to the neck 5.

The screen 2 is formed by coating a large number of red, green, and blue light-emitting phosphors in a stripe or dot shape, and the three electron beams emitted from the electron gun 6 during operation.
B _R , B _G and B _B are selected by the shadow mask 9 and bombard the respective phosphors to emit light.

Further, the electron gun 6 the three electron beams B _R parallel in-line array generates a B _G and B _B, and the electron beam forming unit GE for accelerating and controlling, focusing these electron beams, for concentrating Of the main electron lens portion ML. And
Three electron beams B _R, by deflecting and scanning the screen 2 over the entire surface by the deflection yoke 7 B _G and B _B, to form a raster.

By the way, a method of concentrating three electron beams is disclosed in, for example, US Pat. No. 2,957,106,
There is a technique in which an electron beam emitted from a cathode is inclined and concentrated from the beginning, and US Pat. No. 3,772,55
As shown in the specification of JP-A No. 4, by eccentrically opening the openings on both sides of some of the three electron beam passage openings provided in the electron gun electrode slightly outward from the center axis of the electron gun. There is a technology for concentrating an electron beam, all of which are widely adopted.

The deflection yoke 7 basically includes a horizontal deflection coil for generating a horizontal deflection magnetic field for deflecting the electron beam in the horizontal direction, and a vertical deflection coil for generating a vertical deflection magnetic field for deflecting the electron beam in the vertical direction. have. In an actual color picture tube device, when the electron beam is deflected, the concentration of the three electron beam spots on the screen 2 is destroyed. Therefore, a device is devised to prevent the collapse of the concentration.

This is called a convergence-free system, in which the horizontal deflection magnetic field is of a pincushion type and the vertical deflection magnetic field is of a barrel type, so that three electron beams are concentrated in the entire area of the screen 2.

As described above, the quality of the color picture tube device has been improved by adopting many development techniques, but as the size and quality of the tube have become widespread, new problems have been highlighted.

That is, there are a problem of a beam spot diameter of the electron beam on the screen 2, a problem of a distortion of the electron beam spot at a peripheral portion of the screen 2 when deflected, and a problem of convergence on the entire surface of the screen 2.

When the tube becomes large, the distance from the electron gun 6 to the screen 2 increases, the electron optical magnification of the electron lens increases, the beam spot diameter on the screen 2 increases, and the resolution deteriorates. Would. To reduce the beam spot diameter, the performance of the electron lens of the electron gun 6 must be improved.

Generally, the main electron lens portion is formed by arranging a plurality of electrodes having openings on the same axis and applying a predetermined potential to each of the electrodes. There are several types of such electrostatic lenses depending on the difference in the electrode configuration, but basically, a large aperture lens with a large electrode aperture diameter is formed, or the distance between the electrodes is increased to provide a gentler lens. By forming a long focal length lens by changing the potential, the lens performance can be improved.

However, since the electron gun 6 of the color picture tube is enclosed in the neck 5 which is generally a thin glass cylinder, the aperture of the electrode, that is, the lens aperture is first physically restricted. Also, the distance between the electrodes is limited so that the focused electric field formed between the electrodes is not affected by other unwanted electric fields in the neck 5.

In particular, when three electron guns are integrated in a delta arrangement or an inline arrangement as in a shadow mask type color picture tube, as described above, the smaller the electron gun interval Sg, the more the three beams are projected onto the screen 2. It is easy to concentrate on one point near the entire surface. Further, since there is an advantage that the deflection power is small, the opening of the electrode must be further reduced in order to reduce the electron gun interval Sg.

Therefore, a method is considered in which three electron lenses arranged on the same plane are completely overlapped to form a large electron lens, and the large-diameter electron lens is used to maximize the performance of the electronic lens.

FIG. 6 illustrates this optically. As shown in the figure, the core of the projected electron beam is small, but the result is still insufficient when viewed as a whole. That is, the electron gun distance clogging parallel electron beam of the three beams interval is Sg B _R, when B _G and B _B passes through one common large-aperture electron lens LEL, the central electron beam as in the Figure 6 When _BG is properly focused, the electron beams B _{R on} both sides,
B _B is not accompanied large coma with over-focusing state, and the over-concentrated state, on the screen 101, three beam spots SP _R, SP _G, and SP _B are far apart, either side of the beam distorted.

In order to reduce the coma aberration by adjusting the concentration of these three electron beams, if the distance Sg between the three beams with respect to the lens diameter D of the electron lens LEL is reduced to some extent, there is a practical problem. However, regarding the concentrated state of the three beams on the screen 101, the beam interval Sg must be extremely small, and there is a limit in terms of mechanical arrangement of the electron beam generator.

Therefore, Japanese Patent Publication No. Sho 49-5951 (U.S. Pat.
No. 6,528,476 and U.S. Pat. No. 4,528,476, as shown in FIG. 7, three electron beams incident on the electron lens LEL are previously inclined so that the three electron beams are simultaneously emitted. The three electron beams are focused so as to pass through the center of the electron lens LEL, and then the divergent electron beams on both sides are strongly deflected in the opposite direction by the second electron lens LEL2. , Three beams are concentrated on the screen 101.

As a result, the focusing and focusing of the three electron beams is improved. However, the electron beams on both sides have a problem that large deflection aberration or coma aberration occurs.

For this reason, as shown in FIG. 8 (a), in order to correct over-concentration of the electron beam, a plate-like body having a non-circular aperture 12 common to the three electron beams shown in FIG. 8 (b) 13 is arranged near the large-diameter electron lens and on the electron beam generating side,
A method has been proposed in which three electron beams pass through a large-diameter electron lens without crossing each other.

However, in such a method, since the plate 13 has a common aperture for the three electron beams, it is necessary to correct the convergence characteristics of the large-diameter electron lens and to completely correct the focusing state of the three electron beams. Is difficult to achieve, and a large coma aberration remains in the focused beam spot, which is not practical.

As described above, it is difficult to use a large-diameter electron lens that works commonly for three electron beams, and it is not possible to maximize the performance of the large-diameter electron lens.

(Problems to be Solved by the Invention) As described above, in order to further improve the image performance of the color picture tube device, by using a large-diameter electron lens common to three electron beams, the electron gun 6 Although it is effective to improve the performance and reduce the beam spot diameter on the screen 2, the performance of the large-diameter electron lens cannot be sufficiently exhibited by the conventional technique, and the image performance of the color picture tube apparatus is further increased. There is a problem that it is difficult to improve.

SUMMARY OF THE INVENTION An object of the present invention is to provide a color picture tube device in which the performance of a large-diameter electron lens is sufficiently exhibited and image performance is remarkably improved.

[Constitution of the Invention] (Means for Solving the Problems) The present invention includes an in-line type electron gun, a deflection yoke, and a screen, and emits an electron beam emitted from the electron gun section on the screen by the deflection yoke. In a color picture tube apparatus that performs deflection scanning in the vertical and horizontal directions, the electron gun generates, accelerates, and controls three electron beams, an electron beam forming unit including a cathode, and a main electron that focuses and concentrates the electron beams. A lens portion, and the main electron lens portion has a common electron lens for three electron beams composed of overlapping cylindrical electrodes, and only in the lens region on the cathode side of the common electron lens, It has an electrode with three beam passage holes, the three beam passage holes are the same size on both sides, the central beam passage hole is smaller, and Child beam is a color picture tube apparatus comprising configured to enter the central beam toward the corresponding beam passage holes.

(Operation) According to the present invention, the first electron lens commonly acting on the three electron beams incident parallel to the main electron lens portion, and the three electron beams in the lens region of the first electron lens are provided. The electrode having the beam passage hole is composed of a compound electron lens having three individual second electron lenses, and the three individual second electron lenses have a central electron lens that has a more focusing action than the electron lenses on both sides. Is set to be strong, and each electron beam on both sides is set to be incident near the center beam of the corresponding second electron lens.

As a result, each electron beam on both sides is subjected to coma aberration by the second electron lens, however, the first electron lens is then subjected to coma aberration in the opposite direction, so that the coma aberration is canceled out and is well focused on the screen. I do.

Further, since the lens intensity can be set so as not to cause overconcentration by the first electron lens, the three electron beams can be satisfactorily concentrated near the screen.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

The present invention is an improvement of the electron gun in order to solve the above-mentioned problem, and will mainly describe the electron gun.

The electron gun of the color picture tube device according to the present invention is configured as shown in FIG. 1, which shows the vicinity of the neck and the vicinity of the screen.

That is, if the same parts as those in the conventional example (FIG. 5) are denoted by the same reference numerals, the electron gun 100 mounted in the neck 5
Are the cathode (cathode) K, the first grid G1, the second grid G2, the third grid G3, the fourth grid G4, and the fifth grid
G5 and a sixth grid G6 are arranged at predetermined intervals, and these are supported by an insulating support (not shown). A valve spacer 112 is fixed to the sixth grid G6, and the valve spacer 112 is in contact with the inner conductive film 10 uniformly applied from the inner surface of the funnel 4 to a part of the inner surface of the neck 5. Note that such an electron gun 100 is fixed to a stem pin 113 below the neck 5.

The cathode K of the above, has a respective internal heater, generates three electron beams B _R, B _G and B _B.

Each of the first grid G1 and the second grid G2 has three relatively small beam passage holes corresponding to the three cathodes K, and controls and accelerates an electron beam from the cathode K in this portion. The beam forming unit GE is configured.

Next, the third grid G3, the fourth grid G4, and the fifth grid G5 (the fourth grid G4 side) also have three relatively large beam passage holes corresponding to the three cathodes K.

In a portion of the fifth grid G5 close to the sixth grid G6 side, three beam passage holes 14, 15, as shown in FIG.
An electrode G5D having 16 is provided. As can be seen from FIG. 2, of the three beam passage holes 14, 15, 16 the beam passage holes 14, 16 on both sides are the same size, but the beam passage hole 15 in the center is smaller than both sides. ing.

Also, the sixth grid G6 partially overlaps the fifth grid G5,
A substantially cylindrical electrode including a fifth grid G5 which is a cylindrical electrode, and a substantially large-diameter cylindrical lens is formed between the fifth grid G5 and the large circular beam passage hole G5T. .

Further, as described above, a valve spacer 112 is attached to the outer periphery of the tip of the sixth grid G6, and the inner conductive film 10 is uniformly applied from the inner surface of the funnel 4 to a part of the inner surface of the neck 5. The anode terminals are in contact with each other, and an anode terminal provided on the funnel 4 supplies an anode high voltage. A deflection yoke 7 is provided at the tip of the sixth grid G6.
And a magnetic field correction element for the magnetic field caused by the magnetic field.

Above, the cathode K, the first grid G1 to the sixth grid
G6 is fixedly supported by the insulating support.

Further, as described above, on the outside of the neck 5 toward the funnel 4 and the deflection yoke 7 is mounted, three electron beams B _R from the deflection yoke 7 is an electron gun, B _G, and
BB consists of a horizontal deflection coil and a vertical deflection coil for deflecting _B horizontally and vertically. Further, a multipole magnet 51 is provided for adjusting the trajectory of the electron beam.

Except for the sixth grid G6, a predetermined voltage is externally applied to all the electrodes through the stem pins 113.

In the above electrode configuration, the voltage applied to each electrode will be described. For example, the cathode K has a cutoff voltage of about 150 V, a video signal is applied thereto, and the first grid G1
Is the ground potential, the second grid G2 is 500V to 1KV, the third grid G3 is 5 to 10KV, the fourth grid G4 is 500V to 3KV, the fifth grid G5 is 5 to 10KV, and the sixth grid G6 is the anode high voltage. Apply 25-35KV.

With such a potential configuration, the electron beam generated from each cathode K in accordance with the modulation signal is transmitted by the cathode K, the first grid G1, and the second grid G2.
A crossover CO is formed as shown in FIGS. 3 and 4, and is slightly focused by the pre-focus lens PL formed by the second grid G2 and the third grid G3 to form a virtual crossover VCO. Then, each electron beam B _R has entered into the third grid G3, the B _G and B _B are the main electron lens unit ML1 according to the sixth grid G6 of the third grid G3, the electron beam focusing action and both sides concentrated Focused and concentrated on the screen 2 under the action. FIGS. 3 and 4 are optical models of the YZ section and the XZ section of FIG. 1, respectively.

Next, the lens operation of the main electron lens portion ML1 from the third grid G3 to the sixth grid G6 will be described in more detail with reference to FIGS.

Individual electron beam that has entered to form a virtual crossover VCO to the third grid G3, the third grid G3, fourth grid G4, respectively individual, by a weak unipotential lens EL ₂ formed by the fifth grid G5 Focused a little.

The large-diameter electron lens LEL is formed by the fifth grid G5 and the sixth grid G6, and is provided by an electrode G5D having three beam passage holes provided near the sixth grid G6 in the middle of the fifth grid G5. Since the penetration of the high voltage from the sixth grid G6 side is controlled, the tip G5T of the fifth grid G5 (a large opening common to the three electron beams) and the cylinder of the sixth grid G6 (the three electron beams One large first electron lens LL is formed by a large aperture common to the first and second lenses. At the same time, in this lens region, three individual second electronic lenses SL (SL ₁ , SL ₂ , SL ₃ ) are formed on the low voltage side.

Accordingly, first, the strength of the electron lens LL is determined so that the three electron beams are concentrated in the vicinity of the screen 2, and the deficiency relating to the focusing is compensated for by the three individual second electron lenses SL. ing.

At this time, the lenses SL ₁ and SL ₃ on both sides are weaker than the center lens SL ₂ so that the beam passage holes 14, 15, 16 of the electrode G5D are formed.
As shown in FIG. 2, the beam passage holes 14 and 16 on both sides are larger than the beam passage hole 15 in the center. This cancels out the difference between the focusing power for the electron beams on both sides by the electron lens LL and the focusing power for the central electron beam.

Also, the center of the beam passing holes 14, 16 on both sides of the electrode G5D is
Unlike the electron beam incident position, that is, the center axis of the beam passage hole on both sides of the first to fourth grids G1 to G4, the electron beam is shifted away from the center. For this reason, the horizontal direction (X-Z
With respect to the surface, the electron beams on both sides of the electron lenses SL ₁ and SL ₃ pass nearer to the central axis (Z axis), respectively, and generate coma aberration. Since the directions are opposite to each other, the coma aberration is negligible for the electron beams on both sides that are canceled and converged on the screen 2, and the electron beams on both sides also form good spots.

The specific dimensions of the above embodiment are as follows, for example.

 Cathode K spacing Sg ≒ 4.92mm, opening (beam passage hole) diameter of each electrode First grid G1 ≒ 0.62mm, Second grid G2 ≒ 0.62mm, Third grid G3 ≒ 4.52mm, Fourth grid G4 ≒ 4.52mm , Electrode G5D ≒ 4.52 mm, electrode G5T ≒ 25.0 mm, electrode D5 ≒ 25.0 mm, sixth grid G6 ≒ 28.0 mm, electrode D6 ≒ 28.0 mm, center opening of electrode G5D ≒ 4.52 mm, both sides opening ≒ 10.0 mm, each Electrode length 3rd grid G3 ≒ 6.2mm, 4th grid G4 ≒ 2.0mm, 5th grid G5 ≒ 55.0mm, 6th grid G6 ≒ 40.0mm, (Length from electrode G5T) Distance between electrodes 1st The distance between the grid G1 and the second grid G2 is about 0.35 mm, the distance between the second grid G2 and the third grid G3 is about 1.2 mm, the distance between the third grid G3 and the fourth grid G4 is about 0.6 mm, and a is about 14 mm.

[Effects of the Invention] As described above, according to the present invention, the performance of the common large-diameter electron lens is sufficiently exhibited, and three parallel electron beams generated from the cathode by the common large-diameter electron lens are produced. Focusing can be performed on the screen in an optimum focusing state and an optimum focusing state, respectively.

Therefore, a very small beam spot can be realized on the screen, and a color picture tube device with significantly improved image performance can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of a color picture tube device according to one embodiment of the present invention, FIG. 2 is a plan view showing electrodes forming a main electron lens in the color picture tube device of the present invention,
3 and 4 are optically equivalent views of the electron gun in the color picture tube device of the present invention, FIG. 5 is a schematic sectional view showing the whole of a general color picture tube device, and FIGS. 6 and 7. FIG. 8A is a configuration diagram optically showing a conventional electron gun (two examples), FIG. 8A is a cross-sectional view showing another conventional electron gun, and FIG. 8B is an electron gun shown in FIG. FIG. 4 is a plan view showing an electrode (plate-like body) forming a main electron lens in FIG. 2 ... Screen, 100 ... Electron gun, GE ... Electron beam forming unit, ML1 ... Main electron lens unit, LEL ... Common large-diameter electron lens, LL ... First electron lens (common), SL ... ... Second electronic lens (individual).

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Jiro Shimokawabe 1-9-2 Hara-cho, Fukaya-shi, Saitama Prefecture Inside the Toshiba Fukaya CRT factory (56) References JP-A-60-54143 (JP, A) JP-A-61-2240 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01J 29/48-29/51

Claims (1)

(57) [Claims] 1. A color picture tube apparatus comprising an in-line type electron gun, a deflection yoke, and a screen, and deflects and scans an electron beam emitted from the electron gun section in the vertical and horizontal directions on the screen by the deflection yoke. In the above, the electron gun includes an electron beam forming unit including a cathode for generating, accelerating, and controlling three electron beams, and a main electron lens unit for focusing and concentrating the electron beam, and the main electron lens unit includes: It has a common electron lens for three electron beams composed of overlapping cylindrical electrodes, and has an electrode with three beam passage holes only in the area of the cathode side lens of this common electron lens. The three beam passage holes have the same size on both sides of the beam passage hole, the central beam passage hole is smaller than that, and each electron beam on both sides has the central beam passage hole of the corresponding beam passage hole. A color picture tube device characterized in that it is configured to be incident closer to the camera.