JPS63196191A - image display device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image display device using a plurality of line cathodes as electron beam sources.

2. Description of the Related Art First, a basic configuration example of an image display element used here will be explained with reference to FIG.

This display element consists of, in order from the back to the front, a back electrode 1, a line cathode 2 as a beam source, and vertical focusing electrodes 3, 3 (
Vertical deflection electrode 4, beam flow control electrode 6, horizontal focusing electrode 6
, a horizontal deflection electrode 7, a beam acceleration electrode 8, and a screen plate 9 are arranged, and these are housed inside a flat glass pulp (not shown) which is made into a vacuum.

A line cathode 2 serving as a beam source is stretched horizontally so as to generate an electron beam distributed linearly in the horizontal direction, and a plurality of line cathodes 2 (here, (Only four wires, 2i to 22 are shown) are provided. In this embodiment, it is assumed that 15 pieces are provided. Let's call them 2i~2yo. These wire cathodes 2 are constructed by coating the surface of a tungsten wire with a diameter of 10 to 20 μΦ with an oxide cathode material for thermionic emission. These line cathodes 2A to 2Y are heated so as to generate a thermionic electron beam by passing an electric current through them, and as will be described later, the electron beams are generated sequentially for a certain period of time starting from the line cathode 2I. controlled to emit. The back electrode 1 suppresses generation of electron beams from line cathodes 2 other than the line cathode 2 that is controlled to emit electron beams for a certain period of time, and directs the generated electron beams only in the forward direction. It has the effect of pushing out. This back electrode 1 may be formed by a coating film of a conductive material adhered to the inner surface of the rear wall of the glass pulp. Further, instead of the back electrode 1 and the linear cathode 2, a planar electron beam emitting cathode may be used.

The vertical focusing electrode 3 is a conductive plate 11 having 100 rows of through holes arranged at small intervals in the horizontal direction facing each of the line cathodes 2a to 2yo, and the line cathodes 2 also collect the emitted electron beam. are taken out through the row of through holes 10 and focused vertically. The above through hole 100
The spacing is the same as the slit spacing of the control electrode 6, which will be described later. This results in one line in the horizontal direction (360 pixels).
electron beams are extracted at the same time. In the figure, only one section in the horizontal direction is shown.

A plurality of vertical deflection electrodes 4 are arranged horizontally at intermediate positions between the rows of through holes 10, and conductors 13, 13 are provided on the upper and lower surfaces of the insulating substrate 12, respectively.
' is provided. Then, a vertical deflection voltage is applied between the opposing conductors 13 j 13' to deflect the electron beam in the vertical direction. In this embodiment, the electron beam from one line cathode 2 is vertically deflected to positions corresponding to 16 lines by a pair of conductors 13 and 13'. The 16 vertical deflection electrodes 4 constitute 15 pairs of conductors corresponding to each of the 115 line cathodes 2, and the electron beams are deflected to draw 240 horizontal lines on the screen 9. do.

Next, the control electrodes 6 each have a long line in the vertical direction).
14'ji, and a plurality of conductive plates 16 are arranged in parallel in the horizontal direction at predetermined intervals. In this embodiment, 180 control electrode conductive plates 161L to 15n are provided (only nine are shown in the figure). This control electrode 6 connects each slit 14 to the vertical focusing electrode 3.
The electron beam divided by the 1° through-hole passes through, and the amount of the electron beam passing through is controlled in accordance with the video signal for displaying each picture element. Therefore, if 151L to 16nt-180 conductive plates for the control electrode 6 are provided, 360 pixels can be displayed per horizontal line.

In addition, in order to display images in color, each picture element is R, G.
・Display will be performed using phosphors of three colors B, and each control electrode 6
R, G, and B video signals for two picture elements are sequentially added. In addition, 180 conductive plates 161L to 1 for control electrodes 6
180 sets of video signals for one line (two picture elements per set) are simultaneously applied to each of the 5Hs, and the video for one line is displayed at one time.

The horizontal focusing electrode 6 is composed of a conductive plate 17 having a plurality of vertically long slits 16 (180 slits) facing the slits 14 of the control electrode 6, and collects electrons for each picture element divided in the horizontal direction. Each beam is focused horizontally into a narrow electron beam.

The horizontal deflection electrodes 7 include a plurality of conductive plates 18 arranged vertically on each side of the sulin 16,
It is composed of 18't', each 1 taku 1B, 1B
A six-step horizontal deflection voltage is applied to the screen 9 to deflect the electron beam of each picture element in the horizontal direction.
Above, the two sets of R, G, and H phosphors are sequentially irradiated to emit light.

In this embodiment, the deflection range is two picture elements wide for each electron beam.

The acceleration electrode 8 is composed of a plurality of conductive plates 19 provided horizontally at the same position as the vertical deflection electrode 4.
The electron beam is accelerated to collide with the screen 9 with sufficient energy.

The screen 9 is constructed by applying a phosphor 20 that emits light when irradiated with an electron beam to the back surface of a glass plate 21, and adding a metal back layer (not shown).

The phosphors 2o are provided with two pairs of phosphors of three colors R+G and B for each slit 14 of the control electrode 6, that is, for each horizontally divided electron beam. It is applied in vertical stripes.

In FIG. 1, the broken lines drawn on the screen 9 indicate divisions in the vertical direction that are displayed corresponding to each of the plurality of line cathodes 2, and the two-dot chain lines correspond to each of the plurality of control electrodes 6. Indicates the horizontal division displayed. As shown in an enlarged view in FIG. 4, one section partitioned by these two has R, G, and B phosphors 20 for two picture elements in the horizontal direction.
It has a width of 16 lines in the vertical direction.

For example, the size of one section is 111I in the horizontal direction.
I. The vertical direction is 10++a.

Note that in FIG. 3, the length in the horizontal direction is greatly expanded relative to the length in the vertical direction for clarity.

Further, in this embodiment, only one pair of R, G, and H phosphors 2o are provided for one control electrode 6, that is, one electron beam, for two picture elements, but of course, one picture element The control electrode 5 may be provided with R, G, B for one picture element or three picture elements or more.
Video signals are applied sequentially, and horizontal deflection is performed in synchronization with the video signals.

Problems to be Solved by the Invention However, in the above-mentioned incorrect configuration, the vertical deflection electrode 4
Because the length of the electron beam, that is, the distance that the electron beam passes through the vertical deflection electrode 4 is much longer than the interval between the through holes 1Q of the vertical focusing electrode 3, the beam is diffused and passes through one slit 14 of the control electrode 6. The electron beam passing through the vertical focusing electrode 3
As well as the electron beam passing through the corresponding through hole 10 of
A portion of the electron beam passing through the through hole in the vicinity is also included.

Therefore, on the screen 9, the electron beam is imaged as an aggregate of several beam spots, so the effective horizontal focus diameter of the electron beam becomes large, and as a result, the electron beam is applied in a stripe pattern on the screen. This has the problem that it is impossible to irradiate each phosphor independently, resulting in a significant deterioration of color reproducibility.

In view of the above problems, the present invention prevents the beams separated by the through holes of the vertical focusing electrode from being mixed again, thereby making the effective horizontal focus diameter of the electron beam smaller than the stripe width of the phosphor. However, the present invention aims to provide an image display device having good color reproducibility.

Means for Solving the Problems To achieve this objective, the image display device of the present invention includes:
It consists of a line cathode, vertical focusing electrode, vertical deflection electrode, beam separation electrode, horizontal deflection electrode, and screen arranged in order from the back to the front, and these are housed inside the vacuum of a flat glass bulb. has been done.

Effect: With this configuration, by applying a sufficiently high voltage to the beam separation electrode, the time required for the electron beam to exit the through hole of the vertical focusing electrode and pass through the vertical deflection electrode is shortened. Since the electron beam itself also becomes smaller, the electron beam that passes through one slit in the control electrode is only the electron beam that passes through the corresponding through hole in the vertical focusing electrode.
, the substantial horizontal focus diameter of the electron beam on the screen is reduced, and an image display device with good color reproducibility can be obtained.

EXAMPLE An example of the present invention will be described below with reference to the drawings. FIG. 1 shows the configuration of an image display device in an embodiment of the present invention.

In FIG. 1, 1 is a back electrode, 2 is a line cathode, 3 is a vertical focusing electrode, 4 is a vertical deflection electrode, 6 is a beam current control electrode,
6 is a horizontal focusing electrode, 7 is a horizontal deflection electrode, 8 is a beam acceleration electrode, and 9 is a screen plate. Further, 60 is a beam separation electrode installed between the vertical deflection electrode 4 and the beam flow control electrode 6, and these are housed inside a flat glass pulp (not shown) which is evacuated.

The operation of the image display device configured as described above will be described below.

First, an electron beam distributed horizontally in a strip is generated from the line cathode 2 as a beam source. Next, the vertical focusing electrode 3
When passing through the row of through holes 1Q, the band-shaped electron beam is divided in the horizontal force direction.

Thereafter, the electron beam is diffused while being vertically deflected while passing through the vertical deflection electrode 4. However, as shown in FIG. 4B, if the voltage applied to the beam separation electrode 6o is sufficiently high (in this example, 2 ), the diffusion of the electron beam is not so great that the beam passing through one through hole 10 of the vertical focusing electrode 30 passes through the slits 14 of the plurality of control electrodes 6, but passes through only one slit.

The control electrode 6 controls the amount of passage of the electron beam according to a video signal for displaying each picture element.

Furthermore, the electron beam focused in the horizontal direction by the horizontal focusing electrode 6 is deflected in the horizontal direction by the horizontal deflection electrode T, and sequentially illuminates two sets of R, G, and B phosphors 2o on the screen 9. and emits light. Note that the beam separation electrode 6
If the voltage applied to zero is lowered, the electron beam will be diffused as shown in Figure 4, so care must be taken.

As described above, according to this embodiment, since the electron beam focused by the horizontal focusing electrode 6 is a beam that has passed through the through hole 1o of the only vertical focusing electrode 3, the image formation on the screen 9 is as follows. Since it consists of only a single spot and can be made smaller than each phosphor, an image display device with good color reproducibility can be obtained.

Effects of the Invention As described above, according to the present invention, by providing a beam separation electrode for horizontally dividing an electron beam passing through a vertical focusing electrode into a plurality of electron beams, it is possible to form an image on a screen. can be formed from only a single spot and can be made smaller than the width of each phosphor, so an image display device with good color reproducibility can be obtained.

[Brief explanation of the drawing]

FIG. 1 shows an image display device 2 in an embodiment of the present invention.
... line cathode, 3 ... vertical focusing electrode, 6 ...
...Beam flow control electrode, 10...Through hole, 5
o... Beam separation electrode. Name of agent: Patent attorney Toshio Nakao and one other person
2 Figure (A><8) (20θV)

Claims (1)

[Claims] The screen is divided vertically into a plurality of sections, and a wire cathode stretched horizontally is provided for each vertical section.
A plate-shaped vertical focusing electrode having a row of through holes in the horizontal direction facing each of the line cathodes is provided, and a beam separation electrode is provided for dividing the incident electron beam into a plurality of electron beams in the horizontal direction, Vertical and horizontal deflection electrodes are provided to vertically and horizontally deflect each split electron beam, and a beam separation electrode is provided behind the vertical deflection electrode to prevent the split electron beams from mixing again during vertical deflection. An image display device comprising: