JP2827306B2 - Image display device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat display device in a video device.

2. Description of the Related Art Conventionally, a cathode ray tube is mainly used as a display device for displaying color television images, but a conventional cathode ray tube has a very long depth compared to a screen, and a thin television receiver is manufactured. It was impossible to do. Recently, EL display devices, plasma display devices, liquid crystal display devices, and the like have been developed as flat display devices, but all of them are insufficient in terms of performance such as luminance, contrast, and color reproducibility of color display.

Accordingly, a novel display device has been proposed in Japanese Patent Application No. 62-288762 to achieve a flat display device using an electron beam.

This divides the screen on the screen into a plurality of sections vertically, deflects the electron beam vertically for each section, displays a plurality of lines, and further divides the screen vertically into a plurality of sections. The phosphors of R, G, B, etc. are sequentially emitted for each section, and the irradiation amount of the electron beam to the phosphors of R, G, B, etc. is controlled by a color video signal, as a whole. This is for displaying a television image.

FIG. 3 shows the internal configuration of a conventional image display device. Third
In the figure, 1 is a back electrode, 2a to 2c are line cathodes as an electron beam source, 3 is an electron beam extraction electrode, 4 is a signal electrode, 5 is a focusing electrode, 6 is a horizontal deflection electrode, 7a and 7b are These components are vertical deflection electrodes.
And 9, and the inside of the container was evacuated. The linear cathodes 2a to 2c are stretched in the horizontal direction so as to generate an electron current having a substantially uniform current density distribution in the horizontal direction. In the figure, only three of 2a, 2b, and 2c are shown). These line cathodes are formed, for example, by coating a surface of a tungsten wire with an oxide cathode material.

The back electrode 1 is made of a flat conductive material,
It is provided in parallel to 2 c.

The extraction electrode 3 is opposed to the back electrode 1 via the linear cathodes 2a to 2c and has through holes 10 provided at appropriate intervals in the horizontal direction.
Of the conductive plate 11 on a horizontal line facing each line cathode.
Consists of

The signal electrode 4 comprises a row of a plurality of vertically elongated conductive plates 12 arranged at predetermined positions at positions horizontally opposed to each of the through holes 10 in the extraction electrode 3,
Each conductive plate has a similar through-hole 13 at a position facing the through-hole 10 of the extraction electrode 3.

The focusing electrode 5 includes a conductive plate 15 having a through hole 13 at a position facing the through hole 13 of the signal electrode 4.

The horizontal deflection electrode 6 is a vertically elongated conductive plate on the same plane facing the middle of the row of the through-holes 14 of the focusing electrode 5.
16a and 16b are arranged so as to form a pair of horizontal deflection electrodes, and have a fence shape as a whole.

The vertical deflection electrodes 7a and 7b have a structure in which two comb-shaped conductive plates are engaged with each other on the same plane with an appropriate interval therebetween. The plate 18a and the upper conductive plate 18b form a pair of vertical deflection electrodes.

The screen 19 is formed by applying a phosphor 20 that emits light by irradiation with an electron beam to the inner surface of the glass container 8 and adding a metal back layer (not shown) thereon.

In order to obtain a highly uniform image in which the seam of the image small area 21 is not visible, it is necessary to process and position each electrode with high precision when processing and assembling the electrodes. However, each of the electrode groups 3 to 6 and 7a and 7b is a thin conductive plate, and it is necessary to control the processing accuracy down to the micron order by etching the through holes 13, 14 and slits. is there.

In particular, a large number of conductive plates separated like horizontal deflection electrodes 6
In the case of 16a and 16b, at first, an appropriate bar is provided on the 16a and 16b to be processed by etching as a single piece that is partially connected, and it is manufactured through other electrodes and insulating spacers. After laminating and fixing with the bonding glass, unnecessary bars are removed by a method such as a laser beam cutting process, so that the conductive plates 16a and 16b are finally electrically divided.

FIGS. 4A and 4B show the cross-sectional shape of each electrode in the above embodiment.
Shown in In FIG. 4, 1 is a back electrode, 2 is a line cathode, 3
Is an electron beam extraction electrode, 4 is a signal electrode, 5 is a focusing electrode, 6 is a horizontal deflection electrode, and 7 is a vertical deflection electrode. The cross-sectional shapes of the holes and slits of each electrode are arranged in the direction opened to the screen 19.

Problems to be Solved by the Invention However, in such a structure, the dimensional accuracy of the cross sectional shapes of the horizontal deflection electrode 6 and the vertical deflection electrode 7 varies.
There is a concern that the linearity of the spot position of the electron beam on the screen plate is deteriorated.

The present invention has been made in view of the above problems, and provides an image display device that realizes a high-quality image.

Means for Solving the Problems In order to solve the above problems, the present invention provides a rear electrode, a line cathode as an electron beam source, an extraction electrode, a signal electrode, a focusing electrode, and a horizontal / vertical deflection electrode from the back of the screen to the front. And a screen plate are arranged, and in a flat display device in which these are housed inside the vacuum of a flat glass bulb, the cross-sectional shape of the slits of the horizontal deflection electrode and the vertical deflection electrode is closed with respect to the screen plate. It has a structure.

The present invention has a structure in which the horizontal deflection electrode and the vertical deflection electrode have the above-described structure, so that when controlling the spot position of the electron beam on the screen plate, the etching accuracy of the horizontal deflection electrode and the vertical deflection electrode processed by etching is good. By directing the surface in the direction of the large potential gradient, distortion of the equipotential surface between the electrodes is reduced, and a high-quality image can be obtained by controlling the spot position of the electron beam with high precision.

Embodiment Hereinafter, an image display device according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a sectional shape of an electrode for controlling an electron beam of an image display device according to an embodiment of the present invention. In FIG. 1, (A) uses the symbols in FIG.
FIG. 3 is a YZ sectional view, and FIG. 3B is an XZ sectional view. In FIG. 1, 22 is a back electrode, 23 is a linear cathode, 24 is an extraction electrode, 25 is a signal electrode, 26 is a focusing electrode, 27 is a horizontal deflection electrode,
28 is a vertical deflection electrode and 29 is a screen plate. As shown in FIG. 1, the cross sectional shape of the electrode for controlling the electron beam of the horizontal deflection electrode 27 and the vertical deflection electrode 28 is different from that of the screen plate 29.
It has a closed tapered hole shape.

2A and 2B show simple trajectories of the electron beam 30 in this embodiment. As shown in FIG. 2, even if the cross-sectional shape of the horizontal deflection electrode 27 and the vertical deflection electrode 28 is a surface having a large tapered hole and the etching accuracy is deteriorated, the electron beam has a large spot position 31 on the screen plate 29. It can be controlled without affecting.

Effects of the Invention As described above, according to the present invention, since the electrode cross-sectional shapes of the horizontal deflection electrode and the vertical deflection electrode have a closed shape with respect to the screen plate, the electrode cross-sectional shape of the horizontal deflection electrode and the vertical deflection electrode When the closed surface of the cross-sectional shape with good dimensional accuracy is opposed to the screen plate, the surface with high accuracy is directed to the larger potential orientation, and the distortion of the equipotential surface between each electrode is reduced. Since the spot position of the electron beam can be controlled with high precision, a high-quality image can be obtained.

[Brief description of the drawings]

1A and 1B are cross-sectional views showing an electrode cross-sectional shape of an image display device according to an embodiment of the present invention. FIGS. 2A and 2B are cross-sectional views showing electron beam trajectories of the image display device. 4 is an exploded perspective view showing an internal configuration of a conventional image display device, and FIGS. 4A and 4B are cross-sectional views showing electrode cross-sectional shapes of the conventional image display device. 22 ... back electrode, 23 ... wire cathode, 24 ... lead electrode,
25 ... signal electrode, 26 ... focusing electrode, 27 ... horizontal deflection electrode, 28 ... vertical deflection electrode, 29 ... screen plate.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-2-61947 (JP, A) JP-A-55-136443 (JP, A) JP-A-62-244667 (JP, A) JP-A-60-1985 189145 (JP, A) JP-A-59-146143 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01J 31/15, 31/12

Claims (1)

(57) [Claims] A back electrode extending from the back to the front of the screen;
In a flat display device in which a linear cathode, an extraction electrode, a signal electrode, a focusing electrode, a horizontal deflection electrode, a vertical deflection electrode, and a screen plate are arranged as an electron beam source, and these are housed inside a flat glass bulb vacuum, An image display device in which the cross-sectional shapes of the horizontal deflection electrode and the vertical deflection electrode are closed with respect to the screen plate.