JPH07201466A - Multicolor thin film electroluminescence element - Google Patents

Abstract

PURPOSE:To uniformly control visibility angle dependency and to prevent dielectric breakdown due to contact with an upper part electrode and a filter by opposing the color filter of multicolor thin film EL element, with a uniform space, onto the upper part electrode provided in a light outgoing side of a luminous layer. CONSTITUTION:A spacer 9 is inserted into a clearance of an upper part electrode 6 formed in a parallel streak shape on an insulating layer 5 of coating a luminous layer 4, to form the spacer 9 overlapped with on filters 81, 82 formed on a seal glass substrate 7. Thus by fixedly holding a space between the insulating layer 5 and the filters 81, 82, a uniform space can be ensured between the upper part electrode 6 and the filters 81, 82.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter type multi-color thin film electroluminescent (EL) element which is constructed by combining a thin film electroluminescent element which emits light in response to an applied electric field and a color filter.

[0002]

2. Description of the Related Art A multi-color thin-film EL element that displays a multi-color using a thin-film EL element that emits light of a single color is extremely effective for increasing the amount of information. There are the following two methods for colorizing the currently proposed thin film EL element. One is a filter method that separates light emitted from a single light emitting layer by a plurality of color filters to obtain a plurality of light emitting colors, and the other is a light emitting layer of different light emitting colors arranged in a mosaic shape or a stripe shape, It is a non-filter method that obtains a plurality of emission colors.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
As described in Japanese Patent No. 4878, in the non-filter method, fine processing is required when forming a light emitting layer, which complicates the manufacturing process, and since different light emitting layers are used, the luminance / driving voltage There is a problem in that there is a difference in characteristics and aging characteristics, and it is difficult to make the characteristics uniform.

On the other hand, the filter system includes a filter and an EL.
There is a problem that the viewing angle dependence occurs due to the gap between the elements. Therefore, it is necessary to make the gap between the EL element surface and the color filter as small as possible, but if they are brought into close contact with each other, a portion that makes strong contact with a portion that strongly contacts due to the warp of the substrate and fine irregularities on the surface occurs, There is a problem in that there is a difference in the viewing angle dependence, and dielectric breakdown is likely to occur in a strongly contacting portion.

An object of the present invention is to solve the above-mentioned problems, and in a filter type multi-color thin film EL element, the viewing angle dependence can be uniformly controlled, and further, the dielectric breakdown of the EL element due to the strong contact of the color filter. Can be prevented,
An object of the present invention is to provide a color thin film EL element capable of suppressing the occurrence of pixel defects.

[0006]

In order to achieve the above-mentioned object, the present invention comprises a plurality of parallel translucent upper electrodes running in parallel on the upper surface of an insulating layer covering one side of a light emitting layer, In a multi-color thin film EL device in which a filter that selectively transmits light emitted from the light emitting layer by selectively applying a voltage between the upper electrode and the lower electrode on the other side of the light emitting layer is arranged on the upper electrode A light-shielding spacer higher than the height of the upper electrode is interposed between the filter and the insulating layer in the gap between the upper electrodes. The width of the spacer is preferably narrower than the width of the gap between the upper electrodes. It is effective that the spacer is made of an organic substance containing a pigment or a dye.

[0007]

The height of the gap between the filter and the insulating layer below the upper electrode is maintained by interposing a light-shielding spacer having a height higher than the height of the upper electrode in the gap between the upper electrodes, so that the filter surface is directly connected to each pixel. It is possible to face the upper electrode with a minimum constant interval without contacting the upper electrode. As a result, the viewing angle dependence can be made uniform to a minimum, and furthermore, the dielectric breakdown due to the warp of the substrate and the uneven contact due to the fine irregularities on the surfaces of both substrates can be prevented, and the occurrence of pixel defects can be suppressed. Further, the light-shielding spacer prevents light from scattering from each pixel.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A multicolor thin film EL device according to an embodiment of the present invention will be described below with reference to the sectional structural view of FIG. This multi-color thin film EL device is manufactured as follows.
First, a lower electrode layer 2 made of Cr, Ta, Mo, W or the like is formed on a glass substrate 1, and a lower insulating layer 3 made of SiO ₂ , Si ₃ N ₄ is applied in a stripe shape on the lower electrode layer 2. On the light-emitting layer 4
Is formed on the entire surface with ZnS: Mn that generates a single color. Further, an upper insulating layer 5 made of SiO ₂ and Si ₃ N ₄ is covered, and transparent ITO is formed thereon in a stripe shape in a direction orthogonal to the lower electrode to form an upper electrode 6. Both the upper electrode 6 and the lower electrode 2 have a pitch of 0.3 mm and an electrode width of 0.
It is 22 mm, and the intersecting portion thereof becomes a pixel.

On the other hand, in the production of a color filter, a filter material in which red and green pigments are dispersed in a photosensitive resin on the seal glass substrate 7 is used for 1 to 3 μm by a spin coater or the like.
To a thickness similar to that of the above-mentioned pixels by a photolithography method to form a mosaic film having a pitch and a width to form a red filter 81 and a green filter 82. Next, a photosensitive resin in which a black pigment is dispersed is placed on the filter films 81 and 82 (downward in the figure) of each color by a spin coater at 1 to 100 μm.
m, in this embodiment, it is applied to a thickness of about 5 μm, and a spacer 9 higher than the upper electrode 6 is formed between the filter films 81 and 82 of the respective colors by a width of about 60 μm narrower than the pixel interval by the same process as the filter formation. To form.

The monochromatic light-emitting thin film EL element formed on the substrate 1 and the multi-color filter formed on the substrate 7 are overlapped with each other so that the pixel and the mosaic filter film of each color face each other. Inject silicone oil and seal. At this time, the spacers 9 enter the gaps between the upper electrodes 6, but the width is narrower by about 20 μm than the gaps, so that the alignment is easy.

The multi-color thin film EL element having the above-described structure is Zn when a voltage is applied from the power source 10.
Yellow-orange light is emitted from the light emitting layer 4 of S: Mn, and this light is separated into red and green by passing through the color filter 81 or 82, and multicolor emission is performed in any pixel. Also,
The filter section and the thin film EL element are the filter films 81 and 82.
Spacer 9 formed above and existing in the gap between the upper electrodes 6.
Therefore, there is no direct contact, so that the pixel is not damaged at the product stage. Further, since each pixel is independently separated, and the height of the spacer 9 is controlled, a constant space 11 is maintained between the filter portion and the thin film EL element portion.
The viewing angle dependency is greatly improved.

[0012]

As described above, according to the present invention, in a thin film EL element in which a color filter is arranged facing a pixel surface arranged in a matrix on a substrate and light is emitted through this filter, A spacer having a light-shielding property is provided between the filters arranged to face each pixel, and the spacer is interposed in the gap between the upper electrodes, which are one of the electrodes of the pixel, and the uniform gap is provided between the upper electrode and the color filter. The holding of the filter prevents the filter surface from directly contacting the upper electrode. As a result, the pixel surface of the EL element and the filter surface do not come into direct contact with each other, the viewing angle dependence can be made uniform to a minimum, and the insulation caused by the unevenness of the contact due to the warp of the substrate and the fine unevenness of the surfaces of both the elements. Destruction is prevented,
Occurrence of pixel defects is suppressed.

[Brief description of drawings]

FIG. 1 is a sectional view of a multi-color EL device according to an embodiment of the present invention.

[Explanation of symbols]

 1 Glass Substrate 2 Lower Electrode 3, 5 Insulating Layer 4 Light Emitting Layer 6 Upper Electrode 7 Seal Glass Substrate 81 Red Filter Film 82 Green Filter Film 9 Spacer 10 Power Supply

Claims (3)

[Claims] 1. An insulating layer covering one side of a light emitting layer is provided with a plurality of parallel strip-shaped translucent upper electrodes on an upper surface thereof, and is selectively provided between the upper electrode and the lower electrode on the other side of the light emitting layer. When a filter that selectively transmits the light emitted from the light emitting layer when a voltage is applied to the upper electrode is placed on the upper electrode, the height higher than the upper electrode is placed between the insulating layer in the gap between the upper electrodes and the filter. A multi-color thin film electroluminescent device characterized by interposing a high light-shielding spacer. 2. The multi-color thin film electroluminescent device according to claim 1, wherein the width of the spacer is narrower than the width of the gap between the upper electrodes. 3. The multi-color thin film electroluminescent device according to claim 1, wherein the spacer is an organic substance containing a pigment or a dye.