CN101350361B - Electro-luminescence device and electronic apparatus - Google Patents

Abstract

The EL device has R pixels, G pixels, and B pixels. Each pixel has at least a pair of electrodes and a light-emitting layer, and one of the electrodes is a light-transmitting electrode. An insulator laminated film having a plurality of low-refractive-index layers and a plurality of high-refractive-index layers formed of a light-transmitting insulator is formed on the surface of the light-transmitting electrode opposite to the light-emitting layer; High-refractive-index layers and high-refractive-index layers are stacked alternately. Each of the plurality of low-refractive-index layers is formed across the entire light-emitting area of the R, G, and B pixels, and has the same thickness even in an area overlapping with any one of the R, G, and B pixels; Each of the two high-refractive index layers is formed across the entire light-emitting area of the R, G, and B pixels, and has the same thickness even in an area overlapping with any one of the R, G, and B pixels. The multiple low refractive index layers have different thicknesses from each other; the multiple high refractive index layers have different thicknesses from each other. The color purity of the output light can be improved, and the structure is simple and the manufacture is easy.

Description

EL device and electronic equipment

This application is a divisional application of the application with the same name with application number 200510124893.1 (application date: November 22, 2005).

technical field

The present invention relates to EL devices and electronic equipment.

Background technique

In recent years, EL devices having a plurality of electroluminescent (hereinafter referred to as EL) elements have been proposed as components for displaying information in electronic devices such as notebook computers, mobile phones, and electronic notebooks. In the EL element, an EL layer (light emitting layer) is disposed between a pair of opposing electrodes.

In the field of EL devices, generally, a multilayer film in which layers having different refractive indices are alternately stacked is used to resonate light of a specific wavelength. For example, in Patent Document 1, it is proposed to have a semitransparent reflective film made of a dielectric formed on the entire surface of a glass substrate, a spacer made of _SiO2 formed thereon, a transparent anode formed thereon, and a semitransparent film formed thereon. An EL device with a hole injection layer on it, a light emitting layer formed thereon, and a cathode formed thereon. This light-emitting layer is formed of a common material in any pixel and emits white light, but in order to make the output color different as the purpose, the sum of the optical distance between the transparent anode and the hole injection layer and the light-emitting layer or the spacer of _SiO2 The thickness of differs depending on the output color that is the purpose. Therefore, even if the light-emitting layer is formed of the same white light-emitting material, output colors of R (red), G (green), and B (blue) can be obtained.

In addition, Patent Document 2 proposes an EL device including light emitting layers made of different materials for R, G, and B pixels, and a group of translucent reflective layers overlapping all the light emitting layers. The semi-transparent reflective layer group has the same structure for all the light-emitting layers, but for the purpose of improving the color purity of the output color, there are semi-reflective layers suitable for resonance of R light, semi-reflective layers suitable for resonance of G light, and semi-reflective layers suitable for resonance of G light. A semi-reflective layer that resonates with B light. These semi-reflective layers respectively have a plurality of low refractive index layers (such as SiO ₂ layers) and a plurality of high refractive index layers (such as TiO ₂ layers), and these low refractive index layers and high refractive index layers are alternately layered. In each semi-reflective layer, the refractive index n1 of the high refractive index layer, its thickness d1, and the refractive index n2 of the low refractive index layer, its thickness d2 are set to satisfy Expression 1.

n1·d1=n2·d2=(1/4+m/2)·λ...(1)

Here, λ is the wavelength of light to be reflected and resonated, and m is an arbitrary integer of 0 or more. Therefore, in the respective semi-reflective layers, the low-refractive-index layers have the same thickness d2 as each other, and the high-refractive-index layers have the same thickness d1 as each other.

[Patent Document 1] Japanese Patent No. 2797883

[Patent Document 2] Special Publication No. 2003-528421

However, in the EL device of Patent Document 1, it is difficult to improve the color purity of the output light even if it can emit light of different colors from white. In addition, white light-emitting materials having a certain level of light emission intensity are limited in all wavelength regions of R, G, and B.

In addition, in the EL device of Patent Document 2, for example, red light emission of an R pixel is actually largely reflected by a layer suitable for G or B light. Therefore, the luminescence of any color is greatly attenuated when passing through the translucent reflective layer group, and the required resonance effect cannot be obtained. In addition, the light emitted from the light-emitting layer is reflected or transmitted at each interface, and passes through various routes before being output, so it cannot be said that the determination of the thickness of the low-refractive index layer and the high-refractive index layer according to Expression 1 is closely related to a significant resonance effect . The translucent reflective layer group has a semi-reflective layer suitable for resonance of R light, a semi-reflective layer suitable for resonance of G light, and a semi-reflective layer suitable for resonance of B light. Therefore, the number of layers must be large and it is difficult to manufacture.

Contents of the invention

Therefore, the present invention provides an EL device capable of improving the color purity of output light and having a simple structure and easy manufacture.

One aspect of the EL device of the present invention is an EL device having an R pixel capable of emitting light corresponding to red, a G pixel capable of emitting light corresponding to green, and a B pixel capable of emitting light corresponding to blue. The pixel is characterized in that each pixel has at least a pair of electrodes and a light-emitting layer sandwiched between these electrodes and is supplied with electric energy to emit light, one of the electrodes is a light-transmitting electrode; An insulator laminated film is formed on the surface of the photoelectrode opposite to the light-emitting layer; the insulator laminated film has a plurality of low refractive index layers formed of a light-transmitting insulator, and has A plurality of high-refractive-index layers formed by a light-transmitting insulator with a high refractive index, these low-refractive-index layers and high-refractive-index layers are stacked alternately; The entire area of the light-emitting area of the B pixel is formed, and has the same thickness in the area overlapping with any one of the R pixel, the G pixel, and the B pixel; the high refractive index layer spans The light-emitting areas of the R pixel, the G pixel, and the B pixel are all formed in an area overlapping with any one of the R pixel, the G pixel, and the B pixel have the same thickness; a plurality of the low refractive index layers have different thicknesses from each other; a plurality of the high refractive index layers have different thicknesses from each other; determine the thickness of the low refractive index layer and the high refractive index layer , so that if the light-emitting layer emits light, at least due to reflection at the interface between the light-transmitting electrode and the insulator laminated film and the interface between the low-refractive index layer and the high-refractive index layer, At any one of the emission peak wavelengths of the R pixel, the G pixel, and the B pixel, light with higher intensity is emitted from the insulator multilayer film than without the insulator multilayer film.

In the EL device of this aspect, an insulator laminate film in which a plurality of low-refractive-index layers and a plurality of high-refractive-index layers are alternately laminated is disposed on the side of the light-transmitting electrode opposite to the light-emitting layer. By appropriately determining the thicknesses of the low-refractive-index layer and the high-refractive-index layer, if the light-emitting layer emits light, at least due to reflection at the interface between the light-transmitting electrode and the insulator laminated film and the interface between the low-refractive index layer and the high-refractive index layer , at any one of the emission peak wavelengths of the R pixel, the G pixel, and the B pixel, light with a higher intensity is emitted from the insulator laminated film than when there is no insulator laminated film. "Emission peak wavelength" is the wavelength with the highest intensity among the wavelengths of light emitted from the light emitting layer of the pixel. In the present invention, regardless of the peak emission wavelength of the R pixel, the peak emission wavelength of the G pixel, or the peak emission wavelength of the B pixel, high-intensity light is emitted due to the insulator laminated film. Therefore, the color purity of output light can be improved. The plurality of low-refractive-index layers have different thicknesses from each other, but each low-refractive-index layer has the same thickness in an area overlapping with any one of the R pixel, the G pixel, and the B pixel, and the plurality of high-refractive-index layers have the same thickness. Although the thicknesses are different from each other, each high-refractive index layer has the same thickness in a region overlapping with any of the R pixel, G pixel, and B pixel, so there is no need to change the thickness for each pixel. That is, the insulator laminated films overlapping the R pixel, the G pixel, and the B pixel have a common structure. In addition, it is not necessary to separately design a layer suitable for resonance of R light, a layer suitable for resonance of G light, and a layer suitable for resonance of B light.

Another form of the EL device of the present invention is an EL device having an R pixel capable of emitting light corresponding to red, a G pixel capable of emitting light corresponding to green, and a B pixel capable of emitting light corresponding to blue. The pixel is characterized in that each pixel has at least a pair of electrodes and a light-emitting layer sandwiched between these electrodes and is supplied with electric energy to emit light, one of the electrodes is a light-transmitting electrode; An insulator laminated film is formed on the surface of the photoelectrode opposite to the light-emitting layer; the insulator laminated film has a low refractive index layer formed of a light-transmitting insulator, and has an A high-refractive-index layer formed by a light-transmitting insulator of refractive index; the low-refractive-index layer is formed across the entire light-emitting area of the R pixel, the G pixel, and the B pixel, and the R The pixel, the G pixel and the B pixel have the same thickness in any overlapping region; the high refractive index layer spans the R pixel, the G pixel and the B pixel The entire area of the light-emitting area of the pixel is formed, and has the same thickness in the area overlapping with any one of the R pixel, the G pixel, and the B pixel; determine the low refractive index layer and the The thickness of the high refractive index layer, so that when light is incident from the insulator laminated film to the light-transmitting electrode and the light-emitting layer, at least due to the interface between the light-transmitting electrode and the insulator laminated film and the reflection of the interface between the low-refractive-index layer and the high-refractive-index layer, the wavelengths of the R pixel, the G pixel, and the B pixel within ±20 nm of each luminescence peak wavelength The reflectance is lower than the reflectance of other wavelengths within ±50nm of each emission peak wavelength.

In the EL device of this aspect, an insulator laminated film having a low-refractive-index layer and a high-refractive-index layer is disposed on the side opposite to the light-emitting layer of the light-transmitting electrode. By appropriately determining the thicknesses of the low-refractive-index layer and the high-refractive-index layer, when light enters the light-transmitting electrode and the insulator laminated film from the light-emitting layer side, at least the interface between the light-transmitting electrode and the insulator laminated film and the Reflection at the interface between the low-refractive-index layer and the high-refractive-index layer is lower at wavelengths within ±20 nm of each emission peak wavelength than at other wavelengths within ±50 nm of each emission peak wavelength. For example, within ±50 nm of the emission peak wavelength of the R pixel, the reflectance of one wavelength within ±20 nm of the emission peak wavelength of the R pixel becomes the lowest. Accordingly, the color purity of output light can be improved. In this specification, "within ±20 nm" includes wavelengths of +20 nm and -20 nm of the emission peak wavelength, and "within ±50 nm" includes wavelengths of +50 nm and -50 nm of the emission peak wavelength. The low-refractive index layer has the same thickness in a region overlapping with any one of the R pixel, G pixel, and B pixel, and the high-refractive index layer has the same thickness as any one of the R pixel, G pixel, and B pixel. An overlapping area has the same thickness, so there is no need to change the thickness by pixel. That is, the insulator laminated films overlapping the R pixel, the G pixel, and the B pixel have a common structure. In addition, it is not necessary to separately design a layer suitable for resonance of R light, a layer suitable for resonance of G light, and a layer suitable for resonance of B light. Therefore, the EL device has a simple structure and is easy to manufacture.

A combination of the light-transmitting electrode and the layer thickness from the light-transmitting electrode to the light-emitting layer including the light-emitting layer differs depending on the light emission color of the pixel. According to this, even if the insulator laminated film overlapping the R pixel, G pixel, and B pixel has a common structure, the combination of the layer thickness from the light-transmitting electrode to the light-emitting layer is different depending on the light-emitting color of the pixel, Therefore, it is possible to easily obtain appropriate reflection characteristics corresponding to the respective luminescent colors.

Furthermore, the EL device of the present invention is an organic EL device, wherein an intermediate layer for reducing leakage of holes or electrodes from the light emitting layer to the light transmitting electrode is disposed between the light emitting layer and the light transmitting electrode. Accordingly, the position of light emission in the thickness direction within the light emitting layer is different from that without the intermediate layer. For example, compared with when there is no such intermediate layer (hole blocking layer and electron blocking layer) between the light emitting layer and the electrode on both sides of the light emitting layer, when an intermediate layer is provided between the light emitting layer and the translucent electrode, the light emitting layer The light-emitting position in the center shifts toward the intermediate layer and further toward the light-transmitting electrode, and depending on the material and/or thickness of the intermediate layer, light may be emitted at the interface between the light-emitting layer and the intermediate layer. Therefore, by providing an intermediate layer and selecting its material and/or thickness, it is possible to adjust the light-emitting position in the thickness direction in the light-emitting layer, and further adjust the optical distance from the light-emitting position to the insulator multilayer film.

The insulator laminated film has a plurality of low-refractive-index layers and a plurality of high-refractive-index layers which are alternately laminated; the plurality of low-refractive-index layers have different thicknesses from each other; The high refractive index layers have different thicknesses from each other.

Conventionally, in a structure in which light is resonated with an insulator laminated film in which a plurality of low-refractive-index layers and a plurality of high-refractive-index layers are alternately stacked, in general, the low-refractive-index layers have the same thickness as each other, and the high-refractive index The frequency layers have the same thickness as each other, but the inventors of the present invention have found that in such a configuration, it is not necessarily possible to obtain a significant resonance effect. When the plurality of low-refractive index layers have different thicknesses and the plurality of high-refractive index layers have different thicknesses, any light of R, G, and B can resonate and emit light with high energy.

In addition, a color filter is disposed on the light emitting side of the insulator laminated film. By providing the color filter in this way, contrast and color purity can be improved.

An electronic device according to the present invention is characterized in that it includes the EL device according to the present invention as a display unit. According to such an electronic device, a display with high color purity of output light can be realized.

Description of drawings

FIG. 1 is a diagram showing an arrangement structure of a color filter emission type organic EL device according to the present invention.

FIG. 2 is a cross-sectional view of the organic EL device of FIG. 1 .

Fig. 3 is a table showing characteristics of each layer of the organic EL device of the present invention.

Fig. 4 is a schematic diagram showing an example of the path of light emitted from pixels of the organic EL device of the present invention.

Fig. 5 is a graph showing the spectrum of light emitted from a region overlapping with each pixel of the organic EL device of the present invention.

6 is a graph showing the spectrum of light emitted from a region overlapping with each pixel of an organic EL device of a comparative example.

7( a ) is a cross-sectional view showing one step of manufacturing the organic EL device of the present invention, ( b ) is a cross-sectional view showing a step after ( a ), and ( c ) is a cross-sectional view showing a step after ( a ).

8( a ) is a cross-sectional view showing a step after FIG. 7( c ), (b) is a cross-sectional view showing a step after (a), and (c) is a cross-sectional view showing a step after (a).

FIG. 9 is a schematic view showing an example of a path of light caused by vertically incident light in the organic EL device of the present invention.

FIG. 10 is a diagram showing a reflectance spectrum for light perpendicularly incident on the organic EL device from the outside in a region overlapping with an R pixel in the organic EL device of the present invention.

FIG. 11 is a graph showing a reflectance spectrum for light perpendicularly incident on the organic EL device from the outside in a region overlapping with a G pixel in the organic EL device of the present invention.

FIG. 12 is a diagram showing a reflectance spectrum for light perpendicularly incident on the organic EL device from the outside in a region overlapping with a B pixel in the organic EL device of the present invention.

Fig. 13 is a table showing the characteristics of each layer of another organic EL device of the present invention.

Fig. 14 is a table showing the characteristics of each layer of another organic EL device of the present invention.

Fig. 15 is a table showing the characteristics of each layer of another organic EL device of the present invention.

Fig. 16 is a cross-sectional view of Example 3 of the full-color light-emitting organic EL device of the present invention.

17 is a cross-sectional view showing part of a full-color light-emitting inorganic EL device according to Example 4 of the present invention.

Fig. 18(a) is a diagram showing an electronic device of the present invention, (b) is a diagram showing another electronic device of the present invention, and (c) is a diagram showing an electronic device of the present invention.

In the figure: 4—pixel electrode (anode, light-transmitting electrode); 7—luminescent layer; 9—counter electrode (cathode); 16a, 16b, 16c—second interlayer insulating layer (high refractive index layer); 17a, 17b, 17c—second interlayer insulating layer (low refractive index layer); 18—insulator laminated film; 100—organic EL device (EL device); 202—light-transmitting electrode; 204—light-emitting layer; 206—back surface Electrode; 207—insulator laminated film; 208—low refractive index layer; 209—high refractive index layer.

Detailed ways

Various embodiments of the present invention will be described below with reference to the drawings. In these drawings, the dimensional ratio of each layer or each member is suitably different from the actual one.

<Example 1>

A full-color light-emitting organic EL device according to Example 1 of the present invention will be described. FIG. 1 is a diagram showing a wiring structure of an organic EL device 100 , and FIG. 2 is a cross-sectional view of the organic EL device 100 .

As shown in FIG. 1 , an organic EL device 100 has a plurality of scanning lines 101 , a plurality of signal lines 102 extending in a direction intersecting the scanning lines 101 , and a plurality of power supply lines 103 extending in parallel with the signal lines 102 . In the vicinity of intersections of the scanning lines 101 and the signal lines 102, pixel areas form a matrix.

A data-side driver circuit 104 including a shift register, a level shifter, a video line, and an analog switch is connected to the signal line 102 . Furthermore, a scanning-side driver circuit 105 including a shift register and a level shifter is connected to the scanning line 101 .

In each pixel region A, a first thin film transistor 122 for supplying a scan signal to the gate through the scan line 101, a capacitor cap for holding a pixel signal supplied from the signal line 102 through the first thin film transistor 122, and a capacitor cap The held pixel signal is supplied to the gate of the second thin film transistor 2 . In addition, in the pixel region A, the pixel electrode 4 through which the drive current flows from the power supply line 103 when the power supply line 103 is energized by the second thin film transistor 2 is provided, and the pixel electrode 4 and the opposite electrode (cathode) are arranged. 9 between the luminescent layers 7 . An organic EL element is constituted by the pixel electrode 4 , the counter electrode 9 and the light emitting layer 7 .

According to such a structure, when the scanning line 101 is driven and the first thin film transistor 122 is turned on, the potential of the signal line 102 at this time is held by the capacitor cap, and the conduction of the second thin film transistor 2 is determined according to the state of the capacitor cap. and disconnected state. Moreover, the current flows from the power supply line 103 to the pixel electrode 4 through the channel of the second thin film transistor 2 , and the current flows to the opposite electrode 9 through the light emitting layer 7 . The light emitting layer 7 emits light according to the amount of current flowing through it.

As shown in FIG. 2 , the organic EL device 100 has a transparent substrate 1 formed of a translucent material such as glass, and a plurality of organic EL elements 7 a arranged in a matrix on the transparent substrate 1 . Specifically, the organic EL element 7 a has a thin film transistor (TFT) 2 laminated on a transparent substrate 1 , a transparent pixel electrode (transparent anode) 4 , a light emitting layer 7 , and a counter electrode (cathode) 9 .

As the transparent substrate 1, various substrates disclosed such as a silicon substrate, a ceramic substrate, a metal substrate, a plastic substrate, and a plastic film substrate can be used in addition to a glass substrate. On the upper surface of the figure of the transparent substrate 1, a plurality of pixel regions A serving as light emitting regions are arranged in a matrix. Specifically, for color display, pixel regions corresponding to respective colors such as red (R), green (G), and blue (B) are arranged. In each pixel area A, a pixel electrode 4 is arranged, and a signal line, a power supply line, and a scanning line are arranged in the vicinity thereof. In this specification, the pixel area A that can emit red (R) light is called an R pixel, the pixel area A that can emit green (G) light is called a G pixel, and the pixel area A that can emit blue (B) light is called a pixel. ) The pixel area A of the light is called a B pixel.

In addition, a plurality of thin film transistors 2 electrically connected to pixel electrodes (transparent anodes) 4 of the pixel area A are formed on the transparent substrate 1 . The thin film transistor 2 respectively has a semiconductor layer 13 arranged in an island shape on the transparent substrate 1, a gate 12 overlapping with a drain region of the semiconductor layer 13 but separated from the semiconductor layer 13, and a gate region connected to one end of the semiconductor layer 13. The gate 12 is connected to the source 11 on the source region at the other end of the semiconductor layer 13 . The semiconductor layer 13 is formed of a polysilicon film, and the electrodes 10 , 11 , 12 are formed of, for example, aluminum. As described in the disclosed technology, by providing the gate insulating layer 30, the first interlayer insulating layer 31, and the second interlayer insulating layers 16a-16c, 17a-17c, the semiconductor layer 13, the electrodes 10, 11, 12 are configured differently from each other the height of. Specifically, the semiconductor layer 13 is covered by a gate insulating layer 30, the gate electrode 12 arranged on the gate insulating layer 30 is covered by a first interlayer insulating layer 31, and the source electrode 11 arranged on the first interlayer insulating layer 31 is covered by The second interlayer insulating layer 16a covers, and the drain electrode 10 is disposed on the second interlayer insulating layer 17c.

Although not shown in the figure, a gate line connected to the gate 12 is arranged between the insulating layers 30 and 31, and a source line connected to the source 11 is arranged between the insulating layers 31 and 16a as described in the disclosed technology. The various wires shown in FIG. 1 are disposed between any of the insulating layers 30, 31, 16a to 16c, and 17a to 17c. A contact hole 23 for electrically connecting the source electrode 11 and the source region of the semiconductor layer 13 is formed on the insulating layers 30 and 31 . A contact hole 24 for connecting the drain electrode 10 and the drain region of the semiconductor layer 13 is formed on the insulating layers 30, 31, 16a-16c, 17a-17c.

The insulator laminated film 18 has a plurality of low-refractive-index layers formed of a light-transmitting insulator, a high-refractive-index layer formed of a light-transmitting insulator having a higher refractive index than the low-refractive-index layer, and these low-refractive-index layers and high The refractive index layers fall alternately. The second interlayer insulating layers 16a to 16c are high-refractive-index layers formed of, for example, SiN _x or TiO ₂ . The second interlayer insulating layers 17a to 17c are low-refractive-index layers formed of, for example, SiO ₂ . The second interlayer insulating layers 16a-16c, 17a-17c are formed with the same thickness across the entire upper surface of the transparent substrate 1, so they extend across the entire light-emitting area of the R pixel, the G pixel, and the B pixel. Any of overlapping regions of R pixels, G pixels, and B pixels has the same thickness. As will be described later, the plurality of second interlayer insulating layers 16 a to 16 c have mutually different thicknesses, and the plurality of second interlayer insulating layers 17 a to 17 c have mutually different thicknesses.

The gate insulating layer 30 and the first interlayer insulating layer 31 are formed of, for example, SiO ₂ . The gate insulating layer 30 and the first interlayer insulating layer 31 are elements that determine the characteristics of the TFT 2 , and have the same thickness.

The pixel electrode 4 of each pixel region A is formed on the uppermost second interlayer insulating layer 17c of the insulator laminated film 18, and is electrically connected to the drain 10 of the corresponding TFT 2. The pixel electrode 4 is formed of a translucent conductive material such as ITO (Indium Tin Oxide), for example. A hole injection/transport layer 28 is formed on the pixel electrode 4 , an intermediate layer 29 is formed on the hole injection/transport layer 28 , and a light emitting layer 7 is formed on the intermediate layer 29 . The electron injection layer 8 is formed on the entire light-emitting layer 7, and the counter electrode 9 is formed thereon. That is, the electron injection layer 8 and the opposite electrode 9 are common to all pixels, and extend across the entire light-emitting area of the R pixel, G pixel, and B pixel. In this way, the pixel electrode 4 faces the counter electrode 9 with the light emitting layer 7 interposed therebetween, and constitutes an organic EL element (light emitting element) 7 a together with the light emitting layer 7 and the counter electrode 9 .

The hole injecting/transporting layer 28 , the intermediate layer 29 , and the light emitting layer 7 are formed in the concave portion divided by the bank portions 51 , 52 . The first bank portion 51 is made of an inorganic material such as SiO ₂ , and the second bank portion 52 is made of an organic material such as acrylic or polyimide or an inorganic material such as SiO ₂ . The first bank portion 51 is the second interlayer insulating layer 17c, partially covers the outer edge of the pixel electrode 4, and has an opening for disposing the light emitting layer 7 inside. The second dam portion 52 is disposed on the first dam portion 51 and has an opening larger than that of the first dam portion 51 .

The hole injection/transport layer 28 is arranged in each pixel area A, but is made of the same material such as a mixture of 3,4-polyethyleneoxythiophene (PEDOT) and styrenesulfonic acid (PSS) (hereinafter referred to as "PEDOT/PSS") formed. The intermediate layer 29 is also arranged in each pixel region A, but is made of the same material for all pixels. This intermediate layer 29 is to reduce electrons from the cathode to leak from the light-emitting layer 7 to the electron blocking layer of the pixel electrode (anode) 4, such as triphenylamine polymer or TFB (poly(2,7- (9,9-di-n-octylfluorene)-(1,4-phenylene-(4-secbutyphenyl)imino)-1,4-phenylene)) formation.

In the light emitting layer 7, there are red light emitting layer 7R emitting red (R) light, green light emitting layer 7G emitting green (G) light, Blue light emitting layer 7B. The light emitting layer 7 is formed of organic EL materials different for each color.

As described above, the electron injection layer 8 and the counter electrode 9 are common to all pixels. The electron injection layer 8 is formed of, for example, LiF, and has the same thickness in a region overlapping any of the R pixel, G pixel, and B pixel. Although not shown in detail, the counter electrode (cathode) 9 is composed of a calcium layer and an aluminum layer. The side closer to the electron injection layer 8 is an extremely thin second counter electrode layer made of calcium, and the side farther away from the electron injection layer 8 is a thicker first counter electrode layer made of aluminum. The first counter electrode layer and the second counter electrode layer have the same thickness in regions overlapping any of the R pixel, G pixel, and B pixel.

The structure of each light-emitting element of this embodiment is as described above, but as a modification of the light-emitting element that can be used in the present invention, a type without the electron injection layer 8 and an electron injection layer 8 provided between the electron injection layer 8 and the light-emitting layer 7 may be used. The type of the input layer etc. has the type of other layers. For example, when using a low-molecular-based light-emitting layer 7, a type having a cathode, an electron input layer, a light-emitting layer, a hole-transporting layer, a hole-injection layer, and an anode is generally used, and a polymer-based light-emitting layer 7 is often used. Types of anode, light emitting layer, hole injection layer and anode, the present invention can be utilized in these types.

In addition, in this embodiment, the anode is transparent, the cathode is reflective, and the light from the light emitting layer 7 is released to the outside through the pixel electrode 4 and the insulator laminated film 18. However, the anode may be reflective, the cathode may be transparent, and the The present invention is used in a type in which an insulator laminated film 18 is disposed on the transparent cathode side, and light from the light emitting layer 7 is emitted to the outside through the transparent cathode and the insulator laminated film. In addition, the organic EL device 100 of this embodiment is of a bottom emission type in which light from the light emitting layer 7 is emitted to the outside through the substrate 1 . The present invention can also be utilized in a top emission type in which light from the light emitting layer 7 is emitted to the side opposite to the substrate.

As described above, the intermediate layer 29 is an electron blocking layer. Compared with when there is no intermediate layer 29, if there is intermediate layer 29, then in the thickness direction in the light-emitting layer, to intermediate layer 29 and then to the pixel electrode 4 (transparent anode) side displacement, according to the material and And/or the electron blocking performance determined by the thickness, light may be emitted at the interface between the light emitting layer 7 and the intermediate layer 29 . In the present embodiment, the intermediate layer 29 as an electron blocking layer is arranged between the light emitting layer 7 and the transparent anode 4, but in the type in which the anode is reflective and the cathode is transparent, an intermediate layer 29 is arranged between the light emitting layer and the transparent cathode. The intermediate layer of the hole blocking layer. The hole blocking layer is a layer that reduces leakage of holes from the anode from the light emitting layer 7 to the counter electrode (cathode) 9 . If there is a hole blocking layer, then in the thickness direction in the light-emitting layer, it is displaced toward the hole blocking layer and then toward the cathode side, and depending on the hole blocking performance determined by the material and/or thickness of the hole blocking layer, sometimes in the emission layer and the interface of the hole blocking layer emits light. If the intermediate layer is provided on both sides of the light-emitting layer 7, that is, when both the hole-blocking layer and the electron-blocking layer are provided, the light-emitting position in the thickness direction in the light-emitting layer is closer to the one with the higher blocking performance of the hole-blocking layer or the electron-blocking layer. Therefore, by providing at least one intermediate layer and selecting the material and/or thickness, it is possible to adjust the light emitting position in the thickness direction in the light emitting layer, and further adjust the optical distance from the light emitting position to the insulator multilayer film.

FIG. 3 is a table showing the characteristics of each layer of the organic EL device 100 of this embodiment. In FIG. 3, the reason why the refractive index differs depending on the color of the overlapping pixels using the same material is because there is wavelength dependence in the refractive index. The refractive indices shown in FIG. 3 assume that the R pixel emits light of 620 nm, the G pixel emits light of 540 nm, and the B pixel emits light of 470 nm. The optical distance of each layer in FIG. 3 is the product of the thickness of the layer and the refractive index. As shown in FIG. 3, the second interlayer insulating layers 16a to 16c, 17a to 17c in the insulator laminated film 18 have the same thickness in regions overlapping with any of the R pixel, G pixel, and B pixel, respectively. . In addition, the plurality of second insulating interlayers 16a to 16c have different thicknesses from each other, and the plurality of second insulating interlayers 17a to 17c have different thicknesses from each other.

The insulator laminated film 18 has the same structure and the same thickness for all pixels, and the combination of layers from the pixel electrode 4 to the light emitting layer 7 (including the pixel electrode 4 and the light emitting layer 7) depends on the light emission color of the pixel. rather different. The thickness of the pixel electrode 4 is 95 nm in the area overlapping the R pixel, but the thickness of the pixel electrode 4 is 50 nm in the area overlapping the G pixel and the B pixel. The hole injection/transport layer 28 has a thickness of 70 nm in the region overlapping the R and G pixels, but the hole injection/transport layer 28 has a thickness of 30 nm in the region overlapping the B pixel. The thickness of the light-emitting layer 7 varies according to the light-emitting color of the pixel.

FIG. 4 is a schematic diagram showing an example of the path of light emitted from the pixels of the organic EL device 100 of this embodiment. In FIG. 4 , solid lines represent interfaces between layers, and dashed-dotted lines represent paths of light. The illustrated path of light is a representative example, and there are also a plurality of paths of light, but these are omitted for the sake of clarity of the figure. In addition, the angles of the dashed-dotted lines in the figure do not accurately represent the advancing angles of light, and are described as making it easy to distinguish between multiple advancing paths.

FIG. 4 presupposes that the interface BO between the light-emitting layer 7 and the intermediate layer 29 emits light. Light is emitted in all directions from the light emitting position, but at the interface between the reflective counter electrode 9 and the electron injection layer 8 , all light not absorbed by the counter electrode 9 is reflected to the right in the figure. In addition, light is reflected and refracted at the interface between the two transmitted layers. That is, part of the light is reflected at the interface, and the other part is refracted and goes forward. It should be pointed out that when light travels from a substance with a high refractive index (such as the second interlayer insulating layers 16a-16c) to a substance with a low refractive index (such as the second interlayer insulating layers 17a-17c), if the incident angle exceeds a certain angle (critical angle), the phenomenon of total reflection of light at the interface occurs, that is, total reflection, but when light advances from a substance with a high refractive index to a substance with a low refractive index, when the incident angle is smaller than the critical angle (approximately normal incidence), the light is on the interface Reflect only a part, refract the rest, and move forward.

According to the above structure, if the light-emitting layer 7 emits light, the interface between the intermediate layer 29 and the hole injection/transport layer 28, the interface between the hole injection/transport layer 28 and the pixel electrode 4, and the pixel electrode 4 Reflection at the interface between the insulator laminated film 19 and the interface between the low-refractive index second interlayer insulating layers 17a-17c and the high-refractive index second interlayer insulating layers 16a-16c produces a resonance action, and R Pixels, G pixels, and B pixels have any luminous peak wavelength, and the light with higher intensity than when there is no insulator laminated film is from the insulator laminated film 18 to the outside (for the insulator laminated film 18, the opposite side of the light emitting layer 7 is the transparent substrate. Bottom 1 side) release. "Emission peak wavelength" is the wavelength with the highest intensity among the wavelengths of light emitted from the light emitting layer 7 of the pixel. In the present invention, regardless of the luminescence peak wavelength (620nm) of the R pixel, or the luminescence peak wavelength (540nm) of the G pixel, or the luminescence peak wavelength (470nm) of the B pixel, a high-intensity light is released through the insulator laminated film 18. of light. Therefore, the color purity of output light can be improved.

In other words, in this embodiment, the thicknesses of the high refractive index layer (second interlayer insulating layers 16a to 16c) and the low refractive index layer (second interlayer insulating layers 17a to 17c) are determined so that if the light emitting layer 7 emits light, Then, due to the reflection at the interface, at any light emission peak wavelength of the R pixel, G pixel, or B pixel, light with higher intensity than that without the insulator laminate film is emitted from the insulator laminate film 18 to the outside.

First, the premise of the step of determining the thickness of each layer described below will be described. The reflectance R, the transmittance T, the reflection phase change φr, and the transmission phase change φt of the interface between the two layers at normal incidence are obtained by the following expressions (2) to (5). However, _n1 is the refractive index of the medium on the incident side, _n2 is the refractive index of the medium on the outgoing side, and _k2 is the extinction coefficient of the medium on the outgoing side, and the refractive index and extinction coefficient depend on the wavelength of light.

R＝{(n ₁ —n ₂ ) ² +k ₂ ² }/{(n ₁ +n ₂ ) ² +k ₂ ² } ……(2)

T＝4n ₁ n ₂ /{(n ₁ +n ₂ ) ² +k ₂ ² } ……(3)

Φr＝tan ^-1 {2n ₁ k ₂ /(n ₁ ² —n ₂ ² —k ₂ ² )} ……(4)

Φt＝tan ^-1 {k ₂ /(n ₁ +n ₂ )} ……(5)

Using the expressions (2) to (5) and the thickness of each layer, the intensity (amplitude) and phase of the reflected light and the intensity (amplitude) and phase of the transmitted light at each interface perpendicularly incident are obtained, and the insulator multilayer film is estimated to be 18 Intensity (or amplitude) of total light (output light) emitted outward. Then, while changing the thickness of each layer, the intensity (or amplitude) at the emission peak wavelength of the total light emitted from the insulator multilayer film 18 is repeatedly estimated to obtain the optimum thickness of each layer. When estimating the intensity, the light from light emission to up to 3 reflections is totaled. Light reflected more than three times is greatly attenuated due to absorption of light within the layer.

As a condition, the thicknesses of the pixel electrode 4, the hole injection/transport layer 28, and the light emitting layer 7 are varied within a realistic thickness range. Specifically, assuming that ITO is used as the material of the pixel electrode 4, the thickness range is limited to 40 nm to 100 nm. Assuming that PEDOT/PSS is used as a material for the hole injection/transport layer 28, the thickness range is limited to 20 nm to 100 nm. The thickness range of the light-emitting layer 7 is limited to 60nm-100nm. In addition, it is assumed that light is emitted at the interface BO between the light emitting layer 7 and the intermediate layer 29 (see FIG. 4 ).

The intensity at the emission peak wavelength of the total light emitted outward is estimated by simulation using software. Specifically, software available under the trade name "OPTAS-FILM" from Cybernet Systems Co., Ltd. in Tokyo, Japan in August 2005 was used.

(Step 1) Although the purpose is to finally increase the intensity of the light emission peak wavelength of the total light emitted to the outside as much as possible for any of the regions overlapping with the R pixel, G pixel, and B pixel, the insulator The thicknesses of the high refractive index layers (second interlayer insulating layers 16a, 16b, 16c) and low refractive index layers (second interlayer insulating layers 17a, 17b, 17c) of the laminated film 18 are common in any region, Therefore, firstly, in the region overlapping with the G pixel having the emission peak wavelength of almost a central wavelength of about 540 nm in the visible light region, the high refractive index layer 16a, the low refractive index layer 17a, the high refractive index layer 16b, and the low refractive index layer 17b , the thicknesses of the high refractive index layer 16c, the low refractive index layer 17c, the pixel electrode 4G, the hole injection/transport layer 28G, the intermediate layer 29G, and the light emitting layer 7G are optimized. Specifically, while changing the thickness of each layer, repeatedly estimate the intensity of the light emission peak wavelength of the total light emitted from the insulator laminated film 18 to the outside, and combine the thicknesses that emit light with the highest intensity at the light emission peak wavelength as the optimum. Choice of thickness combinations. The refractive index and extinction coefficient depend on the wavelength of light, so at this stage, the optical constants (refractive index and extinction coefficient) for the green wavelength (540 nm) are used. What is obtained in this way is the thickness of each layer with respect to the region overlapping with the G pixel in FIG. 3 .

(Step 2) Next, regarding the region overlapping with the R pixel (emission peak wavelength is about 620nm), fix the thicknesses of the high refractive index layers 16a, 16b, 16c and the low refractive index layers 17a, 17b, 17c to be obtained in step 1. The thicknesses of the pixel electrode 4R, the hole injection/transport layer 28R, the intermediate layer 29R, and the light emitting layer 7R are optimized. Specifically, the thicknesses of the high-refractive-index layers 16a, 16b, 16c and the low-refractive-index layers 17a, 17b, 17c are determined while changing the pixel electrode 4R, the hole injection/transport layer 28R, the intermediate layer 29R, and the light emitting layer. The thickness of the layer 7R is repeatedly estimated at the intensity of the emission peak wavelength of the total light emitted from the insulator laminated film 18 to the outside, and the thickness combination that emits light with the highest intensity at the emission peak wavelength is selected as the optimum thickness combination. At this stage, the optical constants (refractive index and extinction coefficient) for the red wavelength (620 nm) are used. What is obtained in this way is the thickness of each layer with respect to the region overlapping with the R pixel in FIG. 3 .

(Step 3) Next, regarding the region overlapping with the B pixel (emission peak wavelength is about 470nm), the thicknesses of the high refractive index layers 16a, 16b, 16c and the low refractive index layers 17a, 17b, 17c are fixed as determined in step 1. Based on the obtained values, the thicknesses of the pixel electrode 4R, the hole injection/transport layer 28R, the intermediate layer 29R, and the light emitting layer 7R are optimized. Specifically, the thicknesses of the high-refractive-index layers 16a, 16b, 16c and the low-refractive-index layers 17a, 17b, 17c are determined while changing the pixel electrode 4R, the hole injection/transport layer 28R, the intermediate layer 29R, and the light emitting layer. The thickness of the layer 7R is repeatedly estimated at the intensity of the emission peak wavelength of the total light emitted from the insulator laminated film 18 to the outside, and the thickness combination that emits light with the highest intensity at the emission peak wavelength is selected as the optimum thickness combination. At this stage, the optical constants (refractive index and extinction coefficient) for the blue wavelength (470 nm) are used. What is obtained in this way is the thickness of each layer with respect to the area overlapping with the B pixel in FIG. 3 .

As described above, first, the thicknesses of the high-refractive-index layers 16a, 16b, 16c and the low-refractive-index layers 17a, 17b, 17c including the insulator laminated film 18 are determined for the region overlapping with the G pixel, and then the thicknesses of the layers with other pixels are determined. The overlapping regions fix these layers of the insulator multilayer film 18 and determine the thickness of other layers. However, in the optimization step (step 1) of the high-refractive-index layers 16a, 16b, 16c and low-refractive-index layers 17a, 17b, 17c, the region overlapping any pixel of R, G, and B can be determined as the thickness. benchmark. However, if the region overlapping with the G pixel at almost the central wavelength of visible light is taken as a reference as in this embodiment, it is easy to determine the pixel electrode 4R, the hole injection/transport layer 28R, the intermediate layer 29R, and the light emitting layer 7R. With regard to any of the regions overlapping with the R pixel, the G pixel, and the B pixel, high-intensity light is emitted outward.

FIG. 5 is a graph showing the spectrum of light emitted through the transparent substrate 1 from the region overlapping with each pixel of the organic EL device 100 of this embodiment. Fig. 6 is a graph showing the spectrum of light emitted through a transparent substrate from a region overlapping with each pixel of an organic EL device of a comparative example. In these figures, curves distinguished by red, green, and blue represent the frequencies of light emitted from areas overlapping with R pixels, G pixels, and B pixels, respectively. Although not shown, the organic EL device of the comparative example has a transparent substrate made of glass, a single interlayer insulating layer made of _SiNx with a thickness of 600 nm formed thereon, and organic substrates of R, G, and B formed thereon. EL elements. Each organic EL element of the comparative example has a pixel electrode (transparent anode) made of ITO with a thickness of 50 nm formed on the interlayer insulating layer, a hole injection/transport layer made of PEDOT/PSS formed thereon, and a hole injection/transport layer formed on it. The upper intermediate layer (electron blocking layer), the light emitting layer formed thereon, and the reflective metal cathode formed thereon. Regarding organic EL elements of arbitrary colors, the thicknesses of the pixel electrodes, hole injection/transport layers, intermediate layers, and light emitting layers are common.

In FIG. 5, the relative intensity is the frequency of light emitted from the region overlapping with the R pixel, the G pixel, and the B pixel of the organic EL device whose other conditions are the same as those of the present embodiment although there is no insulator laminated film 18. is obtained by dividing the maximum intensity of the light by the intensity of light emitted from the organic EL device 100 of this embodiment. In Fig. 6, the relative intensity is the frequency of the light emitted from the region overlapping with the R pixel, G pixel, and B pixel of the organic EL device with the same other conditions as the comparative example although there is no interlayer insulating layer. The maximum intensity was obtained by dividing the intensity of light emitted by the organic EL device of the comparative example. As can be seen from FIGS. 5 and 6 , according to this embodiment, the intensity of each color is higher and the half-value width of the spectrum is narrower than that of the conventional organic EL device as a comparative example. Therefore, according to the present embodiment, the color purity of output light can be improved.

As described above, according to this embodiment, regardless of the peak emission wavelength of the R pixel, the peak emission wavelength of the G pixel, and the peak emission wavelength of the B pixel, high intensity light can be prevented by the insulator laminated film 18 . Therefore, the color purity of output light can be improved. The plurality of low-refractive-index layers 17a, 17b, and 17c in the insulator laminated film 18 have different thicknesses from each other, but the low-refractive-index layers 17a, 17b, and 17c are respectively in contact with any of the R pixel, G pixel, and B pixel. Since the overlapped area has the same thickness, it is not necessary to change the thickness by pixel. That is, the insulator laminated film 18 overlapping the R pixel, the G pixel, and the B pixel has a common structure. In addition, it is not necessary to separately design layers suitable for the resonance of R light, the resonance of G light, and the resonance of B light. Therefore, the structure of the organic EL device 100 is simple and easy to manufacture.

Conventionally, in a structure in which light is resonated with an insulator laminated film in which a plurality of low-refractive-index layers and a plurality of high-refractive-index layers are alternately laminated, generally the low-refractive-index layers have the same thickness as each other, and the high-refractive index The frequency layers have the same thickness as each other, but the inventors have found that it is not necessarily possible to obtain a significant resonance effect with such a configuration. When the plurality of low-refractive-index layers 17a, 17b, and 17c have mutually different thicknesses and the plurality of high-refractive-index layers 16a, 16b, and 16c have mutually different thicknesses as in this embodiment, any optical resonance of R, G, and B , can be released with high intensity.

In addition, according to this embodiment, the combination of layers from the pixel electrode 4 (light-transmitting electrode) to the light-emitting layer 7 (including the pixel electrode 4 and the light-emitting layer 7) is different according to the light-emitting color of the pixel. Even if the insulator multilayer film 18 in which the pixels, G pixels, and B pixels are stacked has a common structure, it is easy to obtain appropriate reflection characteristics corresponding to the respective luminous colors. Although it is difficult or often complicated to form thin films of different thicknesses according to regions, when using a polymer-based light-emitting layer 7, inkjet can be used to form the hole injection/transport layer 28 and the light-emitting layer 7. As in the method of dropping the liquid material as in the conventional method, the thicknesses of the hole injection/transport layer 28 and the light emitting layer 7 can be easily controlled by appropriately adjusting the amount of the liquid material dropped.

In this embodiment, an intermediate layer 29 serving as an electron blocking layer is provided between the light-emitting layer 7 and the hole injection/transport layer 28, and the intensity of output light is estimated to be based on the distance between the light-emitting layer 7 and the intermediate layer 29. The premise is that the interface BO (see FIG. 4 ) emits light. However, such an intermediate layer may not be provided. When there is no intermediate layer 29 , light is emitted at a balanced position of electrons and holes determined by the characteristics of the hole injection/transport layer 28 , the light emitting layer 7 , and the electron injection layer 8 . For example, when there is no intermediate layer, PEDOT/PSS is used as the hole injection/transport layer 28, and LiF is used as the electron injection layer 8, any pixel emits light not at the interface BO but within the light emitting layer 7. In the R pixel, light is emitted at a position about 30 nm away from the interface BO. Using these luminous positions when there is no intermediate layer, according to the method, the intensity of the output light can be calculated.

An example of a method of manufacturing the organic EL device will be described below.

First, as shown in FIG. 7( a ), an island-shaped semiconductor layer 13 is formed on a previously prepared transparent substrate 1 . Here, the semiconductor layer 13 is formed one by one in each pixel region A (see FIG. 2 ) by photolithography using a polysilicon film.

Next, a gate insulating film 30 is formed on the transparent substrate 1 covering the semiconductor layer 13 . Specifically, SiO ₂ is formed into a film thickness of 75 nm by CVD or other vapor deposition methods. Then, an island-shaped gate 12 is formed on the gate insulating film 30 , that is, on a region of the semiconductor layer 13 overlapping with the channel region. Specifically, the A film is formed by sputtering and patterned by photolithography.

Next, as shown in FIG. 7(b), a first interlayer insulating layer 31 is formed. Specifically, SiO ₂ is formed into a film thickness of 800 nm by CVD or other vapor deposition methods. Next, a contact hole 23 connected to the source region of the semiconductor layer 13 is formed. Specifically, a via hole reaching the source region of the semiconductor layer 13 is formed by mask etching the gate insulating film 30 and the first interlayer insulating layer 31, and a contact hole is formed by filling the via hole with a conductive material such as Al. twenty three. Then, the source electrode 11 connected to the contact hole 23 is formed on the first interlayer insulating layer 31, and then the source electrode 11 is covered to form the second interlayer insulating layer 16a, 16b, 17a, 17b, 16c, 17c.

Next, a contact hole 24 connected to the drain region of the semiconductor layer 13 is formed in the second interlayer insulating layers 16a to 17c. Specifically, a via hole reaching the drain region of the semiconductor layer 13 is formed by mask etching the second interlayer insulating layers 16a to 17c, and the contact hole 24 is formed by filling the via hole with a conductive material such as Al. Then, the pixel electrode 4 connected to the contact hole 24 is formed on the second interlayer insulating layer 17c. Specifically, ITO is formed into a given pattern by a sputtering method. Specifically, the pixel electrode 4 is formed with the above-mentioned optimal film thickness for each color. Specifically, the pixel electrode 4R of the R pixel has a thickness of 95 nm, the pixel electrode 4G of the G pixel has a thickness of 50 nm, and the pixel electrode 4B of the B pixel has a thickness of 50 nm.

Next, as shown in FIG. 8( a ), a first bank portion 51 made of SiO ₂ having an opening 51 a corresponding to each pixel region A (see FIG. 2 ) is formed. Specifically, a SiO ₂ thin film forming step, a photolithography step, and an etching step are performed. The first bank portion 51 is formed so that the peripheral edge portion of the opening portion 51 a overlaps the outer edge portion of the pixel electrode 4 . A second bank portion (partition wall) 52 having an opening 52 a corresponding to each pixel region A is formed on the first bank portion 51 . The second bank portion 52 is polyacrylic resin, and is formed through a step of applying a solution containing polyacrylic resin, a step of drying the applied film, a photolithography step, and an etching step.

Next, as shown in FIG. 8( b ), the liquid composition 61 is disposed on the pixel electrode 4 in the openings 51 a and 52 a formed by the bank portions 51 and 52 . Here, as a disposition method of the liquid composition 61, a known liquid phase method (wet process, wet coating method) is used, for example, a spin coating method, an inkjet (droplet discharge) method, a slit coating method, a dipping method, etc. are used. Coating method, spraying film forming method, printing method. Such a liquid-phase method is suitable for forming a film of a polymer material, and compared with a gas-phase method, an organic EL device can be manufactured inexpensively without using expensive equipment such as a vacuum device. By using such a liquid phase method, a liquid composition 61 is formed on the pixel electrode 4 in each opening 5 .

The liquid composition 61 is obtained by dissolving or dispersing the material for forming the hole injection/transporting layer 28 in the solvent, dissolving or dispersing the material for forming the intermediate layer 29 in the solvent, and dissolving or dispersing the material for forming the light emitting layer (organic EL). The material of layer) 7 is dissolved or dispersed in the solvent. That is, when forming the hole injection/transport layer 28, the intermediate layer 29 and the light emitting layer 7, the liquid composition 61 to be a material of each layer is arranged and dried. As shown in FIG. 8(C), after the hole injection/transport layer 28 is formed, the intermediate layer 29 is formed, and then the light emitting layers 7R, 7G, and 7B of each color are formed.

The hole injection/transport layer 28 is formed with the above-mentioned optimal film thickness for each color. Specifically, the hole injection/transport layer 28R of the R pixel is 70 nm, the hole injection/transport layer 28G of the G pixel is 70 nm, and the B pixel is 70 nm. The hole injection/transport layer 28G of the pixel is 30nm. In addition, the intermediate layer 29 has the above-mentioned optimal film thickness for each color. Specifically, the intermediate layer 29R of the R pixel is 8 nm, the intermediate layer 29G of the G pixel is 8 nm, and the intermediate layer 29B of the B pixel is 8 nm. In addition, the light-emitting layer 7 has the above-mentioned optimal film thickness for each color. Specifically, the light-emitting layer 7R of the R pixel is 96 nm, the light-emitting layer 7G of the G pixel is 90 nm, and the light-emitting layer 7B of the B pixel is 70 nm.

Next, an electron injection layer 8 made of LiF is formed on the entire surface of the transparent substrate 1 (that is, on the light emitting layer 7 and the second partition wall 52 in the opening 5 corresponding to the pixel area) by vacuum evaporation, Further, a counter electrode (cathode) 9 made of Al was formed on the electron injection layer 8 by a vacuum evaporation method, thereby having an organic EL device 100 having the structure shown in FIG. 2 .

<Example 2>

Next, another procedure for determining the thickness of each layer of the organic EL device 100 having the same structure as that of the first embodiment will be described. In this method, assuming that from the outside of the organic EL device 100, from the transparent substrate 1 and the insulator laminated film 18 toward the pixel electrode 4 and the light-emitting layer 7, white light of equal energy is incident vertically, and the images of R, G, and B are vertically incident. The thickness of each layer is determined so that the intensity of reflected light at each emission peak wavelength of the element becomes the minimum. However, the light perpendicularly incident on the organic EL device 100 from the outside is not necessarily limited to equal-energy white light, and the method of determining the thickness of this embodiment is the same as that of R pixels, G pixels, and B pixels in terms of reflectance. It is equivalent that the method of determining the thickness of each layer minimizes the reflectance of each emission peak wavelength. The "reflected light intensity" here refers to the reflected light of the incident light from the insulator laminated film 18 to the pixel electrode 4 and the light emitting layer 7, that is, the intensity of the total output light in the direction from the pixel electrode 4 to the insulator laminated film 18. , "reflectivity" is the ratio of the intensity of reflected light, that is, the total output light in the direction from the pixel electrode 4 to the insulator laminate film 18, to the incident light intensity from the insulator laminate film 18 to the pixel electrode 4 and the light emitting layer 7. According to the determination method, a combination of the same thickness as that of Example 1 (shown in FIG. 3 ) can be obtained, and the color purity of the output light can be improved.

Therefore, in the obtained organic EL device 100, if the light-emitting layer 7 emits light, it passes through the interface between the intermediate layer 29 and the hole injection/transport layer 28, and the interface between the hole injection/transport layer 28 and the pixel electrode 4. interface, the interface between the pixel electrode 4 and the insulator lamination film 18, and the reflection at the interface between the low-refractive-index second interlayer insulating layers 17a-17c and the high-refractive-index second interlayer insulating layers 16a-16c, Resonance occurs, and at any luminescence peak wavelength of R pixel, G pixel, and B pixel, light with higher intensity than when there is no insulator laminated film 18 is outward from the insulator laminated film 18 (for the insulator laminated film 18, the light emitting layer 7, that is, the transparent substrate 1 side) is released. In addition, in the same organic EL device 100, when light is vertically incident on the pixel electrode 4 (light-transmitting electrode) 4 and the light-emitting layer 7 from the side of the insulator laminated film 18, it passes through the intermediate layer 29 and the hole injection/transport layer. 28, the interface between the hole injection/transport layer 28 and the pixel electrode 4, the interface between the pixel electrode 4 and the insulator lamination film 18, and the second interlayer insulating layers 17a to 17c of low refractive index In the reflection of the interface between the second interlayer insulating layers 16a-16c with high refractive index, the reflectance of a wavelength located within ±20nm of each luminous peak wavelength of the R pixel, G pixel, and B pixel is greater than the luminous The reflectance of other wavelengths within ±50 nm of the peak wavelength is still low. For example, when light is vertically incident on the organic EL device 100 from the outside, within the range within ±50 nm of the emission peak wavelength (620 nm) of the R pixel, the reflectance of one wavelength located within ±20 nm of the emission peak wavelength of the R pixel become the lowest.

FIG. 9 is a schematic diagram showing an example of a path of light caused by vertically incident light IL in the organic EL device 100 of this embodiment. In FIG. 9 , a solid line indicates an interface between layers, and a dashed-dotted line indicates a path of light. The illustrated path of light is a representative example, and there are a plurality of paths of light, but these are omitted for simplification of the figure. In addition, the angles of the dashed-dotted lines in the figure do not accurately represent the advancing angles of light, and are described as making it easy to distinguish between multiple advancing paths. As can be seen from FIG. 9 , at the interface between the reflective counter electrode 9 and the electron injection layer 8 , all light not absorbed by the counter electrode 9 is reflected to the right in the figure. In addition, light is reflected and refracted at the interface between the two transmitted layers. As a result, the reflected light from the pixel electrode 4 to the insulator multilayer film 18 exits from the insulator multilayer film 18 to the right in the figure. In this embodiment, the thickness of each layer is determined using the sum of these reflected lights or the ratio of the sum of reflected lights to incident light, that is, the reflectance.

First, the premise of the step of determining the thickness of each layer described below will be described. The reflectance R, transmittance T, reflection phase change φr, and transmission phase change φt of the two layers at normal incidence at the interface are obtained by the following expressions (2) to (5). However, _n1 is the refractive index of the medium on the incident side, _n2 is the refractive index of the medium on the outgoing side, and _k2 is the extinction coefficient of the medium on the outgoing side, and the refractive index and extinction coefficient depend on the wavelength of light.

R＝{(n ₁ —n ₂ ) ² +k ₂ ² }/{(n ₁ +n ₂ ) ² +k ₂ ² } ……(2)

T＝4n ₁ n ₂ /{(n ₁ +n ₂ ) ² +k ₂ ² } ……(3)

Φr＝tan ^-1 {2n ₁ k ₂ /(n ₁ ² —n ₂ ² —k ₂ ² )} ……(4)

Φt＝tan ^-1 {k ₂ /(n ₁ +n ₂ )} ……(5)

Using the expressions (2) to (5) and the thickness of each layer, the intensity (amplitude) and phase of the reflected light at each interface and the intensity of the transmitted light are obtained for the equal-energy white light that is vertically incident on the organic EL device 100 (amplitude) and phase, estimate the intensity (or amplitude) of the total reflected light that is internally reflected and emitted to the outside through the transparent substrate 1 . Then, while changing the thickness of each layer, the estimation of the intensity of the total reflected light emitted from the insulator multilayer film 18 to the outside is repeated to obtain the optimum thickness of each layer. When estimating the intensity, the light from light emission to up to 3 reflections is totaled. Light reflected more than three times is greatly attenuated due to absorption of light within the layer.

As a condition, the thicknesses of the pixel electrode 4, the hole injection/transport layer 28, and the light emitting layer 7 are varied within a realistic thickness range. Specifically, assuming that ITO is used as the material of the pixel electrode 4, the thickness range is limited to 40 nm to 100 nm. Assuming that PEDOT/PSS is used for the material of the hole injection/transport layer 28, the range of the thickness is limited to 20 nm to 100 nm. The thickness range of the light emitting layer 7 is limited to 60nm-100nm.

The intensity of the total reflected light emitted outward is estimated by simulation using software. Specifically, software available under the trade name of "OPTAS-FILM" from Cybernet Systems Co., Ltd. in Tokyo, Japan in August 2005 was used.

(Step 1) Although the purpose is to finally reduce the intensity of reflected light at the emission peak wavelength of the corresponding pixel as much as possible for any of the regions overlapping with the R pixel, G pixel, and B pixel, the insulator layer The thicknesses of the high refractive index layers (second interlayer insulating layers 16a, 16b, 16c) and low refractive index layers (second interlayer insulating layers 17a, 17b, 17c) of the film 18 are common in any region, so First, in the region overlapping with the G pixel having an emission peak wavelength of about 540nm in the visible light region, the high refractive index layer 16a, the low refractive index layer 17a, the high refractive index layer 16b, the low refractive index layer 17b, The thicknesses of the high refractive index layer 16c, the low refractive index layer 17c, the pixel electrode 4G, the hole injection/transport layer 28G, the intermediate layer 29G, and the light emitting layer 7G are optimized. Specifically, while changing the thickness of each layer, repeatedly estimate the intensity of the light emission peak wavelength of the total light emitted from the insulator laminated film 18 to the outside, and combine the thicknesses that emit light with the highest intensity at the light emission peak wavelength as the optimum. Choice of thickness combinations. The refractive index and extinction coefficient depend on the wavelength of light, so at this stage, the optical constants (refractive index and extinction coefficient) for the green wavelength (540 nm) are used. This achieves the same thickness of each layer with respect to the area overlapping the G pixel of FIG. 3 .

(Step 2) Next, regarding the region overlapping with the R pixel (emission peak wavelength is about 620nm), fix the thicknesses of the high refractive index layers 16a, 16b, 16c and the low refractive index layers 17a, 17b, 17c to be obtained in step 1. The thicknesses of the pixel electrode 4R, the hole injection/transport layer 28R, the intermediate layer 29R, and the light emitting layer 7R are optimized. Specifically, the thicknesses of the high-refractive-index layers 16a, 16b, 16c and the low-refractive-index layers 17a, 17b, 17c are determined while changing the pixel electrode 4R, the hole injection/transport layer 28R, the intermediate layer 29R, and the light emitting layer. The thickness of the layer 7R is repeatedly estimated at the intensity of the emission peak wavelength of the total reflected light emitted from the insulator multilayer film 18 to the outside, and the thickness combination that emits the lowest intensity reflected light at the emission peak wavelength is selected as the optimum thickness combination. At this stage, the optical constants (refractive index and extinction coefficient) for the red wavelength (620 nm) are used. This achieves the same thickness of each layer with respect to the area overlapping the R pixel of FIG. 3 .

(Step 3) Next, regarding the region overlapping with the B pixel (emission peak wavelength is about 470nm), the thicknesses of the high refractive index layers 16a, 16b, 16c and the low refractive index layers 17a, 17b, 17c are fixed as determined in step 1. Based on the obtained values, the thicknesses of the pixel electrode 4R, the hole injection/transport layer 28R, the intermediate layer 29R, and the light emitting layer 7R are optimized. Specifically, the thicknesses of the high-refractive-index layers 16a, 16b, 16c and the low-refractive-index layers 17a, 17b, 17c are determined while changing the pixel electrode 4R, the hole injection/transport layer 28R, the intermediate layer 29R, and the light emitting layer. The thickness of the layer 7R is repeatedly estimated at the intensity of the emission peak wavelength of the total reflected light emitted from the insulator multilayer film 18 to the outside, and the thickness combination that emits the lowest intensity reflected light at the emission peak wavelength is selected as the optimum thickness combination. At this stage, the optical constants (refractive index and extinction coefficient) for the blue wavelength (470 nm) are used. This achieves the same thickness as that of each layer in the region overlapping with the B pixel in FIG. 3 .

As described above, first, the thicknesses of the high-refractive-index layers 16a, 16b, 16c and the low-refractive-index layers 17a, 17b, 17c including the insulator laminated film 18 are determined for the region overlapping with the G pixel, and then the thicknesses of the layers with other pixels are determined. The overlapping regions fix these layers of the insulator multilayer film 18 and determine the thickness of other layers. However, in the optimization step (step 1) of the high-refractive-index layers 16a, 16b, 16c and low-refractive-index layers 17a, 17b, 17c, the region overlapping any pixel of R, G, and B can be determined as the thickness. benchmark. However, if, as in the present embodiment, the area overlapping with the G pixel at almost the central wavelength of visible light is taken as a reference, it is easy to determine the pixel electrode 4R, the hole injection/transport layer 28R, the intermediate layer 29R, and the light emitting layer 7R. With regard to any of the regions overlapping with the R pixel, the G pixel, and the B pixel, high-intensity light is emitted outward.

10 to 12 are graphs showing reflectance spectra for light perpendicularly incident on the organic EL device 100 through the transparent substrate 1 from outside the region overlapping with each pixel of the organic EL device 100 of this embodiment. FIG. 10 shows the reflectance spectrum for the region overlapping the R pixel, FIG. 11 shows the reflectance spectrum for the region overlapping the G pixel, and FIG. 12 shows the reflectance spectrum for the region overlapping the B pixel. From these figures, it was confirmed that the reflectance of one wavelength within ±20 nm of the emission peak wavelengths of the R, G, and B pixels is lower than the reflectance of other wavelengths within ±50 nm of the emission peak wavelengths. For example, when light is vertically incident on the organic EL device 100 from the outside, within the range of the emission peak wavelength (620nm) ±50nm of the R pixel, the reflectance of a certain wavelength within ±20nm of the emission peak wavelength of the R pixel becomes the lowest. .

According to the method of determining the thickness of each layer in this example, the same organic EL device 100 as in Example 1 was obtained (details are shown in FIG. 3 ). Therefore, the graph showing the spectrum of the light emitted through the transparent substrate 1 from the region overlapping with each pixel of the organic EL device 100 obtained in this embodiment is the same as that in FIG. 5 . As described about Example 1, referring to FIG. 5 and FIG. 6 about Comparative Example, it becomes clear that according to this implementation flow, the color purity of output light can be improved.

In addition, the plurality of low-refractive index layers 17a, 17b, and 17c in the insulator laminated film 18 have different thicknesses from each other, but the low-refractive index layers 17a, 17b, and 17c are respectively separated from the R pixel, the G pixel, and the B pixel. There is the same thickness in any overlapping region, and the multiple high-refractive index layers 16a, 16b, 16c have the same thickness in the region overlapping with any one of the R pixel, G pixel, and B pixel respectively, so there is no It is necessary to change the thickness by pixel. That is, the insulator laminated film 18 overlapping the R pixel, the G pixel, and the B pixel has a common structure. In addition, it is not necessary to separately design layers suitable for the resonance of R light, the resonance of G light, and the resonance of B light. In addition, since the second interlayer insulating layers 16a to 16c and 17a to 17c have the same thickness, all the contact holes 24 can be collectively formed by etching. Therefore, the organic EL device 100 has a simple structure and is easy to manufacture.

Conventionally, in a structure in which light is resonated with an insulator laminated film in which a plurality of low-refractive-index layers and a plurality of high-refractive-index layers are alternately laminated, generally the low-refractive-index layers have the same thickness as each other, and the high-refractive index The frequency layers have the same thickness as each other, but the inventors have found that it is not necessarily possible to obtain a significant resonance effect with such a configuration. When the plurality of low-refractive-index layers 17a, 17b, and 17c have mutually different thicknesses and the plurality of high-refractive-index layers 16a, 16b, and 16c have mutually different thicknesses as in this embodiment, any optical resonance of R, G, and B , can be released with high intensity.

In addition, according to this embodiment, the combination of layers from the pixel electrode 4 (light-transmitting electrode) to the light-emitting layer 7 (including the pixel electrode 4 and the light-emitting layer 7) is different according to the light-emitting color of the pixel. Even if the insulator multilayer film 18 in which the pixels, G pixels, and B pixels are stacked has a common structure, it is easy to obtain appropriate reflection characteristics corresponding to the respective luminous colors. Although it is difficult or often complicated to form thin films of different thicknesses according to regions, when using a polymer-based light-emitting layer 7, inkjet can be used to form the hole injection/transport layer 28 and the light-emitting layer 7. As in the method of dropping the liquid material as in the conventional method, the thicknesses of the hole injection/transport layer 28 and the light emitting layer 7 can be easily controlled by appropriately adjusting the amount of the liquid material dropped.

<combination of other thicknesses>

If the thickness of each layer is calculated from the above-mentioned Example 1 and Example, not only the above-mentioned combinations of thicknesses ( FIG. 3 ) but also other combinations are taken. 13 to 15 show these combinations (Type A to Type L). In FIGS. 13 to 15 , R, G, and B denote regions overlapping with R pixels, regions overlapping with G pixels, and regions overlapping with B pixels, respectively. As in FIG. 3 , in these figures, the upper row corresponds to the layer farther from the first counter electrode.

In the organic EL devices of type A to type L shown in FIGS. 13 to 15 , if the light-emitting layer 7 emits light, it passes through the interface between the intermediate layer 29 and the hole injection/transport layer 28, the hole injection/transport layer 28 and the pixel electrode 4, the interface between the pixel electrode 4 and the insulator lamination film 18, and the low-refractive-index second interlayer insulating layers 17a to 17c and the high-refractive-index second interlayer insulating layer 16a Reflection at the interface between ~ 16c, resonant action occurs, at any luminous peak wavelength of R pixel, G pixel, B pixel, light with higher intensity than when there is no insulator laminated film 18 flows from the insulator laminated film 18 to the outside (For the insulator laminated film 18, the side opposite to the light emitting layer 7, that is, the transparent substrate 1 side) is emitted. In addition, in the same organic EL device 100, when light is vertically incident on the pixel electrode 4 (light-transmitting electrode) 4 and the light-emitting layer 7 from the side of the insulator laminated film 18, it passes through the intermediate layer 29 and the hole injection/transport layer. 28, the interface between the hole injection/transport layer 28 and the pixel electrode 4, the interface between the pixel electrode 4 and the insulator lamination film 18, and the second interlayer insulating layers 17a to 17c of low refractive index In the reflection of the interface between the second interlayer insulating layers 16a-16c with high refractive index, the reflectance of a wavelength located within ±20nm of each luminous peak wavelength of the R pixel, G pixel, and B pixel is greater than the luminous The reflectance of other wavelengths within ±50 nm of the peak wavelength is still low. Therefore, with regard to Embodiment 1 and Embodiment 2, the effects described above can be obtained.

In Example 1 and Example 2, the number of layers inside the insulator laminated film 18 , that is, the total number of layers of the high-refractive index layer and the low-refractive index layer was six. However, as type G in FIG. 14, the number of layers inside the insulator laminated film 18 may be 8 as illustrated, or other numbers such as 2, 4, 10 or more may be used. However, as the number of laminations increases, the viewing angle dependence tends to increase. That is, there is a tendency that the angle of view becomes narrow.

<Example 3>

The organic EL device 100 can be modified as shown in FIG. 16 . In Example 3 shown in FIG. 16, color filters CF are superimposed on R pixels, G pixels, and B pixels, respectively. The color filter CF transmits light in the wavelength range corresponding to the light emission color of the pixel, and absorbs light in other wavelength ranges. For example, the color filter CF overlapping the R pixel transmits light in the red wavelength region (around 620 nm) and absorbs light in other wavelength regions. The color filter CF is bonded to the transparent substrate 1 on the side where light is emitted from the pixels, and is surrounded by a black matrix matrix BM. The protective film 19 is overlaid on the color filter CF and the black matrix matrix BM, and the insulator laminated film 18 is provided thereon. By superimposing the color filter CF on each pixel in this way, contrast and color purity can be improved. That is, the color purity of light when a pixel is emitting light is improved, and when the pixel is not emitting light, the pixel appears darker.

<Example 4>

Fig. 17 shows an inorganic EL device according to Example 4 of the present invention. As the EL device of the present invention, an organic EL device will be described as an example, but an inorganic EL device is also within the scope of the present invention. As shown in FIG. 17, the inorganic EL device has a light-transmitting electrode 202 formed of ITO on a glass transparent substrate 201, a first insulating film 203 formed of _SiNx thereon, and a light-emitting layer formed thereon. 204, a second insulating film 205 formed of SiN _x thereon, and a back electrode 206 formed of Al thereon. According to the present invention, between the transparent substrate 201 and the light-transmitting electrode 202, there is an insulator laminated film 207 having a low refractive index layer made of _SiNx and a high refractive index layer 209 made of, for example, _SiNx . In any overlapping region of the pixels of G and B, the respective thicknesses of the low-refractive index layer 208 and the high-refractive index layer 209 are the same, and the transparent substrate 201, the first insulating film 203, the light-emitting layer The combination of the thickness of 204 is different.

Moreover, the thickness of each layer was determined similarly to Example 1 or Example 2. In the obtained inorganic EL device, if the light-emitting layer 204 emits light, the interface between the first insulating film 203 and the translucent electrode 202, the interface between the translucent electrode 202 and the insulator laminated film 207, and the low refractive index The reflection at the interface between the layer 208 and the high-refractive index layer 209 produces a resonance effect, and at any luminous peak wavelength of the R pixel, the G pixel, or the B pixel, light with a higher intensity than that without the insulator laminated film 207 is emitted from the The insulator laminated film 207 is emitted to the outside (the insulator laminated film 207 is on the side opposite to the light emitting layer 204 , that is, the transparent substrate 201 side). In addition, in the same inorganic EL device, when light is vertically incident on the light-transmitting electrode 202 and the light-emitting layer 204 from the side of the insulator laminated film 207, due to the interface between the first insulating film 203 and the light-transmitting electrode 202, the transmission The reflection of the interface between the photoelectrode 202 and the insulator lamination film 207, and the interface between the low refractive index layer 208 and the high refractive index layer 209 is located at the respective luminescence peak wavelengths of the R pixel, the G pixel, and the B pixel ± The reflectance of one wavelength within 20 nm is lower than the reflectance of other wavelengths within ±50 nm of the emission peak wavelength. Therefore, with regard to Embodiment 1 and Embodiment 2, the effects described above are obtained. The first insulating film 203 may not be present.

<electronic equipment>

Next, various electronic appliances having the EL device of the present invention will be described with reference to FIG. 18. FIG. Fig. 18(a) is a perspective view showing an example of a mobile phone. In FIG. 18( a ), reference numeral 600 denotes a mobile phone main body, and reference numeral 601 denotes a display portion using the arbitrary EL device. Fig. 18(b) is a perspective view showing an example of a portable information processing device such as a word processor or a personal computer. In FIG. 18( b ), reference numeral 700 denotes an information processing device, reference numeral 701 denotes an input unit such as a keyboard, reference numeral 703 denotes a main body of an information processing device, and reference numeral 702 denotes a display unit using any of the above-mentioned EL devices. In FIG. 18(c), reference numeral 800 denotes a wristwatch main body, and reference numeral 801 denotes a display portion using any of the EL devices described above.

Each electronic device shown in FIGS. 18( a ) to ( c ) has any of the above-mentioned EL devices as a display unit, and can achieve high color purity.

Claims (6)

1. EL device has:

R pixel, this R pixel have the 1st electrode, the opposite electrode relative with described the 1st electrode and are clipped between described the 1st electrode and the described opposite electrode and send the 1st luminescent layer of the light with the 1st peak wavelength;

B pixel, this B pixel have the 3rd electrode, the described opposite electrode relative with described the 3rd electrode and are clipped between described the 3rd electrode and the described opposite electrode and send the 2nd luminescent layer of the light with 2nd peak wavelength different with described the 1st peak wavelength;

G pixel, this G pixel have the 5th electrode, the described opposite electrode relative with described the 5th electrode and are clipped between described the 5th electrode and the described opposite electrode and send the 3rd luminescent layer of the light with 3rd peak wavelength different with described the 1st, 2 peak wavelengths;

The stacked film of insulator, the stacked film of this insulator be formed on described the 1st electrode and the face described the 1st luminescent layer opposition side, on described the 3rd electrode and the face described the 2nd luminescent layer opposition side and on described the 5th electrode and the face described the 3rd luminescent layer opposition side,

Described the 1st, 3,5 electrodes are optically transparent electrodes;

The stacked film of described insulator has comprised a plurality of low-index layers with regulation refractive index and has had a plurality of high refractive index layers than the refractive index of described low-refraction floor height; Described low-index layer and described high refractive index layer are alternately laminated;

Each of described a plurality of low-index layers, the light-emitting zone whole district of striding described R pixel, described G pixel and described B pixel forms, though with described R pixel, described G pixel and described B pixel in any one overlapping areas in also have the same thickness;

Each of described a plurality of high refractive index layers, the light-emitting zone whole district of striding described R pixel, described G pixel and described B pixel forms, though with described R pixel, described G pixel and described B pixel in any one overlapping areas in also have the same thickness;

A plurality of described low-index layers have different thickness each other;

A plurality of described high refractive index layers have different thickness each other,

When light from stacked film one side direction the described the 1st of described insulator, the 3rd, the 5th electrode and the described the 1st, the 3rd, during the 5th luminescent layer vertical incidence, by being in intermediate layer between stacked film of described insulator and the described opposite electrode and the interface between the injection/transfer layer of hole, described hole injection/transfer layer and the described the 1st, the 3rd, interface between the 5th electrode, the described the 1st, the 3rd, the reflection at the interface between the interface between the 5th electrode and the stacked film of described insulator and described a plurality of low-index layer and the described a plurality of high refractive index layer, make and be positioned at described R pixel, described G pixel, the reflectivity of the wavelength in each peak luminous wavelength ± 20nm of described B pixel is lower than the reflectivity of other wavelength in this peak luminous wavelength ± 50nm.

2. EL device according to claim 1, it is characterized in that: the thickness that determines described a plurality of low-index layer and described a plurality of high refractive index layers, with convenient light during from stacked described optically transparent electrode of film one side direction of described insulator and described luminescent layer incident, at least pass through the reflection at the interface between described optically transparent electrode and the stacked film of described insulator, and the reflection at low-index layer adjacent one another are in described a plurality of low-index layer and the described a plurality of high refractive index layer and the interface between the high refractive index layer, make described R pixel, described G pixel and described B pixel each peak luminous wavelength ± reflectivity of wavelength in the 20nm, be lower than each peak luminous wavelength ± except the wavelength in the 20nm each peak luminous wavelength ± reflectivity in the 50nm.

3. EL device according to claim 1 and 2 is characterized in that:

Described optically transparent electrode and comprise the combination of the layer thickness from described optically transparent electrode to described luminescent layer of described luminescent layer is according to the glow color of described pixel and difference.

4. EL device according to claim 1 is characterized in that:

Described EL device is an organic El device;

Between described luminescent layer and described optically transparent electrode, dispose the intermediate layer, so that minimizing hole or electronics spill to described optically transparent electrode from described luminescent layer.

5. EL device according to claim 1 is characterized in that:

Light at the stacked film of described insulator penetrates side configuration colour filter.

6. an e-machine is characterized in that: have the described EL device of claim 1.

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