JPS60263982A - Multicolored display panel - 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 Application of the Invention) The present invention relates to a multicolor EL display panel using a thin film EL (electroluminescence) display panel.

(Prior art and its problems) The thin film EL display element that makes up the thin 1% EL display panel is
It is a thin, all-solid-state self-luminous display element, and is used as segment-type or dot matrix-type display devices that are easy to see.

FIG. 1 shows a cross-sectional view of an AC-driven double-insulated thin-film EL display element, which is a typical element structure of a thin-film EL display element.

A transparent electrode 2, a first insulator layer 32, a light-emitting layer 4. Second insulator layer5. It has a structure in which back electrodes 6 are stacked. 1st. The second insulator layers 3 and 5 are Y2O3,5i3N
It is formed of a transparent dielectric film such as i, Ta2es, BaTi0a, etc. Moreover, the light emitting layer 4 is Z n S +Z n S
The base material used is a mixed crystal of Zn8e or ZnS and Zn8e, to which a luminescent center such as Mn or TbF3.8mF3 is added. These insulator layers and light-emitting layers are formed by film-forming methods such as sputtering, vacuum evaporation, MOCVD, and atomic layer epitaxial method (ALE method), and the overall thickness of the constituent films of the device is extremely thin, less than 2 microns. be.

By applying a high voltage between both electrodes of this thin film EL display element, thermionic electrons accelerated by an electric field collide and excite the luminescent center, resulting in electroluminescence. The color of the emitted light is unique to the emission center; for example, Mn emits yellow-orange, Tb emits green, and Sm emits red.

At present, most thin film EL display panels display a single color, but for practical purposes, a full color or multicolor display is desired. As a method for realizing multicolor display on a thin film EL display panel, as shown in FIG.
Imitate 8+! There is a method of patterning the illumination and installing it in parallel. However, there are difficulties associated with patterning the light-emitting layer, and it is not possible to manufacture it at low cost and with a high yield.

Furthermore, as shown in FIG.
Multicolor display is realized by forming a thin film ID L display element consisting of 0 (a layer) and making the intermediate electrode 11f also a transparent electrode. In the figure, 3' and 5/ are the first and second This is an insulating layer.This method takes advantage of the characteristics of thin-film EL display elements, which are transparent thin films, and can display different luminescent colors in the same display area, achieving good display quality. It is.

However, an extreme multilayer structure as shown in FIG. 3 is difficult to manufacture and significantly reduces the yield rate. Furthermore, in thin film EL display elements, many dielectric breakdowns occur at various minute defects at the initial stage of energization. In the case of a normal thin film EL display element structure, this dielectric breakdown is limited to a diameter of several tens of microns, but in the laminated structure shown in Figure 3, the breakdown hole is large and the breakdown often propagates, making it difficult to use as a display panel. A problem arises that makes it unusable.

(Objective of the Invention) The present invention solves the above-mentioned problems associated with the structure and manufacturing of the multi-color EL display panel, thereby achieving low-cost,
Another object of the present invention is to provide a multicolor EL display panel that provides good display quality.

(Structure of the Invention) The multicolor EL display panel of the present invention emits different colors,
and two thin film ELs, at least one of which is substantially transparent.
It consists of a structure in which display panels are stacked.

Indeed, the multicolor EL display panel of the present invention consists of two thin film EL panels.
This is because a translucent liquid substance is sealed in the gap between stacked display piles.

(Detailed Description of the Structure 1) FIG. 4 is a sectional view showing an example of the structure of the multicolor EL display panel of the present invention.

The first thin film EL display panel 30 includes a transparent 1111 substrate 21
Above, number 1. The second insulator layer 23.25 and the light emitting layer 24 are
The transparent electrodes 22 and 26 are sandwiched in a stacked structure. Here, the electrodes 22 and 26 are ITO (TndiumT
In Oxide) and thin gold films, etc., conductive I+! ;
! is formed. In addition, a second thin film EL display panel 30
' is the first one on the substrate 21'. Second insulator layer 23', 25
' and the light-emitting layer 24' are the electrode 22' and the transparent mold 4? l<26
It is laminated in a sandwiched structure. Here, the electrode 22' may be a transparent electrode or a metal electrode such as Mo, depending on the application. Historically, the light-emitting layers 24 and 24' are composed of, for example, Z tl 8 : M n and Zn 8
:TbF:+ and Zn8:8mF:+ and Zn8:TbF'3, which exhibit different luminescent colors, are used.

The thin +11L display element formed on the transparent substrate 21 and the substrate 21' as described above can perform a light emitting display by itself. As shown in Figure 4,
Place the boards on top of each other with the boards facing outward. In addition, in FIG. The second insulator layer may be of a single-car insulation type, in which seven layers and one insulator layer are omitted.

Actually, the method of overlapping two display panels is not necessarily the same as the fourth one.
You don't have to do it as shown. For example, if the dots are large and misalignment is not a problem, a method may be used in which the next substrate is placed on the upper electrode.

By creating an EL display panel with the above structure,
Table 1 can be performed using the EL light emitted from the light emitting layer 24 and the light emitting layer 24'.

Such a multicolor EL display panel of the present invention is manufactured on each substrate separately, and is significantly easier to manufacture than the conventional ones shown in FIGS. 2 and 3, and has high reliability. It doesn't harm your sexuality. Since the gap between the two substrates 21 and 21' is sufficiently smaller than the display image density - Jθmi, for example, even if the present invention is applied to a dot matrix display device with a high M image of about 5 lines/rT1m, no display will occur. It does not compromise quality.

In addition, by inserting translucent oil into the gap between the substrates, it is possible to prevent reflection of the light-emitting layer and improve the brightness and contrast. It is also effective in preventing deterioration caused by moisture.

The multicolor ELL display panel of the present invention may be used not only for dot matrix display, but also for fixed pattern or segment display. The light emitting layer 1 of each light emitting layer can be changed by applied lightning, pressure, driving frequency, pulse width, etc., and an attractive display with variable color can be achieved with high display quality.

Note that the driving of the multicolor ELL display panel of the present invention can be performed completely independently in each thin film EL display panel, but in order to simplify the driving circuit and logic section, , It is more cost-effective to use the electrodes on the scanning side as the electrodes on the upper and lower ETs and the display panel as driving parts.

(Example-1) A transparent lower electrode 9 light-emitting layer made of an ITO sputtered film on a glass substrate, and an insulator layer with a thickness of 04 microns made of two sputtered films of YzOa and 81 a Na.

Single insulated thin film E L with sequentially laminated ITO transparent upper electrodes
Display elements were prepared in which the light-emitting layer was made of Zn8:TbFs and the light-emitting layer was made of ZnS:5rllF3.

The ITO transparent electrode is formed into a 7-segment pattern for displaying numbers. Place this on the outside of the board [ITO
The segment patterns were aligned and the ends were sealed with epoxy resin.

This example is a transparent panel composed of two glass plates, and the Z
nS: Red when 8mF3 section is lit, ZnS:
When the 3 parts of T h F are lit, a green display is obtained, and when both are lit at the same time, a yellow display is obtained. Of course, by adjusting the luminance, the color coordinates can be continuously varied from red to green.

Furthermore, by applying black paint to the back side crow in this embodiment, a vivid display on a black background can be realized.

(Example-2) ITOa light lower electrode on a glass substrate, Y 203
Insulator layer + Zn8: Mn light emitting layer, Y2O3
The sub-IFJEL display panel consists of two insulating layers of Si3N4 and ITO transparent upper electrode, and the light emitting layer is ZnS:TbF.
We created an EL light emitting panel with a motion range of q. I T O'
+l]: Patterned into orthogonal striped denryu with 4 umbrellas d03 pitch. These two panels were aligned and joined using epoxy resin with thin spacers in between, as shown in Figure 4. The gap is 0. t) 5+nm or less, and silicone oil was inserted into this gap. The glass substrate on the small side of the display was coated with black paint to create a black-face ELL display panel.

Each upper electrode is electrically connected to serve as a scanning side stone, a pole,
Each lower electrode was a cheetah side electrode corresponding to each color display.

As a result, a dot matrix display device capable of displaying three colors of dark green, yellow-orange, and yellow-green could be obtained.

(Effect of the invention) As explained in detail, the multicolor ELL of the present invention
With the above configuration, the display panel can realize multicolor display with high display quality, and has the advantage of being easier to manufacture and having higher reliability than conventional multicolor ELL display panels.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the structure of a double-insulated thin film EL display element, FIGS. 2 and 3 are sectional views showing the structure of a conventional multicolor ELL display panel, and FIG. FIG. 2 is a cross-sectional view showing an example of the configuration of a color ELL display panel. 1...Substrate, 2...Transparent electrode, 3.
3'...First insulator layer, 4...Light emitting layer,
5.5'...second insulator layer, 6...back electrode, 7. 8. 9. 10... Luminescent layer,
11... Intermediate electrode, 21... Transparent substrate, 21'... Substrate, 22... Transparent electrode, 22'... Electrode, 23.23'・・・・・・
First insulator layer, 24.24'... Light emitting layer, 25
, 25'...second insulator layer, 26°26'...
...Transparent electrode, 27...-Seal part, 28.
...oil, 30...first thin film EL display panel, 30'...second thin film EL display panel. Agent Patent Attorney 151 Shin Figure 7? Kuni 4th gate

Claims (2)

[Claims] (1) A multicolor EL display with a feature of having a structure in which two 411 or 11 display panels, at least one of which is substantially transparent, emit different luminescent colors and are stacked on top of each other. panel. (2) A multicolor bow display according to claim 1, which is formed by filling a gap between two thin MEI and display panels stacked fN apart with a translucent liquid substance. panel.