JP2007134153A - Electroluminescent device, and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electroluminescent device capable of improving light extraction efficiency, and improving the extraction efficiency and viewing angle of blue light relatively, and provide electronic equipment to which the electroluminescent device is mounted. <P>SOLUTION: In the organic EL device 1, an element substrate including a pixel electrode 16, an organic light emitting layer 20, a cathode 24, a thin film sealing layer 26, and a color filter substrate including color filters 34R, 34G and 34B are pasted together via an adhesive 28. The color filters 34R, 34G and 34B are set with mutually different refractive indexes so that the total reflection of the blue light may be the least at a boundary face 37. Moreover, since a boundary face 38 shows an uneven shape, the total reflection of light is hard to be generated at the boundary face 38, and the blue light is scattered most, thus contributing to an improvement of the viewing angle of blue. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to an electroluminescence device using an electroluminescence phenomenon,
The present invention also relates to an electronic device equipped with the electroluminescence device.

An electroluminescence (hereinafter also abbreviated as “EL”) device is used as a display device in various electronic devices because of its thinness, light weight, wide viewing angle, and high-speed response. FIG. 9 shows a cross-sectional view in the display region of an organic EL device which is an example of such an EL device.
This organic EL device includes a reflective film 12, an insulating layer 14, and a pixel electrode 16 as an anode on a substrate 10.
, Hole transport layer 18, organic light emitting layer 20, electron transport layer 22, cathode 24, and thin film sealing layer 26 are stacked in this order, and glass substrate 30 corresponds to red, green, and blue, respectively. A color filter substrate on which color filters 35R, 35G, and 35B (hereinafter collectively referred to as “color filter 35”) are laminated is bonded through an adhesive 28. This organic EL device includes an organic light emitting layer 20 disposed between the pixel electrode 16 and the cathode 24.
The light emitting device emits light from the organic light emitting layer 20 by passing a current through the color filter substrate, and extracts the light from the color filter substrate side. The extracted light has a color of red, green, or blue due to interference by the optical resonator formed by the reflective film 12 and the cathode 24 and the effect of the color filter 35.

Here, the refractive index of the organic light emitting layer 20 is generally higher than the refractive index of the glass substrate 30. For this reason, before the light emitted from the organic light emitting layer 20 is transmitted through the glass substrate 30, an interface between a layer having a certain refractive index and a layer having a relatively smaller refractive index is always present in this direction. It will be transparent. At this time, since a part of the light is reflected by the total reflection phenomenon at the interface, there is a problem that the light from the organic light emitting layer 20 cannot be efficiently extracted outside the organic EL device.

With respect to this problem, Patent Document 1 discloses a technique for reducing total reflection by forming irregularities on the surface of the glass substrate 30 on the organic light emitting layer 20 side.

JP 2001-76864 A

However, the organic EL device has a problem in that it is relatively difficult to obtain blue light extraction efficiency as compared with red and green, and the configuration described in Patent Document 1 still does not solve this problem. In particular, when the optical resonator is used, there is a problem that it is relatively difficult to obtain a blue viewing angle characteristic.

In view of the above problems, an object of the present invention is to improve the light extraction efficiency by reducing total reflection at the light interface from the light emitting layer, and relatively improve the blue light extraction efficiency and viewing angle. It is an object of the present invention to provide an electroluminescence device that can be made to operate, and an electronic device equipped with the electroluminescence device.

In order to solve the above problems, an electroluminescence device of the present invention is an electroluminescence device having a plurality of light emitting regions, each of which corresponds to one of a plurality of different colors. A plurality of first electrodes arranged corresponding to the light emitting region, a second electrode having translucency arranged opposite to the first electrode, the first electrode and the second electrode, A light emitting layer disposed between the first functional layer, the first functional layer disposed on the opposite side of the second electrode from the side on which the light emitting layer is disposed, and the first functional layer on the first functional layer. A second functional layer disposed in contact with the layer, and an interface between the first functional layer and the second functional layer has an uneven shape for scattering light emitted from the light emitting layer, One functional layer includes the light emitting region corresponding to one of the plurality of different colors. The refractive index, and the refractive index in the light emitting region corresponding to the other color and being different from the.

In the above configuration, the light from the light emitting layer enters the first functional layer, and then passes through the interface with the second functional layer and enters the second functional layer. Since the interface has a concavo-convex shape, even if the refractive index of the second functional layer is smaller than the refractive index of the first functional layer, the total reflection phenomenon at the interface is unlikely to occur, and light is efficiently transferred to the second functional layer. Can be transmitted.

Further, transmitted light is scattered at the uneven interface. The degree of this scattering is
It depends on the difference in refractive index between the functional layer and the second functional layer. More specifically, scattering increases as the refractive index of the second functional layer is smaller than the refractive index of the first functional layer. The greater the scattering, the wider the viewing angle for the color belonging to the light emitting area where the light is emitted. Here, in the above configuration, since the refractive index of the first functional layer is made different according to the color of the light emitting region, the refractive index is set so as to generate an appropriate refractive index difference in the light emitting region of a desired color. By setting, the viewing angle for the color can be expanded.

Furthermore, the amount of light that is incident on the first functional layer from the opposite side of the second functional layer differs depending on the color of the light emitting region. This is because the refractive index of the first functional layer varies depending on the color of the light emitting region. Therefore, the light extraction efficiency for the desired color can be improved by setting the refractive index of the first functional layer in the light emitting region of the desired color relatively large with respect to the other colors.

As described above, according to the electroluminescence device having the above-described configuration, it is possible to reduce the total reflection of light from the light emitting layer at the interface between the first functional layer and the second functional layer, thereby improving the light extraction efficiency. At the same time, the viewing angle for light of a desired color can be improved relative to other colors. Furthermore, it is possible to selectively improve the light extraction efficiency of a desired color.

In the electroluminescence device, the refractive index of the first functional layer is preferably larger than the refractive index of the second functional layer in any of the light emitting regions. According to such a configuration, an interface having a concavo-convex shape is formed between a layer having a high refractive index (ie, the first functional layer) and a layer having a relatively low refractive index (ie, the second functional layer). Therefore, total reflection when light passes from the former to the latter can be reduced. Therefore, light from the light emitting layer can be extracted more efficiently in the light emitting region corresponding to any color. If the refractive index is set as described above, the scattering of light from the light emitting layer at the interface between the first functional layer and the second functional layer can be increased. Therefore, the viewing angle of the electroluminescence device can be widened.

In the electroluminescence device, the difference between the refractive index of the first functional layer and the refractive index of the second functional layer is preferably 0.03 or more and 1.00 or less in any of the light emitting regions. When the difference between the refractive index of the first functional layer and the refractive index of the second functional layer is smaller than 0.03,
Total reflection outside the interface between the first functional layer and the second functional layer may increase, and a desired light extraction efficiency may not be obtained. In addition, the degree of scattering at the interface between the first functional layer and the second functional layer is reduced, and the viewing angle may be narrowed. On the other hand, if the difference between the refractive index of the first functional layer and the refractive index of the second functional layer is larger than 1.00, total reflection at the interface increases, and a desired light extraction efficiency may not be obtained. Therefore, according to the configuration in which the difference between the refractive index of the first functional layer and the refractive index of the second functional layer is 0.03 or more and 1.00 or less as described above, the electroluminescence device can be more reliably provided. The light extraction efficiency can be increased.

Another electroluminescent device of the present invention is an electroluminescent device having a plurality of light emitting regions, each corresponding to one of a plurality of different colors, on a substrate and on the substrate, in contact with the substrate. A first functional layer disposed on the first functional layer, a plurality of translucent first electrodes disposed on the first functional layer corresponding to the light emitting region, and disposed opposite to the first electrode. A second electrode, and a light emitting layer disposed between the first electrode and the second electrode,
The interface between the first functional layer and the substrate has an uneven shape that scatters light emitted from the light emitting layer, and the first functional layer corresponds to one of the plurality of different colors. The refractive index in the light emitting region is different from the refractive index in the light emitting region corresponding to another color.

In the above configuration, light from the light emitting layer enters the first functional layer, and then passes through the interface with the substrate and enters the substrate. Since the interface has a concavo-convex shape, even if the refractive index of the substrate is smaller than the refractive index of the first functional layer, the total reflection phenomenon hardly occurs at the interface, and light can be efficiently transmitted to the substrate. .

Further, transmitted light is scattered at the uneven interface. The degree of this scattering is
Depends on the refractive index difference between the functional layer and the substrate. More specifically, the scattering increases as the refractive index of the substrate is smaller than the refractive index of the first functional layer. The greater the scattering, the wider the viewing angle for the color belonging to the light emitting area where the light is emitted. Here, in the above configuration, since the refractive index of the first functional layer is made different according to the color of the light emitting region, the refractive index is set so as to generate an appropriate refractive index difference in the light emitting region of a desired color. By setting, the viewing angle for the color can be expanded.

Furthermore, the light incident on the first functional layer from the opposite side of the substrate differs in the amount of light that is totally reflected upon the incidence depending on the color of the light emitting region. This is because the refractive index of the first functional layer varies depending on the color of the light emitting region. Therefore, the light extraction efficiency for the desired color can be improved by setting the refractive index of the first functional layer in the light emitting region of the desired color relatively large with respect to the other colors.

As described above, according to the electroluminescence device having the above-described configuration, it is possible to reduce the total reflection of light from the light emitting layer at the interface between the first functional layer and the substrate, thereby improving the light extraction efficiency and It is possible to improve the viewing angle for light of a certain color relative to other colors. Furthermore, it is possible to selectively improve the light extraction efficiency of a desired color.

In the electroluminescence device, the refractive index of the first functional layer is preferably larger than the refractive index of the substrate in any of the light emitting regions. According to such a configuration, the concavo-convex shape interface is provided between the layer having a high refractive index (ie, the first functional layer) and the layer having a relatively low refractive index (ie, the substrate). The total reflection when light is transmitted from the former to the latter can be reduced. Therefore, light from the light emitting layer can be extracted more efficiently in the light emitting region corresponding to any color. If the refractive index is set as described above, the scattering of light from the light emitting layer at the interface between the first functional layer and the substrate can be increased. Therefore, the viewing angle of the electroluminescence device can be widened.

In the electroluminescence device, the difference between the refractive index of the first functional layer and the refractive index of the substrate is preferably 0.03 or more and 1.00 or less in any of the light emitting regions. If the difference between the refractive index of the first functional layer and the refractive index of the substrate is smaller than 0.03, total reflection increases at other than the interface between the first functional layer and the substrate, and the desired light extraction efficiency cannot be obtained. There is. In addition, the degree of scattering at the interface between the first functional layer and the substrate may be reduced, resulting in a narrow viewing angle. On the other hand, if the difference between the refractive index of the first functional layer and the refractive index of the substrate is larger than 1.00, total reflection at the interface increases, and a desired light extraction efficiency may not be obtained.
Therefore, the difference between the refractive index of the first functional layer and the refractive index of the substrate as described above is 0.03 or more and 1.0.
According to the configuration of 0 or less, the light extraction efficiency of the electroluminescence device can be more reliably increased.

In the electroluminescence device, the first functional layer further includes a third functional layer disposed in contact with a surface opposite to the interface having the concavo-convex shape, and the refractive index of the first functional layer is The ratio of the third functional layer to the refractive index is preferably greater than 0.83 and not greater than 1.50 in any of the light emitting regions. According to the above configuration, the third functional layer to the first
Total reflection when light enters the functional layer can be reduced or eliminated. If the ratio of the refractive index of the first functional layer to the refractive index of the third functional layer is larger than 0.83, the influence of the total reflection is canceled by the effect of improving the light extraction efficiency by other components, and the electroluminescence device The light extraction efficiency as a whole can be substantially improved. Also,
If the ratio exceeds 1.00, total reflection does not occur. However, if the ratio exceeds 1.50, the refractive index of the first functional layer increases, so total reflection when light enters the second functional layer or the substrate from the first functional layer cannot be ignored and is high. The light extraction efficiency may not be obtained. Therefore, if the ratio is greater than 0.83 and not greater than 1.50, the light extraction efficiency of the electroluminescent device can be more reliably increased.

In the electroluminescence device, the light emitting region includes a red light emitting region from which red light emission can be obtained, a green light emitting region from which green light emission can be obtained, and a blue light emitting region from which blue light emission can be obtained, and the first functional layer includes The refractive index in the blue light emitting region is preferably different from the refractive index in the red light emitting region and the refractive index in the green light emitting region. The electroluminescence device having the above-described configuration can perform color light emission based on red, green, and blue light emission. In addition, by making the refractive index of the first functional layer in the blue light emitting region different from the refractive index in other regions, the light extraction efficiency and the viewing angle for blue light emission, for which it is difficult to obtain the light emission efficiency, can be reduced with respect to other colors. It can be improved relatively. As a result,
Color light emission with good white balance can be performed without adjusting the drive current amount of each color. Further, based on this, the life of the electroluminescence device can be extended.

In the electroluminescence device, the first functional layer includes the blue light emitting region,
It is preferable that the red light emitting region and the green light emitting region have different refractive indexes. According to such a configuration, it is possible to adjust the light extraction efficiency and the viewing angle for all colors of red, green, and blue, and color light emission with better white balance can be performed.

In the electroluminescence device, it is preferable that the first functional layer has a refractive index in the blue light emitting region that is larger than a refractive index in the red light emitting region and a refractive index in the green light emitting region. According to such a configuration, it is possible to improve the viewing angle of the blue light emission by scattering the blue light emission, which is difficult to obtain the viewing angle characteristics, at the largest interface at the uneven surface. In addition, with respect to blue light emission, total reflection at the interface of the first functional layer on the side opposite to the uneven shape can be suppressed to be relatively small with respect to other colors. This is because, in the blue light emitting region, the refractive indexes of the two layers related to the total reflection are
This is because it is set in a direction in which total reflection hardly occurs relative to other colors.

An electronic apparatus according to the present invention includes the above-described electroluminescence device. Such an electronic device can perform color light emission or color display with good white balance in a light emitting unit or a display unit in which the electroluminescence device is incorporated. Moreover, it has high reliability based on the long lifetime of the electroluminescent device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings shown below, the dimensions and ratios of the components are appropriately different from the actual ones in order to make the components large enough to be recognized on the drawings.

(First embodiment)
<A. Configuration of organic EL device>
FIG. 1 is a block diagram schematically showing a configuration of an organic EL device 1 as an “electroluminescence device” of the present invention. The organic EL device 1 includes a data line driving circuit 60, a scanning line driving circuit 61, and a plurality of organic EL elements 70. A plurality of data lines 91 are connected to the data line driving circuit 60, and a plurality of scanning lines 92 are connected to the scanning line driving circuit 61, respectively.

The organic EL elements 70 are arranged in a matrix corresponding to the intersections of the data lines 91 and the scanning lines 92, and constitute a display area 90 as a whole. Each of the organic EL elements 70 is
Light is emitted in accordance with a drive signal applied from the data line driving circuit 60 and the scanning line driving circuit 61 via the data line 91 and the scanning line 92. Each of the organic EL elements 70 emits red light, green light, or blue light. The organic EL device 1 is a device that performs color display by a set of light emission of the organic EL elements 70 in the display region 90.

FIG. 2 is a cross-sectional view of the organic EL device 1 at a portion including three adjacent organic EL elements 70. As shown in this figure, the organic EL device 1 includes a reflective film 12 and an insulating layer 14 on a substrate 10.
A pixel substrate 16 as an anode, a hole transport layer 18, an organic light emitting layer 20, an electron transport layer 22, a cathode 24, and a thin film sealing layer 26 are laminated in this order, and a red color on a glass substrate 30. A color filter substrate formed by laminating color filters 34R, 34G, and 34B (hereinafter collectively referred to as “color filters 34”) corresponding to green and blue, respectively, is used as an adhesive 2.
8 are bonded together. The display area 90 of the organic EL device 1 includes a set of light emitting areas 40 that are smaller light emitting units. The light emitting area 40 includes a red light emitting area 40R that emits red light, a green light emitting area 40G that emits green light, and a blue light emitting area 40B that emits blue light.
Is included. An element composed of components from the reflective film 12 to the cathode 24 corresponds to the organic EL element 70 described above, and one organic EL element 70 is formed in one light emitting region 40. Here, the pixel electrode 16 is a “first electrode” in the present invention, and the cathode 24 is a “second electrode”.
The organic light emitting layer 20 is the “light emitting layer”, the color filter 34 is the “first functional layer”, and the glass substrate 3
0 corresponds to the “second functional layer”, and the adhesive 28 corresponds to the “third functional layer”.

The substrate 10 is a so-called TFT element substrate in which a TFT (Thin Film Transistor) element or the like is formed on a glass substrate. The TFT element, the data line 91, the scanning line 92, and the like using a known technique on the glass substrate. Various electrodes, insulating layers and the like are formed. The reflective film 12 is
Made of aluminum or silver. The pixel electrode 16 is a transparent electrode made of ITO (Indium Tin Oxide) disposed on the reflective film 12 with an insulating layer 14 for preventing a short circuit with the reflective film 12 interposed therebetween. One pixel electrode 16 is disposed in each light emitting region 40, and each pixel electrode 16 is connected to the data line 91 through a TFT element included in the substrate 10. The cathode 24 is formed by forming an alloy of magnesium and silver in a half mirror state.

Between the pixel electrode 16 and the cathode 24, a hole transport layer 18, an organic light emitting layer 20, an electron transport layer 2 are provided.
2 are stacked in this order. The organic light emitting layer 20 is a layer of an organic light emitting material that exhibits an electroluminescence phenomenon. By applying a voltage between the pixel electrode 16 and the cathode 24, holes are injected from the hole transport layer 18 into the organic light emitting layer 20 and electrons are injected from the electron transport layer 22. Emits light when they recombine. Organic light emitting layer 20
A part of the light from the light directly passes through the cathode 24, and part of the light is reflected by the reflective film 12 and then passes through the cathode 24. In any case, light from the organic light emitting layer 20 passes through the cathode 24 and then passes through the thin film sealing layer 26, the adhesive 28, the color filter 34, and the glass substrate 30 in order.
The organic EL device 1 causes the organic light emitting layer 20 to flow by passing a current through the organic light emitting layer 20 in this way.
Is a front emission type organic EL device that emits light from the color filter substrate side.

Here, the reflective film 12 and the cathode 24 constitute a so-called optical resonator. For this reason,
The light emitted from the organic light emitting layer 20 reciprocates between the reflective film 12 and the cathode 24, and only the light having the resonance wavelength is amplified and extracted from the color filter substrate side. Accordingly, light having a spectrum with a high peak intensity and a narrow width can be extracted, and the color reproducibility of light emitted by the organic EL device 1 can be improved.

The resonance wavelength can be adjusted by changing the length of the optical resonator. In the organic EL device 1, the length of the optical resonator is adjusted by changing the thickness of the pixel electrode 16. More specifically, the length of the optical resonator and the resonance wavelength are increased in this order by forming the pixel electrodes 16 thick in this order in each of the blue light emitting region 40B, the green light emitting region 40G, and the red light emitting region 40R. It has become. The resonance wavelength is set to a wavelength corresponding to blue in the blue light emitting region 40B, green in the green light emitting region 40G, and red in the red light emitting region 40R. As a result, blue, green, or red light is selectively emitted from the cathode 24.

The thin-film sealing layer 26 formed so as to cover the cathode 24 is a light-transmitting member made of SiON, protects the organic EL element 70, and is formed for forming an optical resonator.
It plays the role of smoothing the gap between the surfaces.

The color filter 34 is a resin that colors transmitted light by absorbing a specific wavelength component of incident light. By arranging the color filter 34, the color purity of the light extracted from the organic EL device 1 can be improved, the change in color due to the viewing angle can be suppressed, and the reflection of external light can be blocked to some extent. Here, the color filter 34 has a different refractive index in each color, the refractive index in the red color filter 34R is 1.65, the refractive index in the green color filter 34G is 1.70, and in the blue color filter 34B. The refractive index is 1.85.

The surface of the glass substrate 30 on which the color filter 34 is formed is preliminarily frosted with hydrofluoric acid or the like to form irregularities having a height of about 0.01 to 0.5 μm. Therefore, the interface 38 between the color filter 34 and the glass substrate 30 has an uneven shape. The refractive index of the glass substrate 30 is 1.50. The refractive index of the adhesive 28 for fixing the color filter substrate and the element substrate is 1.80.

<B. Behavior of light in organic EL devices>
Next, the behavior of light inside the organic EL device 1 having the above configuration will be described. The light emitted from the organic light emitting layer 20 is not totally reflected or scattered until reaching the adhesive 28. This is because there is no interface where light enters a layer having a relatively low refractive index in this section, and the interfaces of the layers are smooth. On the other hand, adhesive 28
In the optical path from to the glass substrate 30, total reflection or scattering may occur. This point will be described in detail below.

First, the behavior of light at the interface 37 between the adhesive 28 and the color filter 34 will be described. Since the refractive indexes of the red color filter 34R and the green color filter 34G are lower than the refractive index of the adhesive 28, part of the light incident on the color filters 34R and 34G from the adhesive 28 is totally reflected. Since the ratio of the refractive index of the color filter 34R to the refractive index of the adhesive 28 is about 0.91, light up to a total reflection angle of 66.44 ° can be transmitted to the color filter 34R side at this interface. As a rough estimate, about 73% of light is extracted to the color filter 34R side. Similarly, since the ratio of the refractive index of the color filter 34G to the refractive index of the adhesive 28 is about 0.94, light up to a total reflection angle of 70.81 ° can be transmitted to the color filter 34G side at this interface. is there. Approximately 78% of the light is extracted to the color filter 34G side. On the other hand, since the refractive index of the blue color filter 34B is higher than the refractive index of the adhesive 28, total reflection does not occur at this interface, and almost all light can be extracted to the color filter 34B side.

In this way, by adopting a configuration in which the refractive index of the color filter 34 is different for each light emitting region 40, blue light is extracted most efficiently at the interface 37 between the adhesive 28 and the color filter 34, and then green, The extraction efficiency decreases in the order of red.

Next, the behavior of light at the interface 38 between the color filter 34 and the glass substrate 30 will be described. Since the refractive index of the glass substrate 30 is lower than the refractive index of the color filter 34 of any color, generally total reflection occurs at these interfaces 38. However, as described above, the interface 38 has an uneven shape. Therefore, total reflection is less likely to occur. Therefore, light is efficiently extracted from the color filter 34 to the glass substrate 30.

Further, the transmitted light is scattered by the uneven shape at the interface 38, and the degree of the scattering is as follows.
The larger the difference in refractive index between the color filter 34 and the glass substrate 30, the larger it becomes. Now, this refractive index difference is the largest in the blue light emitting region 40B, and then decreases in the order of the green light emitting region 40G and the red light emitting region 40R. Therefore, blue light is scattered most greatly at the interface 38.

<C. Advantages of the invention>
Due to the behavior of light as described above, the organic EL device 1 mainly has two characteristics as described below.

First, as shown in Table 1, the blue light emission efficiency is high, and due to this, a good white balance can be realized. This is because the light extraction efficiency is selectively increased for blue light as described above. Moreover, based on the said characteristic, it has the characteristic that a lifetime can be lengthened.

The upper row in Table 1 shows the characteristics of the organic EL device having the conventional structure shown in FIG. 9, and the middle row has an uneven surface 38 as in the present embodiment and the color filter 34R from the conventional configuration.
, 34G, and 34B have different characteristics as described above. At this time, it can be seen that the blue light emission efficiency is improved about 1.5 times from 1.5 Cd / m ² to 5.8 Cd / m ² . Although not shown in the table, the green luminous efficiency is 2.5 Cd / m ² to 4
. Improved to approximately 1.8 times to 5 cd / m ^2, also 7.7C luminous efficiency of red from 5.0 cd / m ²
It is improved about 1.5 times to d / m ² .

Thus, since the blue light emission efficiency is greatly improved in the middle configuration of Table 1, the optical path length or interference condition of the optical resonator is changed while maintaining the blue light emission luminance at a certain level. Fine adjustment to increase the blue color purity. The organic EL device 1 according to the present embodiment that has been subjected to such fine adjustment from the middle configuration of Table 1 is shown in the lower data of Table 1. From these data, it can be seen that although the blue luminous efficiency is slightly reduced to 4.8 Cd / m ² , the blue color coordinates and color reproducibility are improved. Further, when the organic EL element 70 in each light emitting region 40 is driven with an equal current, white color coordinates are also (0.34, 0.37).
) And closer to the white spot, the white balance is improved.

By improving the white balance in this way, the life of the apparatus can be extended. That is, in the conventional configuration, one or two colors of organic E are used for white balance.
There is a problem that it is necessary to drive the L element 70 with a large current and the lifetime of only the organic EL element 70 is exhausted in a short time. However, the organic EL device 1 of the present embodiment has a substantially equal driving current. Since white balance can be achieved, the life can be extended accordingly. According to the inventor's experiment, the lifetime of the organic EL device 1 is improved by about 2.3 times that of the organic EL device having the conventional configuration.

The second feature of the organic EL device 1 is that it has a wide viewing angle characteristic as shown in Table 2. This is because, as described above, the degree of scattering is selectively increased for blue light.

In the upper part of Table 2, in the organic EL device having a conventional configuration, the chromaticity coordinate in the front is (0.3
3 and 0.33), when white display is performed by adjusting the drive current so that the white display is seen from the 45 ° viewing angle, and between the front and the 45 ° viewing angle. This shows the color difference. On the other hand, the lower row shows similar data for the organic EL device 1 of the present embodiment. As is apparent from this table, the organic EL device 1 has a very small color difference as compared with the conventional configuration, and the viewing angle characteristics are greatly improved. The reason is as follows.

In an organic EL device using an optical resonator, the wavelength of light emitted in a direction inclined from the front tends to shift to the short wavelength side with respect to the wavelength of light emitted in the front direction. For this reason, in an organic EL device having a conventional configuration, when viewed from an oblique direction, the luminance of blue in particular tends to decrease and the viewing angle of blue light tends to narrow. On the other hand, the organic EL device 1 of the present embodiment can avoid such problems because the blue viewing angle characteristics are improved because blue light is scattered the most, as described above, and the entire device can be avoided. The viewing angle characteristics are also improved.

<D. Preferred values of refractive index>
Next, in order to obtain the above effects, the relationship between the refractive indexes of the glass substrate 30, the color filter 34, and the adhesive 28 is preferably examined. The inventor of the present invention performed a simulation as to how many times the light extraction efficiency in the configuration (see Table 4) corresponding to the present embodiment is greater than the light extraction efficiency in the conventional configuration (see Table 3). That is, for each of the configurations shown in Tables 3 and 4, when light was incident from the adhesive side, what percentage of light was emitted from the glass substrate side was calculated, and the ratio was calculated. Here, the numerical values in Table 3 and Table 4 represent the refractive index of each component at 550 nm. In the following, the refractive indexes of the glass substrate, the color filter, and the adhesive in Table 4 are n (A) and n (
B) and n (C). In the simulation, n (A) was fixed at 1.50, n (C) was fixed at 1.80, and n (B) was changed from 1.38 to 2.30. In addition, the interface between each component is assumed to be smooth. However, only the interface between the glass substrate and the color filter in Table 4 has an uneven shape. The light extraction efficiencies in the conventional configuration A and the conventional configuration B shown in Table 3 are the same.

The simulation results are shown in Table 5. Table 5 shows n (B) -n when n (B) is changed.
The values of (A) and n (B) / n (C) and the ratio of the light extraction efficiency of the configuration of Table 4 to the light extraction efficiency of the configuration of Table 3 are shown.

As can be seen from Table 5, in the region where n (B) -n (A) is 0.03 or more, the light extraction efficiency is 1.1 times or more that of the conventional configuration. And as n (B) -n (A) increases, higher light extraction efficiency is obtained. However, although not shown in Table 5, n (B
When -n (A) exceeds 1.00, total reflection at the interface between the glass substrate and the color filter increases, and the desired light extraction efficiency may not be obtained.

In the region where n (B) / n (C) is greater than 0.83, the light extraction efficiency is improved as compared with the conventional configuration. And as n (B) / n (C) increases, higher light extraction efficiency is obtained. However, although not shown in Table 5, when n (B) / n (C) exceeds 1.50, n (B) itself increases, so that light enters the glass substrate from the color filter. The total reflection at the time cannot be ignored, and high light extraction efficiency may not be obtained.

Further, it can be seen that particularly high light extraction efficiency can be obtained in a region where n (B) / n (C) exceeds 1.00. This is considered to be caused by the fact that the refractive index of the color filter is higher than the refractive index of the adhesive and total reflection at the boundary is eliminated.

From the above, the difference between the refractive index of the glass substrate 30 and the refractive index of the color filter 34 is preferably 0.03 or more and 1.00 or less. Further, the adhesive 28 of the refractive index of the color filter 34 is used.
Is greater than 0.83 and not greater than 1.50, particularly not less than 1.00 and not greater than 1.50.
The following is preferable.

(Second Embodiment)
Subsequently, an organic EL device 1A according to a second embodiment of the present invention will be described with reference to a cross-sectional view of FIG. The configuration of the organic EL device 1A is the same as that of the first embodiment for the element substrate.
It is the same as that of the L device 1, and only the configuration of the color filter substrate is different. For this reason, below, it demonstrates centering on difference with the organic EL apparatus 1. FIG.

The color filter substrate of the organic EL device 1 </ b> A has a configuration in which a resin layer 32 and a color filter 35 are laminated in this order on a surface of the glass substrate 30 that has an uneven shape. The resin layer 32 includes a resin layer 32R in the red light emitting region 40R, a resin layer 32G in the green light emitting region 40G, and a resin layer 32B in the blue light emitting region 40B. Also, the resin layers 32R, 3
The refractive indexes of 2G and 32B are 1.60, 1.70, and 1.85, which are different from each other. The color filter 35 includes a color filter 35R in the red light emitting area 40R, and a green light emitting area 40.
The color filter 35G in G and the color filter 35B in the blue light emitting region 40B are different from the color filter 34 in the first embodiment, and their refractive indexes are all equal to 1.77. In the present embodiment, the resin layer 32 is the “first functional layer” of the present invention, the glass substrate 30 is the “second functional layer”, and the color filter 35 is the “third functional layer”.
Each corresponds.

In the organic EL device 1A having such a configuration, the behavior of light at the interface 37 between the color filter 35 and the resin layer 32 is as follows. That is, the resin layer 32R and the resin layer 3
Since the refractive index of 2G is lower than the refractive index of the color filter 35, a part of the light incident on the resin layers 32R and 32G from the color filter 35 is totally reflected. The ratio of the refractive index of the resin layer 32R to the refractive index of the color filter 35 is about 0.91, and the ratio of the refractive index of the resin layer 32G to the refractive index of the color filter 35 is about 0.94. At these interfaces, about 73% and 78% of light are extracted to the resin layer 32 side, respectively. On the other hand, since the refractive index of the resin layer 32B is higher than the refractive index of the color filter 35, total reflection does not occur at this interface, and almost all light can be extracted to the resin layer 32B side.

Further, the behavior of light at the interface 38 between the resin layer 32 and the glass substrate 30 is as follows. That is, although the refractive index of the glass substrate 30 is lower than any of the refractive indexes of the resin layers 32R, 32G, and 32B, the interface 38 has an uneven shape, so that total reflection hardly occurs. Therefore, light is efficiently extracted from the resin layer 32 to the glass substrate 30. Further, the refractive index difference between the resin layer 32 and the glass substrate 30 is the largest in the blue light emitting region 40B, and then decreases in the order of the green light emitting region 40G and the red light emitting region 40R.
The degree of light scattering at the interface 38 is greatest for blue light.

If attention is paid to the interfaces 37 and 38 in this way, the behavior of light before and after the interface 37 is the same as that of the organic EL device 1 of the first embodiment.
Functions and effects similar to those of the L device 1 can be obtained. In other words, the display characteristics of the organic EL device 1A have the first characteristic that the light emission efficiency of blue is high and a good white balance can be realized due to this, and the second characteristic that it has a wide viewing angle characteristic. Have both. Organic E
The L device 1A can realize a long life based on the first feature.

The resin layer 32 may be formed by coating the resin layers 32R, 32G, and 32B by three photolithography processes, or by applying a silica-based coating agent resin material or an epoxy-based resin material over the entire surface. After being attached, the resin layer 32 is shielded from light with a photomask.
800 mJ, 1000 mJ, and 2000 mJ in the areas corresponding to R, 32G, and 32B, respectively.
For example, a method of changing the refractive index for each light emitting region 40 by irradiating the ultraviolet ray can be used.

(Third embodiment)
Subsequently, an organic EL device 1B according to a third embodiment of the present invention will be described with reference to a cross-sectional view of FIG. The configuration of the organic EL device 1B is the same as that of the first embodiment for the element substrate.
It is the same as that of the L device 1, and only the configuration of the color filter substrate is different. For this reason, below, it demonstrates centering on difference with the organic EL apparatus 1. FIG.

The color filter substrate of the organic EL device 1B is provided on the glass substrate 30 with the color filter 35.
The overcoat 36 made of resin is laminated in this order. The color filter 35 includes a color filter 35R in the red light emission region 40R, a color filter 35G in the green light emission region 40G, and a color filter 35B in the blue light emission region 40B. Unlike the color filter 34 of the first embodiment, these color filters 35 The refractive indexes are all equal to 1.48. Further, the surface of the color filter 35 is intentionally roughened by a plasma ashing process, and irregularities having a height of about 0.01 to 0.5 μm are formed. Therefore, the interface 38 between the color filter 35 and the overcoat 36 has an uneven shape.

The overcoat 36 includes an overcoat 36R in the red light emitting region 40R, an overcoat 36G in the green light emitting region 40G, and an overcoat 36B in the blue light emitting region 40B. The refractive indexes of the overcoats 36R, 36G, and 36B are 1.
60, 1.70, 1.85 and different from each other. The refractive index of the adhesive 28 is 1.80. In the present embodiment, the overcoat 36 corresponds to the “first functional layer” of the present invention, the color filter 35 corresponds to the “second functional layer”, and the adhesive 28 corresponds to the “third functional layer”.

In the organic EL device 1B having such a configuration, when attention is paid to the interface 37 between the adhesive 28 and the overcoat 36 and the interface 38 between the overcoat 36 and the color filter 35, the magnitude relationship between the refractive indexes of the layers before and after the first is the first. Since it is the same as the organic EL device 1 of the first embodiment, the behavior of light transmitted through the interfaces 37 and 38 is the same as that of the organic EL device 1. Therefore, the same operations and effects as those of the organic EL device 1 can be obtained also by the organic EL device 1B of the present embodiment. In other words, the display characteristics of the organic EL device 1B have the first characteristic that the light emission efficiency of blue is high and a good white balance can be realized due to this, and the second characteristic that it has a wide viewing angle characteristic. Have both. Further, the organic EL device 1B can realize a long lifetime based on the first feature.

The overcoat 36 can be formed by a method similar to the method for forming the resin layer 32 in the second embodiment.

(Fourth embodiment)
Next, an organic EL device 1C according to a fourth embodiment of the present invention will be described with reference to a cross-sectional view of FIG. The configuration of the organic EL device 1C is the same as that of the first embodiment for the element substrate.
This is the same as the L device 1. For this reason, below, it demonstrates centering on difference with the organic EL apparatus 1. FIG.

The organic EL device 1 </ b> C has a configuration in which an element substrate and a glass substrate 30 are bonded together with an adhesive 28. That is, the organic EL device 1C does not include a color filter, and performs color display by the function of the optical resonator on the element substrate side. The surface in contact with the adhesive 28 of the glass substrate 30 has an uneven shape as in the organic EL device 1 of the first embodiment.

The adhesive 28 has a different refractive index for each light emitting region 40. That is, the adhesive 28 includes an adhesive 28R in the red light emitting area 40R, an adhesive 28G in the green light emitting area 40G, and an adhesive 28B in the blue light emitting area 40B. The refractive indexes of the adhesives 28R, 28G, and 28B are 1. 60, 1.70, 1.85. The refractive index of the thin film sealing layer 26 in contact with the adhesive 28 on the element substrate side is 1.80. In the present embodiment, the adhesive 28 is the “first functional layer” of the present invention, the glass substrate 30 is the “second functional layer”, and the thin film sealing layer 26.
Corresponds to the “third functional layer”.

In the organic EL device 1 </ b> C having such a configuration, the interface 37 between the thin film sealing layer 26 and the adhesive 28.
If attention is paid to the interface 38 between the adhesive 28 and the glass substrate 30, the magnitude relationship between the refractive indexes of the layers before and after that is the same as that of the organic EL device 1 of the first embodiment. The behavior of transmitted light is the same as that of the organic EL device 1. Therefore, the organic EL device 1 of the present embodiment
Also with C, the same operations and effects as those of the organic EL device 1 can be obtained. In other words, organic E
The display characteristics of the L device 1 </ b> C have both a first characteristic that the light emission efficiency of blue is high and a good white balance can be realized due to this, and a second characteristic that it has a wide viewing angle characteristic. Further, the organic EL device 1 </ b> C can achieve a long lifetime based on the first feature.

Table 6 shows data related to blue luminous efficiency and white balance in the organic EL device 1C.
Shown in

The upper part of Table 6 shows an organic EL device having a conventional structure, that is, an organic EL device in which the surface of the glass substrate 30 has no irregularities and the refractive index of the adhesive 28 is uniform compared to the structure of the organic EL device 1C. The middle stage is a characteristic when the surface of the glass substrate 30 is uneven as in the present embodiment and the refractive indexes of the adhesives 28R, 28G, and 28B are different from each other from the conventional configuration. . As a result, the blue luminous efficiency is increased from 2.5 Cd / m ² to 7.0 Cd / m ² , approximately 2.
It turns out that it is improving 8 times.

As described above, in the middle configuration of Table 6, the blue light emission efficiency has been greatly improved. Therefore, the optical path length or interference condition of the optical resonator is changed while maintaining the blue light emission luminance at a certain level. Fine adjustment to increase the blue color purity. The organic EL device 1 </ b> C according to the present embodiment that has been subjected to such fine adjustment from the middle configuration of Table 6 has its characteristics shown in the lower data of Table 6. From these data, it can be seen that the blue color efficiency and color reproducibility are improved, although the blue luminous efficiency is slightly reduced to 5.0 Cd / m ² . Furthermore, the color coordinates of white when the organic EL element 70 in each light emitting region 40 is driven with an equal current are also (0.32, 0.3).
4) The white point is closer and the white balance is improved.

By improving the white balance in this way, the same principle as in the first embodiment,
The lifetime of the device can be extended. According to the inventors' experiment, the lifetime of the organic EL device 1C is
This is about 1.9 times higher than the conventional organic EL device.

As a method for forming the adhesive 28, a method in which the material of the adhesive 28 having a different refractive index for each light emitting region 40 is discharged onto the thin film sealing layer 26 with a dispenser or a droplet discharge device and the glass substrate 30 is bonded to the thin film sealing layer 26. Can be used.

(Fifth embodiment)
Subsequently, an organic EL device 1D according to a fifth embodiment of the present invention will be described with reference to a sectional view of FIG. The organic EL device 1D has a configuration in which the thin film sealing layer 26 is removed from the organic EL device 1C of the fourth embodiment. That is, in the organic EL device 1D, the cathode 24 and the glass substrate 30 are directly fixed by the adhesive 28, and the adhesives 28R, 28G, 28
B has the function of protecting the organic EL element 70 and the function of smoothing the step formed on the cathode 24. Here, the refractive index of the cathode 24 is 1.83. Except for these points, the configuration of the organic EL device 1D is the same as that of the organic EL device 1C of the fourth embodiment. In the present embodiment, the adhesive 28 corresponds to the “first functional layer” of the present invention, the glass substrate 30 corresponds to the “second functional layer”, and the cathode 24 corresponds to the “third functional layer”.

In the organic EL device 1D having such a configuration, when attention is paid to the interface 37 between the cathode 24 and the adhesive 28 and the interface 38 between the adhesive 28 and the glass substrate 30, the relationship between the refractive indexes of the layers before and after that is fourth. Since this is the same as the organic EL device 1C of the embodiment, the behavior of the light transmitted through the interfaces 37 and 38 is the same as that of the organic EL device 1C. Therefore, the organic EL device 1D of the present embodiment
As a result, the same actions and effects as those of the organic EL device 1C can be obtained. In other words, organic E
The display characteristics of the L device 1D have both the first characteristic that the blue light emission efficiency is high and that a good white balance can be realized due to this, and the second characteristic that it has a wide viewing angle characteristic. Further, the organic EL device 1D can realize a long lifetime based on the first feature.

(Sixth embodiment)
Subsequently, an organic EL device 1E according to a sixth embodiment of the present invention will be described with reference to a sectional view of FIG. The organic EL device 1E is a bottom emission type organic EL device,
On the substrate 10, a resin layer 32, a pixel electrode 16 as an anode, a hole transport layer 18, and an organic light emitting layer 2
0, the electron transport layer 22, and the cathode 24 are laminated in this order. The substrate 10, the pixel electrode 16, the hole transport layer 18, the organic light emitting layer 20, and the electron transport layer 22 are made of the same material as that of the organic EL device 1 of the first embodiment. The cathode 24 is made of an aluminum thin film or the like, and also has a function as a reflection film that reflects light from the organic light emitting layer 20.

The organic light emitting layer 20 includes an organic light emitting layer 20R that emits red light, an organic light emitting layer 20G that emits green light, and an organic light emitting layer 20B that emits blue light. The organic light emitting layer 20R is disposed in the red light emitting region 40R, the organic light emitting layer 20G is disposed in the green light emitting region 40G, and the organic light emitting layer 20B is disposed in the blue light emitting region 40B. The light emitted from the organic light emitting layer 20 is emitted from the cathode 24.
7 and proceeding downward in FIG. 7 directly from the organic light emitting layer 20, passing through the hole transport layer 18, the pixel electrode 16, the resin layer 32, and the substrate 10 in order. Take out to the outside.

The surface of the substrate 10 on which the resin layer 32 is formed is preliminarily frosted using hydrofluoric acid or the like to form irregularities having a height of about 0.01 to 0.5 μm. For this reason, the substrate 1
The interface 38 between 0 and the resin layer 32 has an uneven shape. The resin layer 32 includes translucent resin layers 32R, 32G, and 32B having different refractive indexes, and the resin layer 32R is a red light emitting region 4.
In 0R, the resin layer 32G is in the green light emitting region 40G, the resin layer 32B is in the blue light emitting region 40B,
Each is arranged. The refractive indexes of the resin layers 32R, 32G, and 32B are 1.65, respectively.
1.70, 1.90. The refractive index of the pixel electrode 16 is 1.80. In the present embodiment, the resin layer 32 corresponds to the “first functional layer” of the present invention, and the pixel electrode 16 corresponds to the “third functional layer”.

In the organic EL device 1E having such a configuration, an interface 37 between the pixel electrode 16 and the resin layer 32,
If attention is paid to the interface 38 between the resin layer 32 and the substrate 10, the relationship in refractive index between the layers before and after the same is the same as that of the organic EL device 1 of the first embodiment, and thus the interfaces 37 and 38 are transmitted. The behavior of light is the same as that of the organic EL device 1. Therefore, the same operations and effects as those of the organic EL device 1 can be obtained also by the organic EL device 1E of the present embodiment. That is, the organic EL device 1
The display characteristic of E has both the first characteristic that the luminous efficiency of blue is high and that a good white balance can be realized due to this, and the second characteristic that it has a wide viewing angle characteristic. Further, the organic EL device 1E can realize a long lifetime based on the first feature.

  Table 7 shows data representing viewing angle characteristics in the organic EL device 1E.

The upper part of Table 7 shows an organic EL device having a conventional configuration, that is, an organic EL device in which the surface of the substrate 10 has no unevenness and the resin layer 32 is not arranged as compared with the configuration of the organic EL device 1E. When white display is performed by adjusting the drive current so that the coordinates are (0.33, 0.33), the chromaticity coordinates when viewing the white display from the 45 ° viewing angle, and 45 ° from the front It shows the color difference between the viewing angles. On the other hand, the lower row shows similar data for the organic EL device 1E of the present embodiment. As is apparent from this table, the organic EL device 1E
It can be seen that the color difference is very small compared to the conventional configuration, and the viewing angle characteristics are greatly improved.

(Example of mounting on electronic equipment)
The organic EL device 1 to which the present invention is applied (including the organic EL devices 1A to 1E) is, for example,
It can be used by being mounted on the mobile phone 500 shown in FIG. The mobile phone 500 includes a display unit 510 and operation buttons 520. The display unit 510 can display various information including the contents input by the operation buttons 520 and the incoming call information by the organic EL device 1 incorporated therein. The cellular phone 500 can perform high-quality display on the display unit 510 by the organic EL device 1 having a good white balance and a wide viewing angle characteristic and having a long lifetime.

The organic EL device 1 to which the present invention is applied includes the mobile phone 500, a mobile computer, a digital camera, a digital video camera, an in-vehicle device, an audio device, various electronic devices such as a projector, a scanner light source, and a printer. It can be used for a line head or the like.

As mentioned above, although embodiment of this invention was described, various deformation | transformation can be added with respect to the said embodiment in the range which does not deviate from the meaning of this invention. As modifications, for example, the following can be considered.

(Modification 1)
In the first to fifth embodiments, the organic EL element 70 is configured to emit color light using interference of an optical resonator. Instead, the organic EL element 70 is similar to the sixth embodiment. Similarly, the organic light emitting layers 20R, 20G, and 20B that emit light of each color of red, green, and blue may be arranged for each light emitting region 40.

(Modification 2)
In each of the above embodiments (excluding the third embodiment), the uneven shape on the surface of the glass substrate 30 or the substrate 10 is formed by frost treatment using hydrofluoric acid or the like, but is not limited to this. Instead of the above forming method, SiO ₂ is formed on the surface of the glass substrate 30 or the substrate 10.
After forming a thin film such as SiN or acrylic resin, the thin film may be formed using a method of processing the thin film into an uneven shape.

(Modification 3)
In the third embodiment, the overcoat 36 is made of a resin, but instead of this, an inorganic thin film formed by a vacuum thin film forming method may be used. Specifically, the overcoat 36R has a material ratio of Ta ₂ O ₅ : TiO ₂ : SiO ₂ = 1: 4: 5, and the overcoat 36G has Ta ₂ O ₅ : TiO ₂ : SiO ₂ = 3: An appropriate refractive index can be obtained by forming the overcoat 36B having a material ratio of 2: 5 and a material ratio of Ta ₂ O ₅ : TiO ₂ : SiO ₂ = 4: 3: 3.

(Modification 4)
In the above embodiment, the organic light emitting layer 20 is a common light emitting layer for red, green, and blue.
Even when the light emitting layer is separately formed for each light emitting region 40 at 0, the effect can be obtained.

(Modification 5)
In the above embodiment, the film thickness of the pixel electrode 16 is changed in each light emitting region 40 as a means for setting the resonator condition, but the reflective film 12, the insulating layer 14, the hole transport layer 18, which are other layers, The effect of the resonator may be obtained by changing the material of the cathode 24 or the layer having interface reflection such as the organic light-emitting layer 20 and the electron transport layer 22 as the light-emitting layer and the film thickness of the material.

1 is a block diagram schematically showing a configuration of an organic EL device according to an embodiment of the present invention. 1 is a cross-sectional view of an organic EL device according to a first embodiment. Sectional drawing of the organic electroluminescent apparatus which concerns on 2nd Embodiment. Sectional drawing of the organic electroluminescent apparatus which concerns on 3rd Embodiment. Sectional drawing of the organic electroluminescent apparatus which concerns on 4th Embodiment. Sectional drawing of the organic electroluminescent apparatus which concerns on 5th Embodiment. Sectional drawing of the organic electroluminescent apparatus which concerns on 6th Embodiment. 1 is a perspective view of a mobile phone according to an embodiment of the present invention. Sectional drawing of the organic electroluminescent apparatus of the conventional structure.

Explanation of symbols

1, 1A, 1B, 1C, 1D, 1E ... Organic EL device, 10 ... Substrate, 12 ... Reflecting film, 14
DESCRIPTION OF SYMBOLS ... Insulating layer, 16 ... Pixel electrode, 18 ... Hole transport layer, 20 ... Organic light emitting layer as a light emitting layer, 22
... Electron transport layer, 24 ... Cathode, 26 ... Thin film sealing layer, 28 ... Adhesive, 30 ... Glass substrate, 32
... resin layer, 34, 35 ... color filter, 36 ... overcoat, 37, 38 ... interface, 4
DESCRIPTION OF SYMBOLS 0 ... Light emission area | region, 70 ... Organic EL element, 500 ... Mobile phone.

Claims (11)

An electroluminescent device having a plurality of light emitting regions, each corresponding to one of a plurality of different colors,
A substrate,
A plurality of first electrodes disposed on the substrate in correspondence with the light emitting region;
A translucent second electrode disposed opposite the first electrode;
A light emitting layer disposed between the first electrode and the second electrode;
A first functional layer disposed on the opposite side of the second electrode from the side on which the light emitting layer is disposed;
A second functional layer disposed on and in contact with the first functional layer on the first functional layer;
The interface between the first functional layer and the second functional layer has an uneven shape that scatters light emitted from the light emitting layer,
The first functional layer is characterized in that a refractive index in the light emitting region corresponding to one of the plurality of different colors is different from a refractive index in the light emitting region corresponding to another color. apparatus. The electroluminescent device according to claim 1,
The electroluminescent device according to claim 1, wherein a refractive index of the first functional layer is larger than a refractive index of the second functional layer in any of the light emitting regions. The electroluminescent device according to claim 2,
The difference between the refractive index of the first functional layer and the refractive index of the second functional layer is 0.03 or more and 1.00 or less in any of the light emitting regions. An electroluminescent device having a plurality of light emitting regions, each corresponding to one of a plurality of different colors,
A substrate,
A first functional layer disposed on and in contact with the substrate;
A plurality of translucent first electrodes disposed on the first functional layer so as to correspond to the light emitting region;
A second electrode disposed opposite the first electrode;
A light emitting layer disposed between the first electrode and the second electrode,
The interface between the first functional layer and the substrate has an uneven shape that scatters the light emitted from the light emitting layer,
The first functional layer is characterized in that a refractive index in the light emitting region corresponding to one of the plurality of different colors is different from a refractive index in the light emitting region corresponding to another color. apparatus. The electroluminescent device according to claim 4,
The electroluminescent device according to claim 1, wherein a refractive index of the first functional layer is larger than a refractive index of the substrate in any of the light emitting regions. The electroluminescent device according to claim 5,
The difference between the refractive index of the first functional layer and the refractive index of the substrate is 0 in any light emitting region.
. The electroluminescent device is characterized by being not less than 03 and not more than 1.00. The electroluminescence device according to any one of claims 1 to 6,
A third functional layer disposed in contact with a surface of the first functional layer opposite to the interface having the concavo-convex shape;
The ratio of the refractive index of the first functional layer to the refractive index of the third functional layer is greater than 0.83 and less than or equal to 1.50 in any of the light emitting regions. The electroluminescence device according to any one of claims 1 to 7,
The light emitting region includes a red light emitting region from which red light emission is obtained, a green light emitting region from which green light emission is obtained, and a blue light emitting region from which blue light emission is obtained,
The electroluminescent device according to claim 1, wherein the first functional layer has a refractive index in the blue light emitting region that is different from a refractive index in the red light emitting region and a refractive index in the green light emitting region. The electroluminescent device according to claim 8,
The electroluminescent device according to claim 1, wherein the first functional layer has different refractive indexes in the red light emitting region, the green light emitting region, and the blue light emitting region. The electroluminescent device according to claim 8 or 9, wherein
The electroluminescent device according to claim 1, wherein the first functional layer has a refractive index in the blue light emitting region that is higher than a refractive index in the red light emitting region and a refractive index in the green light emitting region. An electronic device comprising the electroluminescence device according to claim 1.

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