JP2004158469A - El device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL device with good energy efficiency of colored light emission, capable of displaying with high color purity. <P>SOLUTION: The EL device is formed by arranging a red color filter layer 13 at a red color display part, and a green color filter layer 14 at a green color display part, and laminating a blue/red color conversion layer 15 on the red color filter layer 13 and a blue/green color conversion layer 16 on the green color filter layer 14, on the back surface of a glass base board, where, neither color filter layer nor color conversion layer is arranged on a blue color display part. In order to make those display parts correspond to light emitting areas, a transparent electrode 18 is arranged in front of an organic light-emitting layer 19 emitting blue light, and a back surface electrode 20 is arranged so as to cross the transparent electrode 18. By the above arrangement, the blue color light generated at the light-emitting area is converted into a red color or a green color by the color conversion layer, and at the light-emitting area where the color conversion layer is not arranged, the blue color is emitted as it is as a blue display light. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to an EL element, and more particularly, to an EL element that performs efficient color display.

Conventionally, there has been an organic EL element made of an organic material as an EL element, and an organic EL element having a configuration as shown in FIG. 17 is known. In this EL device, red (R), green (G), and blue (B) color filters 2 R, 2 G, and 2 B are arranged on the rear surface of a transparent glass substrate 1, and a plurality of front electrodes 4 are provided via a protective film 3. Are arranged in parallel to a predetermined direction, and a plurality of back electrodes 6 are provided orthogonal to the front electrode 4 via the organic light emitting layer 5. The organic light emitting layer 5 has R, G, and B fluorescent materials dispersed randomly and uniformly, and is set so as to generate white light by applying an electric field. 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 recombination of carriers in the organic light emitting layer 5 at the dot portion where both electrodes intersect. The position is set so as to be incident on the filter.

In the above-described conventional organic EL element, since color display is performed using each of the R, G, and B color filters, the emission color of the organic light emitting layer 5 must necessarily be white. In the body, since the R fluorescent 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 white light. Since the components in the wavelength region other than the wavelength region are substantially absorbed, the luminance of the display light emitted from the color filter is considerably lower than the luminance of 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.
In addition, the organic EL device includes an organic EL element provided on a support substrate, a transparent glass substrate bonded so as to sandwich the organic EL element between the support substrate, and a phosphor layer formed on the transparent glass substrate. It is disclosed that the light emitting device emits multicolor light (see Patent Document 1).
JP-A-8-222369

In the structure described in Patent Literature 1, the electrode of the organic EL element on the phosphor layer side must be a transparent electrode in order to make the light of the organic EL element incident on the phosphor layer. Since the transparent electrode has a high work function and is inferior in electron injection property, it must be used as an anode, and the cathode is necessarily disposed on the supporting substrate side. That is, after the cathode is formed on the supporting substrate, the light emitting layer and the transparent anode are sequentially formed. By the way, the cathode has a lower work function and has a higher electron injection property and tends to be easily oxidized.Therefore, the cathode may be oxidized by oxygen and water contained in the atmosphere during the process of forming the light emitting layer and the transparent anode. However, there has been a problem that electrons are not injected into the oxidized cathode and the light emitting area is reduced.
The problem to be solved by the present invention lies in what kind of measures should be taken to obtain an organic EL element which can emit light satisfactorily and display with high color purity.

  The invention according to claim 1, wherein a transparent electrode is formed on the front surface of the organic light emitting layer, and a plurality of light emitting regions are formed on the back surface of the organic light emitting layer opposite to the transparent electrode with the organic light emitting layer interposed therebetween. An electrode is formed, and a color conversion layer that performs wavelength conversion of light generated in an organic light emitting layer in a predetermined light emitting region of the light emitting region and transmits the converted light is located in the predetermined light emitting region. A color filter layer that restricts the 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, and is disposed on one surface of the substrate. And a color filter layer, the color conversion layer, a protective film covering the back surface of the color conversion layer, the transparent electrode, the transparent electrode, the organic light emitting layer, and the back electrode.

  According to the first aspect of the present invention, a color filter layer and a color conversion layer are arranged on one surface of the substrate, and an organic light emitting layer for irradiating the color conversion layer with light is arranged above the color filter layer and the color conversion layer. , The organic light emitting layer is located on the substrate side, and the back electrode is located on the opposite side of the organic light emitting layer from the substrate. For this reason, a filter layer, a color conversion layer, a transparent electrode, an organic light emitting layer, and a back electrode can be formed in this order on the substrate, that is, the atmosphere during the manufacturing process of the light emitting layer and the transparent anode contains oxygen and water. Even after that, since the back electrode is formed later, the back electrode is hardly oxidized, and an effect such that light can be emitted well is brought about. The color conversion can be performed by efficiently converting the wavelength of light generated from the light emitting region of the organic 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.

  According to the present invention, it is possible to realize an EL element which can display images with good energy efficiency and high color purity.

Hereinafter, the details of the organic EL device according to the present invention will be described based on embodiments shown in the drawings.
(Embodiment 1)
FIG. 1 is a cross-sectional view showing an embodiment of the 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 the present embodiment can be used as a multicolor display panel.

  Hereinafter, the configuration of the organic EL element 11 will be described with reference to FIG. First, on a rear surface of a transparent glass substrate 12, a red filter layer 13 as a first color filter layer and a green filter layer 14 as a second color filter layer are formed in a predetermined arrangement. The red filter layer 13 and the green filter 14 are set so as to correspond to a light emitting region described later. The red filter layer 13 is a layer that transmits light in the red wavelength region and absorbs light in the other wavelength regions when light containing light in the red wavelength region is incident. The green filter layer 14 is a layer that absorbs light in the other wavelength regions. 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 of the green filter layer 14, a blue-green conversion layer 16 as a photoluminescence layer that absorbs light in the blue wavelength range and emits light in the green wavelength range of a longer wavelength range corresponds. Formed. The protective film 17 is formed flat so as to cover the back surface of the glass substrate 12 on which the color filter layer and the color conversion layer are formed.

なお、本実施形態では、背面電極２０を光反射性を有しかつ有機発光層１９にキャリアを注入し易い性質をもつメタル材料（例えば、ＭｇＩｎ、ＡｌＬｉなど）で形成した。これら背面電極２０と透明電極１８との交差部分の有機発光層１９は、電界が印加されると発光する発光領域となる。上記した青・赤色変換層１５や青・緑色変換層１６は、発光領域と対応する配置となるように設定されている。上記した本実施形態の有機ＥＬ素子１１では、発光領域と青・赤色変換層１５とが平面的に重なる部分と、発光領域と青・緑色変換層１６とが平面的に重なる部分と、発光領域に対して色変換層が重ならない部分と、の３つのドット部分が形成されている。すなわち、発光領域と青・赤色変換層１５とが平面的に重なる部分では、赤色の発光表示を行うことができ、発光領域と青・緑色変換層１６とが平面的に重なる部分では、緑色の発光表示を行うことができ、発光領域に対して色変換層が重ならない部分では青色の発光表示を行うことができる。このため、これら３つのドット部分の発光を制御することにより、自発光多色表示を行うことが可能となる。 Further, on the back surface of the protective film 17, a plurality of transparent electrodes 18 made of ITO are formed in parallel with each other in a predetermined direction. 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. The organic light emitting layer 19 is made of an organic electroluminescent material that generates blue light when an electric field is applied. A plurality of back electrodes 20 are formed on the back surface of the organic generation layer 19 so as to intersect (perpendicularly) the transparent electrode 18. An electron transport layer made of tris (8-hydroxyquinoline) aluminum (hereinafter, Alq3) and a 4,4'-bis (2,2-diphenylvinylene) biphenyl (hereinafter, DPVBi) in order from the organic light emitting layer 19 and the back electrode 20 side. ) A light-emitting layer composed of 96 wt% and 4,4′-bis (2-carbazolevinylene) biphenyl (hereinafter, BCzVBi) 4 wt%, and N, N′-di (α-naphthyl) -N, N′-diphenyl- A hole transport layer made of 1,1'-biphenyl-4,4'-diamine (hereinafter referred to as α-NPD).
The structural formulas of Alq3, DPVBi, BCzVBi, and α-NPD are shown below.

In the present embodiment, the back electrode 20 is formed of a metal material (for example, MgIn, AlLi, or the like) having light reflectivity and having a property of 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 blue / red conversion layer 15 and the blue / green conversion layer 16 are set so as to correspond to the light emitting area. 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, 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 becomes possible to perform self-emission multicolor display.

Next, the operation and operation of the above-described organic EL element 11 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 transmitted through the glass substrate 12 and 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.

  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 / green conversion layer 16, 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. The blue light passes through 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. The green light passes through the glass substrate 12 and is emitted forward as display light. The green filter layer 14 transmits only a specific green wavelength range and absorbs light in other wavelength ranges. However, light incident on the green filter layer 14 is mainly light mainly in the green wavelength range. The light absorption of the green filter layer 14 is small, and the luminance of the display light is high.

  Further, when the transparent electrode 18 and the back electrode 20 are selected such 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, additive color mixture can be performed, and multi-color display or full-color display can be performed. In particular, in the present embodiment, since the emission color of the organic light emitting layer 19 is blue, the energy efficiency can be greatly increased as compared with a conventional RGB light emitting system using white light emission. In the present embodiment, the red filter layer 13 is disposed in the red display dot portion, and the green filter layer 14 is disposed in the green display dot portion. 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 the 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 the blue wavelength range is applied to the back surface of the glass substrate 12 so as to correspond to the light emitting area of the 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 other visible light wavelength ranges is formed, and the other configuration is the same as that of the first embodiment.

  In the present embodiment, the blue light 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. Further, a blue / red conversion layer 15 and a blue / green conversion layer 16 are arranged and formed on the back surface of the first protection film 17A, and a second protection film 17B is formed so as to cover them. Further, 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 as in the first and second embodiments.

  In the present embodiment, the first protective film 17A covering the color filter layer and the second protective film 17B covering the color conversion layer are formed, so that the color filter layers have uniform transmission characteristics. The unevenness generated by setting the thickness to the optimum value can be compensated, the step between the filter layer and the glass substrate 12 can be flattened by the first protective film 17A, and the color conversion layer and the first protective film Since the step difference from 17A can be flattened by the second protective film 17B, the entire element can be flattened. 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 cross-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. On the back surface of the glass substrate 12, a blue / red conversion layer 15 arranged to correspond to the red filter layer 13, a blue / green conversion layer 16 arranged to correspond to the green filter layer 14, Is formed, and the second protective film 17B is formed flat so as to cover the back surface of the glass substrate 12 and these 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, these formation processes can be simplified.

(Embodiment 5)
FIG. 5 is a sectional view showing Embodiment 5 of the 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 layer is formed on the glass substrate 12 and these color conversion layers. Two protective films 17B are formed. A red filter layer 13, a green filter layer 14, and a blue filter layer 21 are respectively arranged at predetermined positions on the second protective film 17B, and a flat second filter layer 13 and a green filter layer 21 are formed on these filter layers and the second protective film 17B. One protection film 17A is formed. 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 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 this embodiment is formed on the front side of a glass substrate 12, as shown in FIG. First, on the front surface of the glass substrate 12, a plurality of back electrodes 20 that are parallel to each other in a predetermined direction are pattern-formed. An organic light emitting layer 19 is formed on the glass substrate 12 and 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 15 and the blue / green conversion layer 16 are arranged at predetermined positions so as to correspond to portions (light emitting regions) where the back electrode 20 and the transparent electrode 18 intersect, respectively. 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 above-described embodiment, a synthetic resin may be used as long as the substrate has electrical insulation.

  In the present embodiment, the organic EL element 11 can be manufactured by repeating the process of sequentially laminating thin films based on 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. . Other operations 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 above-described second embodiment. The other configuration is the same as that of the second embodiment.

  In the present embodiment, by disposing the excitation light filter layer 23 at the forefront of the element, it is possible to prevent the excitation light from being incident on the organic light emitting layer 19 and causing the organic light emitting layer 19 to emit and emit light. it can. By suppressing such excitation and emission, the contrast of the organic EL element 11 can be improved. Further, by preventing the excitation light from entering, it is possible to prevent the color conversion layer, the organic light emitting layer 19 and the like from deteriorating. The other operations, operations, and effects are the same as those in the above-described second embodiment, and a description thereof will not be repeated.

(Embodiment 8)
FIG. 8 is a sectional view showing Embodiment 8 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, a blue / red conversion layer 15 and a blue / green conversion layer 16 are formed so as to be arranged at predetermined positions. A red filter layer 13 is formed on the blue / red conversion layer 15. Further, a green filter layer 14 is formed on the blue / green conversion layer 16. On the other hand, on the back surface of the second glass substrate 25, a plurality of transparent electrodes 18 that 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 face each other, and the light emitting region of the organic light emitting layer 19 is set to correspond to the color conversion layer.

  In the present embodiment, when laminating the first glass substrate 24 and the second 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 a first modification of the eighth embodiment, in which a blue filter layer 21 is disposed at a position corresponding to a light emitting region where no color conversion layer is disposed on the front surface of a first glass substrate 24. The other configuration is the same as that of the eighth embodiment.

(Modification 2)
FIG. 10 is a cross-sectional view showing a second modification. 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.

(Modification 3)
FIG. 11 shows a third modification of the eighth embodiment. In the third modification, a filter layer is provided on the front side of the first glass substrate 24 of the eighth embodiment, and a 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 fourth modification of the eighth embodiment. In the fourth modification, 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 13, the green filter layer 14, and the blue filter layer 21 are arranged on the back surface of the first glass substrate 24, and these are covered with the second protective film 27. The blue / red conversion layer 15 and the blue / green conversion layer 16 are appropriately disposed on the back surface of the second protection film 27, and these conversion layers are covered with the first protection film 26.

(Modification 5)
FIG. 13 is a cross-sectional view showing Modification Example 5 of Embodiment 8. 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, since the excitation light filter layer 23 is disposed at the forefront of the element, excitation light (for example, ultraviolet light) is incident on the organic light emitting layer 19, and excitation and light emission of the organic light emitting layer 19 occur. Can be suppressed. 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)
14 and 15 show a sixth modification 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, and the organic light emitting layer 19 is formed so as to cover the second glass substrate 25 and the back electrode 20. On the front surface of the organic light emitting layer 19, a plurality of transparent electrodes 18 intersecting with the back electrode 20 with the organic light emitting layer 19 interposed therebetween are formed. 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 element 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 that of a certain wavelength and transmits light having a longer wavelength is used as the 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 with the blue / red conversion layer 15 and the blue / green conversion layer 16 in the adjacent dot portions. The other configuration in the present embodiment is the same as that in the first embodiment.

  In the present embodiment, the low-pass filter layer 29 provided in front (on the observer side) of each color conversion layer is set so as to absorb only the blue wavelength band and transmit light of longer wavelengths such as red and green. . The reason for providing this low-pass filter layer 29 is to prevent blue omission in high-luminance display and to improve color purity. In such a configuration, a common layer of red (R) and green (G) is used. 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 region can be easily improved as compared with a band-pass filter.

  As described above, the first to ninth embodiments have been described, but the present invention is not limited to these, and various changes accompanying the gist of the configuration are possible. For example, in each of the above embodiments, the 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.

FIG. 2 is a cross-sectional view showing Embodiment 1 of the organic EL device according to the present invention. Sectional drawing which shows Embodiment 2 of the organic EL element which concerns on this invention. Sectional drawing which shows Embodiment 3 of the organic EL element which concerns on this invention. Sectional drawing which shows Embodiment 4 of the organic EL element which concerns on this invention. Sectional drawing which shows Embodiment 5 of the organic EL element which concerns on this invention. Sectional drawing which shows Embodiment 6 of the organic EL element which concerns on this invention. Sectional drawing which shows Embodiment 7 of the organic EL element which concerns on this invention. Sectional drawing which shows Embodiment 8 of the organic EL element which concerns on this invention. FIG. 19 is a sectional view showing Modification Example 1 of Embodiment 8. FIG. 21 is a sectional view showing Modification Example 2 of Embodiment 8. FIG. 21 is a sectional view showing a third modification of the eighth embodiment. FIG. 19 is a sectional view showing Modification Example 4 of Embodiment 8. FIG. 21 is a sectional view showing Modification Example 5 of Embodiment 8. FIG. 19 is a sectional view showing a modification 6 of the eighth embodiment. FIG. 19 is a sectional view showing a modification 6 of the eighth embodiment. Sectional drawing which shows Embodiment 9 of the organic EL element which concerns on this invention. Sectional drawing which shows a prior art example.

Explanation of reference numerals

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 (2)

  A transparent electrode is formed on the front surface of the organic light emitting layer, and a back electrode that forms a plurality of light emitting regions facing the transparent electrode with the organic light emitting layer interposed therebetween is formed on the back surface of the organic light emitting layer, A color conversion layer that performs wavelength conversion of light generated in an organic light emitting layer of a predetermined light emitting region in the 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. A color filter layer for limiting the 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, and the color filter layer and the color An EL element comprising: a conversion layer; a protective film covering the back surface of the color conversion layer; the transparent electrode; the transparent electrode; the organic light emitting layer;   2. The EL device according to claim 1, wherein the back electrode is formed of a light-reflective metal material.

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