JP2014157796A - Organic electroluminescence panel and organic el panel complex - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic EL panel in which a nonluminescent region resulting from a sealing structure on a substrate is inconspicuous.SOLUTION: An organic EL panel includes: a transparent board 2000 which has a shape from which two opposite corners of a square are removed; a luminescence function layer which is installed on the transparent board 2000 and includes an organic material; and a sealing structure 2006 which is made of a translucent material, connects with the transparent board 2000 in a peripheral region surrounding a luminous region of the transparent board 2000 in which the luminescence function layer is installed, and covers the luminescence function layer. When the width of the peripheral region is denoted by w, the sum of areas of the removed two corners is larger than (w/2).

Description

  The present invention relates to an organic electroluminescence (EL) panel and an organic EL panel composite in which a plurality of them are connected.

  In recent years, surface illumination devices using organic EL panels have been developed. FIG. 18 is a diagram showing a general structure assumed as a conventional organic EL panel. 18A is a top view, and FIG. 18B is a cross-sectional view taken along line AA in FIG.

  An organic layer formed by forming a patterned transparent electrode 2001 on a transparent substrate 2000 such as glass and laminating an electron injection layer, an electron transport layer, a light emitting layer, a hole transport layer, and a hole injection layer on a part of the transparent electrode 2001. 2002 is formed. In order to apply a voltage to the organic layer, a reflective electrode 2003 is formed on the organic layer. The reflective electrode 2003 is made of Al, Ag, or an alloy thereof having high reflectivity. Light is radiated to the outside from the extraction surface 2009 through the transparent substrate 2000. The extraction surface 2009 is provided with a light extraction structure such as a diffusion sheet 2007 in order to suppress total reflection of light. In this specification, a laminated structure including the transparent electrode 2001, the organic layer 2002, and the reflective electrode 2003 may be referred to as a light emitting functional layer.

  On the other hand, an organic material used for the organic layer 2002 is deteriorated in an environment of oxygen and moisture, and thus needs to be protected by covering with a sealing structure 2006. The sealing structure 2006 includes, for example, a sealing substrate 2004 that faces the reflective electrode 2003, and a sealing material 2005 that connects the sealing substrate 2004 and the transparent substrate 2000 in the peripheral region of the transparent substrate 2000.

  In order to apply a voltage to the organic EL, a power feeding unit 100 electrically connected to the transparent electrode 2001 and the reflective electrode 2003 through the sealing material 2005 and the transparent substrate 2000 is provided in the peripheral region of the transparent substrate 2000.

  In response to the demand for emitting a large area as a surface light source, when a plurality of organic EL panels are simply connected to obtain a single large area organic EL panel composite, Since there is a peripheral region where the power supply unit 100 and the sealing material 2005 that do not emit light exist, the joint between adjacent EL panels is conspicuous and the appearance of the organic EL panel composite is impaired.

  In order to solve this problem, for example, in Patent Document 1 and Patent Document 2, when a plurality of organic EL panels are connected, the position where the power feeding unit 100 of one organic EL panel sinks into the back surface of the other organic EL panel And a technique of omitting the power feeding part 100 of the upper organic EL panel in the connection part is disclosed. According to this technique, since the non-light-emitting region derived from the power feeding unit 100 in the connection unit is reduced, it is possible to make the joint inconspicuous.

JP 2001-126871 A JP-A-2005-123153

  However, if the power feeding unit 100 is simply placed at a position where it sinks into the back side of another organic EL panel according to the conventional technique, it is derived from a non-light emitting region provided in the outer peripheral portion of the organic EL panel in order to install the sealing material 2005. There is a problem that the joints still stand out.

  The present invention solves the above-described conventional problems, and when installing the organic EL panels in an overlapped manner, an organic EL panel in which a joint derived from a non-light-emitting region for installing a sealing material is less noticeable, and An object of the present invention is to provide an organic EL panel composite comprising a plurality of such organic EL panels.

In order to solve the above-described conventional problems, one aspect of the organic EL panel of the present invention includes a transparent substrate having a shape in which two corners located at opposite corners of a quadrangle are removed, and the transparent EL substrate disposed on the transparent substrate. A light-emitting functional layer containing an organic material, and a light-transmitting material, and the light-emitting functional layer is connected to the transparent substrate at a peripheral region surrounding the light-emitting region where the light-emitting functional layer is installed. The sum of the areas of the two removed corners is larger than (w / 2) ^{2 where} w is the width of the peripheral region.

  According to such a configuration, since the two corners located on the diagonal of the transparent substrate are removed, the two organic EL panels can be arranged at the same height by matching the diagonals. For example, when the upper two organic EL panels are arranged so as to overlap each other in the peripheral area along two adjacent sides of the lower organic EL panel, the upper and lower organic EL panels are brought into close contact with each other in the entire overlapping area. be able to. As a result, luminance unevenness that occurs when there is a non-uniform gap between the upper and lower organic EL panels in the overlapping region is eliminated, and the joints can be made inconspicuous.

Structure diagram of organic EL panel in Embodiment 1 of the present invention The figure explaining the integration | stacking of the extraction light quantity in Embodiment 1 of this invention The figure explaining the installation order of the organic electroluminescent panel in Embodiment 1 of this invention The figure explaining the installation order of the organic electroluminescent panel in Embodiment 1 of this invention The figure explaining the manufacturing method of the organic electroluminescent panel in Embodiment 1 of this invention Structure diagram of organic EL panel in Embodiment 2 of the present invention The figure explaining the propagation of the light in Embodiment 2 of this invention The figure explaining the extraction light quantity in Embodiment 2 of this invention The figure explaining the manufacturing method of the organic electroluminescent panel in Embodiment 2 of this invention The figure explaining the interference effect of the organic electroluminescent panel in Embodiment 3 of this invention The figure explaining the interference effect of the organic electroluminescent panel in Embodiment 3 of this invention The figure explaining the interference effect of the organic electroluminescent panel in Embodiment 3 of this invention The figure explaining the interference effect of the organic electroluminescent panel in Embodiment 3 of this invention The figure explaining the interference effect of the organic electroluminescent panel in Embodiment 3 of this invention The figure explaining the extraction light quantity in Embodiment 3 of this invention The figure which shows an example of the taking-out structure in Embodiment 4 of this invention The figure explaining the extraction light quantity in Embodiment 4 of this invention The figure which shows an example of the taking-out structure in Embodiment 4 of this invention The figure which shows an example of the taking-out structure in Embodiment 4 of this invention The figure which shows an example of the taking-out structure in Embodiment 4 of this invention Structural diagram of organic EL panel in modification of the present invention The figure explaining installation of the organic electroluminescent panel in the modification of this invention The figure which shows an example of the board | substrate removal part in the modification of this invention The figure which shows an example of the board | substrate removal part in the modification of this invention The figure which shows an example of the board | substrate removal part in the modification of this invention The figure which shows an example of the board | substrate removal part in the modification of this invention Structural diagram of organic EL panel in modification of the present invention Structural diagram of organic EL panel in modification of the present invention General assumed structure of conventional organic EL panel The figure explaining the extraction light quantity in the edge part vicinity of the light emission area | region of the conventional organic electroluminescent panel

  Prior to the description of the embodiments of the present invention, the results of investigations by the present inventor on an organic EL panel having a conventional configuration will be described.

  FIG. 19 shows an enlarged view near the boundary between the light emitting region and the peripheral region of the organic EL panel, and the amount of light extracted from the extraction surface 2009 of the transparent substrate 2000. Here, the light emitting region refers to a region where the light emitting functional layer of the transparent substrate 2000 is installed, and the peripheral region refers to a non-light emitting region surrounding the light emitting region of the transparent substrate 2000, and supplies power to the light emitting functional layer. This is an area on the transparent substrate where wiring and a sealing agent for fixing the sealing substrate are present. In the present application, it is the shortest distance from the outer periphery of the light emitting region to the outer shape of the transparent substrate, and usually 1 mm or more is required. When the light emitting area is not provided at the center of the transparent substrate, the light emitting area is the smallest of the widths of the peripheral areas on each side.

  Part of the light emitted from the light emitting layer travels along the path indicated by the arrow 502 while being reflected many times by total reflection in the transparent substrate 2000. At that time, light having an angle greater than the total reflection angle with respect to the transparent substrate 2000 is gradually extracted from the transparent substrate 2000 to the outside. Accordingly, a fade area 2008 in which the light amount gradually decreases occurs in the peripheral area. The width of the fade region 2008 varies depending on the light extraction structure such as the diffusion sheet 2007 and the distance from the light emitting layer to the extraction surface 2009 where the light extraction structure is installed.

  The amount of light at the joint where the organic EL panels are stacked is as follows.

  If the sealing material 2005 is non-translucent, the light from the organic EL panel arranged on the back surface is blocked, and the joints are conspicuous. By narrowing the width of the peripheral region where the sealing material 2005 is provided to the limit, it is possible to prevent the joints from being recognized by humans. In that case, however, the sealing performance is insufficient, and as a result, the lifetime of the organic EL is reduced. Because it becomes shorter, it is not realistic.

  By using a translucent material for the sealing material 2005, the result of integrating the light amounts in the respective fade regions 2008 of the stacked organic EL panels becomes the light amount at the joint of the organic EL panels. Therefore, it is possible to mitigate a decrease in the amount of light at the joint of the organic EL panel.

  However, as described above, there is a limit to narrowing the peripheral region where the sealing material 2005 is provided. Therefore, further measures are required to make the joint of the organic EL panel inconspicuous while securing the width of the peripheral region.

  In addition to the above, the present inventor has found the following situation as a factor that makes the joint of the organic EL panel conspicuous.

  In order for the joints of the organic EL panels to be inconspicuous, it is effective that the results of integrating the light amounts in the fade areas of the upper and lower organic EL panels are uniform in the area where the organic EL panels are overlapped.

  As an example, it is considered that two upper organic EL panels are arranged so as to overlap with a peripheral region along two adjacent sides of the lower organic EL panel. At this time, if the organic EL panel is a quadrangle, interference occurs so that the corner of the upper organic EL panel is cut into one end of the region where the upper organic EL panel is overlapped with the lower organic EL panel. To do. Then, the one organic EL panel on the upper side is inclined with respect to the take-out surface of the lower organic EL panel, and the width of the fade region is not uniform. As a result, the result of integrating the light amounts in the fade areas of the two upper and lower organic EL panels is not uniform over the entire overlapping area, resulting in uneven light intensity in the overlapping area. The seam becomes conspicuous due to such unevenness in the amount of light in the overlapping area.

The present invention has been made to solve such problems, and the organic EL panel according to one aspect of the present invention has a transparent shape in which two corners located at diagonally opposite sides of a square are removed. The transparent substrate in a peripheral region that is disposed on the transparent substrate and is composed of a light-emitting functional layer including an organic material and a light-transmitting material and surrounds the light-emitting region in which the light-emitting functional layer is disposed. And the sealing structure that covers the light emitting functional layer, and when the width of the peripheral region is w, the sum of the areas of the two removed corners is (w / 2) ² Greater than.

  The light emitting functional layer may be formed by laminating a transparent electrode, an organic layer including a light emitting layer, and a reflective electrode in this order on the transparent substrate.

  According to such a configuration, since the two corners located on the diagonal of the transparent substrate are removed, the two organic EL panels can be arranged at the same height by abutting against the diagonal. For example, when the upper two organic EL panels are arranged so as to overlap each other in the peripheral area along two adjacent sides of the lower organic EL panel, the upper and lower organic EL panels are brought into close contact with each other in the entire overlapping area. be able to. Thereby, luminance unevenness that occurs when there is a non-uniform gap between the upper and lower organic EL panels in the overlapping region can be eliminated, so that the joints of the organic EL panels are less noticeable. In addition, since the two organic EL panels are abutted diagonally, the light emitting areas of the organic EL panels can be arranged close to each other, so that the joints of the organic EL panels are less noticeable.

  Further, the organic EL panel is further electrically connected to the transparent electrode and the reflective electrode, and receives a power for emitting light from the light emitting functional layer from the outside, and transmits the power to the light emitting functional layer, A light extraction structure provided on a surface of the transparent substrate opposite to the surface on which the light emitting functional layer is disposed, and the power feeding unit extends along a pair of adjacent two sides of the organic EL panel It may be provided in a region excluding the peripheral region.

  According to such a configuration, the peripheral region in which the power feeding unit is not provided can be arranged so as to overlap another organic EL panel.

  The power feeding unit may be provided in the light emitting region.

  According to such a configuration, the width of the peripheral region can be reduced to the minimum width necessary for providing the sealing structure as compared with the case where the power feeding unit is provided in the peripheral region, so that the joint is not noticeable. It is effective for.

  The sealing structure is made of a sealing substrate made of glass and a light-transmitting resin, and a sealing material that connects the sealing substrate and the transparent substrate in the peripheral region of the transparent substrate; It may consist of

  According to such a configuration, it is possible to take out light from the organic EL panel located behind the superimposed through the sealing structure.

  Further, the sealing structure may be integrally formed of a light transmitting resin.

  According to such a configuration, it is possible to take out light from the organic EL panel located behind the superimposed through the sealing structure.

  The organic EL panel may further include a light extraction structure on a light extraction surface of the organic EL panel.

  According to such a configuration, light from the organic EL panel can be extracted through the light extraction structure.

Further, the sum of the areas of the two corners which are the removal may be greater than w ^2.

  According to such a configuration, since the two organic EL panels are faced diagonally, the light emitting regions of the organic EL panels can be arranged close to each other, so that the joints of the organic EL panels are not noticeable.

  The power feeding unit may be formed in the peripheral region, and the organic EL panel may further include a reflective film formed in the peripheral region where the power feeding unit is formed.

  According to such a configuration, the amount of light extracted from the peripheral region where the power feeding unit is formed for the reflective film is increased, and as a result, the joints are less noticeable.

  In addition, when light having a central wavelength λ is generated in the organic layer, the distance between the reflective electrode and the central emission position in the organic layer is (4m + 3) λ / 16 or more (4m + 5) λ / 16 or less, However, m may be an integer of 0 or more.

  According to such a configuration, the light emitted in the front direction of the organic EL panel is weakened by interference, and the light emitted to the wide angle side is strengthened by interference. As a result, the total amount of light guided through the transparent substrate is increased, and the attenuation of the amount of light around the light emitting region is moderated. Therefore, the alignment accuracy required when organic EL panels are stacked is relaxed. Moreover, since the width of the region where the amount of light attenuates in the periphery of the light emitting region is widened, the width of the sealing material can be widened, and the sealing performance of the organic EL can be further improved.

  Further, a light extraction layer may be provided between the transparent substrate and the transparent electrode.

  According to such a configuration, light from the light emitting layer can be extracted through the light extraction layer.

  In addition, the organic EL panel composite according to one aspect of the present invention includes a plurality of organic EL panels that are a plurality of the above-described organic EL panels and in which peripheral regions of adjacent organic EL panels are arranged to overlap each other, A light extraction surface that covers the light extraction surfaces of the plurality of organic EL panels flatly and is formed of a transparent resin, and a light extraction surface that is attached to the flat surface on the opposite side of the organic EL panel of the planarization layer. A layer.

  According to such a configuration, a large-area organic EL panel composite in which ends of a plurality of organic EL panels are overlapped is obtained.

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1 is a structural diagram of an organic EL panel according to Embodiment 1 of the present invention. 1A is a top view, and FIG. 1B is a cross-sectional view taken along line AA in FIG. In FIG. 1, the same components as those in FIG.

  In FIG. 1, the power feeding unit 100 is installed on two adjacent sides, and is configured in a region that is not covered with another organic EL panel when the organic EL panels are overlapped. In addition, substrate removal portions 101a and 101b are provided on opposite sides of the organic EL panel so as to fit each other, and the sealing substrate 2004 and the sealing material 2005 are made of a material that can transmit light.

  FIG. 2 is a structural diagram of the boundary between the light emitting region of the organic EL panel and the region where the sealing material is installed, and a graph showing the distribution of the amount of light extracted from the region. FIG. 2 shows the transparent substrate 2000a, the transparent electrode 2001a, the organic layer 2002a, the reflective electrode 2003a, the sealing substrate 2004a, the sealing material 2005a, and the second organic EL panel 200b of the first organic EL panel 200a. A transparent substrate 2000b, a transparent electrode 2001b, an organic layer 2002b, a reflective electrode 2003b, a sealing substrate 2004b, and a sealing material 2005b are shown. When the organic EL panel is viewed from the top, the outline of the transparent substrate 2000b and the transparent electrode 2001b is larger than the outline of the sealing substrate 2004b, and a portion of the transparent substrate 2000b and the transparent electrode 2001b that is not covered with the sealing substrate 2004b is shown. The power supply unit 100b is configured.

  The width of the fade region 2008a of the first organic EL panel 200a is determined by the distance between the diffusion sheet 2007a and the light emitting layer generated in the organic layer 2002a and the property of the diffusion sheet 2007a.

  An index indicating the properties of the diffusion sheet 2007a includes a haze value. The definition of the haze value is the ratio of the diffused light intensity to the total transmitted light intensity. In the present embodiment, a sheet having a haze value of 75% was selected and examined. If the sheet characteristics are uniform, the fade area 2008a where the amount of light at the boundary decreases depends on the thickness of the transparent substrate 2000a, and therefore has a uniform width regardless of the location.

  On the other hand, in the fade region 2008b of the second organic EL panel 200b, light emitted from the light emitting layer generated in the organic layer 2002b passes through the sealing structure 2006a of the first organic EL panel 200a and is diffused by the diffusion sheet 2007a. Is formed. Therefore, the width of the fade region 2008b of the organic EL panel 200b varies depending on the distance between the light emitting layer and the diffusion sheet 2007a.

  Since the thickness of the transparent substrate 2000b, the sealing substrate 2004a, and the sealing material 2005a is added in addition to the thickness of the transparent substrate 2000a, the width of the fade region 2008b is larger than the width of the fade region 2008a. The sum of the extracted light amounts of the fade areas 2008a and 2008b is the luminance of the boundary portion. Since the width of the fade area 2008a and the width of the fade area 2008b do not completely coincide with each other, the integrated light quantity does not become a constant value, but the connection portion can be made inconspicuous if it is less than a permissible value perceivable by humans. .

  Further, if the gaps between the panels are opened or are not uniform when they are overlapped, the width of the fade area 2008b changes depending on the location. Therefore, in order to make the connection portion inconspicuous by overlapping, the gap between the panels to be overlapped must be uniform.

  FIG. 3 shows the order of installation of the organic EL panel of the present invention. The organic EL panel is seen from the back side, and light is emitted to the back side of the paper.

  First, the organic EL panel 200a is installed (FIG. 3A).

  The organic EL panels 200b and 200c are installed so that portions other than the power supply units 100b and 100c overlap the power supply unit 100a of the organic EL panel 200a (FIG. 3B).

  At this time, since the substrate removal portions 101b and 101c are formed on the diagonal of the substrate, the organic EL panels 200b and 200c can be installed at the same height with respect to the organic EL panel 200a without interfering with each other. it can. Unlike the case where the substrate removing portions 101b and 101c are not provided, the substrates are not overlapped, and there is no gap between the organic EL panels 200a and 200b or between the organic EL panels 200a and 200c. Furthermore, since the organic EL panels 200b and 200c have the same height, the organic EL panel 200d has the same height with respect to each of the organic EL panels 200b and 200c when the organic EL panels 200d are stacked. .

  In this way, by stacking the panels, the height of the organic EL panels arranged in the diagonal direction can always be made constant. Such a laminating method is not limited to four sheets, and can be applied to the case of four or more sheets by superimposing a power feeding part on a part without a power feeding part.

  As shown in FIG. 4, it is not necessary to arrange the organic EL panel horizontally with respect to the installation surface, and by tilting the whole, the total thickness is suppressed to t or less regardless of how many organic EL panels are stacked. be able to.

  FIG. 5 is a process diagram illustrating an example of a method for manufacturing an organic EL panel. First, a transparent substrate 2000 from which a part of the diagonal is removed is prepared (FIG. 5A), and a transparent electrode 2001 made of ITO (Indium Tin Oxide) or the like is formed on the transparent substrate 2000. A part of the transparent electrode 2001 is removed at the separation part 400 to form the power feeding part 100 (FIG. 5B). On the patterned transparent electrode 2001, the organic layer 2002 is formed so as to overlap the separation part 400 from which the transparent electrode has been removed (FIG. 5C). A reflective electrode 2003 is formed on the organic layer 2002 (FIG. 5D). With such a structure, a short circuit between the reflective electrode 2003 and the transparent electrode 2001 can be prevented. After that, a sealing material 2005 made of a UV curable material or the like is applied so as to surround the organic layer 2002 (FIG. 5E), and the sealing substrate 2004 is bonded and fixed.

  Note that FIG. 5 shows an example of a manufacturing method in which the outer shape of the substrate is processed first. However, the manufacturing method is not limited thereto, and for example, a plurality of organic EL panels are simultaneously manufactured on a large-area substrate, and finally, The substrate may be cut.

  It is also known that total reflection occurs due to a difference in refractive index between the transparent electrode 2001 and the transparent substrate 2000 of the organic EL panel. Not only the diffusion sheet 2007 on the surface of the transparent substrate 2000 but also a takeout structure such as a diffraction grating or a nanostructure may be provided between the transparent substrate 2000 and the transparent electrode 2001. The effect of the present invention can also be obtained in an organic EL panel having such a configuration.

  Note that in order to further increase the efficiency of electron injection from the reflective electrodes 2003a and 2003b, a thin film such as a lithium (Li) compound that is a low work function material may be stacked so as to be in contact with the reflective electrodes 2003a and 2003b. In addition, when silver is used for the material of the reflective electrodes 2003a and 2003b, the electron injection efficiency can be increased by mixing magnesium (Mg) with silver. However, since the refractive index of silver and the refractive index of magnesium are close to each other, the reflective electrodes 2003a and 2003b made of silver and the reflective electrodes 2003a and 2003b made of silver and magnesium have almost the same optical characteristics. is there. Therefore, for example, when using silver mixed with magnesium as the material of the reflective electrodes 2003a and 2003b, a configuration using a material whose optical characteristics are almost the same as that of the silver alone as the material of the reflective electrodes 2003a and 2003b is included in this embodiment. It is.

  The transparent electrodes 2001a and 2001b are anodes having optical transparency. When a voltage is applied between the reflective electrodes 2003a and 2003b and the transparent electrodes 2001a and 2001b, holes (or electrons) are injected from the transparent electrodes 2001a and 2001b into the organic layers 2002a and 2002b. As materials for the transparent electrodes 2001a and 2001b, materials such as ITO (indium tin oxide), IZO (indium zinc oxide), and PEDOT: PSS (mixture of polythiophene and polystyrene sulfonic acid) can be used. Further, even when the material itself is not transparent, by processing a conductor such as silver (Ag) and aluminum (Al) to a film thickness of 100 nm or less, a light-transmitting conductor can be formed. This can also be used as the transparent electrodes 2001a and 2001b.

  The organic layers 2002a and 2002b are configured by stacking an electron transport layer, a light emitting layer, a hole transport layer, and the like (not shown) in this order. The electron transport layer is disposed on the reflective electrodes 2003a and 2003b, and the hole transport layer is disposed on the transparent electrodes 2001a and 2001b. In the case where the reflective electrodes 2003a and 2003b are used as anodes, the electron transport layer is disposed on the transparent electrode 2001 side, and the hole transport layer is disposed on the reflective electrode 2003 side. The electron transport layer is made of, for example, tris (8-quinolylato) aluminum complex (Alq3). The hole transport layer is made of a diamine derivative such as NPB, for example. The light emitting layer is composed of, for example, a tris (4-methyl-8-quinolinato) aluminum complex.

(Embodiment 2)
FIG. 6 is a structural diagram of the organic EL panel according to the second embodiment of the present invention. 6A is a top view, and FIG. 6B is a cross-sectional view taken along line AA in FIG. In FIG. 6, the same components as those in FIG. The difference between the present embodiment and the first embodiment is that a reflective film 500 is provided in the power feeding portion in accordance with the patterned electrode.

  With reference to FIG. 7, the propagation of light at the light emitting region boundary and the effect of the reflective film 500 will be described. As shown in FIG. 19, in the case where there is no reflective film 500, the light reflected and returned from the surface among the light emitted in the substrate direction passes along the path indicated by the arrow 501 to the sealing substrate side, It cannot be taken out. However, by providing the reflection film 500 in the power feeding portion, it can be reflected toward the transparent substrate 2000 along the path indicated by the arrow 502 and taken out to the outside. On the other hand, the lower substrate preferably transmits light. That is, it is better not to provide a reflective film on the sealing material on the opposite side of the power feeding unit.

  FIG. 8 shows the light and the extraction amount at the boundary of the light emitting region when the reflective film is provided. The broken line indicates the change in the amount of light for each place before the reflection film is provided, and the solid line indicates the change in the light amount when the reflection film is provided. Compared with the fade area 2008b in the case where the reflective film is not provided, the fade area 2008c in the case where the reflective film is provided uses light more effectively, and as a result, the total amount of light that can be extracted increases, resulting in a slow attenuation. Therefore, the alignment accuracy required in the case of overlapping is eased. Moreover, since the area | region to which it attenuate | damps becomes large, the width | variety of a sealing material can be widened and the sealing performance of organic EL can be improved.

  FIG. 9 shows a method for manufacturing the organic EL panel of this embodiment. The difference from Embodiment 1 is that after forming the patterned transparent electrode 2001, the reflective film 500 was formed avoiding the separation part 400 (FIG. 9C). Other steps can be manufactured in the same manner as in Embodiment Mode 1.

(Embodiment 3)
In the present invention, light guided through the transparent substrate 2000 is utilized in order to make the boundary of the connection portion of the organic EL panel inconspicuous. The ratio of the light that is guided in the transparent substrate 2000 by changing the light distribution pattern of the light emitted from the light emitting layer by changing the distance d between the center light emitting position of the light emitting layer and the reflective electrode 2003 generated in the organic layer 2002. Can be increased.

  A part of the light generated in the light emitting layer goes directly to the air layer, and another part of the light generated in the light emitting layer is reflected by the reflective electrode 2003 and then goes to the air layer. Since these lights interfere with each other, the pattern of light emitted from the light emitting layer changes depending on the distance d between the central light emitting position and the reflective electrode 2003.

  The light intensity I (θ) in the θ direction is expressed by Equation 1, where θ is the light emission direction, d is the distance between the center emission position and the reflective electrode, and λ is the center emission wavelength of the light.

  10A to 10E respectively show the distribution of light distribution at the central light emission position S in the case of d / λ = 1/8, 3/16, 2/8, 5/16, and 3/8. FIG. For example, as shown in FIG. 10A, when d / λ = (2m + 1) / 8 (m is an integer greater than or equal to 0), the light in the front direction is enhanced by interference. For example, as shown in FIG. 10C, when d / λ = (2 m) / 8 (m is an integer equal to or greater than 1), the light in the front direction is weakened by interference, and when d / λ = 1/8 The intensity in the front direction becomes half or less, and the light on the wide angle side is strengthened by interference. Note that the light distribution of the light generated at the central light emission position S is the light distribution shown in FIGS. 10A to 10E regardless of the presence or absence of the light extraction structure.

  In view of this, an organic EL panel in which the distance between the light-emitting layer where the light guided through the transparent substrate 2000 increases and the reflective electrode is larger than 3 / 16λ and smaller than 5 / 16λ was studied.

  FIG. 11 shows a light amount distribution (dashed line) at the boundary of the light emitting region when a reflective film is not provided in a conventional light distribution organic EL panel (corresponding to the light distribution A) with a distance between the light emitting layer and the reflective electrode of 70 nm. Light quantity distribution (dotted line) at the boundary of the light emitting region and the distance between the light emitting layer and the reflective electrode when a reflective film is provided in a conventional light distribution organic EL panel (corresponding to the light distribution A) with a distance of 70 nm from the reflective electrode Shows a light amount distribution (solid line) when a reflective film is provided on an organic EL panel (corresponding to the light distribution B) prototyped at 110 nm.

  In the panel corresponding to the light distribution B in which the light distribution pattern is changed, the total amount of light guided through the transparent substrate 2000 is increased, and the attenuation is moderate compared to the panel corresponding to the light distribution A. Therefore, the accuracy required for alignment required when organic EL panels are stacked is relaxed. In addition, since the width of the area where the amount of light attenuates around the light emitting area, that is, the fade area described above is widened, the width of the sealing material can be widened, and the sealing performance of the organic EL can be further improved. it can.

(Embodiment 4)
The position where the take-out structure is provided need not be limited to the surface of the transparent substrate 2000. In general, the refractive index of the organic layer 2002 and the transparent electrode 2001 is 1.8 or more, and total reflection occurs at the interface with the transparent substrate 2000. In order to suppress this total reflection, a take-out structure may be provided inside the organic EL panel. By applying the embodiment of the present invention to such an organic EL panel, it is possible to obtain an effect of making the joint of the organic EL panel inconspicuous. As the extraction structure, a concavo-convex structure capable of performing angle conversion of light, such as a diffraction grating, a microlens, or a pyramid structure, can be used. Further, the extraction structure is not limited to one layer, and may be provided on a plurality of surfaces through which light passes.

  Further, in the third embodiment, the light distribution pattern is changed depending on the distance between the central light emission position and the reflective electrode. However, the light distribution pattern is also obtained by the extraction structure provided between the transparent electrode 2001 and the transparent substrate 2000. Can be changed.

  12B shows a thin-film extraction structure (FIG. 12A) in which unit structures having a size p of 0.4, 1, 2, 5, 10 μm are periodically arranged at the interface between the transparent electrode 2001 and the transparent substrate 2000. It is a graph which shows an example of the light intensity distribution of the provided organic electroluminescent panel. In FIG. 12A, black and white color coding corresponds to a difference in optical characteristics (for example, thickness and refractive index) of the unit structure.

  When the extraction structure is not provided, the light intensity is almost the same regardless of the angle, but it can be seen that the intensity of the extracted light is increased by providing the extraction structure. Further, by changing the period of the unit structure, the intensity of light on the wide angle side is increased, and wide-angle light distribution can be realized by the structure.

  Also, the structure need not be limited to a periodic arrangement. For example, as shown in FIG. 13A, when a take-out structure in which unit structures of 0.6, 3, and 10 μm in size are arranged at random is manufactured and the light distribution is measured, the light distribution is controlled by the structure in the same manner. I was able to. Furthermore, the arrangement is not limited to the arrangement shown in FIG. 13A, and it is possible to use an extraction structure in which a low frequency component is removed from a random structure as shown in FIG. 13B or an extraction structure in which hexagonal unit structures are arranged as shown in FIG. 13C. A similar effect can be obtained.

(Modification)
In the embodiment of the present invention, the description has been made using the structure in which the organic layer is protected from moisture and oxygen by the transparent sealing material and the sealing substrate. However, the sealing method needs to be limited to this structure. However, the same effect can be obtained as long as the structure transmits light.

  For example, as illustrated in FIG. 14, the sealing structure 2006 may be a transparent resin 1101 that functions as the sealing substrate 2004 and the sealing material 2005, and the organic EL is integrally formed with such a sealing structure 2006. The panel may be sealed. With such a configuration, the manufacturing process can be simplified.

  Further, in the embodiment of the present invention, the embodiment in which the take-out sheet is not provided on the substrate of the first organic EL panel 200a that overlaps the second organic EL panel 200b is shown. It is not necessary to limit, and a diffusion sheet may be installed in a portion where the takeout sheet overlaps on the second organic EL panel. Further, since the sealing material and the sealing substrate are light transmissive, they may be disposed so as to overlap with the light emitting region of the first organic EL panel 200a that is below the overlapping portion.

  Further, it is not necessary to attach the diffusion sheet to the organic EL panel in advance. As shown in FIG. 15, after arranging a plurality of organic EL panels 1401 side by side, the entire organic EL panel is embedded with a transparent adhesive resin 1402 and arranged. Diffusion sheets 1403 that match the size of these may be installed in a batch.

  Moreover, the diagonal board | substrate removal part of an organic electroluminescent panel does not need to be cut off with the straight line. The effect of the present invention can be obtained if the substrate removal portion has a shape that allows adjacent organic EL panels to fit together without gaps and can provide a sealing region having a desired width at the diagonal portion of the organic EL panel.

  When the substrate removal portion is cut off by a straight line, as shown in FIG. 16A, slippage occurs in the direction of the arrow when the organic EL panel is installed, and the position is easily displaced. For example, as shown in FIG. 16B, the misalignment can be prevented by making the fitting portion difficult to slip in an oblique direction. Further, the fitting portion does not necessarily need to be composed of only the same material as the substrate. As shown in FIG. 16C, a separate transparent member (for example, a positioning transparent member provided in advance on a base material to be attached) may be used. Moreover, as shown to FIG. 16D, in order to ensure the width | variety which provides a sealing area | region in the diagonal part of an organic electroluminescent panel, you may provide a board | substrate removal part more narrowly.

  If the width of the overlapping region of the two organic EL panels is reduced with respect to the width w of the peripheral region, a conspicuous region is generated at the connection portion even if the extracted light amounts in the fade regions of the two organic EL panels are integrated. End up. Therefore, for example, the sum of the areas of the two corners to be removed is preferably larger than (w / 2) 2.

  While the organic EL panel according to one or more aspects of the present invention has been described based on the embodiment, the present invention is not limited to this embodiment. Unless it deviates from the gist of the present invention, one or more of the present invention may be applied to various modifications that can be conceived by those skilled in the art, or forms constructed by combining components in different embodiments. It may be included within the scope of the embodiments.

  FIG. 17A is a structural diagram in the vicinity of an overlapping region of an organic EL panel according to a modification. The difference from the structure shown in FIG. 2 is that the diffusion sheet 2007 of the second organic EL panel 200b extends to the overlapping portion of the second organic EL panel 200b and the first organic EL panel 200a. It is that you are.

  FIG. 17B is a structural diagram in the vicinity of an overlapping region of an organic EL panel according to a modification. The difference from the structure shown in FIG. 7 is that the diffusion sheet 2007 of the second organic EL panel 200b extends to the overlapping portion of the second organic EL panel 200b and the first organic EL panel 200a. It is that you are.

  The organic EL panel according to the present invention can be used as surface illumination in which a plurality of panels are arranged to emit light in a free shape. The organic EL panel according to the present invention can be applied to, for example, flat panel displays, liquid crystal display backlights, illumination light sources, and the like. In addition, the organic EL panel according to the present invention is not limited to a monochromatic light source, and can also be applied to a white light emitting device.

100, 100a, 100b Power supply unit 101a, 101b Substrate removal unit 200a, 200b, 200c, 200d, 1401 Organic EL panel 400 Separating unit 500 Reflective film 501, 502 Arrow 1101 Resin 1402 Adhesive resin 1403 Diffusion sheet 2000, 2000a, 2000b Transparent substrate 2001, 2001a, 2001b Transparent electrode 2002, 2002a, 2002b Organic layer 2003, 2003a, 2003b Reflective electrode 2004, 2004a, 2004b Sealing substrate 2005, 2005a, 2005b Sealing material 2006, 2006a, 2006b Sealing structure 2007, 2007a, 2007b Diffusion sheet 2008, 2008a, 2008b, 2008c Fade area 2009 Extraction surface

Claims (12)

A transparent substrate having a shape in which two corners located at opposite corners of a rectangle are removed;
A light emitting functional layer disposed on the transparent substrate and containing an organic material;
A sealing structure made of a translucent material and connected to the transparent substrate in a peripheral region surrounding the light emitting region where the light emitting functional layer of the transparent substrate is installed, and covering the light emitting functional layer,
An organic EL panel in which the sum of the areas of the two removed corners is greater than (w / 2) ^{2 where} w is the width of the peripheral region. The organic EL panel according to claim 1, wherein the light emitting functional layer is formed by laminating a transparent electrode, an organic layer including a light emitting layer, and a reflective electrode in this order on the transparent substrate. further,
A power feeding unit that is electrically connected to the transparent electrode and the reflective electrode, receives power from the outside for emitting light from the light emitting functional layer, and transmits the power to the light emitting functional layer;
A light extraction structure provided on a surface opposite to the surface on which the light emitting functional layer of the transparent substrate is installed,
The organic EL panel according to claim 1, wherein the power feeding unit is provided in a region excluding the peripheral region along a pair of adjacent two sides of the organic EL panel. The organic EL panel according to claim 1, wherein the power feeding unit is provided in the light emitting region. The sealing structure includes a sealing substrate made of glass and a sealing material that is made of a translucent resin and connects the sealing substrate and the transparent substrate in the peripheral region of the transparent substrate. The organic electroluminescent panel of any one of Claim 1 to 4. The organic EL panel according to claim 1, wherein the sealing structure is integrally formed of a translucent resin. The organic EL panel according to any one of claims 1 to 6, further comprising a light extraction structure on a light extraction surface of the organic EL panel. The organic EL panel according to claim 1, wherein the sum of the areas of the two removed corners is greater than w ² . The feeding portion is formed in the peripheral region;
Furthermore, the organic electroluminescent panel of any one of Claim 1 to 8 provided with the reflecting film formed in the peripheral region in which the said electric power feeding part was formed. When light having a central wavelength λ is generated in the organic layer, the distance between the reflective electrode and the central light emission position in the organic layer is (4m + 3) λ / 16 or more and (4m + 5) λ / 16 or less, where m 10 is an integer greater than or equal to 0. The organic EL panel according to any one of claims 1 to 9. The organic EL panel according to any one of claims 1 to 10, wherein a light extraction layer is provided between the transparent substrate and the transparent electrode. A plurality of organic EL panels according to any one of claims 1 to 10, wherein the peripheral regions of adjacent organic EL panels are overlapped with each other,
A flattening layer that covers the light extraction surfaces of the plurality of organic EL panels flatly and is made of a transparent resin;
An organic EL panel composite comprising: a light extraction layer attached to a flat surface opposite to the organic EL panel of the flattening layer.

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