JPH10162958A - El element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic EL element with high energy efficiency of color luminescence and capable of displaying high color purity. SOLUTION: A red filter layer 13 is arranged in a red display part and a green filter layer 14 is arranged in a green display part, a blue/red conversion layer 15 is stacked on the red filter layer 13 and a blue/green conversion layer 16 is stacked on the green filter layer 14 on the back surface of a glass substrate 12. The color filter layer or the color conversion layer is not arranged in a blue display part. A transparent electrode 18 is formed along the specified direction on the front surface of an organic luminescent layer 19 which performs blue luminescence so that a luminescent region corresponds to the display part, and a back electrode 20 is formed on the back surface so as to cross to the transparent electrode 18. By constituting like this, a blue light generated in a luminescent region is converted into red or green light in a color conversion layer, and in the luminescent region where a corresponding color conversion layer is not arranged, a green light is generated as a display light as it is.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an EL device, and more particularly, to an EL device for performing efficient color display.
Related to the element.

[0002]

2. Description of the Related Art Heretofore, as an EL element, there is an organic EL element made of an organic material, and a structure as shown in FIG. 17 is known. This EL element has a color filter 2 of red (R), green (G) and blue (B) on the rear surface of a transparent glass substrate 1.
R, 2G, and 2B are arranged, a plurality of front electrodes 4 are arranged in parallel with a predetermined direction via a protective film 3, and a plurality of back electrodes 6 orthogonal to the front electrode 4 via an organic light emitting layer 5 are provided. Configuration. This organic light emitting layer 5 has R,
The G and B fluorescent materials are randomly and uniformly dispersed, and are set to generate white light when an electric field is applied. Further, the arrangement is such that the dot portions where the front electrode 4 and the rear electrode 6 intersect correspond to the color filters 2R, 2G, and 2B, respectively. That is, when an electric field is applied between the front electrode 4 and the back electrode 6, light emission occurs due to the recombination of carriers in the organic light emitting layer 5 at the dot portion where both electrodes intersect. It is positioned so as to enter the filter.

[0003]

The above-mentioned conventional organic E
In the L element, color display is performed using each of the R, G, and B color filters, so that the emission color of the organic light emitting layer 5 must be white inevitably. Since the material and the G fluorescent material are mixed,
There is a problem that it is difficult to obtain good conversion efficiency because the probability of causing a non-radiative transition is high. In the method of generating R, G, and B light by passing white light through a color filter, in principle, each of the R, G, and B color filters has a wavelength range of R, G, and B of the white light. Since components in the wavelength range other than the wavelength range are almost absorbed,
The brightness of the display light emitted from the color filter was considerably lower than the brightness of the light emitted from the organic light emitting layer 5. For these reasons, it was extremely difficult for the organic EL device shown in FIG. 17 to realize a display with high energy efficiency. The problem to be solved by the present invention is
The point is what kind of measures should be taken to obtain an organic EL device that can display images with good energy efficiency and high color purity.

[0004]

According to the first aspect of the present invention,
A transparent electrode is formed on the front surface of the light emitting layer, and a back electrode that forms a plurality of light emitting regions facing the transparent electrode with the light emitting layer interposed therebetween is formed on the back surface of the light emitting layer, and A color conversion layer that converts the wavelength of light generated in the light emitting layer of the predetermined light emitting region and transmits the converted light is disposed so as to correspond to the front of the transparent electrode located in the predetermined light emitting region, and the color A color filter layer for limiting a transmission wavelength range of the converted light is disposed in front of the conversion layer so as to correspond to the color conversion layer.

According to the first aspect of the present invention, color conversion can be performed by efficiently converting the wavelength of light generated from the light emitting region of the light emitting layer by the color conversion layer. Further, since the color filter layer is disposed in front of the color conversion layer, an effect of increasing the color purity of the color-converted light can be achieved. Therefore, an EL element with high energy efficiency and high color purity can be realized.

The invention according to claim 2 is characterized in that a plurality of color conversion layers corresponding to the light emitting areas are provided according to a plurality of types of colors. The invention according to claim 3 is characterized in that the color conversion layer converts the wavelength of light incident from the light emitting layer in the light emitting region to a longer wavelength side. In the invention according to claim 4, light emitted by the light emitting layer is blue light,
The color conversion layer has two types, a first conversion layer that converts blue light into red light and a second conversion layer that converts blue light into green light, and the light emitting region where the color conversion layer is not disposed is provided. A first color filter layer that exists and transmits only red light in a specific wavelength range is disposed so as to correspond to the first conversion layer, and only green light in a specific wavelength range is transmitted so as to correspond to the second conversion layer. A second color filter layer that transmits light is disposed, and a third filter layer that transmits only blue light in a specific wavelength range is disposed in front of the light emitting region where the color conversion layer is not disposed correspondingly. And

According to the invention described in claims 2 to 4,
E capable of multi-color display and energy-efficient display
An L element can be realized.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of an organic EL device according to the present invention will be described below based on embodiments shown in the drawings. (Embodiment 1) FIG. 1 is a sectional view showing an embodiment of an organic EL device according to the present invention. In the present embodiment, the present invention is applied to an organic EL element in which light emitting regions of an organic light emitting layer are arranged in a matrix. In the light emitting region, a red light emitting portion that emits red light, a green light emitting portion that emits green light, and a blue light emitting portion that emits blue light are arranged adjacent to each other in a predetermined arrangement. Is configured.
For this reason, the organic EL element of this embodiment can be used as a multicolor display panel.

The structure of the organic EL element 11 will be described below with reference to FIG. First, on the back of the transparent glass substrate 12,
A red filter layer 13 as a first color filter layer;
A green filter layer 14 as a color filter layer is formed in a predetermined arrangement. Note that these red filter layers 1
3 and the green filter 14 are set so as to correspond to a light emitting area described later. The red filter layer 13 is a layer that transmits light in the red wavelength range and absorbs light in other wavelength ranges when light containing light in the red wavelength range is incident. The green filter layer 14 is a layer that absorbs light in the other wavelength ranges. When light containing light is incident, the layer transmits light in the green wavelength range and absorbs light in other wavelength ranges. A blue-red conversion layer 15 as a photoluminescence layer that absorbs light in the blue wavelength range and emits light in the red wavelength range of a longer wavelength range is bonded to the back surface of the red filter layer 13 so as to correspond thereto. It is formed.
On the back surface of the green filter layer 14, a blue-green conversion layer 16 serving as a photoluminescence layer that absorbs light in the blue wavelength range and emits light in the longer wavelength green range.
Are formed so as to correspond to each other. The glass substrate 1 on which these color filter layers and color conversion layers are formed
The protective film 17 is formed flat so as to cover the back surface of the second substrate 2.

Further, on the back surface of the protective film 17, a plurality of transparent electrodes 18 made of ITO are formed in a predetermined direction in parallel with each other. The transparent electrode 18 is set so as to planarly overlap with the blue / red conversion layer 15 and the blue / green conversion layer 16 in a predetermined row. Further, an organic light emitting layer 19 is formed on the back side so as to cover the protective film 17 and the transparent electrode 18. This organic light emitting layer 19
An organic electroluminescent material that generates blue light when an electric field is applied is used. A plurality of back electrodes 20 are formed on the back surface of the organic generation layer 19 so as to intersect (orthogonal) with the transparent electrode 18. The organic light emitting layer 19 and the tris (8-hydroxyquinoline) aluminum (hereinafter referred to as Al)
q3) and 4,4'-bis (2,2-diphenylvinylene) biphenyl (hereinafter referred to as DPVBi) 96
wt.% and 4,4'-bis (2-carbazolevinylene) biphenyl (hereinafter referred to as BCzVBi) 4 wt%, and N, N'-di (α-naphthyl) -N, N'-diphenyl-1 , 1'-biphenyl-4,4'-diamine (hereinafter referred to as α-
A hole transport layer made of NPD).
Below, Alq3, DPVBi, BCzVBi, α-NP
The structural formula of D is shown.

Embedded image

Embedded image

Embedded image

Embedded image In the present embodiment, the back electrode 20 is formed of a metal material (for example, MgIn, AlLi, or the like) having a property of reflecting light and easily injecting carriers into the organic light emitting layer 19. The organic light emitting layer 19 at the intersection of the back electrode 20 and the transparent electrode 18 becomes a light emitting region that emits light when an electric field is applied. The above-described blue / red conversion layer 15 and blue / green conversion layer 16 are set so as to have an arrangement corresponding to the light emitting region. In the above-described organic EL element 11 of the present embodiment, a portion where the light emitting region and the blue / red color conversion layer 15 planarly overlap, a portion where the light emitting region and the blue / green color conversion layer 16 planarly overlap, And a portion where the color conversion layers do not overlap with each other. That is, a red light emission display can be performed in a portion where the light emitting region and the blue / red conversion layer 15 planarly overlap, and a green light is displayed in a portion where the light emitting region and the blue / green conversion layer 16 planarly overlap. Light-emitting display can be performed, and blue light-emitting display can be performed in a portion where the color conversion layer does not overlap with the light-emitting region. Therefore, by controlling the light emission of these three dot portions, it is possible to perform self-emission multicolor display.

Next, the operation of the above-described organic EL element 11 will be described.
The operation will be described. First, when the transparent electrode 18 and the back electrode 20 are selected so that light emission occurs in the light emitting region corresponding to the blue / red conversion layer 15, an electric field is applied to the light emitting region of the organic light emitting layer 19, Blue light is generated in the light emitting region. This blue light passes through the transparent electrode 18 and the protective film 17 and enters the blue / red conversion layer 15.
This blue light is absorbed by the blue / red conversion layer 15, and the blue / red conversion layer 15 newly generates red light. The red light is transmitted through the red filter layer 13 to increase the color purity of the red light. This red light is applied to the glass substrate 12
And is emitted forward as display light. The red filter layer 13 transmits only a specific red wavelength range and absorbs light in other wavelength ranges. However, light incident on the red filter layer 13 is mainly light mainly in the red wavelength range. The light absorption of the red filter layer 13 is small, and the luminance of the display light is high.

Further, the transparent electrode 18 and the back electrode 20 are so formed as to emit light in a light emitting region corresponding to the blue / green conversion layer 16.
When is selected, an electric field is applied to the light emitting region of the organic light emitting layer 19, so that blue light is generated in the light emitting region. This blue light is transmitted to the transparent electrode 18 and the protective film 17.
And enters the blue / green conversion layer 16. This blue light is absorbed by the blue / green conversion layer 16, and the blue / green conversion layer 16 newly generates green light. This green light is transmitted through the green filter layer 14 to increase the color purity of green. This green light passes through the glass substrate 12 and is emitted forward as display light. Green filter layer 14
Transmits only a specific green wavelength range and absorbs light in other wavelength ranges. However, since the light incident on the green filter layer 14 is mainly light mainly in the green wavelength range, the green filter layer The light absorption of No. 14 is small, and the brightness of the display light is high.

Further, when the transparent electrode 18 and the back electrode 20 are selected so that light emission occurs in a light emitting region where a color conversion layer is not arranged correspondingly, an electric field is applied to the light emitting region of the organic light emitting layer 19. As a result, blue light is generated in the light emitting region. The blue light passes through the transparent electrode 18, the protective film 17, and the glass substrate 12, and is emitted forward as display light. In each dot portion, even if blue light is emitted toward the back electrode 20 side, the back electrode 20 itself has light reflectivity, so that the blue light can be reflected forward and the light utilization efficiency can be improved. Can be increased.

In the present embodiment, by controlling the color display of the above-mentioned three dot portions, it is possible to perform additive color mixture and to perform multi-color display or full-color display. In particular, in this embodiment, since the emission color of the organic light emitting layer 19 is blue, the RG using the conventional white light emission is used.
Energy efficiency can be greatly increased as compared with the B light emitting system. Further, in the present embodiment, by disposing the red filter layer 13 in the red display dot portion and the green filter layer 14 in the green display dot portion, the luminance of blue light emission is temporarily increased, so that the light passes through each color conversion layer. Even when blue light is generated, the red filter layer 13 and the green filter layer 14 are arranged, so that these filters can absorb the blue light. For this reason, in these portions, blue light is not visually recognized by a viewer who views the display, and a display with high color purity can be performed.

(Embodiment 2) FIG. 2 is a sectional view showing Embodiment 2 of an organic EL device according to the present invention. The configuration of the organic EL element 11 of the present embodiment is such that light in a blue wavelength range is applied to the back surface of the glass substrate 12 so as to correspond to a light emitting area of a dot portion where the color conversion layer of the organic EL element 11 is not correspondingly arranged. A blue filter layer 21 that transmits and absorbs light in the other visible light wavelength range is formed, and the other configuration is the same as that of the first embodiment.

In the present embodiment, the blue color emitted from the organic light emitting layer 19 is transmitted through the blue filter layer 21, so that the color purity of blue as display light can be further improved. Other operations and operations are the same as those in the first embodiment.

(Embodiment 3) FIG. 3 is a sectional view showing Embodiment 3 of the organic EL device according to the present invention. In this embodiment, a red filter layer 13, a green filter layer 14, and a blue filter layer 21 are arranged and formed on the back surface of a glass substrate 12, and the first protective film 17A is flat so as to cover the glass substrate 12 and these filter layers. And the first
A blue / red conversion layer 15 and a blue / green conversion layer 16 are arranged and formed on the back surface of the protective film 17A, and a second
A protective film 17B is formed. Further, the second protective film 1
7B, the transparent electrode 18, the organic light emitting layer 19, and the back electrode 2 are provided on the back surface as in the first and second embodiments.
0 is formed.

In this embodiment, a first protective film 17A covering the color filter layer and a second protective film 17B covering the color conversion layer are provided.
By forming the color filter layers, it is possible to compensate for the unevenness generated by setting the thickness of each color filter layer to an optimum value in order to make the transmission characteristics of each color filter layer uniform, and the filter layer and the glass substrate 12 can be flattened by the first protective film 17A, and the step between the color conversion layer and the first protective film 17A can be flattened by the second protective film 17B, so that the entire device can be flattened. it can.
Further, there is an advantage that dimensional accuracy of the color conversion layer can be improved by achieving flattening. Other operations and operations are the same as those in the first and second embodiments.

(Embodiment 4) FIG. 4 is a sectional view showing Embodiment 4 of the organic EL device according to the present invention. In the present embodiment, as shown in the figure, a red filter layer 13, a green filter layer 14, and a blue filter layer 21 are arranged on the front surface of a glass substrate 12, and cover the front surface of the glass substrate 12 and these filter layers. The first protection film 17A is formed flat. Further, on the back surface of the glass substrate 12, a blue / red conversion layer 15 arranged corresponding to the red filter layer 13, a blue / green conversion layer 16 arranged corresponding to the green filter layer 14, Is formed on the glass substrate 1
A second protective film 17B is formed flat so as to cover the back surface of the second and the light conversion layers. On the back surface of the second protective film 17B, a transparent electrode 18, an organic light emitting layer 19, and a back electrode 20 are formed in the same configuration as in the first to third embodiments.

In the present embodiment, since a filter layer and a color conversion layer are formed on the front and back surfaces of one glass substrate 12, the formation process thereof can be simplified.

(Embodiment 5) FIG. 5 is a sectional view showing Embodiment 5 of an organic EL device according to the present invention. In the present embodiment, the blue / red conversion layer 15 and the blue / green conversion layer 16 are formed on the front surface of the glass substrate 12 so as to have a predetermined arrangement, and a flat second conversion layer 15 is formed on the glass substrate 12 and these color conversion layers. Two protective films 17B are formed. This second protective film 1
7B, the red filter layer 13 and the green filter layer 1
4 and a blue filter layer 21 are respectively arranged at predetermined positions, and a flat first protection film 17A is formed on these filter layers and the second protection film 17B. on the other hand,
On the back surface of the glass substrate 12, a transparent electrode 18, an organic light emitting layer 19, and a back electrode 20 are formed in the same configuration as in the above-described first to fourth embodiments.

(Embodiment 6) FIG. 6 is a sectional view showing Embodiment 6 of the organic EL device according to the present invention. The organic EL element 11 of the present embodiment includes a glass substrate 1 as shown in FIG.
2 is created on the front side. First, on the front surface of the glass substrate 12, a plurality of back electrodes 20 which are parallel to each other in a predetermined direction are pattern-formed. In addition, the glass substrate 12
The organic light emitting layer 19 is formed on the back electrode 20. A plurality of transparent electrodes 18 are formed on the organic light emitting layer 19 so as to intersect (orthogonal) with the back electrode 20. Further, a first protective film 22A is formed flat on the organic light emitting layer 19 and the transparent electrode 18. Then, the blue / red conversion layer 1 is arranged so as to correspond to a portion (light emitting region) where the back electrode 20 and the transparent electrode 18 intersect, respectively.
5 and the blue / green conversion layer 16 are arranged at predetermined positions. On the first protective film 22A and the color conversion layers, a second protective film 22B is formed flat. Further, on the second protective film 22B, a red filter layer 13 corresponding to the blue / red conversion layer 15, a green filter layer 16 corresponding to the blue / green conversion layer 16, and a color conversion layer. The blue filter layer 21 is formed so as to correspond to the light emitting region where is not arranged. The third protective film 22C is formed flat on the second protective film 22B and these filter layers.

Although the glass substrate 12 is used in the present embodiment, a synthetic resin may be used as long as the substrate has electrical insulation.

In this embodiment, the organic EL element 11 can be manufactured by repeating the process of sequentially laminating thin films on the basis of the glass substrate 12. Note that any of the above-described first protective film 22A, second protective film 22B, and third protective film 22C may be omitted. According to the present embodiment, since emitted light can be used as display light without transmitting through the glass substrate 12, problems such as deterioration of visibility due to light loss and refraction in the glass can be solved. . The other actions and operations are the same as those in the first embodiment.

(Embodiment 7) FIG. 7 is a sectional view showing Embodiment 7 of the organic EL device according to the present invention. The present embodiment has a configuration in which an excitation light absorption filter layer 23 for preventing incidence of excitation light such as ultraviolet light is disposed on the front surface of the glass substrate 12 of the second embodiment. In addition, other configurations are
This is the same as the second embodiment.

In the present embodiment, the excitation light filter layer 23 is disposed at the forefront of the device, so that excitation light is incident on the organic light emitting layer 19 and excitation and light emission of the organic light emitting layer 19 are suppressed. can do. Such an excitation,
By suppressing light emission, the contrast of the organic EL element 11 can be improved. In addition, by preventing the excitation light from entering, it is possible to prevent the color conversion layer and the organic light emitting layer 19 from deteriorating. The other actions, operations, and effects are the same as those in the above-described second embodiment, and a description thereof will not be repeated.

(Eighth Embodiment) FIG. 8 is a sectional view showing an eighth embodiment of the organic EL device according to the present invention. The configuration of the organic EL element according to the present embodiment will be described with reference to FIG. In the present embodiment, a configuration using two first glass substrates 24 and a second glass substrate 25 is used. First, on the front surface of the first glass substrate 24, the blue / red conversion layer 15 and the blue / green conversion layer 16 are formed so as to be arranged at predetermined positions. The red filter layer 13 is formed on the blue / red conversion layer 15. Further, the blue / green conversion layer 16
On top of this, a green filter layer 14 is formed. On the other hand, on the back surface of the second glass substrate 25, a plurality of transparent electrodes 18 which are parallel to each other along a predetermined direction are formed. An organic light emitting layer 19 is formed on the back side of the second glass substrate 25 and the transparent electrodes 18. further,
On the back surface of the organic light emitting layer 19, a plurality of back electrodes 20 intersecting (perpendicular to) the transparent electrode 18 with the organic light emitting layer 19 interposed therebetween.
Are formed. The rear surface of the first glass substrate 24 and the front surface of the second glass substrate 25 are set so as to face each other, and the light emitting region of the organic light emitting layer 19 corresponds to the color conversion layer and the like.

In this embodiment, the first glass substrate 2
When laminating the fourth glass substrate 25 with the fourth glass substrate 25, a panel bonding technique used in a manufacturing process of a liquid crystal display device can be used. Thereby, in the present embodiment, the first glass substrate 24 and the second glass substrate 25 can be overlapped with an accuracy of about several μm.

(Modification 1) FIG. 9 shows Modification 1 of Embodiment 8, in which a blue filter is provided at a position corresponding to the light emitting area where the color conversion layer on the front surface of the first glass substrate 24 is not arranged. This is a configuration in which the layer 21 is arranged, and the other configuration is the same as that of the eighth embodiment.

(Modification 2) FIG. 10 is a sectional view showing Modification 2. The second modification has a configuration in which the color conversion layer and the filter layer of the first modification are respectively covered with protective films. That is, after the blue / red conversion layer 15 and the blue / green conversion layer 16 are arranged at predetermined positions on the first glass substrate 24, a flat first protective film is formed so as to cover these color conversion layers. 26 are formed. The red filter layer 13, the green filter layer 14, and the blue filter layer 21 are appropriately disposed on the first protective film 26, and the second protective film 27 is formed flat on these filter layers. The other configuration in the second modification, that is, the configuration on the second glass substrate 25 side is the same as that of the eighth embodiment.

(Third Modification) FIG. 11 shows a third modification of the eighth embodiment. In the third modification, the filter layer is provided on the front side of the first glass substrate 24 of the eighth embodiment, and the color conversion layer is provided on the back side. The back side is covered with the first protective film 26, The front side is covered with the second protective film 27.

(Modification 4) FIG. 12 shows a modification 4 of the eighth embodiment. In this modified example 4, a color conversion layer and a color filter layer are provided on the back side of the first glass substrate 24 of the eighth embodiment, and the second glass substrate 25 and the first glass substrate 24 are opposed to each other. This is the configuration. That is, the red filter layer 1 is provided on the back of the first glass substrate 24.
3, a green filter layer 14, and a blue filter layer 21 are arranged, and these are covered with a second protective film 27. The blue / red conversion layer 15 and the blue / green conversion layer 16 are appropriately arranged on the back surface of the second protection film 27, and these conversion layers are covered with the first protection film 26.

(Fifth Modification) FIG. 13 is a sectional view showing a fifth modification of the eighth embodiment. The fifth modification has a configuration in which the excitation light absorption filter layer 23 is disposed on the front surface of the first glass substrate 24 of the fourth modification. In the present embodiment,
By arranging the excitation light filter layer 23 at the forefront of the device, it is possible to suppress excitation light (for example, ultraviolet light) from being incident on the organic light emitting layer 19 and causing excitation and light emission of the organic light emitting layer 19. . By suppressing such excitation and emission, the contrast of the organic EL element 11 can be improved. Further, by preventing the incidence of ultraviolet light, deterioration of the color conversion layer, the organic light emitting layer 19, and the like can be prevented.

(Modification 6) FIGS. 14 and 15 show a modification 6 of the eighth embodiment. The configuration on the first glass substrate 24 side in this modified example 6 is the same as that of the above-described modified example 4, but the configuration on the second glass substrate 25 side opposed thereto is different. That is, a plurality of back electrodes 20 are formed on the front surface of the second glass substrate 25 along a predetermined direction,
The organic light emitting layer 19 is formed so as to cover the second glass substrate 25 and the back electrode 20. Further, the organic light emitting layer 19
Are formed with a plurality of transparent electrodes 18 intersecting the back electrode 20 with the organic light emitting layer 19 interposed therebetween. In order to support the first glass substrate 24 side and the second glass substrate 25 side having such a configuration facing each other, as shown in FIG. 15, the first glass substrate 24 side and the second glass substrate 25 side Are supported with a seal member 28 interposed therebetween. Such a bonding method is possible by using a manufacturing process of a liquid crystal display device. Since the electrodes and the organic light emitting layer 19 can be shielded from the outside air by joining with the use of the sealing material 28 in this manner, deterioration of the element can be suppressed. A nitrogen gas, a rare gas, or silicone oil may be sealed in the interior surrounded by the sealing material 28.

(Embodiment 9) FIG. 16 is a sectional view showing Embodiment 9 of the organic EL device according to the present invention. In the present embodiment, a short-wavelength cut-off optical low-pass filter that absorbs light having a wavelength shorter than a certain wavelength and transmits light having a longer wavelength is used as a filter layer. The configuration of the organic EL element 11 of the present embodiment is such that the red filter layer 13 and the green filter layer 14 in the first embodiment are replaced with a low-pass filter layer 29. The low-pass filter layer 29 is formed on the back surface of the glass substrate 12 so as to overlap both the blue / red conversion layer 15 and the blue / green conversion layer 16 in the adjacent dot portions. In addition,
Other configurations in the present embodiment are the same as those in the first embodiment.

In the present embodiment, the low-pass filter layer 29 provided in front of each color conversion layer (on the observer side) absorbs only the blue wavelength band and transmits red and green light of longer wavelengths. Have been. The reason for providing the low-pass filter layer 29 is to prevent blue omission in high-luminance display and to improve color purity. In such a configuration, the common layer of red (R) and green (G) is used for this purpose. Can be realized. If the blue / green conversion layer 16 does not transmit high-luminance blue light, a low-pass filter layer 29 corresponding to only the blue / red conversion layer 15 may be provided. In general, an optical low-pass filter has an advantage that an absorption edge can be easily designed and a transmittance in a transmission wavelength range can be easily improved as compared with a band-pass filter.

Although the first to ninth embodiments have been described above, the present invention is not limited to these embodiments, and various modifications accompanying the gist of the configuration are possible. For example, in each of the above embodiments, an organic EL material that generates blue light is used as the organic light emitting layer 19, but the present invention is not limited to this, and can be changed as appropriate. Further, the protective film can be omitted as appropriate.

[0038]

As is apparent from the above description, according to the present invention, there is an effect that an EL element having good energy efficiency and capable of performing display with high color purity can be realized.

[Brief description of the drawings]

FIG. 1 is a sectional view showing Embodiment 1 of an organic EL device according to the present invention.

FIG. 2 is a sectional view showing Embodiment 2 of the organic EL device according to the present invention.

FIG. 3 is a sectional view showing Embodiment 3 of the organic EL device according to the present invention.

FIG. 4 is a sectional view showing Embodiment 4 of the organic EL element according to the present invention.

FIG. 5 is a sectional view showing Embodiment 5 of the organic EL device according to the present invention.

FIG. 6 is a sectional view showing Embodiment 6 of the organic EL element according to the present invention.

FIG. 7 is a sectional view showing Embodiment 7 of the organic EL element according to the present invention.

FIG. 8 is a sectional view showing Embodiment 8 of the organic EL device according to the present invention.

FIG. 9 is a sectional view showing a first modification of the eighth embodiment.

FIG. 10 is a sectional view showing Modification Example 2 of Embodiment 8.

FIG. 11 is a sectional view showing a third modification of the eighth embodiment.

FIG. 12 is a sectional view showing a fourth modification of the eighth embodiment.

FIG. 13 is a sectional view showing Modification Example 5 of Embodiment 8.

FIG. 14 is a sectional view showing a modification 6 of the eighth embodiment.

FIG. 15 is a sectional view showing a modification 6 of the eighth embodiment.

FIG. 16 is a sectional view showing Embodiment 9 of the organic EL element according to the present invention.

FIG. 17 is a sectional view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Organic EL element 12 Glass substrate 13 Red filter layer 14 Green filter layer 15 Blue / red conversion layer 16 Blue / green conversion layer 18 Transparent electrode 19 Organic light emitting layer 20 Back electrode 21 Blue filter layer

Claims (4)

[Claims] A transparent electrode is formed on a front surface of the light emitting layer, and a back electrode for forming a plurality of light emitting regions is formed on a back surface of the light emitting layer so as to face the transparent electrode with the light emitting layer interposed therebetween. A color conversion layer that performs wavelength conversion of light generated in a light emitting layer of a predetermined light emitting region and transmits the converted light is disposed in front of the transparent electrode located in the predetermined light emitting region. An EL element, wherein a color filter layer for limiting a transmission wavelength range of the converted light is disposed in front of the color conversion layer so as to correspond to the color conversion layer. 2. The EL device according to claim 1, wherein there are a plurality of types of color conversion layers corresponding to the light emitting regions. 3. The EL device according to claim 1, wherein the color conversion layer converts a wavelength of light incident from the light emitting layer in the light emitting region to a longer wavelength side. 4. The light emitted from the light emitting layer is blue light, and the color conversion layer includes a first conversion layer that converts blue light into red light and a second conversion layer that converts blue light into green light. There are two types, the light-emitting region in which the color conversion layer is not disposed, and a first color filter layer that transmits only red light in a specific wavelength region is disposed so as to correspond to the first conversion layer, A second color filter layer that transmits only green light of a specific wavelength range is disposed so as to correspond to the second conversion layer, and a specific wavelength range is located in front of the light emitting region where the color conversion layer is not disposed correspondingly. The EL device according to claim 2, wherein a third filter layer that transmits only blue light is disposed.