JP4822243B2 - LIGHT EMITTING ELEMENT AND ORGANIC ELECTROLUMINESCENT LIGHT EMITTING ELEMENT - Google Patents

Description

  The present invention relates to a light emitting element with high light extraction efficiency. In particular, the present invention relates to a light-emitting element with high light extraction efficiency of light emitted from an organic EL layer in an organic electroluminescence (hereinafter, “electroluminescence” is abbreviated as “EL”) light-emitting element.

  Organic EL light-emitting elements are highly expected as self-light-emitting elements as video display devices such as displays and surface light sources. When an organic EL light emitting element is used as an image display device, there are a part color method that emits light in a single color and a full color method that has a region that emits light in three primary colors of red (R), green (G), and blue (B). is there. When used as a surface light source, it is configured as a thin film.

  Such an organic EL light emitting element is generally produced by sequentially laminating a transparent electrode as an anode, an organic EL layer, and a metal electrode as a cathode on a transparent substrate such as a glass substrate. Due to the voltage applied between the transparent electrode and the metal electrode, the electrons supplied from the cathode and the holes supplied from the anode are recombined in the organic EL layer, and the excitons generated thereby are excited. EL light is emitted when shifting from the ground state to the ground state. The light emitted from the EL is transmitted through the transparent electrode and taken out from the transparent substrate side.

  Such an organic EL light emitting device is expected to have low light extraction efficiency. That is, since the refractive index of ITO (Indium Tin Oxide) used as the transparent electrode is about 2.0 which is higher than the refractive index 1.5 of the glass substrate used as the transparent substrate, from the transparent electrode to the glass substrate. Most of the light that goes is a transparent electrode waveguide mode that propagates in the vicinity of the transparent electrode, and is not emitted from the transparent electrode to the glass substrate. FIG. 1 shows a simulation result of an electric field distribution in a transparent electrode waveguide mode confined in a transparent electrode. In FIG. 1, according to the distance from the metal electrode, following the organic EL layers Alq3 and PVK, the refractive index distribution of ITO and the glass substrate is shown by a broken line, and the transparent electrode waveguide mode of light having an emission wavelength of 524 nm is shown. The electric field strength is indicated by a solid line. As can be seen from FIG. 1, the transparent electrode waveguide mode is confined in ITO having a high refractive index and cannot be taken out to the outside although the seepage of the effective wavelength is recognized.

  Furthermore, since the refractive index of the glass substrate is as high as about 1.5 compared with the refractive index of air, a transparent substrate waveguide in which most of the light traveling from the transparent electrode to the glass substrate propagates in the glass substrate. It becomes a mode and is not emitted into the air from the glass substrate. As a result, most of the light emitted from the organic EL layer becomes the transparent electrode waveguide mode or the transparent substrate waveguide mode, and the light extraction efficiency is lowered.

  In addition, in this application, light extraction efficiency means the ratio of the photon which can be taken out of the organic EL light emitting element with respect to the photon emitted from the organic EL layer.

  In the present application, the waveguide mode refers to the state of electromagnetic waves propagating in the waveguide. The radiation mode refers to a state of electromagnetic waves that are not localized in the waveguide.

  Since the actual light extraction efficiency is difficult to measure, the calculation has to rely on simulation. However, since the thickness of the transparent electrode and the organic EL layer is about the same as or thinner than the effective wavelength of the light emitted from the organic EL layer, it is known that a simple geometric optical technique has a large error. Therefore, various calculation methods other than geometric optics have been tried. As a result of simulation using the finite time domain difference method, the inventors have found that the transparent electrode waveguide mode is not changed even when the layer thickness of the transparent electrode is changed from 50 nm to 200 nm and the layer thickness of the organic EL layer is changed from 20 nm to 80 nm. Clearly, 40-50% of the light emitted from the organic EL layer, the transparent substrate waveguide mode is about 25-35%, and the light extraction efficiency of the light emitted from the glass substrate is about 15-30%. did.

In this application, the effective wavelength means the wavelength of light in the propagation medium,
Effective wavelength = wavelength in vacuum / refraction index of propagation medium.

  Conventionally, as a method for improving light extraction efficiency with an organic EL light emitting element, a technique in which a condensing lens is provided at the boundary between a transparent electrode and a transparent substrate has been disclosed (for example, see Patent Document 1). FIG. 2 shows a conventional technique in which a condensing lens is provided at the boundary between the transparent electrode and the transparent substrate. 81 is a glass substrate, 82 is a transparent electrode, 83 is an organic EL layer, and 84 is a condensing lens. This is a structure in which a plurality of condensing lenses 84 as light angle conversion means convert the incident angle of light that is totally reflected from the light emitted from the organic EL layer 83 to a small angle and extract the light. Is.

However, as shown in FIG. 2, when the condensing lens 84 formed on the upper surface of the glass substrate 81 is used, the organic EL layer 83 (point A in FIG. 2) located immediately below the center of the condensing lens 84 is used. For light, the proportion of light that is totally reflected can be reduced, but for light from the organic EL layer 83 (point B in FIG. 2) that is off the center of the lens. Rather results in increasing the proportion of light that is totally reflected.
JP 2002-260845 A

  The inventors paid attention to the fact that most of the light emitted from the organic EL layer is in the transparent electrode waveguide mode or the transparent substrate waveguide mode from the simulation result of the light extraction efficiency. That is, if the transparent electrode waveguide mode is converted into a radiation mode that radiates from the transparent electrode to the transparent substrate, or the transparent substrate waveguide mode is converted into a radiation mode that radiates from the transparent substrate to the outside, the light extraction efficiency is improved.

  Accordingly, the inventors have invented a mode conversion means for converting a transparent electrode waveguide mode or a transparent substrate waveguide mode, which is a waveguide mode, into a radiation mode by utilizing the wave behavior of light. In order to solve the low light extraction efficiency of a conventional light emitting element such as an organic EL light emitting element, the present invention aims to improve the light extraction efficiency from the light emitting element such as an organic EL light emitting element using a mode conversion means. For the purpose.

  The basic principle of the invention for achieving the above-described object will be described with reference to FIG. In FIG. 3, 11 is a substrate, 12 is a light emitting layer, 21 is a radiation mode, 22 is a waveguide mode, 23 is a radiation mode, 24 is a waveguide mode, and the light emitting layer 12 is formed on the substrate 11. The light emitted from the light emitting layer 12 is transmitted through the substrate 11 and emitted to the outside. Since the substrate 11 generally has a higher refractive index than the outside air, the light emitted from the light emitting layer 12 becomes the radiation mode 21 if the incident angle from the substrate 11 to the outside air is less than the critical angle. Radiated to the outside. However, when the incident angle from the substrate 11 to the external air is greater than or equal to the critical angle, the light is totally reflected at the boundary between the substrate 11 and the external air to become the waveguide mode 22.

  Therefore, a mode conversion means for converting the waveguide mode to the radiation mode is provided in a region where light that becomes the waveguide mode propagates. In FIG. 3, a regular refractive index distribution is formed at the interface between the substrate 11 and the light emitting layer 12. For example, if the refractive index of the substrate 11 is 1.5 and the refractive index of the light emitting layer 12 is different from 1.7, it is possible to form regular refraction only by forming irregularities at the boundary between the substrate 11 and the light emitting layer 12. A rate distribution can be formed. If the formed irregularities have a period in which the propagation of light in the waveguide mode is prohibited, ideally, all the waveguide modes 22 are converted to radiation modes 23. Actually, since it is difficult to obtain a refractive index distribution in which the propagation is completely prohibited, a part of the waveguide mode 22 is converted into the radiation mode 23 by suppressing the propagation, and one of the waveguide modes 22 is converted. The part remains in the waveguide mode 24 without being converted.

  Specifically, the first invention of the present application is a light emitting element having at least a light emitting layer on a substrate, the inside of the substrate, the inside of the light emitting layer, the interface between the substrate and the outside, the substrate and the substrate. It is a light emitting device comprising a mode conversion means for converting from a waveguide mode to a radiation mode in at least one of the interface of the light emitting layer and the interface between the light emitting layer and the outside.

  Alternatively, in the case of a light emitting device having at least a light emitting layer and one or more waveguide layers on a substrate, the inside of the substrate, the inside of the light emitting layer, the inside of the waveguide layer, the substrate and the substrate Interface with the outside, interface between the substrate and the light emitting layer, interface between the light emitting layer and the outside of the light emitting layer, interface between the substrate and the waveguide layer, interface between the light emitting layer and the waveguide layer A light emitting device comprising mode conversion means for converting from a waveguide mode to a radiation mode in at least one of an interface between the waveguide layer and the outside of the waveguide layer, or an interface between the waveguide layer and the waveguide layer It is.

  In the light emitting element, a part of the light emitted from the light emitting layer becomes a radiation mode and is radiated to the outside of the light emitting element, and the rest becomes a waveguide mode. It is converted into a radiation mode by the means and emitted to the outside of the light emitting element. Therefore, the light extraction efficiency of the light emitting element can be improved.

  The second invention of the present application is an organic electroluminescence light-emitting element having, on a substrate, at least a first electrode, an organic electroluminescence layer, and a second electrode facing the first electrode in order. The interior of the substrate, the interior of the first electrode, the interior of the organic electroluminescent layer, the interior of the second electrode, the interface between the substrate and the exterior of the substrate, the substrate and the first An interface with an electrode, an interface between the first electrode and the organic electroluminescent layer, an interface between the organic electroluminescent layer and the second electrode, or an interface between the second electrode and the second electrode It is an organic electroluminescence light emitting element provided with a mode conversion means for converting from a waveguide mode to a radiation mode in at least one of the interfaces with the outside.

  Alternatively, at least a first electrode, an organic electroluminescent layer, and a second electrode facing the first electrode are sequentially provided on the substrate, and one of the electrodes on the substrate is 1 In the case of an organic electroluminescence light-emitting device having the above waveguide layer, the inside of the substrate, the inside of the first electrode, the inside of the organic electroluminescence layer, the inside of the second electrode, the waveguide The inside of the layer, the interface between the substrate and the outside of the substrate, the interface between the substrate and the first electrode, the interface between the first electrode and the organic electroluminescent layer, and the organic electroluminescent layer The interface between the second electrode, the interface between the second electrode and the outside of the second electrode, the interface between the substrate and the waveguide layer, and the interface between the first electrode and the waveguide layer , An interface between the organic electroluminescent layer and the waveguide layer, and between the second electrode and the waveguide layer An organic layer comprising a mode conversion means for converting from a waveguide mode to a radiation mode at least one of a plane, an interface between the waveguide layer and the outside of the waveguide layer, or an interface between the waveguide layer and the waveguide layer An electroluminescent light emitting device.

  In the organic EL light emitting device, part of the light emitted from the organic EL layer becomes a radiation mode and is radiated to the outside of the organic EL light emitting device, and the rest becomes a waveguide mode. The emitted light is also changed into a radiation mode by the mode conversion means and emitted outside the organic EL light emitting element. Therefore, the light extraction efficiency of the organic EL light emitting element is improved.

  The organic EL layer may include a hole injection layer, a hole transport layer, an organic EL light emitting layer, an electron injection layer, and an electron transport layer. The hole injection layer has a function of facilitating injection of holes from the hole injection electrode, and the hole transport layer has a function of stably transporting holes. The electron injection layer has a function of facilitating injection of electrons from the electron injection electrode, and the electron transport layer has a function of stably transporting electrons. These layers increase holes and electrons injected into the organic EL light-emitting layer, exhibit a confinement effect, and improve the light emission efficiency. The organic EL light emitting layer contains a fluorescent material which is a compound having a light emitting function, and emits light by an EL phenomenon. The same applies to the following description.

  The waveguide layer does not mean a material or a structure, but means a layer in which light emitted from the organic EL layer becomes a waveguide mode. In particular, when the refractive indexes of the layers on both sides are relatively low, the surface in contact with the layers on both sides is reflected beyond the critical angle, so that it tends to be a waveguide layer. The same applies to the following description.

  In the second invention of the present application, the second electrode is a transparent electrode, a thin film metal electrode, or an electrode in which a thin film metal is disposed on the transparent electrode and the organic electroluminescence layer side of the transparent electrode. Luminescent light emitting elements are also included.

  By using the second electrode as a transparent electrode, light emitted from the organic EL layer can be extracted from the side opposite to the substrate. A so-called top emission type organic EL light emitting device can be obtained. The second electrode may be a thin film metal electrode to improve translucency. If the second electrode is on the anode side, injection of holes is easy even if the second electrode is a transparent electrode, but if the second electrode is on the cathode side, injection of electrons is difficult even if the second electrode is a transparent electrode. Become. In this case, the problem can be solved by forming a thin metal film with easy electron injection between the transparent electrode and the organic EL layer.

  The second invention of the present application further includes an organic functional layer provided with a mode conversion means for converting from a waveguide mode to a radiation mode on the outer surface of the substrate or the outer surface of the second electrode. Luminescent light emitting elements are also included.

  By having an optical functional layer having mode conversion means for converting the waveguide mode to the radiation mode on the outer surface of the substrate, the light emitted from the organic EL layer toward the substrate becomes the waveguide mode. However, it is converted into a radiation mode and emitted to the outside of the organic EL light emitting element. This is effective for a so-called bottom emission type organic EL light emitting element in which light emitted from the organic EL layer is extracted from the substrate side. In addition, by having an optical functional layer having mode conversion means for converting from the waveguide mode to the radiation mode on the outer surface of the second electrode, light directed toward the second electrode among the light emitted from the organic EL layer Is converted to a radiation mode even if it becomes a waveguide mode, and is emitted to the outside of the organic EL light emitting element. This is effective for a so-called top emission type organic EL light emitting element in which light emitted from the organic EL layer is extracted from the side opposite to the substrate. Therefore, the light extraction efficiency of the organic EL light emitting element is improved. The mode conversion means is provided inside the optical functional layer or at the interface of the optical functional layer.

  The optical functional layer is made of a material that transmits light emitted from the organic EL layer, and has a mode conversion means for converting the waveguide mode to the radiation mode inside or at the interface. If a mode conversion means for converting the waveguide mode to the radiation mode is provided in a part of the waveguide layer, it functions as an optical functional layer.

  The third invention of the present application includes, on the substrate, at least a first electrode, an organic electroluminescence layer, a second electrode that is transparent to the first electrode, and a protective film in order. An organic electroluminescent light emitting device comprising: the inside of the substrate; the inside of the first electrode; the inside of the organic electroluminescent layer; the inside of the second electrode; the inside of the protective film; The interface between the outside of the substrate, the interface between the substrate and the first electrode, the interface between the first electrode and the organic electroluminescent layer, and between the organic electroluminescent layer and the second electrode At least one of an interface, an interface between the second electrode and the protective film, or an interface between the protective film and the outside of the protective film, comprising a mode conversion means for converting from a waveguide mode to a radiation mode. It is a sense light emitting element.

  Or, on the substrate, at least a first electrode, an organic electroluminescence layer, a second electrode that is transparent to the first electrode, and a protective film, and a protective film in this order, and In the case of an organic electroluminescent light emitting device having one or more waveguide layers on any of the substrates, the inside of the substrate, the inside of the first electrode, the inside of the organic electroluminescent layer, the first The inside of the second electrode, the inside of the protective film, the inside of the waveguide layer, the interface between the substrate and the outside of the substrate, the interface between the substrate and the first electrode, the first electrode and the organic An interface with the electroluminescent layer, an interface between the organic electroluminescent layer and the second electrode, an interface between the second electrode and the protective film, an interface between the protective film and the outside of the protective film, An interface between the substrate and the waveguiding layer, an interface between the first electrode and the waveguiding layer, the organic electro The interface between the minence layer and the waveguide layer, the interface between the second electrode and the waveguide layer, the interface between the protective film and the waveguide layer, and between the waveguide layer and the outside of the waveguide layer An organic electroluminescence light-emitting device comprising mode conversion means for converting from a waveguide mode to a radiation mode in at least one of an interface or an interface between the waveguide layer and the waveguide layer.

  When the second electrode is a translucent electrode and the light emitted from the organic EL layer is taken out from the opposite side of the substrate, the so-called top emission type organic EL light emitting device is protected on the second electrode side. It is preferable to provide a film. The protective film can be expected to prevent contact with the second electrode and prevent oxidation of the organic EL layer. By providing mode conversion means inside the protective film or at the interface of the protective film, the light in the waveguide mode is also converted into the radiation mode and emitted to the outside of the organic EL light emitting element. Therefore, the light extraction efficiency of the organic EL light emitting element is improved.

  The third invention of the present application further comprises an optical functional layer having a mode conversion means for converting from a waveguide mode to a radiation mode on the outer surface of the substrate or the outer surface of the protective layer. A light emitting element is also included.

  By having an optical functional layer having mode conversion means for converting the waveguide mode to the radiation mode on the outer surface of the substrate, the light emitted from the organic EL layer toward the substrate becomes the waveguide mode. However, it is converted into a radiation mode and emitted to the outside of the organic EL light emitting element. This is effective for a so-called bottom emission type organic EL light emitting element in which light emitted from the organic EL layer is extracted from the substrate side. In addition, by having an optical functional layer having a mode conversion means for converting the waveguide mode to the radiation mode on the outer surface of the protective layer, light directed toward the protective layer out of the light emitted from the organic EL layer is guided. Even if it becomes a wave mode, it is converted into a radiation mode and emitted outside the organic EL light emitting element. This is effective for a so-called top emission type organic EL light emitting element in which light emitted from the organic EL layer is extracted from the side opposite to the substrate. Therefore, the light extraction efficiency of the organic EL light emitting element is improved. The mode conversion means is provided inside the optical functional layer or at the interface of the optical functional layer.

  The fourth invention of the present application is an organic electroluminescence light-emitting device comprising, on a transparent substrate, at least a transparent electrode, an organic electroluminescence layer, and a metal electrode opposed to the transparent electrode in order. The inside of the transparent electrode, the inside of the organic electroluminescent layer, the inside of the metal electrode, the interface between the transparent substrate and the outside of the transparent substrate, the interface between the transparent substrate and the transparent electrode, the transparent A radiation mode from a waveguide mode to at least one of an interface between the electrode and the organic electroluminescent layer, an interface between the organic electroluminescent layer and the metal electrode, or an interface between the metal electrode and the outside of the metal electrode It is an organic electroluminescent light emitting element provided with the mode conversion means to convert into.

  Alternatively, at least a transparent electrode, an organic electroluminescence layer, and a metal electrode facing the transparent electrode are sequentially provided on the transparent substrate, and one or more waveguides are provided on the transparent substrate. In the case of an organic electroluminescent light emitting device having a layer, the inside of the transparent substrate, the inside of the transparent electrode, the inside of the organic electroluminescent layer, the inside of the metal electrode, the inside of the waveguide layer, the transparent substrate And the outside of the transparent substrate, the interface between the transparent substrate and the transparent electrode, the interface between the transparent electrode and the organic electroluminescent layer, the interface between the organic electroluminescent layer and the metal electrode, The interface between the metal electrode and the outside of the metal electrode, the interface between the transparent substrate and the waveguide layer, the interface between the transparent electrode and the waveguide layer, the interface between the organic electroluminescent layer and the waveguide layer The metal electrode and the waveguiding layer At least one of the interface of the waveguide, the interface between the waveguide layer and the outside of the waveguide layer, or the interface between the waveguide layer and the waveguide layer is provided with a mode conversion means for converting from the waveguide mode to the radiation mode. It is an organic electroluminescence light emitting element.

  In the organic EL light emitting element, part of the light emitted from the organic EL layer becomes a radiation mode and is radiated to the outside of the organic EL light emitting element, and the rest becomes a waveguide mode. The emitted light is also changed into a radiation mode by the mode conversion means and emitted outside the organic EL light emitting element. Therefore, the light extraction efficiency of the organic EL light emitting element is improved.

  According to a fourth aspect of the present invention, the organic electroluminescent device further comprises an optical functional layer having a mode conversion means for converting from a waveguide mode to a radiation mode on the outer surface of the transparent substrate or the outer surface of the metal electrode. A sense light emitting element is also included.

  By having an optical functional layer provided with a mode conversion means for converting the waveguide mode to the radiation mode on the outer surface of the transparent substrate, light directed toward the transparent substrate among the light emitted from the organic EL layer is guided mode. Even if it becomes, it will be converted into a radiation mode and radiated | emitted to the exterior of an organic electroluminescent light emitting element. This is effective for a so-called bottom emission type organic EL light emitting element in which light emitted from the organic EL layer is extracted from the transparent substrate side. In addition, by having an optical functional layer provided with a mode conversion means for converting the waveguide mode to the radiation mode on the outer surface of the metal electrode, light directed toward the metal electrode among the light emitted from the organic EL layer is guided. Even if it becomes a wave mode, it is converted into a radiation mode and emitted outside the organic EL light emitting element. This is effective for a so-called top emission type organic EL light emitting element in which light emitted from the organic EL layer is extracted from the side opposite to the transparent substrate. Therefore, the light extraction efficiency of the organic EL light emitting element is improved. The mode conversion means is provided inside the optical functional layer or at the interface of the optical functional layer.

  The waveguide modes in the invention include a transparent electrode waveguide mode that propagates through the transparent electrode and a transparent substrate waveguide mode. The transparent electrode waveguide mode includes not only the transparent electrode but also a waveguide mode integrated with the inside of the organic EL layer. Because the thickness of the transparent electrode and the thickness of the organic EL layer is thinner than the effective wavelength, and there is a seepage from the transparent electrode to the organic EL layer and the transparent substrate, it is not necessarily strictly propagation in the transparent electrode. is there. The transparent substrate waveguide mode is a waveguide mode having the strongest electric field strength mainly in the transparent substrate. The same applies to the following inventions.

  In the conversion from the guided mode to the radiation mode in the above invention, when the refractive index of the inner layer is higher than the refractive index of the outer layer, the guided mode of the inner layer is changed to the guided mode of the outer layer. Conversion is also included. This is because even if the guided mode of the inner layer is mode-converted and radiated, a part is radiated to the outside through the outer layer, but a part becomes the guided mode of the outer layer. For example, when the refractive index of the transparent electrode is 2.0, the refractive index of the transparent substrate is 1.5, and the refractive index outside the transparent substrate is 1.0, the conversion from the transparent electrode waveguide mode to the radiation mode is necessary. Conversion from the transparent electrode waveguide mode to the radiation mode that is radiated to the outside through the transparent substrate and conversion from the transparent electrode waveguide mode to the radiation mode is radiated from the transparent electrode into the transparent substrate. Also included is a conversion to a radiation mode that becomes a transparent substrate waveguide mode propagating in the transparent substrate. The same applies to the following inventions.

  A fifth invention of the present application is the optical structure according to the first invention of the present application to the fourth invention of the present application, wherein the mode conversion means has a regular refractive index distribution in a one-dimensional, two-dimensional, or three-dimensional direction. This is an organic EL light emitting device characterized by the following.

  The light extraction efficiency of the organic EL light-emitting element is improved by the optical structure having a regular refractive index distribution in the one-dimensional, two-dimensional, or three-dimensional direction of the fifth invention of the present application.

Another invention of the present application is the organic electroluminescent light emitting device according to the fifth invention, wherein the regularity is a period of about an effective wavelength of light emitted from the organic electroluminescent layer.
With a period of about the effective wavelength, it is possible to effectively interfere with the light emitted from the organic EL layer, and the light extraction efficiency of the organic EL light emitting element is improved.

  In the present application, the term “effective wavelength” refers to a length that is ¼ to 5 times the effective wavelength.

According to another invention of the present application, in the above invention, the organic electroluminescent light-emitting element comprises two or more mode conversion means, and the regularity of the two or more mode conversion means is the same period. It is a luminescence light emitting element.
When the organic EL light emitting element has two or more mode conversion means, the light emitting efficiency of the organic EL light emitting element is improved by sequentially converting from the waveguide mode to the radiation mode without staying in one layer.

According to another invention of the present application, in the fifth invention of the present application, the regularity has a fluctuation of one quarter or less of a period with respect to a period of an effective wavelength of light emitted from the organic electroluminescent layer. It is an organic electroluminescence light emitting element.
By giving periodicity and fluctuation to the regularity, it is possible to effectively interfere with light having a wavelength broadening emitted from the organic EL layer, and the light extraction efficiency of the organic EL light emitting element is improved. Further, light from the organic EL light emitting element can be emitted not only in a specific direction but also in a wide angle, and directivity can be relaxed.

According to another invention of the present application, in the above invention, the mode conversion means has at least two or more optical structures having a regular refractive index distribution in a two-dimensional direction, and the regularity of the optical structure is the optical structure. It is an organic electroluminescent light emitting element characterized by having a different period within the range of the fluctuation for each specific structure.
It is possible to select the optimum structure for the mode conversion from the guided mode to the radiation mode in each layer, or to efficiently convert the mode from the guided mode to the radiation mode in cooperation with optical structures with different periods. .

Another invention of the present application is the organic electroluminescent light emitting device according to the above invention, wherein the two or more optical structures are formed in the same two-dimensional plane.
By forming two or more optical structures in the same two-dimensional plane, different periods can be realized simultaneously, and mode conversion from the waveguide mode to the radiation mode can be performed more efficiently.

According to another invention of the present application, in the fifth invention of the present application, the regularity is a period of about an effective wavelength of light emitted from the organic electroluminescent layer, and is not more than a quarter of a period with respect to a period of an effective wavelength An organic electroluminescence light-emitting element characterized in that fluctuation is mixed.
By mixing fluctuations in the periodic regularity, it is possible to effectively interfere with light having a wavelength broadening emitted from the organic EL layer, and the light extraction efficiency of the organic EL light emitting element is improved.

Another invention of the present application is the organic electroluminescence light-emitting element according to the fifth invention of the present application, wherein the periodicity gradually changes in period.
By gradually changing the period, it is possible to more effectively interfere with light having a wavelength broadening that is emitted from the organic EL layer, and light extraction efficiency of the organic EL light emitting element. Will improve.

According to another invention of the present application, in the fifth invention of the present application, the regular refractive index distribution in the two-dimensional direction fills the plane with a square lattice arrangement, a triangular lattice arrangement, a honeycomb lattice arrangement, or a finite number of unit elements. An organic electroluminescence light-emitting element characterized by having an arrangement capable of being formed, or a combination thereof.
Since a regular refractive index distribution can be realized in a two-dimensional direction, the light extraction efficiency of the organic EL light emitting element is improved.

Another invention of the present application is characterized in that, in the fifth invention of the present application, the regular refractive index distribution is formed of a material having a higher refractive index than a material having no regular refractive index distribution. It is an organic electroluminescence light emitting element.
Since a regular refractive index distribution can be formed with a material having a higher refractive index than the surrounding material, the light extraction efficiency of the organic EL light-emitting element is improved.

Another invention of the present application is the organic electroluminescence light-emitting element according to the above invention, wherein the material having a high refractive index is transmissive to light emitted from the organic EL layer.
If the light emitted from the organic EL layer is transmissive, light loss can be reduced with respect to the waveguide mode, and the light extraction efficiency of the organic EL light-emitting element is improved.

Another invention of the present application is characterized in that, in the fifth invention of the present application, the regular refractive index distribution is formed of a material having a refractive index lower than that of the material in the case where the regular refractive index distribution is not provided. It is an organic electroluminescence light emitting element.
Since a regular refractive index distribution can be formed with a material having a lower refractive index than the surrounding material, the light extraction efficiency of the organic EL light-emitting element is improved.

Another invention of the present application is the organic electroluminescence light-emitting element according to the above invention, wherein the material having a low refractive index is transmissive to light emitted from the organic EL layer.
If the light emitted from the organic EL layer is transmissive, light loss can be reduced with respect to the waveguide mode, and the light extraction efficiency of the organic EL light-emitting element is improved.

Another invention of the present application is the organic electroluminescent light emitting device according to the invention, wherein the material having the low refractive index is a gas.
Since gas generally has a refractive index of about 1, it can be used as a material having a low refractive index with respect to a transparent electrode or a transparent substrate, and forms a regular refractive index distribution with a material having a low refractive index. Therefore, the light extraction efficiency of the organic EL light emitting element is improved.

Another invention of the present application is the organic electroluminescence light-emitting element according to the above invention, wherein the gas is air or an inert gas.
If these gases are confined when producing a transparent electrode, a transparent substrate, etc. in the air or in an inert gas, an organic EL light emitting device with high light extraction efficiency can be easily produced.

  Another invention of the present application is the fifth invention of the present application, wherein the interface between the substrate and the outside of the substrate, the interface between the substrate and the first electrode, the interface between the first electrode and the organic electroluminescent layer. , An interface between the organic electroluminescence layer and the second electrode, an interface between the second electrode and the outside of the second electrode, an interface between the substrate and the waveguide layer, the first electrode And the waveguide layer, the interface between the organic electroluminescence layer and the waveguide layer, the interface between the second electrode and the waveguide layer, the outside of the waveguide layer and the waveguide layer, The mode conversion means provided at the interface of the waveguide or the interface between the waveguide layer and the waveguide layer is composed of irregularities of the interface having regularity in a one-dimensional or two-dimensional direction. An electroluminescent light emitting device.

  Alternatively, in the fifth invention of the present application, the interface between the transparent substrate and the outside of the transparent substrate, the interface between the transparent substrate and the transparent electrode, the interface between the transparent electrode and the organic electroluminescence layer, the organic electroluminescence An interface between the sense layer and the metal electrode; an interface between the metal electrode and the outside of the metal electrode; an interface between the transparent substrate and the waveguide layer; an interface between the transparent electrode and the waveguide layer; The interface between the luminescence layer and the waveguide layer, the interface between the metal electrode and the waveguide layer, the interface between the waveguide layer and the outside of the waveguide layer, or the waveguide layer and the waveguide layer The organic electroluminescence light-emitting element is characterized in that the mode conversion means provided at the interface is configured by irregularities of the interface having regularity in a one-dimensional or two-dimensional direction.

  By providing irregularities with regularity in the one-dimensional or two-dimensional direction at the interface, a mode conversion means can be configured without providing materials with different refractive indexes, and an organic EL light emitting device with high light extraction efficiency can be easily obtained. Can be manufactured.

Another invention of the present application is the organic electroluminescence light-emitting element according to the fifth invention, wherein the organic EL layer has a light emission wavelength different depending on a region.
Even for organic EL light-emitting elements having different emission wavelengths depending on regions, an organic EL light-emitting element with high light extraction efficiency can be obtained by providing a mode conversion means.

According to another invention of the present application, in the above invention, the conversion means is an optical structure having a regular refractive index distribution in a one-dimensional, two-dimensional, or three-dimensional direction corresponding to the different emission wavelengths. It is an organic electroluminescence light emitting device characterized.
Mode conversion means can be provided in accordance with the emission wavelength of light emitted from the organic EL layer. For example, for an organic EL light emitting element that emits light in full colors of R, G, and B, an optimum mode conversion means can be provided for each emission color, and an organic EL light emitting element with high light extraction efficiency can be obtained.

  As described above, according to the present invention, it is possible to convert from the waveguide mode to the radiation mode using the mode conversion means, and the light extraction efficiency from the light emitting element such as the organic EL light emitting element can be improved. it can.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 4 shows an example of an optical structure having a regular refractive index distribution in a one-dimensional direction as a mode conversion means for converting the waveguide mode to the radiation mode. In FIG. 4, 22 is a waveguide mode, 23 is a radiation mode, 25 is an optical structure, and 41 is a mode conversion means. In FIG. 4, as the mode conversion means 41, the optical structure 25 is arranged in a one-dimensional direction (left and right directions in FIG. 4). Here, the refractive index of the optical structure 25 is set to be different from the refractive index of the material when the optical structure 25 is not provided.

  When the optical structure 25 is provided in such a period that the propagation of propagating light in the waveguide mode 22 is suppressed, the waveguide mode 22 is converted to the radiation mode 23 and emitted to the outside. . When such a mode conversion means is provided, the waveguide mode can be converted into the radiation mode in a one-dimensional direction.

  FIG. 5 shows an example of an optical structure having a regular refractive index distribution in a two-dimensional direction as a mode conversion means for converting the waveguide mode to the radiation mode. In FIG. 5, 22 is a waveguide mode, 23 is a radiation mode, 25 is an optical structure, and 41 is a mode conversion means. In FIG. 5, as the mode conversion means 41, the optical structure 25 is arranged in a two-dimensional direction (left and right directions and up and down directions in FIG. 5). Here, the refractive index of the optical structure 25 is set to be different from the refractive index of the material when the optical structure 25 is not provided.

  When the optical structure 25 is provided in such a period that the propagation of propagating light in the waveguide mode 22 is suppressed, the waveguide mode 22 is converted to the radiation mode 23 and emitted to the outside. . When such a mode conversion means is provided, the waveguide mode can be converted into the radiation mode in a two-dimensional direction.

  In FIG. 5, the optical structures 25 are arranged at the intersections on the two-dimensional matrix. However, as shown in FIG. 6, the optical structures described in FIG. 4 may be arranged in a two-dimensional matrix. Similar effects can be obtained. Furthermore, an optical structure having a regular refractive index distribution in a three-dimensional direction may be arranged. In this case, the optical structures may be arranged at the intersections on the three-dimensional matrix, or the optical structures may be arranged in a three-dimensional matrix. Placing optical structures in a three-dimensional direction allows for more complex designs. For example, the mode conversion function can be exhibited in a wider wavelength range.

  Next, an example of a refractive index distribution having regularity in a two-dimensional direction will be described. FIG. 7 shows an example in which an optical structure is arranged in a square lattice as mode conversion means. The optical structure may be arranged at the intersection of the dotted lines in FIG. 7, or the optical structure may be arranged at the position of the dotted line. When the periods in each direction are matched, the same wavelength characteristic is obtained in each direction. If the period is different in each direction, different wavelength characteristics are obtained in each direction.

  FIG. 8 shows an example in which an optical structure is arranged in a triangular lattice as mode conversion means. The optical structure may be arranged at the intersection of the dotted lines in FIG. 8, or the optical structure may be arranged at the position of the dotted line. When the periods in each direction are matched, the same wavelength characteristic is obtained in each direction. When the period is different in each direction, different wavelength characteristics can be obtained.

  FIG. 9 shows an example in which an optical structure is arranged in a honeycomb as mode conversion means. The optical structure may be arranged at the intersection of the dotted lines in FIG. 9, or the optical structure may be arranged at the position of the dotted line. When the periods in each direction are matched, the same wavelength characteristic is obtained in each direction. When the period is different in each direction, different wavelength characteristics can be obtained.

  FIG. 10 shows an example in which the plane is filled with a finite number of unit elements as mode conversion means. FIG. 10 shows one type of Penrose tile created by combining two types of similar triangles, and a plane can be filled with such a figure. With such an arrangement, it is possible to design wavelength characteristics in more directions.

  The mode conversion means having the structure described in FIGS. 4 to 10 is an example, and the present invention is not limited to such a structure.

  When the optical structure has a regular refractive index profile in one, two, or three dimensions, the regularity fluctuates with respect to the period of the effective wavelength of the light emitted from the organic EL layer. By providing the above, the light extraction efficiency from the organic EL light emitting element is improved. Even when the light emitted from the organic EL layer has a wavelength broadening, it is possible to effectively interfere with the light having a widened wavelength. Further, light from the organic EL light emitting element can be emitted not only in a specific direction but also in a wide angle, and directivity can be relaxed. The fluctuation is preferably equal to or less than ¼ of the period of the wavelength of light emitted from the organic EL layer. If the fluctuation is too great, the interference effect will decrease.

  The fluctuation described above may be mixed with a period of the effective wavelength of light emitted from the organic EL layer. By mixing fluctuations in the periodic regularity, it is possible to effectively interfere with light having a wavelength broadening emitted from the organic EL layer, and the light extraction efficiency of the organic EL light emitting element is improved. In addition, the directivity of light emitted from the organic EL light emitting element can be relaxed.

  Further, the regularity period may be gradually changed. This is a so-called chirping cycle. By gradually changing the period, it is possible to more effectively interfere with light having a wavelength broadening emitted from the organic EL layer, and the light extraction efficiency of the organic EL light emitting element is improved.

Next, an example of an organic EL light emitting element having an optical structure having a regular refractive index distribution as a mode conversion means will be described. In the description after FIG. 11, a transparent electrode, an organic EL layer, a metal electrode, and a transparent insulating film as the case may be are formed on the upper surface of the transparent substrate in order from the substrate side. In the case of a so-called top emission type organic EL light-emitting element in which light emitted from the organic EL layer is extracted from the side opposite to the substrate, an opaque substrate such as a Si substrate may be used instead of the transparent substrate. In the case of using a Si substrate, it is preferable that the SiO ₂ was oxidized surface on the side constituting the electrode. This is for insulation from the electrodes on the substrate. As an oxidation method, there is a method in which an oxygen atmosphere or water vapor is brought into contact with a Si substrate brought into a high temperature state to thermally oxidize the surface of the Si substrate. Since the top emission type organic EL light emitting element does not emit light from the transparent substrate, the extraction efficiency of light emitted from the organic EL layer is high. Further, when Si or SiO ₂ is used as the substrate, the heat dissipation effect is also high. Furthermore, even if an electronic circuit is mounted on the substrate, the extraction of light emitted from the organic EL layer is not affected.

  In the case of a top emission type organic EL light emitting element, in order to emit light emitted from the organic EL layer from the side opposite to the substrate, the metal electrode as the first electrode is used instead of the transparent electrode formed on the upper surface of the substrate. Also good. The metal electrode material is preferably a metal suitable for injecting and transporting carriers into the organic EL layer.

In the case of a top emission type organic EL light emitting device, the metal electrode formed on the upper surface of the organic EL layer may be replaced with a second electrode facing the first electrode. In the top emission type organic EL light emitting element, the light emitted from the organic EL layer is emitted from the second electrode side. Therefore, the second electrode is an electrode that is transparent to the light emitted from the organic EL layer. It is preferable that As the light-transmitting electrode, oxides such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), SnO ₂ (Tin Oxide), In ₂ O ₃ (Indium Oxide), and ZnO (Zinc Oxide) are used. Applicable. The second electrode may be a thin film metal electrode made of a metal such as Au or Ni. Alternatively, the second electrode may be an electrode in which a thin film metal electrode is disposed on the side of the organic EL layer of a light-transmitting electrode.

  FIG. 11 shows an example of an organic EL light-emitting element provided with mode conversion means inside a transparent substrate. FIGS. 12 to 14 show examples of an organic EL light-emitting element provided with mode conversion means at the interface between the transparent substrate and the outside of the transparent substrate. It is. 11 to 14, 31 is a metal electrode, 32 is an organic EL layer, 33 is a transparent electrode, 34 is a transparent substrate, and 41 is a mode conversion means. The transparent substrate includes a glass substrate, a flexible substrate, a substrate on which a color filter, a color conversion film, or a dielectric reflection film is formed. The transparent substrate can be made of glass, polyethylene terephthalate, polycarbonate, amorphous polyolefin, or the like.

  The mode conversion means 41 in FIG. 11 may have a regular refractive index distribution in a one-dimensional direction or may have a regular refractive index distribution in a two-dimensional or three-dimensional direction. The mode conversion means 41 in FIGS. 12 to 14 may have a regular refractive index distribution in a one-dimensional direction or may have a regular refractive index distribution in a two-dimensional direction. By providing mode conversion means inside the transparent substrate or at the interface between the transparent substrate and the outside of the transparent substrate, the transparent substrate waveguide mode is converted to the radiation mode, and the light emitted from the organic EL layer is transferred to the outside of the transparent substrate. It can be taken out efficiently.

  The mode conversion means 41 shown in FIG. 11 can be manufactured by forming the transparent substrate 34 by growing it twice and forming the mode conversion means in the middle, or by joining two transparent substrates. it can. The mode conversion means 41 shown in FIGS. 12 to 14 can form the mode conversion means 41 on one side of the transparent substrate 34 by etching or the like. By forming the transparent electrode 33, the organic EL layer 32, and the metal electrode 31 on the upper surface of these transparent substrates, an organic EL light emitting device can be manufactured. The organic EL light emitting device of the present invention is not limited to the manufacturing method described here.

FIG. 15 is an example of an organic EL light emitting device having a mode conversion means inside a transparent electrode, and FIGS. 16 to 18 are examples of an organic EL light emitting device having a mode conversion means at the interface between a transparent electrode and a transparent substrate. . 15 to 18, 31 is a metal electrode, 32 is an organic EL layer, 33 is a transparent electrode, 34 is a transparent substrate, and 41 is a mode conversion means. In order to use the transparent electrode as an anode (anode), a metal having a high work function and easy hole injection is suitable. Examples of materials that can be easily made transparent include oxides such as ITO (Indium Tin Oxide), IZO (indium zinc oxide), SnO ₂ (tin oxide), In ₂ O ₃ (indium oxide), and ZnO (zinc oxide). There are metals such as Au and Ni.

  The mode conversion means 41 in FIG. 15 may have a regular refractive index distribution in a one-dimensional direction or may have a regular refractive index distribution in a two-dimensional or three-dimensional direction. The mode conversion means 41 in FIGS. 16 to 18 may have a regular refractive index distribution in a one-dimensional direction or may have a regular refractive index distribution in a two-dimensional direction. By providing a mode conversion means inside the transparent electrode or at the interface between the transparent electrode and the transparent substrate, the transparent substrate waveguide mode or transparent electrode waveguide mode is converted into a radiation mode, and light emitted from the organic EL layer is transparent. It can be efficiently taken out of the substrate.

  The mode conversion means 41 shown in FIG. 15 can be manufactured by forming the transparent electrode 33 in a vapor deposition method, a sputtering method, or the like by growing it twice and forming the mode conversion means in the middle. . The mode conversion means 41 shown in FIGS. 16 to 18 forms the mode conversion means 41 on one side of the transparent substrate 34 by etching or the like, and then forms the transparent electrode 33, the organic EL layer 32, and the metal electrode 31 on the upper surface of the transparent substrate. An organic EL light emitting device can be manufactured by forming a film. The organic EL light emitting device of the present invention is not limited to the manufacturing method described here.

  FIG. 19 shows an example of an organic EL light emitting element having a mode conversion means inside the organic EL layer, and FIGS. 20 to 22 show examples of an organic EL light emitting element having a mode conversion means at the interface between the organic EL layer and the transparent electrode. It is. 19 to 22, 31 is a metal electrode, 32 is an organic EL layer, 33 is a transparent electrode, 34 is a transparent substrate, and 41 is a mode conversion means.

  The mode conversion means 41 in FIG. 19 may have a regular refractive index distribution in a one-dimensional direction or may have a regular refractive index distribution in a two-dimensional or three-dimensional direction. 20 to 22 may have a regular refractive index distribution in a one-dimensional direction or a regular refractive index distribution in a two-dimensional direction. Light emitted from the organic EL layer by converting the transparent electrode waveguide mode or the transparent substrate waveguide mode into a radiation mode by providing a mode conversion means inside the organic EL layer or at the interface between the organic EL layer and the transparent electrode. Can be efficiently taken out of the transparent substrate.

  The mode conversion means 41 shown in FIG. 19 forms the organic EL layer 32 in two portions when the organic EL layer 32 is formed by a spin coating method, a vacuum deposition method, coating, an ink jet method or the like. It can be manufactured by forming or the like. 20 to 22, after the mode conversion means 41 is formed on the surface of the transparent electrode 33 by etching or the like, the organic EL layer 32 and the metal electrode 31 are formed on the upper surface of the transparent electrode. Thus, an organic EL light emitting device can be manufactured. The organic EL light emitting device of the present invention is not limited to the manufacturing method described here.

  FIG. 23 shows an example of an organic EL light emitting element having a mode conversion means inside a metal electrode, and FIGS. 24 to 26 show examples of an organic EL light emitting element having a mode conversion means at the interface between the metal electrode and the organic EL layer. FIG. 27 to FIG. 29 are examples of organic EL light emitting elements provided with mode conversion means at the interface between the metal electrode and the outside of the metal electrode. 23 to 29, 31 is a metal electrode, 32 is an organic EL layer, 33 is a transparent electrode, 34 is a transparent substrate, and 41 is a mode conversion means. In order to use a metal electrode as a cathode, a metal having a low work function and easy electron injection is suitable. As the cathode electrode material, Al, Li, Mg, Au, Ag or the like or an alloy thereof can be used.

  The mode conversion means 41 in FIG. 23 may have a regular refractive index distribution in a one-dimensional direction or may have a regular refractive index distribution in a two-dimensional or three-dimensional direction. The mode conversion means 41 shown in FIGS. 24 to 29 may have a regular refractive index distribution in a one-dimensional direction or a regular refractive index distribution in a two-dimensional direction. As shown in FIGS. 24 and 25, by providing a mode conversion means at the interface between the organic EL layer and the metal electrode, the transparent electrode waveguide mode or the transparent substrate waveguide mode is converted into a radiation mode, and the organic EL layer The light emitted by can be efficiently extracted outside the transparent substrate.

  Here, if the metal electrode 31 is laminated to the same extent as the region where the evanescent wave exists or thinner than that, the inside of the metal electrode shown in FIGS. 23 to 29, the interface between the metal electrode and the organic EL layer, the metal electrode, By providing a mode conversion means at the interface with the outside of the metal electrode, the transparent electrode waveguide mode or the transparent substrate waveguide mode is converted into a radiation mode, and light emitted from the organic EL layer is efficiently transmitted to the outside of the transparent electrode. Can be taken out.

  Further, by making the metal electrode 31 into a thin layer, light emitted from the organic EL layer can be taken out from the metal electrode 31 side. Further, the metal electrode 31 is formed by providing a light-transmitting metal oxide such as ITO and a metal thin film such as Al or Li that is easy to inject electrons on the organic EL layer side of the metal oxide. Even with the structure, light can be extracted from the metal electrode 31 side. Further, when the metal electrode 31 is used as an anode, it is also possible to apply a light-transmitting metal oxide such as ITO. Therefore, the transparent electrode waveguide mode and the transparent substrate waveguide mode can be changed to the radiation mode by providing mode conversion means inside the metal electrode, at the interface between the metal electrode and the organic EL layer, and at the interface between the metal electrode and the outside of the metal electrode. The light emitted from the organic EL layer can be efficiently extracted outside the metal electrode. When taking out light emitted from the organic EL layer only from the metal electrode side, a substrate that does not transmit light emitted from the organic EL layer can be used instead of the transparent substrate described above.

  The mode conversion means 41 shown in FIG. 23 is manufactured by forming the metal electrode 31 in two steps when forming the film by vapor deposition or sputtering, and forming the mode conversion means in the middle. Can do. The mode conversion means 41 shown in FIG. 24 to FIG. 26 is formed by forming the mode conversion means 41 on the surface of the organic EL layer 32 by etching, and then forming a metal electrode 31 on the upper surface of the organic EL layer 32. A light emitting element can be manufactured. The mode conversion means 41 shown in FIGS. 27 to 29 can manufacture an organic EL light emitting element by forming the mode conversion means 41 on the upper surface of the metal electrode 31 by etching. The organic EL light emitting device of the present invention is not limited to the manufacturing method described here.

When the transparent substrate is made of glass, the mode conversion means in the glass can be made of rutile TiO ₂ , ZrO ₂ , chlorine-based polymer, or bromine-based polymer having a higher refractive index than glass. Chlorine polymers and bromine polymers are transmissive to light emitted from the organic EL layer, so that light transmission loss can be reduced. Further, the mode conversion means can be composed of nanoporous glass or a fluorine-based organic material having a refractive index lower than that of glass. Since these materials are transmissive to light emitted from the organic EL layer, light transmission loss can be reduced. Furthermore, when the mode conversion means is composed of gas, a material having a low refractive index can be obtained. As the gas, air or inert gas is preferable. The mode conversion means can be easily formed by forming bubbles with the atmospheric gas when producing the glass substrate in the atmosphere of air or inert gas.

When the transparent electrode is made of ITO, IZO, SnO ₂ , In ₂ O ₃ , ZnO or the like, the mode conversion means in the transparent electrode is made of rutile TiO ₂ or ZrO ₂ having a higher refractive index than the transparent electrode. can do. Further, the mode conversion means can be composed of nanoporous glass or a fluorine-based organic material having a refractive index lower than that of the transparent electrode. Since these materials are transmissive to light emitted from the organic EL layer, light transmission loss can be reduced. Furthermore, when the mode conversion means is composed of gas, a material having a low refractive index can be obtained. As the gas, air or inert gas is preferable. The mode conversion means can be easily formed by forming bubbles with the atmospheric gas when producing the transparent electrode in the atmosphere of air or inert gas.

When the organic EL layer is composed of PVK or Alq ₃ , the mode conversion means in the organic EL layer is made of rutile TiO ₂ , ZrO ₂ , chlorine-based polymer, bromine-based polymer having a higher refractive index than the organic EL layer. Can be configured. Chlorine polymers and bromine polymers are transmissive to light emitted from the organic EL layer, so that light transmission loss can be reduced. Further, the mode conversion means can be composed of nanoporous glass or a fluorine-based organic material having a refractive index lower than that of the organic EL layer. Since these materials are transmissive to light emitted from the organic EL layer, light transmission loss can be reduced. Furthermore, when the mode conversion means is composed of gas, a material having a low refractive index can be obtained. As the gas, air or inert gas is preferable. The mode conversion means can be easily formed by forming bubbles with the atmospheric gas when the organic EL layer is produced in the atmosphere of air or inert gas.

It is effective to form a transparent insulating film as a protective film on the outer side of the metal electrode layer in order to mechanically protect the metal electrode layer and the organic EL layer of the organic EL light emitting element and to prevent oxidation and moisture absorption. Examples of organic EL light emitting devices having a transparent insulating film are shown in FIGS. 30 to 36, 31 is a metal electrode, 32 is an organic EL layer, 33 is a transparent electrode, 34 is a transparent substrate, 35 is a transparent insulating film as a protective film, and 41 is a mode conversion means. The organic EL light emitting elements of FIGS. 30, 31, and 32 are obtained by forming a transparent insulating film 35 on the organic EL light emitting elements shown in FIGS. 27, 28, and 29, respectively. The metal electrode 31 or the organic EL layer 32 is protected. The formation of the transparent insulating film is not limited to these examples, and the metal electrode is protected by forming the transparent insulating film on the outside of the metal electrode of the organic EL light emitting element described above. These transparent insulating film _{SiO x, SiN x, SiON,} SiC, Al 2 O 3, AlN, ZnO, MgO x, TiO x, ZrO x, AlO x, Ta 2 O 5, TaO x, YO x, WO x Or the like as a material can be formed by sputtering, vapor deposition, vapor deposition polymerization, electron beam vapor deposition, plasma vapor deposition, ion plating, CVD, plasma CVD, thermal CVD, or the like. Moreover, it can also form by apply | coating an epoxy resin, an acrylic resin, a polyparaxylene, a fluorine-type polymer, a polyimide precursor, or spin-coating and ultraviolet-curing.

  When the transparent insulating film functions as a waveguide layer, mode conversion means can be provided inside the transparent insulating film or at the interface between the transparent insulating film and a layer adjacent to the transparent insulating film. 30, 31, and 32 each include a mode conversion means 41 at the interface between the metal electrode 31 and the transparent insulating film 35. The mode conversion means 41 may have a regular refractive index distribution in a one-dimensional direction or a regular refractive index distribution in a two-dimensional direction. The organic EL light emitting device of FIG. 33 includes mode conversion means 41 inside a transparent insulating film. This mode conversion means 41 may have a regular refractive index distribution in a one-dimensional direction or a regular refractive index distribution in a two-dimensional and three-dimensional direction.

  These mode conversion means may be formed not only at the positions shown in FIGS. 30 to 33 but also at the interface between the transparent insulating film and the outside. Each of the organic EL light emitting devices of FIGS. 34, 35, and 36 includes a mode conversion means 41 at the interface between the transparent insulating film 35 and the outside. The mode conversion means 41 may have a regular refractive index distribution in a one-dimensional direction or a regular refractive index distribution in a two-dimensional direction.

  In the organic EL light emitting device having a transparent insulating film, as shown in FIGS. 30 to 36, mode conversion means is provided at the interface between the metal electrode and the transparent insulating film, inside the transparent insulating film, and at the interface between the transparent insulating film and the outside. By providing, the waveguide mode in the transparent insulating film or in the waveguide layer including the transparent insulating film is converted into the radiation mode, and the light emitted from the organic EL layer is efficiently transmitted to the outside of the transparent insulating film or the transparent substrate. Can be taken out. In particular, in a so-called top emission type organic EL light emitting device, when a transparent electrode is used instead of a metal electrode, the emission efficiency is improved by providing a mode conversion means in the transparent insulating film and / or the transparent electrode. improves.

  The conversion from the waveguide mode to the radiation mode may be an organic EL element that further includes an optical function layer having a mode conversion means outside the metal electrode or the second electrode or outside the transparent insulating film as the protective layer. In particular, in the top emission type organic EL light emitting element, light emitted from the organic EL layer is emitted from the metal electrode, the second electrode, or the transparent insulating film side. By providing a mode conversion means inside the layer or at the interface of the optical functional layer, the light that has become the waveguide mode is also converted into a radiation mode and emitted to the outside of the organic EL light emitting element. An optical film can be applied as the optical functional layer. The optical film is also effective for preventing contact with the electrode and preventing physical damage to the organic EL light emitting device. The optical functional layer is not limited to an optical film, and any optical layer may be used as long as the waveguide layer is formed of a transparent material such as an optical film.

  Examples of a top emission type organic EL light emitting device having an optical film are shown in FIGS. 37 to 39, 41 is a mode conversion means, 44 is a substrate, 45 is a first electrode, 46 is an organic EL layer, 47 is a second electrode, 48 is a transparent insulating film as a protective film, and 49 is an optical film. is there. The organic EL light emitting device of FIG. 37 includes a mode conversion means 41 inside the optical film. Even if the mode conversion means has a regular refractive index distribution in a one-dimensional direction, it is two-dimensional or three-dimensional. It may have a regular refractive index distribution in the direction of. 38 and 39 are provided with mode conversion means 41 at the interface of the optical film. The mode conversion means has regularity in the two-dimensional direction even if it has a regular refractive index distribution in the one-dimensional direction. It may have a refractive index distribution. The organic EL light emitting device of FIG. 38 may be the organic EL light emitting device shown in FIGS. 34 to 36 provided with an optical film 49. The mode conversion means 41 formed at the interface between the optical film 49 and the outside in FIG. 39 may be on the optical film inner side, intermediate, or outer side of the interface.

  For the conversion from the waveguide mode to the radiation mode, an organic EL element that further includes an optical functional layer having a mode conversion means outside the substrate or the transparent substrate may be used. In particular, in a bottom emission type organic EL light emitting element, light emitted from the organic EL layer is emitted from the substrate or the transparent substrate side. Therefore, the inside of the optical functional layer, the inside of the optical functional layer, the optical functional layer, or the like. By providing a mode conversion means at the interface, light in the waveguide mode is also converted into a radiation mode and emitted to the outside of the organic EL light emitting element. An optical film can be applied as the optical functional layer. The optical film is also effective for preventing contact with the substrate or the transparent substrate and preventing physical damage to the organic EL light emitting device. The optical functional layer is not limited to an optical film, and any optical layer may be used as long as the waveguide layer is formed of a transparent material such as an optical film.

  Examples of bottom emission type organic EL light emitting devices having an optical film are shown in FIGS. 40 to 42, 31 is a metal electrode, 32 is an organic EL layer, 33 is a transparent electrode, 34 is a transparent substrate, 41 is a mode conversion means, 48 is a transparent insulating film as a protective film, and 49 is an optical film. . Whether or not to provide the transparent insulating film 48 is arbitrary. The organic EL light emitting device of FIG. 40 includes a mode conversion means 41 inside the optical film. Even if the mode conversion means has a regular refractive index distribution in a one-dimensional direction, it is two-dimensional or three-dimensional. It may have a regular refractive index distribution in the direction of. 41 and 42 are provided with mode conversion means 41 at the interface of the optical film. The mode conversion means has regularity in the two-dimensional direction even if it has a regular refractive index distribution in the one-dimensional direction. It may have a refractive index distribution. The mode conversion means 41 formed at the interface between the optical film 49 and the outside in FIG. 41 may be on the optical film inner side, intermediate, or outer side of the interface. The organic EL light emitting device of FIG. 42 may be the organic EL light emitting device shown in FIGS. 12 to 14 provided with an optical film 49.

  Such an optical film includes PMMA (Poly Methylmethacrylate), TAC (Triacetate), PVA (Polyvinyl Alcohol), PC (Polycarbonate), acrylic, polyethylene terephthalate, polyvinylene, traacetylcellulose, cycloolefin, UV curable resin, liquid crystalline Formed into an organic EL light emitting device by applying polymer or the like by spin coating, or by forming these materials into a sheet by biaxial stretching, casting, or extruding, and applying heat or adhesive. can do. The mode conversion means inside the optical film or at the interface can be formed by photolithography, soft lithography, UV imprinting, transfer method or the like.

  Soft lithography refers to a method of forming an etching pattern by pressing a resin-coated mold against an object. UV imprinting is a method of forming an etching pattern by pressing a mold coated with an ultraviolet curable resin against an object and then irradiating the ultraviolet ray to cure the ultraviolet curable resin.

  In the organic EL light emitting device having an optical film, as shown in FIG. 37 to FIG. 42, by providing a mode conversion means at the interface of the optical film or inside the optical film, the waveguide layer containing the optical film or in the optical film. By converting the waveguide mode in the above to the radiation mode, the light emitted from the organic EL layer can be efficiently extracted outside the optical film.

  Next, an example in which an optical structure having a regular refractive index distribution as a mode conversion means is constituted by irregularities of an interface having regularity in a one-dimensional or two-dimensional direction will be described with reference to FIGS. . 43 to 47, 31 is a metal electrode, 32 is an organic EL layer, 33 is a transparent electrode, 34 is a transparent substrate, and 41 is a mode conversion means. FIG. 43 shows an example in which the mode conversion means 41 is provided at the interface between the transparent substrate 34 and the outside of the transparent substrate 34. Such an optical structure is obtained by etching the transparent substrate 34, nanoimprinting, a transfer method, or the like. If the outside of the transparent substrate is air, the same effect can be obtained as when an optical structure having a regular refractive index distribution as a mode conversion means is formed of air. By providing a mode conversion means at the interface between the transparent substrate and the outside of the transparent substrate, the transparent substrate waveguide mode is converted into a radiation mode, and the light emitted from the organic EL layer is efficiently extracted to the outside of the transparent substrate. Can do.

  Nanoimprinting is a technique for impressing a mold having irregularities on a flat surface such as a substrate or a thin film, and if necessary, heating and pressing to imprint the irregularities of the mold on the substrate or thin film. In the case of using an ultraviolet curable resin for a substrate or a thin film, a method of irradiating with ultraviolet light, or a so-called soft lithography method in which a polymer is applied to a mold in advance is possible. The mold is preferably made of Si, SiC, Ni or the like having high mechanical strength.

  FIG. 44 shows an example in which mode conversion means is provided at the interface between the transparent electrode 33 and the transparent substrate 34. Such an optical structure can be obtained by forming a concavo-convex surface by performing etching, nanoimprinting, soft lithography, transfer, or the like on the transparent substrate 34, and then laminating the transparent electrode 33 on the concavo-convex surface. In general, the refractive index of the transparent electrode is higher than the refractive index of the transparent substrate, and there is a difference between the refractive indexes of the two, so that an optical structure having a regular refractive index distribution can be formed. By providing a mode conversion means at the interface between the transparent electrode and the transparent substrate, the transparent substrate waveguide mode or the transparent electrode waveguide mode is converted into a radiation mode, and light emitted from the organic EL layer is efficiently transmitted to the outside of the transparent substrate. Can be taken out.

  FIG. 45 shows an example in which mode conversion means is provided at the interface between the transparent electrode 33 and the organic EL layer 32. Such an optical structure is obtained by forming an uneven surface by etching, nanoimprinting, or transferring the transparent electrode 33, and then laminating the organic EL layer 32 on the uneven surface. In general, the refractive index of the transparent electrode is higher than the refractive index of the organic EL, and there is a difference between the refractive indexes of the two, so that an optical structure having a regular refractive index distribution can be formed. By providing a mode conversion means at the interface between the organic EL layer and the transparent electrode, the transparent electrode waveguide mode or the transparent substrate waveguide mode is converted into a radiation mode, and the light emitted from the organic EL layer is transferred to the outside of the transparent substrate. It can be taken out efficiently. In the case of a bottom emission type organic EL light emitting device, a mode conversion means is provided at the interface between the transparent electrode and the organic EL layer. Even in this case, the optical structure can be obtained by forming an uneven surface by performing etching or nanoimprinting on the transparent electrode, and then laminating an organic EL layer on the uneven surface.

  FIG. 46 shows an example in which mode conversion means is provided at the interface between the organic EL layer 32 and the metal electrode 31. When the metal electrode is laminated thicker than the region where the evanescent wave exists, the metal functions as a reflector. When unevenness is provided on the surface of such a reflector, an optical structure having a refractive index distribution can be formed. By providing a mode conversion means at the interface between the organic EL layer and the metal electrode, the transparent electrode waveguide mode or the transparent substrate waveguide mode is converted into a radiation mode, and the light emitted from the organic EL layer is transferred to the outside of the transparent substrate. It can be taken out efficiently.

  Further, by making the metal electrode 31 into a thin layer, light emitted from the organic EL layer 32 can be efficiently extracted from the side of the metal electrode 31 by mode conversion means provided at the interface between the organic EL layer and the metal electrode. it can. Furthermore, light can be efficiently emitted from the metal electrode 31 side by forming a laminated structure of a light-transmitting oxide such as ITO and a metal thin film such as Al or Li that has a low work function and facilitates electron injection. It can be taken out. Further, when a transparent electrode as the second electrode is used instead of the metal electrode, light can be efficiently extracted by the mode conversion means provided at the interface. Such unevenness can be obtained by forming an uneven surface by etching, nanoimprinting, soft lithography, or transferring the organic EL layer, and then laminating a metal electrode or a second electrode on the uneven surface.

  Therefore, by providing a mode conversion means at the interface between the metal electrode or the second electrode and the organic EL layer, the transparent electrode waveguide mode or the transparent substrate waveguide mode is converted into a radiation mode, and light emitted from the organic EL layer is emitted. Can be efficiently taken out of the metal electrode. When taking out light emitted from the organic EL layer only from the metal electrode side, a substrate that does not transmit light emitted from the organic EL layer can be used instead of the transparent substrate described above.

  FIG. 47 shows an example in which the mode conversion means is provided at the interface between the metal electrode 31 and the outside of the metal electrode 31. An optical structure having a refractive index distribution can be formed by laminating a metal electrode as thin as an area where an evanescent wave exists or thinner and performing etching, nanoimprinting, or transfer on the surface of the metal electrode 31. . With respect to such an optical structure, guided mode light oozes out from the organic EL layer 32 and functions as a mode conversion means. Therefore, by providing a mode conversion means at the interface between the metal electrode and the outside of the metal electrode, the transparent electrode waveguide mode or the transparent substrate waveguide mode is converted into a radiation mode, and the light emitted from the organic EL layer is converted into a transparent substrate. Can be taken out efficiently.

  Further, by making the metal electrode 31 into a thin layer, light emitted from the organic EL layer 32 can be extracted from the metal electrode 31 side. Furthermore, light can be extracted also from the side of the metal electrode 31 by forming a laminated structure of a light-transmitting oxide such as ITO and a metal thin film such as Al or Li with a low work function and easy electron injection. Can do. Further, when a transparent electrode as the second electrode is used instead of the metal electrode, light can be efficiently extracted by the mode conversion means provided at the interface.

  Therefore, by providing a mode conversion means at the interface between the metal electrode and the outside of the metal electrode, or at the interface between the second electrode and the outside of the second electrode, the transparent electrode waveguide mode or the transparent substrate waveguide mode is changed to the radiation mode. The light emitted from the organic EL layer after conversion can be efficiently extracted outside the metal electrode or the second electrode.

  45 to 47 also protects the metal electrode or the second electrode and the organic EL layer by forming a transparent insulating film as a protective film outside the metal electrode or the second electrode. can do. Further, in the organic EL light emitting device having a transparent insulating film outside the metal electrode or the second electrode, when the transparent insulating film functions as a waveguide layer, as shown in FIG. 48, the interface between the transparent insulating film and the outside A mode conversion means may be provided. In FIG. 48, 31 is a metal electrode, 32 is an organic EL layer, 33 is a transparent electrode, 34 is a transparent substrate, 35 is a transparent insulating film, and 41 is a mode conversion means. In an organic EL light-emitting device including a transparent insulating film outside the metal electrode or the second electrode, mode conversion means may be provided at the interface between the transparent insulating film and the outside. The optical structure having a regular refractive index distribution as the mode conversion means is composed of irregularities on the interface having regularity in a one-dimensional or two-dimensional direction. The irregularities on the regular interface can be formed by performing etching, nanoimprinting, soft lithography, or transfer on the surface of the transparent insulating film 35.

  By providing mode conversion means at the interface between the transparent insulating film and the outside, the waveguide mode in the transparent insulating film or in the waveguide layer including the transparent insulating film is converted into a radiation mode, and light is emitted from the organic EL layer. Light can be efficiently extracted outside the transparent insulating film or the transparent substrate.

  In a so-called top emission type organic EL light emitting device, an optical film as an optical functional layer may be provided outside the second electrode or the transparent insulating film in order to extract light from the side opposite to the substrate. Since the optical film can also be a waveguiding layer, it is preferable that the mode conversion means is constituted by irregularities of the interface having regularity in the one-dimensional or two-dimensional direction at the interface between the optical film and the outside of the optical film. FIG. 49 shows an example of an organic EL light emitting device in which regular irregularities are provided at the interface between the optical film and the outside of the optical film. In FIG. 49, 41 is a mode conversion means, 44 is a substrate, 45 is a first electrode, 46 is an organic EL layer, 47 is a second electrode, 48 is a transparent insulating layer as a protective film, and 49 is an optical film. In FIG. 49, whether or not to provide the transparent insulating film 48 is arbitrary.

  In the so-called top emission type organic EL light emitting device, in order to extract light from the side opposite to the substrate, an optical film as an optical functional layer is provided outside the second electrode or the transparent insulating film, and the optical film and the outside of the optical film are provided. By forming a mode conversion means with irregularities of the interface having regularity in the one-dimensional or two-dimensional direction at the interface, the waveguide mode is converted into a radiation mode, and the light emitted from the organic EL layer is converted into the optical film. It can be taken out efficiently.

  In so-called bottom emission type organic EL light emitting elements, an optical film as an optical functional layer may be provided outside the substrate in order to extract light from the substrate side. Since the optical film can also be a waveguiding layer, it is preferable that the mode conversion means is constituted by irregularities of the interface having regularity in the one-dimensional or two-dimensional direction at the interface between the optical film and the outside of the optical film. FIG. 50 shows an example of an organic EL light emitting device in which regular irregularities are provided at the interface between the optical film and the outside of the optical film. In FIG. 50, 41 is a mode conversion means, 34 is a transparent substrate, 33 is a transparent electrode, 32 is an organic EL layer, 31 is a metal electrode, and 49 is an optical film. In FIG. 50, whether or not to provide a transparent insulating film on the outside of the metal electrode 31 is arbitrary.

  In so-called bottom emission type organic EL light emitting devices, an optical film as an optical functional layer is provided outside the substrate in order to extract light from the substrate side, and one-dimensional or two-dimensional is provided at the interface between the optical film and the outside of the optical film. By forming the mode conversion means with the irregularities of the interface having regularity in the direction, it is possible to convert the waveguide mode to the radiation mode and efficiently extract the light emitted from the organic EL layer to the outside of the optical film it can.

  The organic EL light emitting element may be provided with two or more mode conversion means by combining the mode conversion means shown in FIGS. The two or more mode conversion means may be optical structures having different regularities. By selecting the optimal structure for the mode conversion from the guided mode to the radiation mode in each layer, or by efficiently converting the mode from the guided mode to the radiation mode in cooperation with optical structures with different periods, The light extraction efficiency of the organic EL light emitting device is more efficiently improved.

  If irregularities are formed as a result of providing irregularities at the interface between the substrate and the first electrode or forming a refractive index distribution with different materials, the irregularities may be transferred to the layer formed on the upper surface. An example in which unevenness is transferred is shown in FIG. In FIG. 51, 42 is the mode conversion means provided at the interface between the substrate and the first electrode, 44 is the substrate, 45 is the first electrode, 46 is the organic EL layer, 47 is the second electrode, 48 is the transparent insulating film, 49 Is an optical film. Unevenness is formed on the upper surface of the substrate 44 by etching, nanoimprinting, or transfer. When the first electrode 45 is laminated on the upper surface on which the unevenness is formed, the unevenness at the interface between the substrate 44 and the first electrode 45 may be transferred to the interface between the first electrode 45 and the organic EL layer 46 in some cases. . When the first electrode 45 is thin, it is transferred when the first electrode is laminated along the unevenness of the lower surface.

  This transfer may extend not only to the interface between the first electrode 45 and the organic EL layer 46 but also to a layer formed on the upper portion thereof. Further, not only the unevenness provided at the interface between the substrate and the first electrode, but also the unevenness provided in the other layers or at the interface may reach the layer formed on the upper surface thereof. Such unevenness becomes an optical structure having a regular refractive index distribution in a one-dimensional or two-dimensional direction. However, the period of each layer is the same. If the refractive index is different for each layer, the effective wavelength is different for each layer, which is equivalent to having a period with fluctuations for each layer. For this reason, even if the wavelength of the light emitted from the organic EL layer is broadened, the light extraction efficiency of the organic EL light emitting element is improved. In addition, the directivity of light extracted from the organic EL light emitting element can be relaxed.

  If the surface of the substrate and the optical film as the optical functional layer is uneven, or if the surface is uneven as a result of forming a refractive index distribution with different materials, the unevenness may be transferred to the outer interface of the optical film. is there. An example in which the unevenness is transferred is shown in FIG. 52, 31 is a metal electrode, 32 is an organic EL layer, 33 is a transparent electrode, 34 is a transparent substrate, 42 is a mode conversion means provided at the interface between the transparent substrate and the optical film, and 49 is an optical film. Unevenness is formed on the outer surface of the transparent substrate 34 by etching, nanoimprinting, or transfer. When the optical film is formed on the upper surface on which the unevenness is formed, the unevenness at the interface between the transparent substrate 34 and the optical film 49 may be transferred to the interface between the optical film 49 and the outside of the optical film 49 in some cases. When the optical film 49 is thin, it is transferred when the optical film is formed along the unevenness of the transparent substrate.

  Not only the unevenness provided at the interface between the transparent substrate and the optical film, but also the unevenness provided in the inside of other layers or at the interface may reach the optical film. Such unevenness becomes an optical structure having a regular refractive index distribution in a one-dimensional or two-dimensional direction. However, the period of each layer is the same. If the refractive index is different for each layer, the effective wavelength is different for each layer, which is equivalent to having a period with fluctuations for each layer. For this reason, even if the wavelength of the light emitted from the organic EL layer is broadened, the light extraction efficiency of the organic EL light emitting element is improved. In addition, the directivity of light extracted from the organic EL light emitting element can be relaxed.

  Two or more mode conversion means may be provided in the same layer. FIG. 53 is a perspective view of an organic EL light emitting device having two or more mode exchange means as seen from a direction perpendicular to the light emitting surface. 54 is a cross-sectional view taken along line A-A ′ in FIG. 53. 53 and 54, reference numerals 51 and 52 denote mode conversion means. In FIG. 53 and FIG. 54, other elements of the organic EL light emitting element are omitted. In FIG. 53 and FIG. 54, a tetragonal lattice with different intervals is used in the first stage and the second stage. For example, the vertical and horizontal directions of the first stage may be effective wavelengths, and the second stage may be effective wavelengths in an oblique direction. The structure may be not only a tetragonal lattice but also a trigonal lattice or a hexagonal lattice as described above. Moreover, it is good also as a different shape in the 1st step and the 2nd step.

  In FIGS. 53 and 54, a laminated structure is used, but mode conversion means having different periods may be provided so as to overlap on the same plane. By providing two or more mode conversion means in the same layer, the organic EL light-emitting device can be more efficiently converted by efficiently performing mode conversion from the waveguide mode to the radiation mode in cooperation with optical structures having different periods. The light extraction efficiency is improved, and the directivity in the extraction direction is reduced.

  FIG. 55 shows the propagation characteristics of the waveguide mode when an optical structure having a regular refractive index distribution is formed as the mode conversion means. In FIG. 55, the horizontal axis represents the wavelength, and the vertical axis represents the propagation loss of the waveguide mode with respect to the wavelength. When the period of the refractive index distribution is about the effective wavelength of light, it has the property of suppressing the propagation of light having a specific wavelength. At a wavelength at which propagation is suppressed, since the waveguide mode is converted to the radiation mode, propagation loss increases at a specific wavelength as shown in FIG. However, in an actual light emitting element, since the emission wavelength has a wavelength broadening, it is necessary to widen the wavelength range in which propagation is suppressed.

  For example, in addition to the regular period, the wavelength range in which the propagation is suppressed is widened by providing fluctuations of ¼ or less of the period. If the wavelength whose propagation is suppressed is set to the wavelength characteristic as shown in FIG. 56 in accordance with the emission wavelength of the light emitting element, the waveguide mode is set to the radiation mode for the emitted light even if the light emitting element has a broad wavelength. Can be converted to In addition, the directivity of the light extraction direction from the organic EL light emitting element can be reduced.

  The same effect can be obtained even if a regular cycle and fluctuations of ¼ or less of the cycle are mixed. Further, the same effect can be obtained even if the rule is such that the period gradually changes.

  When the organic EL light emitting element is applied to a color display, the organic EL layer is formed with a material corresponding to the wavelength to emit light. FIG. 57 shows a configuration of a picture element of a general full color display. In FIG. 57, a picture element in which regions emitting light of R, G, and B are alternately arranged emits light, whereby a full color display is possible. In such a full-color organic EL light emitting device, the mode conversion means may have an optical structure having a common regular refractive index distribution without distinguishing between R, G, and B. In this case, it is not necessary to change the structure of the mode conversion means for each of R, G, and B.

  On the other hand, a structure having a regular refractive index distribution corresponding to the emission wavelength for each of the R, G, and B emission regions may be used. In this case, each light emitting region has a period corresponding to the wavelength of the emitted light. Since the period is different for each light emitting region, the structure of the refractive index distribution is complicated, but the structure optimal for the wavelength of light emission can be obtained.

Next, the manufacturing method of the organic EL light emitting device of the present invention will be described. Here, the mode conversion means is formed by nanoimprinting on the surface of the substrate or / and the organic EL layer. First, mode conversion means is formed on the surface of the substrate by nanoimprinting. When the substrate is a glass substrate, a mold formed of Si or SiC is heated and pressed against the glass substrate. The heating temperature is, for example, 150 ° C. when the material is a polymer and 350 ° C. when the material is glass. Pressing force, for example, if the material is a polymer 1.5 N / mm ^2, in the case of glass which is 2.5 N / mm ^2.

  After forming irregularities as mode conversion means on the substrate surface, the substrate is washed to remove unnecessary contamination. When Si is used as the substrate, at least the surface on which the organic EL light emitting element is formed is oxidized with thermal steam. ITO or a metal to be an electrode is laminated on the substrate by sputtering. The layer thickness of the ITO or electrode metal is 100 to 150 nm. A resist film is formed by spin coating in order to pattern ITO or metal. As a material for the resist film, PMMA can be applied in the case of electron beam lithography described later. The film thickness is 0.3-1 μm. Photolithography or electron beam lithography can be applied to form the etching pattern. After forming the etching pattern, ITO or metal is finished into an electrode pattern by etching. For the etching, dielectric coupling type plasma etching is preferable. After the etching, the resist is removed. An oxygen plasma removal method or a solution removal method can be applied to the resist removal.

  An organic EL layer is formed on the top surface of the ITO electrode or metal electrode. The organic EL layer is laminated with a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer as necessary.

  As materials for the hole injection layer and the hole transport layer, Pentacene, Tetracene, Anthracene, Phthalocyanine, α-Sexithiophene, α, ω-Diethylenthiophene, Oligopheneylene, Oligophenylene, Oligophenylene -Hexylthiophene), Poly (3-butylthiophene), Poly (phenylenevinylene, Poly (thienylenevinylene), Polyacetylene, α, ω-Dihexyl-quinquethione, PD, α PD, m-MTDATA, it TPAC, TCTA, Polyvinylcarbozole, PDA, CuPc, STB, MTDATA, PEDOT-PSS, be exemplified a TPDPES-TBPAH.

Electron injection layer, the material of the electron transport _{layer, C 6 -PTC, C 8 -PTC} , C 12 -PTC, C 13 -PTC, Bu-PTC, F 7 Bu-PTC *, Ph-PTC, F 5 Ph -PTC *, can _PTCBI, PTCDI, TCNQ, _{C 60} fullerene, BCP, Alq3, PBD, OXD , TAZ, TPOB, ZnPBO, BCP, OXD-7, Bphen, be exemplified a phenanthroline derivative such as ZnPBO.

As a method for laminating the organic EL layer, there are a spin coating method, a vacuum deposition method, a coating method, and an ink jet method. The stack thickness is 5 nm to 3000 nm. Nanoimprinting is suitable when mode conversion means is formed on the surface of the organic EL layer. The organic EL layer is heated and pressed. The heating temperature may be room temperature. The pressing force is, for example, 200 N / mm ² .

  A metal electrode or ITO electrode is formed on the upper surface of the organic EL layer. The formation method is almost the same as the formation method of the ITO electrode or metal electrode formed on the substrate.

If necessary, a transparent insulating film as a protective film is laminated. These transparent insulating film _{SiO x, SiN x, SiON,} SiC, Al 2 O 3, AlN, ZnO, MgO x, TiO x, ZrO x, AlO x, Ta 2 O 5, TaO x, YO x, WO x Or the like as a material can be formed by sputtering, vapor deposition, vapor deposition polymerization, electron beam vapor deposition, plasma vapor deposition, ion plating, CVD, plasma CVD, thermal CVD, or the like. Moreover, it can also form by apply | coating an epoxy resin, an acrylic resin, a polyparaxylene, a fluorine-type polymer, a polyimide precursor, or spin-coating and ultraviolet-curing.

  When forming an optical film as an optical functional element on the surface of the organic EL light emitting element, PMMA (Poly Methylmethacrylate), TAC (Triacetate), PVA (Polyvinyl Alcohol), PC (Polycarbonate), acrylic, polyethylene terephthalate, polyvinylene, Applying or spin-coating traacetylcellulose, cycloolefin, UV curable resin, liquid crystalline polymer, etc., or bi-axially stretching, casting, or extruding these materials and sticking them together by heating or sticking It can be formed into an organic EL light emitting element by attaching an agent. The mode conversion means inside the optical film or at the interface can be formed by photolithography, soft lithography, transfer method or the like.

  The organic EL light emitting device of the present invention can be applied to an organic EL light emitting device. Moreover, the light emitting element of the present invention can be widely applied to not only an organic EL light emitting device but also a flat display device.

It is a figure showing the electric field distribution of the transparent electrode waveguide mode confined by the transparent electrode. It is a figure explaining the technique which provided the condensing lens in the boundary of the transparent electrode and transparent substrate which is a prior art. It is a figure explaining the basic principle of this invention. It is a figure explaining the example of the optical structure which has a refractive index distribution with regularity in a one-dimensional direction. It is a figure explaining the example of the optical structure which has a refractive index distribution with regularity in a two-dimensional direction. It is a figure explaining the example of the optical structure which has a regular refractive index distribution in the two-dimensional direction arrange | positioned at matrix form. It is a figure explaining the example which arranged the square lattice of the optical structure as a mode conversion means. It is a figure explaining the example which arranged the triangular structure of the optical structure as a mode conversion means. It is a figure explaining the example which arrange | positioned the optical structure as a mode conversion means as a honeycomb. It is a figure explaining the example made into the arrangement | positioning which can fill a plane with a finite number of unit elements as a mode conversion means. It is a figure explaining the example of the organic electroluminescent light emitting element provided with the mode conversion means inside the transparent substrate. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent substrate and the exterior of a transparent substrate. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent substrate and the exterior of a transparent substrate. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent substrate and the exterior of a transparent substrate. It is a figure explaining the example of the organic electroluminescent light emitting element which provided the mode conversion means inside the transparent electrode. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent electrode and a transparent substrate. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent electrode and a transparent substrate. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent electrode and a transparent substrate. It is a figure explaining the example of an organic EL light emitting element provided with a mode conversion means inside an organic EL layer. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of an organic electroluminescent layer and a transparent electrode. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of an organic electroluminescent layer and a transparent electrode. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of an organic electroluminescent layer and a transparent electrode. It is a figure explaining the example of an organic electroluminescent light emitting element provided with a mode conversion means inside a metal electrode. It is a figure explaining the example of an organic EL light emitting element provided with the mode conversion means in the interface of a metal electrode and an organic EL layer. It is a figure explaining the example of an organic EL light emitting element provided with the mode conversion means in the interface of a metal electrode and an organic EL layer. It is a figure explaining the example of an organic EL light emitting element provided with the mode conversion means in the interface of a metal electrode and an organic EL layer. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a metal electrode and the exterior of a metal electrode. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a metal electrode and the exterior of a metal electrode. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a metal electrode and the exterior of a metal electrode. It is a figure explaining the example of an organic EL light emitting element provided with the mode conversion means in the interface of a metal electrode and a transparent insulating film. It is a figure explaining the example of an organic EL light emitting element provided with the mode conversion means in the interface of a metal electrode and a transparent insulating film. It is a figure explaining the example of an organic EL light emitting element provided with the mode conversion means in the interface of a metal electrode and a transparent insulating film. It is a figure explaining the example of an organic electroluminescent light emitting element provided with a mode conversion means inside a transparent insulating film. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent insulating film and the exterior of a transparent insulating film. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent insulating film and the exterior of a transparent insulating film. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent insulating film and the exterior of a transparent insulating film. It is a figure explaining the example of an organic electroluminescent light emitting element which equips the inside of an optical film with a mode conversion means. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of an optical film and a transparent insulating film. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of an optical film and the exterior of an optical film. It is a figure explaining the example of an organic electroluminescent light emitting element which equips the inside of an optical film with a mode conversion means. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of an optical film and the exterior of an optical film. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of an optical film and a transparent substrate. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent substrate and the exterior of a transparent substrate. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent electrode and a transparent substrate. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent electrode and an organic electroluminescent layer. It is a figure explaining the example of an organic EL light emitting element provided with the mode conversion means in the interface of an organic EL layer and a metal electrode. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a metal electrode and the exterior of a metal electrode. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent insulating film and the exterior of a transparent insulating film. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of an optical film and the exterior of an optical film. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of an optical film and the exterior of an optical film. It is a figure explaining the example of an organic electroluminescent element provided with the mode conversion means in the interface of a board | substrate and a 1st electrode. It is a figure explaining the example of an organic electroluminescent light emitting element provided with the mode conversion means in the interface of a transparent substrate and an optical film. It is a top view explaining the example of an organic electroluminescent light emitting element provided with a two-stage mode conversion means. It is sectional drawing explaining the example of an organic electroluminescent light emitting element provided with a two-stage mode conversion means. It is a figure explaining the propagation characteristic of a waveguide mode when an optical structure with a regular refractive index distribution is formed as mode conversion means. It is a figure explaining the propagation characteristic of the waveguide mode which extended the wavelength from which propagation is suppressed. It is a figure explaining the picture element of a full color display.

Explanation of symbols

22 waveguide mode 23 radiation mode 25 optical structure 31 metal electrode 32 organic EL layer 33 transparent electrode 34 transparent substrate 35 transparent insulating film 41 mode conversion means 44 substrate,
45 first electrode,
46 organic EL layer,
47 Second electrode,
48 transparent insulation layer,
49 Optical film 81 Glass substrate 82 Transparent electrode 83 Organic EL layer 84 Condensing lens

Claims (28)

An organic electroluminescence light-emitting device comprising, in order, at least a first electrode, an organic electroluminescence layer, and a second electrode facing the first electrode on a substrate, the interior of the substrate The inside of the first electrode, the inside of the organic electroluminescent layer, the inside of the second electrode, the interface between the substrate and the outside of the substrate, the interface between the substrate and the first electrode, Of the interface between the first electrode and the organic electroluminescent layer, the interface between the organic electroluminescent layer and the second electrode, or the interface between the second electrode and the outside of the second electrode Comprising at least one mode conversion means for converting the waveguide mode to the radiation mode;
The mode conversion means is an optical structure having a refractive index distribution having a regularity of a period of about the effective wavelength of light emitted from the organic electroluminescence layer in a one-dimensional, two-dimensional, or three-dimensional direction. The
The regularity has a fluctuation of ¼ or less of a period with respect to a period of an effective wavelength of light emitted from the organic electroluminescence layer,
The mode converting means has at least two or more optical structures having a regular refractive index distribution in a two-dimensional direction, and the regularity of the optical structures is within the range of the fluctuation for each optical structure. An organic electroluminescence light-emitting element characterized by having different periods . 2. The organic electroluminescence according to claim 1 , wherein the second electrode is a transparent electrode, a thin film metal electrode, or an electrode in which a thin film metal is disposed on the transparent electrode and the organic electroluminescence layer side of the transparent electrode. Sense light emitting element. 2. The organic electroluminescent layer according to claim 1 , further comprising an optical functional layer provided with a mode conversion unit that converts a waveguide mode into a radiation mode on the outer surface of the substrate or the outer surface of the second electrode. Sense light emitting element. On the substrate, at least a first electrode, an organic electroluminescence layer, and a second electrode facing the first electrode are sequentially provided, and one or more of any one on the substrate An organic electroluminescence light-emitting device having a waveguide layer, wherein the interior of the substrate, the interior of the first electrode, the interior of the organic electroluminescence layer, the interior of the second electrode, the interior of the waveguide layer Inside, interface between the substrate and the outside of the substrate, interface between the substrate and the first electrode, interface between the first electrode and the organic electroluminescent layer, the organic electroluminescent layer and the first An interface between two electrodes, an interface between the second electrode and the outside of the second electrode, an interface between the substrate and the waveguide layer, an interface between the first electrode and the waveguide layer, An interface between the organic electroluminescent layer and the waveguide layer, an interface between the second electrode and the waveguide layer, Interface with an external waveguide layer and the conductor-wave layer, or in at least one of the interface between the conductor-wave layer and the conductor waveguide layer provided with a mode conversion means for converting the waveguide mode to the radiation mode,
The mode conversion means is an optical structure having a refractive index distribution having a regularity of a period of about the effective wavelength of light emitted from the organic electroluminescence layer in a one-dimensional, two-dimensional, or three-dimensional direction. The
The regularity has a fluctuation of ¼ or less of a period with respect to a period of an effective wavelength of light emitted from the organic electroluminescence layer,
The mode converting means has at least two or more optical structures having a regular refractive index distribution in a two-dimensional direction, and the regularity of the optical structures is within the range of the fluctuation for each optical structure. An organic electroluminescence light-emitting element characterized by having different periods . 5. The organic electroluminescence according to claim 4 , wherein the second electrode is a transparent electrode, a thin film metal electrode, or an electrode in which a thin film metal is disposed on the transparent electrode and the organic electroluminescence layer side of the transparent electrode. Sense light emitting element. Organic electroluminescence light-emitting device having at least a first electrode, an organic electroluminescence layer, a light-transmissive second electrode facing the first electrode, and a protective film in this order on the substrate An element comprising: the interior of the substrate; the interior of the first electrode; the interior of the organic electroluminescent layer; the interior of the second electrode; the interior of the protective film; and the exterior of the substrate and the substrate. An interface; an interface between the substrate and the first electrode; an interface between the first electrode and the organic electroluminescent layer; an interface between the organic electroluminescent layer and the second electrode; A mode conversion means for converting from a waveguide mode to a radiation mode at least one of an interface between the electrode and the protective film or an interface between the protective film and the outside of the protective film;
The mode conversion means is an optical structure having a refractive index distribution having a regularity of a period of about the effective wavelength of light emitted from the organic electroluminescence layer in a one-dimensional, two-dimensional, or three-dimensional direction. The
The regularity has a fluctuation of ¼ or less of a period with respect to a period of an effective wavelength of light emitted from the organic electroluminescence layer,
The mode converting means has at least two or more optical structures having a regular refractive index distribution in a two-dimensional direction, and the regularity of the optical structures is within the range of the fluctuation for each optical structure. An organic electroluminescence light-emitting element characterized by having different periods . The organic electroluminescence light emitting device according to claim 6 , further comprising an optical functional layer provided with a mode conversion means for converting from a waveguide mode to a radiation mode on the outer surface of the substrate or the outer surface of the protective film. element. On the substrate, at least a first electrode, an organic electroluminescence layer, a second electrode that is transparent to the first electrode, and a protective film, and a protective film in this order, and An organic electroluminescence light-emitting device having one or more waveguide layers on any of the substrates, the interior of the substrate, the interior of the first electrode, the interior of the organic electroluminescence layer, the second The inside of the electrode, the inside of the protective film, the inside of the waveguide layer, the interface between the substrate and the outside of the substrate, the interface between the substrate and the first electrode, the first electrode and the organic electroluminescence An interface with the sense layer, an interface between the organic electroluminescent layer and the second electrode, an interface between the second electrode and the protective film, an interface between the protective film and the outside of the protective film, the substrate And the waveguide layer, the interface between the first electrode and the waveguide layer, the organic electroluminescence An interface between the second layer and the waveguide layer, an interface between the second electrode and the waveguide layer, an interface between the protective film and the waveguide layer, and an outside of the waveguide layer and the waveguide layer. Mode conversion means for converting the waveguide mode to the radiation mode at least one of the interface or the interface between the waveguide layer and the waveguide layer;
The mode conversion means is an optical structure having a refractive index distribution having a regularity of a period of about the effective wavelength of light emitted from the organic electroluminescence layer in a one-dimensional, two-dimensional, or three-dimensional direction. The
The regularity has a fluctuation of ¼ or less of a period with respect to a period of an effective wavelength of light emitted from the organic electroluminescence layer,
The mode converting means has at least two or more optical structures having a regular refractive index distribution in a two-dimensional direction, and the regularity of the optical structures is within the range of the fluctuation for each optical structure. An organic electroluminescence light-emitting element characterized by having different periods . An organic electroluminescence light-emitting device comprising, in order, at least a transparent electrode, an organic electroluminescence layer, and a metal electrode facing the transparent electrode on a transparent substrate, the inside of the transparent substrate, the transparent electrode The inside of the organic electroluminescent layer, the inside of the metal electrode, the interface between the transparent substrate and the outside of the transparent substrate, the interface between the transparent substrate and the transparent electrode, the transparent electrode and the organic electroluminescence Mode conversion means for converting from a waveguide mode to a radiation mode at least one of an interface with a sense layer, an interface between the organic electroluminescence layer and the metal electrode, or an interface between the metal electrode and the outside of the metal electrode With
The mode conversion means is an optical structure having a refractive index distribution having a regularity of a period of about the effective wavelength of light emitted from the organic electroluminescence layer in a one-dimensional, two-dimensional, or three-dimensional direction. The
The regularity has a fluctuation of ¼ or less of a period with respect to a period of an effective wavelength of light emitted from the organic electroluminescence layer,
The mode converting means has at least two or more optical structures having a regular refractive index distribution in a two-dimensional direction, and the regularity of the optical structures is within the range of the fluctuation for each optical structure. An organic electroluminescence light-emitting element characterized by having different periods . 10. The organic electroluminescence according to claim 9 , further comprising an optical functional layer provided with mode conversion means for converting from a waveguide mode to a radiation mode on an outer surface of the transparent substrate or an outer surface of the metal electrode. Light emitting element. On the transparent substrate, at least a transparent electrode, an organic electroluminescent layer, and a metal electrode facing the transparent electrode are sequentially provided, and one or more waveguide layers are provided on any of the transparent substrates. An organic electroluminescent light emitting device comprising: the inside of the transparent substrate, the inside of the transparent electrode, the inside of the organic electroluminescent layer, the inside of the metal electrode, the inside of the waveguide layer, the transparent substrate and the The interface with the outside of the transparent substrate, the interface between the transparent substrate and the transparent electrode, the interface between the transparent electrode and the organic electroluminescent layer, the interface between the organic electroluminescent layer and the metal electrode, the metal electrode And an interface between the transparent electrode and the waveguide layer, an interface between the transparent electrode and the waveguide layer, an interface between the organic electroluminescent layer and the waveguide layer, The boundary between the metal electrode and the waveguide layer , A mode conversion means for converting the waveguide mode to the radiation mode on at least one of the interface with the interface, or the electrically-wave layer and the conductor-wave layer between the external conductor-wave layer and the conductor-wave layer,
The mode conversion means is an optical structure having a refractive index distribution having a regularity of a period of about the effective wavelength of light emitted from the organic electroluminescence layer in a one-dimensional, two-dimensional, or three-dimensional direction. The
The regularity has a fluctuation of ¼ or less of a period with respect to a period of an effective wavelength of light emitted from the organic electroluminescence layer,
The mode converting means has at least two or more optical structures having a regular refractive index distribution in a two-dimensional direction, and the regularity of the optical structures is within the range of the fluctuation for each optical structure. An organic electroluminescence light-emitting element characterized by having different periods . The interface between the substrate and the outside of the substrate, the interface between the substrate and the first electrode, the interface between the first electrode and the organic electroluminescence layer, the organic electroluminescence layer and the second The optical structure provided at the interface with the electrode or the interface between the second electrode and the outside of the second electrode is configured by irregularities of the interface having regularity in a one-dimensional or two-dimensional direction. The organic electroluminescent light-emitting device according to claim 1, 2, 3, 6 or 7 . The interface between the substrate and the outside of the substrate, the interface between the substrate and the first electrode, the interface between the first electrode and the organic electroluminescence layer, the organic electroluminescence layer and the second An interface between the electrode, an interface between the second electrode and the outside of the second electrode, an interface between the substrate and the waveguide layer, an interface between the first electrode and the waveguide layer, the organic electro The interface between the luminescence layer and the waveguide layer, the interface between the second electrode and the waveguide layer, the interface between the waveguide layer and the outside of the waveguide layer, or the waveguide layer and the waveguide 9. The organic electroluminescence according to claim 4, 5 or 8 , wherein the optical structure provided at the interface with the layer is composed of irregularities of the interface having regularity in a one-dimensional or two-dimensional direction. Sense light emitting element. The interface between the transparent substrate and the outside of the transparent substrate, the interface between the transparent substrate and the transparent electrode, the interface between the transparent electrode and the organic electroluminescent layer, the organic electroluminescent layer and the metal electrode The optical structure provided at an interface or an interface between the metal electrode and the outside of the metal electrode is configured by irregularities of an interface having regularity in a one-dimensional or two-dimensional direction. The organic electroluminescent light-emitting device according to 9 or 10 . The interface between the transparent substrate and the outside of the transparent substrate, the interface between the transparent substrate and the transparent electrode, the interface between the transparent electrode and the organic electroluminescent layer, the organic electroluminescent layer and the metal electrode An interface, an interface between the metal electrode and the outside of the metal electrode, an interface between the transparent substrate and the waveguide layer, an interface between the transparent electrode and the waveguide layer, the organic electroluminescence layer and the waveguide layer The optical structure provided at the interface between the metal electrode and the waveguide layer, the interface between the waveguide layer and the outside of the waveguide layer, or the interface between the waveguide layer and the waveguide layer The organic electroluminescent light-emitting device according to claim 11 , wherein the organic electroluminescence light-emitting device is configured by irregularities of an interface having regularity in a one-dimensional or two-dimensional direction. The organic electroluminescent light emitting element is provided with two or more mode conversion means, organic according to any one of claims 1 to 15, regularity of the two or more mode conversion means, characterized in that the same period Electroluminescence light emitting device. The organic electroluminescent light-emitting device according to claim 1, wherein the two or more optical structures are formed in the same two-dimensional plane. The regularity is characterized in that a period of about an effective wavelength of light emitted from the organic electroluminescence layer and a fluctuation of a quarter or less of the period with respect to a period of the effective wavelength are mixed. The organic electroluminescent light emitting element according to any one of claims 1 to 17 . The organic electroluminescent device as claimed in any of claims 1 to 18, wherein the regularity of the period gradually changes. The refractive index distribution having regularity in the two-dimensional direction is a square lattice arrangement, a triangular lattice arrangement, a honeycomb lattice arrangement, an arrangement that can fill a plane with a finite number of unit elements, or a combination thereof. The organic electroluminescent light-emitting device according to any one of claims 1 to 19 , The organic material according to any one of claims 1 to 20 , wherein the regular refractive index distribution is formed of a material having a refractive index higher than that of a material in a case where the regular refractive index distribution is not provided. Electroluminescence light emitting device. The organic electroluminescence light-emitting element according to claim 21 , wherein the material having a high refractive index has transparency to light emitted from the organic electroluminescence layer. The organic material according to any one of claims 1 to 20 , wherein the regular refractive index distribution is formed of a material having a refractive index lower than that of a material in a case where the regular refractive index distribution is not provided. Electroluminescence light emitting device. The organic electroluminescent light-emitting element according to claim 23 , wherein the material having a low refractive index is transparent to light emitted from the organic electroluminescent layer. The organic electroluminescent light-emitting element according to claim 23 , wherein the material having a low refractive index is a gas. The organic electroluminescent light-emitting element according to claim 25 , wherein the gas is air or an inert gas. The organic electroluminescent device as claimed in any of claims 1 26, wherein the organic electroluminescent layer and having an emission wavelength different from the region. The mode converting means has an optical structure having a regular refractive index distribution in a one-dimensional, two-dimensional, or three-dimensional direction corresponding to the different emission wavelength for each of the regions having the different emission wavelengths. The organic electroluminescent light-emitting device according to claim 27 .

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