JPH0346738A - Flat board type image display unit and operating method thereof - Google Patents

Abstract

PURPOSE:To make the deflection angle of each of electron beams constant so as to improve linearity in vertical scanning by varying the divided pitch of a vertical scanning deflecting electrode assembly, the width thereof or a space between the deflecting electrode assembly and a shielding electrode assembly, or varying the level of each of deflecting voltages impressed upon the deflecting electrode assembly to every horizontal scanning cycle. CONSTITUTION:Each of electron beams 21 is sequentially deflected to the side of a shielding electrode assembly 13 by means of a vertical scanning deflecting electrode assembly 11 according to each of impressed voltages. The pitch lB of the electrode assembly 11 and the width WB thereof are both formed by varying both sequentially from the side of a focusing electrode 20 in a ratio determined on a space between the electrode assemblies 11, 13 and on a voltage impressed upon each of the electrode assemblies 11, 13. Or each corresponding voltage is impressed upon each of electrodes, 11a to 11n, all constructing the deflecting electrode assembly, while verying the level of each of impression voltages sequentially by a constant voltage to every horizontal scanning cycle in such a manner that about the same voltage as the electrode assembly 13 is impressed upon the electrode 11n closest to the electrode 20 and the maximum-value voltage on the other hand is impressed upon the top-portion electrode 11a. The deflection angle of each of the electron beams 21 can thus be made constant to improve linearity in the vertical scanning of the beams 21 on the electrode assembly 13.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a flat image display device used in color television receivers and computer terminal displays.

2. Description of the Related Art Flat plate image display devices have been widely used for displays. As this flat panel type image display device, for example, the configuration described in Japanese Patent Application No. 1983-27099 filed by the present applicant is known.

Hereinafter, a conventional flat panel image display device will be explained with reference to FIG.

In FIG. 3, a light emitting section 10 made of a fluorescent material is provided on the inner surface of the vacuum envelope 9. A horizontally long vertical scanning deflection electrode 11 divided in correspondence with the horizontal scanning line is provided on the inner surface of the vacuum envelope 12 at a distance from and substantially parallel to the light emitting unit 10. Vertical scanning deflection electrode 11 and light emitting section 1
In the space between 0 and 0, there is a planar shield electrode 13 having an electron beam passing hole formed therein at a predetermined distance from the vertical scanning deflection electrode 11 side, and a planar shield electrode 13 which is divided horizontally by a predetermined pinch. A modulation electrode 14 having an electron beam passage hole formed in the electrode, and a horizontal deflection electrode 15 vertically divided into two in a comb-like shape are arranged. Although not shown between each electrode, insulating spacers or the like are inserted and integrated in order to maintain a predetermined constant interval and to fix each electrode.

Furthermore, a thin wire-shaped electron beam generation source is disposed in an extension along the surface direction of the light emitting section 10, and its configuration includes a focusing electrode 20 for focusing and positioning the electron beam from the light emitting section side, and an electron beam generating source. 62 electrodes 19 for extracting the beam
, a 61-electrode 18 for controlling the amount of electron beam, a linear cathode 17 for generating electrons, and a back electrode 16.

Next, the operation of the flat panel image display device shown in FIG. 3 will be explained using FIGS. 4 to 6.

In FIG. 4, electrons generated by heating the linear cathode 17 are drawn out to the focusing electrode side by a predetermined potential applied to the back electrode 16, the G1 electrode 18, and the G2 electrode 19, and are drawn out by the focusing electrode 20. The electron beam is focused, and then the electron beam 21 travels through a space where the vertical scanning deflection electrode 11 and the shield electrode 13 face each other. here,
As shown in FIG. 6, the vertical scanning deflection electrode 11a has a potential (E, .
) is always applied to the vertical scanning deflection electrode 11b from the start of one field (IV) period to one horizontal scanning period (IH
), the voltage applied to the shield electrode 13 and a pulse of approximately concave voltage (E, , ) are applied to the vertical scanning deflection electrode 11.
A pulse voltage that becomes longer for each horizontal scanning period is applied to C for a 2H period, a 3H period to the vertical scanning deflection electrode lid, and so on, and a voltage of the EBP value is constantly applied to the vertical scanning deflection electrode 11n. put. As a result of the above, vertical scanning deflection electrode 1
The electron beam 21 that has traveled straight between 1 and the shield electrode 13
21a, 21b, and 21C can perform a vertical scanning operation by sequentially changing the vertical position on the light emitting section 10. Next, as shown in FIG.
1 is deflected toward the shield electrode 13 side, and the shield electrode 1
The electron beam 21 incident on the electron beam 21 passes through the shield electrode 13 in which electron beam passing holes are provided at a predetermined pitch in the horizontal direction, and thereby becomes an electron beam divided into equal pinches in the horizontal direction. Next, each of the horizontally divided electron beams 21 is modulated by the modulation electrode 14. The modulated electron beams are deflected simultaneously in the horizontal direction by a shield electrode 13 and a horizontal deflection electrode 15 having a passage hole corresponding to the electron beam passage hole of the modulation electrode 14, and are deflected from the phosphor. The light emitting unit 10 is made to emit light to display characters, images, etc. In order to display a color image, a light emitting section 10 is formed by repeating vertically long striped color phosphors of red (R), green (G), and blue (B) sequentially in the horizontal direction, and each electron beam is R, G in synchronization with the horizontal scanning position.

A B color signal is applied to the modulation electrode 14.

Problems to be Solved by the Invention However, in the above configuration, the electric field near the focusing electrode 20 between the vertical scanning deflection electrode 11 and the shield electrode 13 is
There was a problem in that the linearity of vertical scanning in the vicinity was disrupted due to the influence of the electrostatic lens that is formed between the electron beams and the electron beam focusing point. In addition, in order to obtain a uniform electron beam spot over the entire display screen, when a correction voltage is applied to the focusing electrode 20 in synchronization with vertical scanning, the speed of the electron beam incident on the vertical scanning deflection area also changes. There was a problem in that the linearity of scanning was disrupted.

The present invention aims to improve the linearity of vertical scanning in view of the occurrence of distortion in displayed images due to the nonlinearity of vertical scanning as described above.

Means for Solving the Problems In order to achieve the above object, the technical solutions of the present invention firstly change the pitch and width of the vertical scanning deflection electrodes near the focusing electrodes. The second method is to change the deflection voltage (E Bo) applied to the vertical scanning deflection electrode in synchronization with vertical scanning.

First, when the pitch and width of the vertical scanning deflection electrodes are equal, the nonlinearity of the vertical scanning caused by the difference in the angle at which the electron beam is deflected depending on the position in the vertical scanning deflection space can be corrected by the vertical scanning deflection. This can be improved by changing the pitch and width of the electrodes. Second, by changing the voltage applied to the vertical scanning deflection electrode, the electron beam is deflected at a constant angle, thereby improving the linearity of vertical scanning.

EXAMPLE Hereinafter, a first example of the present invention will be described with reference to FIG. FIG. 1 is a vertical sectional view of the conventional flat panel image display device shown in FIG. 3, with parts from the modulation electrode 14 to the vacuum envelope 9 omitted. In FIG. 1, from the back electrode 16 to the focusing electrode 20 is an electron gun that generates an elongated electron beam in the horizontal direction of the screen, including the back electrode 16, the linear cathode 17, and the G1 electrode 18.
, G gold electrode 19, and a focusing electrode 20, 11
A vertical scanning deflection electrode is used to sequentially deflect the electron beam generated from the electron gun toward the light emitting section, and is divided into a plurality of electrodes in the vertical direction of the screen. 13 is a shield electrode provided opposite to the vertical scanning deflection electrode 11.

The operation of the above configuration will be explained. First, the electron beam 21 generated from the electron gun section consisting of the back electrode 16 and the focusing electrode 20 travels in the vertical direction between the vertical scanning deflection electrode 11 and the shield electrode 13 and is applied to each of the vertical scanning deflection electrodes 11. The applied voltage causes the beam to be sequentially deflected toward the shield electrode. Here, the vertical scanning deflection electrode 11
The pitch AB and the width Wa are changed at a predetermined ratio from the focusing electrode 20 side, and the ratio is determined by the distance between the vertical scanning deflection electrode 11 and the shield electrode 13, the voltage applied to those electrodes, and the focusing electrode 20. It is determined by the voltage applied to the electrode 20, etc. This embodiment shows a case where a voltage higher than the voltage EBP applied to the shield electrode 13 is applied to the focusing electrode 20, and due to the influence of the focusing electrode 20, the focusing electrode 20
Since the electric field in the nearby vertical scanning deflection region is stronger than in other regions, the electron beam 21 is
The sensitivity to deflect to the side becomes lower. For this reason, the focusing electrode 20
By increasing the pitch and width of the vertical scanning deflection electrodes 11 on the side, the electron beam 21 incident on the shield electrode 13 can be
The position interval (tv) for each horizontal scan is made constant.

In addition, in the above embodiment, the pitch of the vertical scanning deflection electrode 11,
Although the linearity of vertical scanning is improved by changing the width, it goes without saying that the pitch and spacing of the vertical scanning deflection electrodes 11 or the width and spacing may be changed.

A second embodiment of the present invention will be described below with reference to FIG. FIG. 2 is a voltage waveform diagram showing a partial vertical section of the flat panel image display device and voltages applied to the vertical scanning deflection electrodes, similar to the first embodiment. In Figure 2,
The electron gun that generates the electron beam has a back electrode 16, a linear cathode 17, a G1 electrode 18, and a G1 electrode 1, as in the conventional example.
9 and a focusing electrode 20, and a predetermined voltage is applied to each of the vertical scanning deflection electrodes 11a to 11n.

The operation of the above configuration will be explained. First, an electron beam 21 generated from an electron gun travels between the vertical scanning deflection electrode 11 and the shield electrode 13 in the vertical direction.

Here, when the electron beam 21 is made to travel straight, the shield electrode 13 and the vertical scanning deflection electrode 11 are set to the same potential (E,...), and the operation of deflecting the electron beam toward the shield electrode 13 and performing vertical scanning is basically Although the second embodiment is the same as the conventional example, the deflection position of the electron beam 21 is corrected by changing the deflection voltage EBO every horizontal scanning period. In addition, FIG. 2 shows the focusing electrode 2 as in the first embodiment.
2 shows a voltage waveform applied to each vertical scanning deflection electrode 11 when the voltage applied to the shield electrode 13 is higher than the voltage applied to the shield electrode 13. That is, a voltage approximately concave to the shield electrode 13 is applied to the vertical scanning deflection electrode 11n closest to the focusing electrode 20, and a voltage substantially concave to the shield electrode 13 is applied to the vertical scanning deflection electrode 11n located at the top.
A voltage whose maximum value is Eeo and decreases by ΔE every horizontal scanning period is applied to a. Next vertical scanning deflection voltage i at the top
A voltage of EBP for one horizontal scanning period after the start of vertical scanning is applied to llb, and when moving to the next horizontal scanning, (EBO-△E
flN, ), and in the next horizontal scan (EBo−△E
A voltage of B, 2)... is applied. The vertical scanning deflection electrode 11C has two horizontal scanning periods after the start of vertical scanning,
EBP voltage is applied, and during 3 horizontal scans (E, 0-
A deflection voltage of ΔEB, , ) is applied.

In this way, the deflection voltage (F, n
By changing o), the angle at which the electron beam 21 is deflected can be made constant, and the linearity of vertical scanning of the electron beam 21 scanning over the shield electrode 13 is improved. Note that the numerical values of ΔF, BN, ΔEBNi, etc. are determined by the electrode configuration dimensions and other operating voltages.

Effects of the Invention As described above, the effect of the present invention is that by changing the pitch, width, and interval of the vertical scanning deflection electrodes, the linearity of vertical scanning can be improved.

Furthermore, by changing the deflection voltage applied to the vertical scanning deflection electrode every horizontal scanning period, it is possible to improve the linearity of vertical scanning.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a vertical scanning section of a flat panel image display device according to a first embodiment of the present invention, and FIG. 2 is a sectional view of a vertical scanning section of a flat panel image display device according to a second embodiment of the present invention. 3 is a perspective view showing the internal electrode structure of a conventional flat panel image display device, and FIG. 4 is a diagram of the conventional flat panel image display device shown in FIG. 3. FIG. 5 is a vertical cross-sectional view of the device, FIG. 5 is a horizontal cross-sectional view, and FIG. 6 is a timing chart of voltage waveforms applied to the vertical scanning deflection electrodes of the conventional flat panel image display device of FIG. DESCRIPTION OF SYMBOLS 11... Vertical scanning deflection electrode, 13... Shield electrode, 16... Back electrode, 17... Linear cathode, 18
...61'! Pole, 19... G2 electrode, 20... Focusing electrode, 21... Electron beam.

Claims (3)

[Claims] (1) A light-emitting section made of at least a phosphor in a vacuum envelope, a vertical scanning deflection electrode divided in a predetermined direction and arranged at a position facing the light-emitting section with a space in between, and a light-emitting section and An electron gun that generates an electron beam is disposed at a position on the extension of the space between the vertical scanning deflection electrodes, and the vertical scanning deflection electrodes have varying division pitches, electrode widths, or electrode spacings. A flat panel image display device. (2) A light emitting section made of at least a phosphor in a vacuum envelope, a vertical scanning deflection electrode divided at a predetermined pitch and arranged at a position facing the light emitting section with a space between the light emitting section and the light emitting section. An electron gun that generates an electron beam is arranged at a position on the extension of the space between the vertical scanning deflection electrode and the light emitting section and the vertical scanning deflection electrode, and the vertical scanning deflection electrode is provided with an electron gun that sequentially directs the electron beam toward the light emitting section. 1. A method of operating a flat panel image display device, characterized in that a voltage for deflection and a voltage that changes every horizontal scanning period are superimposed. (3) The flat panel image display device according to claim 1 or 2, wherein the electron gun generates an elongated band-shaped electron beam in the horizontal direction of the screen.