JP2011228229A - Organic electroluminescent device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic EL device, in particular, a top emission-type organic EL device, having further increased light extraction efficiency and high-definition.SOLUTION: In an organic electroluminescent device, an organic electroluminescent element 21 in which a function layer 12 including at least an organic light-emitting layer is provided between an anode 10 and a cathode 11 is formed over an element substrate 20. Both of the anode 10 and the cathode 11 are formed so as to have light transmission property. A reflection layer 15 including a concave 15a is provided on a base layer 16 of the anode 10 that is provided at the opposite side of the cathode 11 so as to be directed toward the anode 10.

Description

  The present invention relates to an organic electroluminescence device.

  An organic electroluminescence element (organic EL element) is a self-luminous light-emitting element, and has a property that it emits light in all directions when emitted. Therefore, by extracting light that diverges in all directions in one direction, which is the observation surface, it is possible to improve the light extraction efficiency and improve the luminance and the life of the material.

  Therefore, conventionally, in order to provide the direction of light extraction, a reflective layer is formed on the side opposite to the observation surface with respect to the organic EL element, and light that diverges on the side opposite to the observation surface is extracted from the observation surface side. A structure is employed (see, for example, Patent Document 1).

JP 2003-332067 A

  However, in an organic EL display in which a large number of organic EL elements are formed, light emitted in an oblique direction without going straight from the organic EL element side toward the observation surface side is different from the corresponding unit pixel area (for example, adjacent to the pixel area). May be taken out through the unit pixel area. Then, the contrast is lowered. In particular, in the case of full-color display in which a color filter is provided in the unit pixel region, light emitted in an oblique direction passes through a color filter of a different color next to it, so that a color different from the original display is displayed. Display will be made.

  As countermeasures, conventionally, the black matrix on the counter substrate side that is the observation surface side is expanded, the aperture ratio of the organic EL element is reduced, and the gap between the organic EL element and the counter substrate is narrowed. ing. However, in recent years, there has been a demand for higher definition in organic EL displays. Therefore, if the black matrix is expanded or the aperture ratio of the organic EL element is reduced, the luminance of the organic EL display is lowered, which becomes a factor that hinders high definition, which is not preferable. Further, if the gap between the organic EL element and the counter substrate is made further narrower than the current state, the manufacturing process becomes difficult and the productivity is lowered.

  The above-mentioned Patent Document 1 discloses a so-called bottom emission type light emitting panel that emits light from an element substrate side on which an organic EL element is formed, but emits light from a counter substrate side facing the element substrate. Also in the so-called top emission type organic EL device, it is desired to further improve the light extraction efficiency.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an organic EL device that can increase the light extraction efficiency and achieve high definition, particularly in a top emission type organic EL device. There is to do.

The organic electroluminescence device of the present invention is an organic electroluminescence device comprising an element substrate formed with an organic electroluminescence element having a functional layer including at least an organic light emitting layer between an anode and a cathode,
The anode and the cathode are both formed with translucency,
The base layer provided on the opposite side of the anode from the anode is provided with a reflective layer having a concave surface.

  According to this organic electroluminescent device, since the reflective layer having a concave surface is provided on the anode underlayer, light is emitted from the functional layer, and the light transmitted through the translucent anode and directed toward the underlayer is reflected. The light is reflected by the layer and passes through the light-transmitting cathode and is emitted to the observation surface side. At this time, since the reflective layer has a concave surface, the light reflected by the reflective layer is condensed and emitted to a predetermined region of the observation surface, for example, a corresponding unit pixel region. Therefore, particularly in a top emission type device, the light extraction efficiency can be further increased, and thereby high definition can be achieved.

Further, in the organic electroluminescence device, the element substrate is provided with a plurality of organic electroluminescence elements, and a counter substrate in which a unit pixel region corresponding to the organic electroluminescence element is formed on the cathode side of the element substrate. A reflection surface disposed between the unit pixel regions, the light-shielding layer being provided between the unit pixel regions, and facing the reflection layer of the organic electroluminescence element corresponding to the unit pixel region adjacent to the light-shielding layer on the cathode side of the light-shielding layer It is preferable that the reflective convex part which has is provided.
In this way, a part of the light emitted to the counter substrate side proceeds in an oblique direction without going straight toward the corresponding unit pixel region, and is reflected by the reflecting surface of the reflecting convex portion toward the light shielding layer. Reflected towards the layer. Accordingly, when the light is further reflected by the reflective layer, the reflected light is emitted through the corresponding unit pixel region, and the light extraction efficiency is further increased.

In addition, it is preferable that the reflective surface of the said reflective convex part is a concave surface.
In this way, the light reflected from the reflecting surface is more reliably directed to the reflecting layer, and thus the light extraction efficiency is further increased.

Further, in the organic electroluminescence device, the element substrate is provided with a plurality of organic electroluminescence elements, and a counter substrate in which a unit pixel region corresponding to the organic electroluminescence element is formed on the cathode side of the element substrate. Preferably, a reflector having a reflective surface facing the reflective layer of the organic electroluminescence element corresponding to each adjacent unit pixel region is provided on the cathode side between the unit pixel regions. .
In this way, a part of the light emitted to the counter substrate side proceeds in an oblique direction without going straight toward the corresponding unit pixel region, and also between the unit pixel regions, due to the reflecting surface of the reflector. Reflected toward the reflective layer. Accordingly, when the light is further reflected by the reflective layer, the reflected light is emitted through the corresponding unit pixel region, and the light extraction efficiency is further increased.

In addition, it is preferable that the reflective surface of the said reflector is a concave surface.
In this way, the light reflected from the reflecting surface is more reliably directed to the reflecting layer, and thus the light extraction efficiency is further increased.

In the organic electroluminescence device, a color filter may be provided in the unit pixel region.
In this way, the light emitted from each organic electroluminescence element passes through the corresponding unit pixel region more reliably, so that it passes through the different unit pixel region, and thus passes through the color filters of different colors. As a result, display of a color different from the original display is prevented.

Moreover, in the said organic electroluminescent apparatus, it is preferable that the said base layer consists of a planarization layer.
By doing so, since the underlayer is a flattened layer without unevenness, the organic electroluminescence element formed thereon can be formed with a uniform thickness. Therefore, variation in thickness between organic electroluminescence elements can be suppressed, and luminance can be made uniform between elements.

In the organic electroluminescence device, it is preferable that the anode is located inside the reflective layer without coming out of the reflective layer in a plan view.
In this way, the light that passes through the anode in the oblique direction and passes through the outside of the anode and is emitted to the base layer side is also reflected by the reflective layer and travels toward the corresponding unit pixel region.

1 is a side sectional view showing a schematic configuration of a first embodiment of an organic EL device of the present invention. It is a sectional side view which shows typically the principal part of 1st Embodiment of an organic EL apparatus. (A)-(e) is manufacturing-process explanatory drawing of the organic electroluminescent apparatus shown in FIG. It is a sectional side view which shows typically the principal part of 2nd Embodiment of an organic electroluminescent apparatus. It is a sectional side view which shows typically the principal part of 3rd Embodiment of an organic electroluminescent apparatus. It is a perspective view which shows the mobile phone as an application example of an organic EL apparatus.

Embodiments of the present invention will be described below with reference to the drawings. In each figure, the scale is different for each member in order to make each member recognizable on the drawing.
FIG. 1 is a side sectional view showing a schematic configuration of a first embodiment of an organic EL device (organic electroluminescence device) according to the present invention, and reference numeral 1 in FIG. 1 denotes an organic EL device. The organic EL device 1 is a so-called “top emission type” organic EL device.

  The organic EL device 1 includes an element substrate 20 on which a plurality of organic EL elements 21 are arranged, and an electrode protective layer 17, an organic buffer layer 18, and a gas barrier layer 19 that are formed to cover the plurality of organic EL elements 21. Each layer is provided with a counter substrate 30 disposed to face the surface of the element substrate 20 on which the plurality of organic EL elements 21 are disposed. The element substrate 20 and the counter substrate 30 are bonded to each other through a sealing material 33 and an adhesive layer 34.

  The organic EL element 21 generates light of a single emission color, and has a functional layer 12 that generates white light in this example. On the element substrate 20, the plurality of organic EL elements 21 are regularly arranged in a matrix to form a display region L. Note that a region corresponding to the outside of the display region L is a non-display region M.

  The element substrate 20 includes an element substrate body 20a and an inorganic insulating layer 14 that covers the surface of the element substrate body 20a on the counter substrate 30 side. As the element substrate body 20a, either a transparent substrate or an opaque substrate can be used. Examples of opaque substrates include ceramics such as alumina, metal sheets such as stainless steel that have been subjected to insulation treatment such as surface oxidation, thermosetting resins and thermoplastic resins, and films thereof (plastic films). It is done. As the transparent substrate, for example, an inorganic substance such as glass, quartz glass, or silicon nitride, or an organic polymer (resin) such as an acrylic resin or a polycarbonate resin can be used. In addition, a composite material formed by laminating or mixing the above materials can also be used as long as it has optical transparency. In this example, glass is used as the material of the element substrate body 20a.

A plurality of thin film transistors (TFTs) 123 and various wirings (not shown) corresponding to the plurality of organic EL elements 21 on a one-to-one basis are formed on the element substrate main body 20a. Layer 14 is formed. The inorganic insulating layer 14 is formed of a silicon compound such as silicon oxide (SiO ₂ ) or silicon nitride (SiN).

  A planarizing layer 16 is formed on the element substrate 20 to alleviate surface irregularities derived from wirings, TFT elements and the like provided in the element substrate 20. The planarizing layer 16 is formed of an insulating resin material, such as a photosensitive acrylic resin or cyclic olefin resin, and serves as a base layer provided on the side opposite to the cathode with respect to the anode described later. ing.

In addition, in the planarization layer 16, the organic EL element 21 emits light, and the light directed toward the flat lower layer 16, which is the underlying layer, is reflected toward the counter substrate 30 without reflecting toward the counter substrate 30. Layer 15 is formed.
As shown in FIG. 2 schematically showing the display region L, the reflective layer 15 is formed with a concave surface 15a facing the organic EL element 21, and a reflective metal is formed on the concave surface 15a. The film 15b is provided and formed. The metal film 15b is made of Al (aluminum), which is the same as the wiring material, in order to serve as a wiring and a manufacturing process. Further, in addition to Al, for example, it may be formed of a metal such as Ti (titanium), Mo (molybdenum), Ag (silver), Cu (copper), or an alloy material combining them.

On the planarizing layer 16, the anode 10 of the organic EL element 21 is formed in a region overlapping the reflective layer 15 in plan view. As shown in FIG. 1, the anode 10 is connected to the TFT 123 on the element substrate body 20a through a contact hole (not shown) penetrating the planarization layer 16 and the inorganic insulating layer. Moreover, the anode 10 has translucency, and a material having a high hole injection effect having a work function of 5 eV or more is preferably used. Examples of such a material having a high hole injection effect include ITO (Indium Tin Oxide), zinc-doped indium oxide, indium oxide (In ₂ O ₃ ), tin oxide (SnO ₂ ), and zinc oxide ( Metal oxides such as ZnO). In this example, ITO is used.

  An insulating partition layer 13 that partitions the organic EL element 21 is formed on the planarization layer 16. The partition layer 13 includes a plurality of openings that expose the upper portion of the anode 10. The partition wall layer 13 is formed of an insulating resin material similarly to the planarization layer 16, and for example, a photosensitive acrylic resin or a cyclic olefin resin is used as the material.

  A functional layer 12 is formed so as to cover the upper surface of the partition layer 13 and the anode 10 along the uneven shape formed by the opening and the partition layer 13. The functional layer 12 includes an organic light emitting layer that emits light when excited by recombination of holes and electrons injected by an electric field, and further includes a multilayer film including layers other than the organic light emitting layer. As a layer other than the organic light emitting layer, a hole injection layer for facilitating injection of holes, a hole transport layer for facilitating transport of injected holes to the light emitting layer, and facilitating injection of electrons There are layers that contribute to the above-described recombination, such as an electron injection layer for the purpose and an electron transport layer for facilitating transport of the injected electrons to the light emitting layer. The electron injection layer is formed of a material having a large electron injection effect (work function is 4 eV or less) such as Ca.

  The organic light emitting layer of the functional layer 12 is formed from a low molecular organic EL material or a high molecular organic EL material. The low molecular weight organic EL material has a relatively low molecular weight among organic compounds that emit light by being excited by recombination of holes and electrons. The high molecular weight organic EL material has a relatively high molecular weight among organic compounds that emit light when excited by recombination of holes and electrons. The low molecular weight organic EL material or the high molecular weight organic EL material forming the organic EL element 21 is a substance corresponding to light of a single color emitted from the organic EL element 21 (white light). The material of the layer contributing to recombination in the light emitting layer is a substance corresponding to the material of the layer in contact with this layer.

  On the functional layer 12, the functional layer 12 is covered so as to follow the uneven shape of the functional layer 12 and extends to the side wall portion of the planarizing layer 16 disposed on the outermost periphery (side closer to the outer peripheral portion of the element substrate 20). Thus, a light-transmitting cathode 11 is formed. As the cathode 11, a thin film made of a material having a large electron injection effect (a work function of 4 eV or less) is preferably used. The cathode 11 includes, for example, an electron injection buffer layer for facilitating injection of electrons into the functional layer 12 and a layer with low electrical resistance formed from a metal such as ITO or Al on the electron injection buffer layer. Is done. The electron injection buffer layer is made of, for example, LiF (lithium fluoride), Ca (calcium), or MgAg (magnesium-silver alloy).

  A cathode wiring 22 is formed on the element substrate 20 in a region where the planarizing layer 16 is not formed near the outer periphery of the element substrate 20 in the non-display region M. The cathode wiring 22 and the cathode 11 are electrically connected.

  The cathode wiring 22 is formed for the purpose of energizing the cathode 11 to a power source (not shown), and is mainly provided near the outer periphery of the element substrate 20. As a material for forming the cathode wiring 22, a metal such as aluminum, titanium, molybdenum, tantalum, silver, or copper having high electrical conductivity or an alloy thereof is used, and these materials are laminated in a single layer or multiple layers. What was formed is used. In this example, three layers of titanium, aluminum, and titanium are used. In addition, ITO, which is the same material as the anode 10, is formed on the outermost layer of the cathode wiring 22.

  An electrode protective layer 17 is formed on the element substrate 20 so as to cover the inorganic insulating layer 14, the planarization layer 16, and the cathode 11 of the organic EL element 21. The electrode protective layer 17 is made of, for example, a silicon compound such as silicon oxynitride (SiON).

  An organic buffer layer 18 is formed on the electrode protective layer 17 so as to cover the electrode protective layer 17. The organic buffer layer 18 is formed so as to fill the uneven shape formed by the partition wall layer 13 and the opening thereof, and the element substrate 20 is planarized. As a material for forming the organic buffer layer 18, for example, an epoxy compound can be used.

  A gas barrier layer 19 is formed on the organic buffer layer 18 so as to cover the organic buffer layer 18 and further to the terminal portion of the electrode protective layer 17. The gas barrier layer 19 is made of, for example, SiON in consideration of translucency, gas barrier properties, and water resistance.

  The electrode protective layer 17 and the gas barrier layer 19 are formed so as to cover a part of the cathode wiring 22. As described above, ITO (oxide conductive film) used for the anode 10 is formed on the surface of the cathode wiring 22. The gas barrier layer 19 is formed wider than the organic buffer layer 18 so as to completely cover the organic buffer layer 18, and the sealing material 33 is disposed on the gas barrier layer 19.

  On the surface side of the element substrate 20 on which the gas barrier layer 19 is formed, that is, on the cathode 11 side, a counter substrate 30 is disposed facing the element substrate 20. The counter substrate 30 is bonded to the gas barrier layer 19 on the element substrate 20 through the adhesive layer 34 and the sealing material 33. The counter substrate 30 includes a counter substrate body 31 made of a light transmissive (translucent) material such as glass or transparent plastic.

  A plurality of sub-pixel regions (unit pixel regions) 35 respectively corresponding to the plurality of organic EL elements 21 are formed in the counter substrate body 31 as shown in FIG. In these sub-pixel regions 35, a red color layer (color filter) 37 R, a green color layer (color filter) 37 G, and a blue color layer (color filter layer 37) are formed on the surface (inner surface) facing the element substrate 20. Color filters) 37B are regularly arranged in a matrix. One pixel is formed by the three sub-pixel regions 35 in which the red colored layer 37R, the green colored layer 37G, and the blue colored layer 37B are respectively formed. Further, the display region L is formed by having a large number of such pixels vertically and horizontally.

  A black matrix layer (light-shielding layer) 32 is formed between the adjacent sub-pixel regions 35 so as to surround the colored layer 37R (37G, 37B). The black matrix layer (light shielding layer) 32 is formed in a region facing the partition wall layer 13 of the element substrate 20 and is formed of a light shielding material such as Cr (chromium).

  The colored layers 37R, 37G, and 37B are arranged so as to face the white light emitting functional layer 12 formed on the anode 10 and overlap in a plan view. Thereby, the white light emitted from the functional layer 12 passes (transmits) through each of the colored layers 37R, 37G, and 37B, and is emitted to the observer side as each color light of red light, green light, and blue light. It has become.

Further, an overcoat layer (planarization layer) 38 is formed on the inner surface side of the counter substrate body 31 so as to cover the color filter layer 37 and the black matrix layer 32 formed in the display region L. The overcoat layer 38 extends from the inside of the display area L to the formation area of the sealing material 33 in the non-display area M. The overcoat layer 38 is formed of, for example, a resin material such as acrylic or polyimide, or a light-transmitting inorganic insulating material such as SiO ₂ .
A gas barrier layer 39 that covers the overcoat layer 38 is formed on the overcoat layer 38. The gas barrier layer 39 is made of, for example, SiON in consideration of translucency, gas barrier properties, and water resistance.

  A sealing material 33 is formed on the outer peripheral portion between the element substrate 20 and the counter substrate 30. As a material for forming the sealing material 33, for example, a material having a low moisture-permeable resin structure in which silica, alumina or the like is added as a filler to an epoxy resin can be used. Note that a gap agent (not shown) made of, for example, resin or glass is disposed inside the sealing material 33. In addition, as the sealing material 33, it is good also as a structure which does not contain a gap agent.

  In manufacturing the organic EL device 1 having such a structure, in order to form the reflective layer 15 in particular, first, as shown in FIG. And made of acrylic resin or the like. In FIG. 3A, the description of the inorganic insulating film 14 is omitted.

  Next, as shown in FIG. 3B, a resist pattern 51 having an opening 50 in the formation region of the organic EL element 21 is formed on the planarization layer 16. Subsequently, a substantially spherical recess is formed in the opening 50 by, for example, wet etching using the resist pattern 51. Thereby, the concave surface 15a of the spherical inner surface exposed in the concave portion is formed. For the formation of the recess (concave surface 15a), in addition to wet etching, nanoimprint using a pressing mold having a convex negative pattern, dry etching using a resist pattern, or the like can be employed.

Subsequently, as shown in FIG. 3C, Al as a reflective metal material is formed on the entire surface of the planarizing layer 16 by sputtering or the like. Thereby, a metal film 15b made of Al is formed on the concave surface 15a. The formation of the metal film 15b is preferably performed in the same process as the wiring (not shown) manufacturing process as described above.
Next, as shown in FIG. 3D, the resist pattern 51 is removed, thereby removing the metal film 15b on the resist pattern 51, thereby selectively leaving the metal film 15b only on the concave surface 15a. However, when a wiring (not shown) is simultaneously formed by the metal film 15b, it is a matter of course that this wiring is also left as it is.

  Thereafter, as indicated by a solid line in FIG. 3E, a light-transmitting material such as an acrylic resin is embedded in the recess and cured, and the surface thereof is flush with the surface of the planarizing layer 16. Thereby, the reflective layer 15 which consists of the concave surface 15a and the metal film 15b which covers this in the planarization layer 16 is formed. Further, as shown by a two-dot chain line in FIG. 3E, a translucent material is disposed so as to fill the recess and cover the surface of the planarizing layer 16, and further planarize the entire surface to newly A flattened layer 16a may be formed. Even when the planarization layer 16a is formed in this way, the reflection layer 15 composed of the concave surface 15a and the metal film 15b is obtained.

  After forming the reflective layer 15 and the planarizing layer 16 (16a) in this way, the anode 10 is formed immediately above the reflective layer 15 in the same manner as in the prior art. Furthermore, the functional layer 12 and the cathode 11 are formed so as to cover the anode 10 and the partition wall layer 13, and the organic EL element 21 is formed.

  In forming the reflective layer 15, as shown in FIG. 3 (e), the inside of the concave portion is not buried, and therefore the planarizing layer 16 is left without being flattened again. The organic EL element 21 may be directly formed thereon. However, when the organic EL element 21 is directly formed on the concave portion (on the reflective layer 15), the anode 10, the functional layer 12, and the cathode 11 constituting the organic EL element 21 also have a curved shape following the shape of the concave surface 15a. It becomes difficult to form each of them with a uniform thickness, and as a result, there is a risk that variations in luminance occur between a large number of organic EL elements 21. On the other hand, as shown in FIG. 3 (e), the recesses are filled or the planarization layer 16 is planarized again, whereby the underlying layer of the organic EL element 21 is made a substantial planarization layer, If the EL elements 21 are formed, variations in thickness between the organic EL elements 21 can be suppressed, and the luminance can be made uniform among the elements 21.

In the organic EL device 1 of this embodiment provided with such a reflective layer 15, the reflective layer 15 having the concave surface 15 a is formed on the planarizing layer 16 that is the base layer of the anode 10. As shown in the figure, light emitted from the functional layer 12, transmitted through the light-transmitting anode 10 and directed toward the base layer (planarization layer 16) is reflected by the reflection layer 15, and passes through the light-transmitting cathode 11. Then, the light is emitted to the counter substrate 30 side which is the observation surface side. At this time, since the reflective layer 15 has the concave surface 15a, the light reflected by the reflective layer 15 is a predetermined region of the observation surface, that is, each colored layer 37R, 37G, sub-pixel region (unit pixel region) 35. The light is condensed on 37 </ b> B and emitted to the outside of the counter substrate 30. Accordingly, the reflected light is taken out through another (for example, the adjacent) sub-pixel region 35 (colored layer), so that the contrast is lowered or a color different from the original display is displayed. Inconvenience is prevented.
Therefore, according to the organic EL device 1 of the present embodiment, it is possible to increase the light extraction efficiency, particularly in a top emission type device, thereby achieving high definition.

Next, a second embodiment of the organic EL device of the present invention will be described.
FIG. 4 is a diagram schematically showing the display region L of FIG. 1 and is a diagram for explaining a schematic configuration of the organic EL device of the second embodiment.
The organic EL device shown in FIG. 4 is different from the organic EL device 1 shown in FIGS. 1 and 2 in that the organic EL device shown in FIG. 4 has a reflective protrusion on the black matrix layer (light-shielding layer) 32. 60 is provided.

  That is, in the organic EL device 1 according to the first embodiment, by providing the reflective layer 15 having the concave surface 15a, the light transmitted through the anode 10 toward the base layer (planarization layer 16) is transmitted to the subpixel region. The light is condensed on each colored layer 37R (37) in the (unit pixel region) 35, but the light that goes directly from the organic EL element 21 to the counter substrate 30 side is one as shown by the dashed arrow in FIG. The portion is directed toward the black matrix layer 32. Then, since this light is absorbed by the black matrix layer 32, the spectral extraction efficiency decreases.

  Therefore, in the present embodiment, as shown in FIG. 4, the reflective convex portion 60 is provided on the black matrix layer (light-shielding layer) 32 so that the light directed toward the black matrix layer 32 is reflected by the reflective convex portion 60. In this case, the light is returned to the reflective layer 15 at the corresponding position and is reflected again by the reflective layer 15 so as to be emitted toward the colored layers 37R (37) of the sub-pixel region (unit pixel region) 35. is there.

The reflective protrusion 60 may be formed directly on the black matrix layer 32, but may be formed on the overcoat layer 38 shown in FIG. 1, and further formed on the gas barrier layer 39. It may be. In the present embodiment, it is assumed that it is formed on an overcoat layer 38 (not shown in FIG. 4) made of an inorganic material (for example, SiO ₂ ).

  In addition, the reflective convex portion 60 faces the reflective layer 15 located immediately below the organic EL element 21 corresponding to each of the sub-pixel regions 35 and 35 adjacent to the black matrix layer (light shielding layer) 32 provided with the reflective convex portion 60. It is formed as follows. In other words, the reflective convex portion 60 is located on the side of the sub-pixel region 35R adjacent to one side of the black matrix layer (light-shielding layer) 32 provided with the reflective convex portion 60, directly below the organic EL element 21R corresponding to the sub-pixel region 35R. A reflective surface 60a facing the reflective layer 15R is formed on the side of the sub-pixel region 35G adjacent to the other side, and the reflective layer 15G located immediately below the organic EL element 21G corresponding to the sub-pixel region 35G is formed. A reflective surface 60b facing is formed.

The boundary between the reflecting surfaces 60a and 60b is, for example, on the center line (bisector) of the black matrix layer 32. Moreover, these reflective surfaces 60a and 60b are concave surfaces in this embodiment, and the light reflected here can be favorably condensed by the corresponding reflective layer 15.
Moreover, the reflective convex part 60 is formed by the base part (not shown) which consists of acrylic resins, for example, and the reflective film provided in the outer surface. That is, it is formed by forming a base portion having a concave reflecting surface shape with acrylic resin or the like, and further forming a reflective material such as Al on the outer surface thereof.

  In forming such a reflective convex portion 60, the colored layers 37R, 37G, and 37B and the black matrix layer 32 are formed on the counter substrate body 31, and the overcoat layer 38 is further formed thereon. For example, an acrylic resin is disposed on the coat layer 38. Subsequently, a base having a desired concave shape to be a reflective surface is formed by dry etching (or wet etching) using a resist pattern or nanoimprint. Thereafter, a reflective material such as Al is selectively formed on the surface to be a reflective surface by using, for example, a resist pattern. Thereby, the reflective convex part 60 is obtained.

  In addition, after forming the overcoat layer 38 which consists of inorganic materials on each colored layer 37R, 37G, 37B, since the reflective convex part 60 is formed on this overcoat layer 38, with this overcoat layer 38, each It is prevented that the colored layers 37R, 37G, and 37B are damaged in the process.

  In the organic EL device in which such a reflective convex portion 60 is formed, a part of the light emitted from the organic EL element 21 to the counter substrate 30 side is directed to the corresponding sub-pixel region 35. Thus, the light travels in an oblique direction without going straight, and can be reflected toward the corresponding reflective layer 15 by the reflective surface 60a (60b) of the reflective convex portion 60 even toward the black matrix layer 32. Therefore, by further reflecting on the reflective layer 15, the reflected light can be emitted from the corresponding sub-pixel region 35, and the light extraction efficiency can be further enhanced.

  Moreover, since the reflective surfaces 60a and 60b of the reflective convex portion 60 are concave surfaces that can be condensed on the corresponding reflective layer 15, the light reflected by these reflective surfaces 60a and 60b is respectively reflected by the corresponding reflective layer 15. The light can be reflected and condensed well, and the light extraction efficiency can be further increased.

Next, a third embodiment of the organic EL device of the present invention will be described.
FIG. 5 is a diagram schematically illustrating the display region L of FIG. 1 and is a diagram for explaining a schematic configuration of the organic EL device of the third embodiment.
The organic EL device shown in FIG. 5 differs from the organic EL device shown in FIG. 4 in that the black EL matrix layer (light shielding layer) 32 is not formed on the counter substrate 30 in the organic EL device shown in FIG. In other words, a reflector 65 is provided directly or indirectly between adjacent sub-pixel regions (unit pixel regions) 35 and 35.

  That is, the reflector 65 may be formed directly on the counter substrate body 31, but may be formed on the overcoat layer 38 shown in FIG. 1, and further formed on the gas barrier layer 39. It may be. In the present embodiment, it is assumed that an overcoat layer 38 (not shown in FIG. 5) made of an inorganic material is formed and then formed on the overcoat layer 38.

  Similar to the reflective convex portion 60 shown in FIG. 4, the reflector 65 is formed on the reflective layer 15 located immediately below the organic EL element 21 corresponding to each of the sub-pixel regions 35 and 35 adjacent to the position where the reflective convex portion 60 is provided. It is formed to face. In other words, the reflector 65 is located on the side of the sub-pixel region 35R adjacent to one side between the sub-pixel regions 35 and 35 provided with the reflector 65, immediately below the organic EL element 21R corresponding to the sub-pixel region 35R. A reflective surface 65a facing the reflective layer 15R is formed, and on the side of the sub-pixel region 35G adjacent to the other side, a reflective surface facing the reflective layer 15G located immediately below the organic EL element 21G corresponding to the sub-pixel region 35G. 65b is formed.

The boundary between these reflecting surfaces 65a and 65b is, for example, on the center line (bisector) between the sub-pixel regions 35 and 35 provided with the reflecting surfaces 65a and 65b. Moreover, these reflective surfaces 65a and 65b are also concave surfaces in this embodiment, and the light reflected here can be favorably condensed by the corresponding reflective layer 15.
The reflector 65 is made of a reflective metal such as Al. Or similarly to the said reflective convex part 60, you may form by the base part (not shown) which consists of acrylic resins, for example, and the reflective film provided in the outer surface.

  When such a reflector 65 is formed of a reflective metal such as Al, the colored layers 37R, 37G, and 37B are formed on the counter substrate main body 31, and are further covered on the counter substrate main body 31. After the overcoat layer 38 is formed, Al is deposited on the overcoat layer 38 by, for example, sputtering. Thereafter, a reflector 65 having concave reflecting surfaces 65a and 65b is formed by dry etching using a resist pattern. In addition, when forming by a base and a reflecting film, it can form by the same process as the reflective convex part 60 shown in FIG.

  Even when the reflector 65 is formed in this way, the reflector 65 is formed on the overcoat layer 38 made of an inorganic material as in the second embodiment. Damage to 37R, 37G, and 37B is prevented.

  Even in the organic EL device in which such a reflector 65 is formed, a part of the light emitted from the organic EL element 21 emitted toward the counter substrate 30 is directed toward the corresponding sub-pixel region 35. The light travels diagonally without going straight, and can be reflected toward the corresponding reflective layer 15 by the reflective surface 65a (65b) of the reflector 65 even between the sub-pixel regions 35 and 35. Therefore, by further reflecting on the reflective layer 15, the reflected light can be emitted from the corresponding sub-pixel region 35, and the light extraction efficiency can be further enhanced.

Further, since the reflecting surfaces 65a and 65b of the reflector 65 are concave surfaces that can collect light on the corresponding reflecting layer 15, the light reflected by these reflecting surfaces 65a and 65b is better for the corresponding reflecting layer 15 respectively. The light extraction efficiency can be further increased.
Furthermore, in this organic EL device, the reflector 65 can also serve as a black matrix layer (light shielding layer), and the manufacturing process of the counter substrate 30 can be simplified.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.
For example, in the above embodiment, the anode 10 is formed so as to overlap the reflective layer 15 in a plan view as shown by the solid line in FIGS. 2, 4, and 5, but FIG. 2, FIG. 4, and FIG. As shown by the middle two-dot chain line, the anode 10 is formed so as to be smaller than the reflective layer 15 in a plan view so that it is located inside the reflective layer 15 without going out of the reflective layer 15. May be.
In this way, light that passes through the anode 10 in an oblique direction and passes through the outside of the anode 10 and exits toward the planarization layer (underlying layer) 16 is also reflected by the reflective layer 15 and is reflected in the corresponding subpixel region 35. Can be directed.

Moreover, in the said embodiment, although the concave shape of the reflection layer 15 was formed in the inner surface shape of a ball | bowl, for example, only the peripheral part of this reflection layer may be made into a concave shape, and a center part may be formed flat.
In the second embodiment and the third embodiment, for example, the width between the sub-pixel regions 35 and 35 is made larger (wider) than the width (diameter) of the sub-pixel region 35 to extract emitted light from the organic EL element 21. The efficiency may be further increased.
Further, the diameter of the concave surface of the reflective convex portion 60 (reflective surfaces 60a and 60b) and the concave surface of the reflector 65 (reflective surfaces 65a and 65b) are made larger than the diameter of the concave surface of the reflective layer 15 to emit light from the organic EL element 21. The light extraction efficiency may be further increased.
Further, the reflection surfaces 60a and 60b of the reflection convex portion 60 and the reflection surfaces 65a and 65b of the reflector 65 may be formed in a flat surface without being formed in a concave surface.

Next, an electronic apparatus as an application example of the organic EL device in the present invention will be described by taking a mobile phone as an example. FIG. 6 is a perspective view showing the overall configuration of the mobile phone 600. The mobile phone 600 includes a housing 601, an operation unit 602 provided with a plurality of operation buttons, and a display unit 603 that displays images, moving images, characters, and the like. The display unit 603 is composed of the organic EL device of the present invention.
In this manner, since the display unit 603 includes the organic EL device with improved light extraction efficiency, the display performance of the electronic device (mobile phone) 600 can be improved.

  As electronic devices, in addition to the mobile phone 600, multimedia compatible personal computers (PCs), engineering workstations (EWS), pagers, word processors, televisions, viewfinder type or monitor direct view type video tapes. Examples include a recorder, an electronic notebook, an electronic desk calculator, a car navigation device, a POS terminal, and a touch panel.

DESCRIPTION OF SYMBOLS 1 ... Organic EL device (organic electroluminescence device), 10 ... Anode, 11 ... Cathode, 12 ... Functional layer, 15 ... Reflective layer, 15a ... Concave surface, 16 ... Flattening layer (underlayer), 20 ... Element substrate, 21 ... Organic EL element (organic electroluminescence element), 30 ... Counter substrate, 32 ... Black matrix layer (light-shielding layer), 35 ... Sub-pixel area (unit pixel area), 37 ... Color filter layer, 37R, 37G, 37B ... Coloring Layer, 60 ... Reflective convex part, 60a, 60b ... Reflective surface, 65 ... Reflector, 65a, 65b ... Reflective surface

Claims (8)

An organic electroluminescence device comprising an element substrate formed with an organic electroluminescence element having a functional layer including at least an organic light emitting layer between an anode and a cathode,
The anode and the cathode are both formed with translucency,
An organic electroluminescence device, wherein a reflective layer having a concave surface is provided on a base layer provided on a side of the anode opposite to the cathode so as to face the anode. The element substrate is provided with a plurality of organic electroluminescence elements,
A counter substrate in which a unit pixel region corresponding to the organic electroluminescence element is formed on the cathode side of the element substrate is disposed,
A light shielding layer is provided between the unit pixel regions;
A reflection convex portion having a reflection surface facing the reflection layer of the organic electroluminescence element corresponding to each unit pixel region adjacent to the light shielding layer is provided on the cathode side of the light shielding layer. The organic electroluminescence device according to claim 1.   The organic electroluminescence device according to claim 2, wherein the reflective surface of the reflective convex portion is a concave surface. The element substrate is provided with a plurality of organic electroluminescence elements,
A counter substrate in which a unit pixel region corresponding to the organic electroluminescence element is formed on the cathode side of the element substrate is disposed,
A reflector having a reflective surface facing the reflective layer of the organic electroluminescence element corresponding to each adjacent unit pixel region is provided on the cathode side between the unit pixel regions. Item 2. The organic electroluminescence device according to Item 1.   The organic electroluminescence device according to claim 4, wherein the reflecting surface of the reflector is a concave surface.   The organic electroluminescence device according to claim 1, wherein a color filter is provided in the unit pixel region.   The organic electroluminescence device according to any one of claims 1 to 6, wherein the underlayer is made of a planarizing layer.   The organic electroluminescence according to any one of claims 1 to 7, wherein the anode is located inside the reflective layer without coming out of the reflective layer in a plan view. apparatus.

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