JP7486052B2 - Organic EL display device, transmission control panel, and method for manufacturing the transmission control panel - Google Patents

Description

The present invention relates to an organic EL display device, a transmission control panel, and a method for manufacturing a transmission control panel.

Organic EL display devices equipped with organic EL elements have been proposed in the field of flat panel displays and other displays, and research into their applications is being actively conducted. It is known that in conventional organic EL display devices, external light entering the organic EL display device from the surroundings is reflected by the internal structure of the organic EL display device. In such cases, there are problems such as the surrounding scenery being reflected in the display in bright environments and a decrease in the contrast ratio due to the reflection of external light.

As a method for solving the above problem, an organic EL display device in which a circular polarizing plate is arranged on the light exit surface side has been proposed, as disclosed in, for example, Patent Document 1 and Patent Document 2. The circular polarizing plate is composed of a retardation plate that functions as a quarter-wave plate and a polarizing plate that is located on the light exit surface side of the retardation plate. The circular polarizing plate works as follows. When external light incident on the organic EL display device from the surroundings passes through the polarizing plate, linearly polarized light with a polarization plane in a specific direction is transmitted, and linearly polarized light with a polarization plane perpendicular to this is absorbed. The linearly polarized light that has passed through the polarizing plate is subjected to the action of the retardation plate, and becomes circularly polarized light with a rotating polarization plane. When the light that has passed through the retardation plate is reflected by the internal structure of the organic EL display device, it becomes circularly polarized light with the opposite rotation direction. The reflected light enters the retardation plate again, and as it passes through it, it is converted into linearly polarized light by its action and is absorbed by the polarizing plate this time, so it does not return to the outside.

Japanese Patent Application Laid-Open No. 8-321381 JP 2004-30955 A

In an organic EL display device equipped with a circular polarizer, only one polarized component of the light emitted by the organic EL element is transmitted through the polarizer. As a result, the ratio of light emitted by the organic EL element to the light emitted by the organic EL display device (hereinafter also referred to as the light output rate) is less than half.

The present invention has been made in consideration of these points, and aims to provide an organic EL display device that can improve the light output rate while suppressing external light reflection.

The organic EL display device according to the present invention comprises a plurality of organic EL elements, an electrical circuit section used to drive the organic EL elements, and a transmission control panel arranged on the light emission side of the organic EL elements from the electrical circuit section, the transmission control panel having an element light transmission region facing at least a portion of the organic EL elements, and a transmission restriction region facing at least a portion of the electrical circuit section and having a visible light transmittance lower than that of the element light transmission region.

In the organic EL display device according to the present invention, the organic EL element, the electrical circuit section, and the transmission control panel may be arranged in this order, facing the outside where the light from the organic EL element is emitted.

In the organic EL display device according to the present invention, the electrical circuit section, the organic EL element, and the transmission control panel may be arranged in this order, facing the outside where the light from the organic EL element is emitted.

In the organic EL display device according to the present invention, the transmission-restricting region may have a first region facing at least a portion of the electrical circuit section, and a second region facing a portion of the organic EL element.

In the organic EL display device according to the present invention, the organic EL elements include at least a plurality of first elements for emitting light of a first color and a plurality of second elements for emitting light of a second color, and the second region may face the plurality of first elements.

In the organic EL display device according to the present invention, the first element may emit white light.

In the organic EL display device according to the present invention, the first element may emit white light through a white pixel portion provided in a color filter, and the second region may face the first element through the white pixel portion.

In the organic EL display device according to the present invention, the second region may have a higher visible light transmittance than the first region.

In the organic EL display device according to the present invention, the first region may have a visible light transmittance of 0% or more and 5% or less, and the second region may have a visible light transmittance of 30% or more and 50% or less.

In the organic EL display device according to the present invention, the transmission control panel may have a first transmission limiting layer in the first region and a second transmission limiting layer in the second region that is thinner than the first transmission limiting layer.

In the organic EL display device according to the present invention, the transmission control panel has a transmission section and a transmission limiting section having a visible light transmittance lower than that of the transmission section in the first region and the second region, respectively, and when viewed in a direction in which light is emitted from the organic EL element, the ratio of the area of the transmission limiting section in the first region to the area of the first region may be greater than the ratio of the area of the transmission limiting section in the second region to the area of the second region.

The transmission control panel according to the present invention is a transmission control panel provided in an organic EL display device having a plurality of organic EL elements and an electrical circuit section used to drive the organic EL elements, and is provided with an element light transmission region that faces at least a portion of the organic EL elements when the transmission control panel is provided in the organic EL display device, and a transmission restriction region that faces at least a portion of the electrical circuit section when the transmission control panel is provided in the organic EL display device and has a visible light transmittance lower than that of the element light transmission region.

The method for manufacturing a transmission control panel according to the present invention is a method for manufacturing a transmission control panel provided in an organic EL display device having a plurality of organic EL elements and an electric circuit section used to drive the organic EL elements, and includes the steps of forming a sheet-like transmission layer having a recess that faces at least a part of the electric circuit section when the transmission control panel is provided in the organic EL display device, and forming a transmission limiting layer in the recess, and the material of the transmission limiting layer has a visible light transmittance lower than that of the material of the transmission layer when compared at the same thickness.

In the method for manufacturing a transmissive control panel according to the present invention, the recess has a first bottom surface that faces at least a part of the electrical circuit section when the transmissive control panel is provided on the organic EL display device, and a second bottom surface that faces a part of the organic EL element when the transmissive control panel is provided on the organic EL display device, and the thickness of the transmissive layer in a region where the first bottom surface is located may be smaller than the thickness of the transmissive layer in a region where the second bottom surface is located.

The method for manufacturing a transmission control panel according to the present invention is a method for manufacturing a transmission control panel provided in an organic EL display device having a plurality of organic EL elements and an electrical circuit section used to drive the organic EL elements, and includes the steps of forming a sheet-like transmission section that faces at least a portion of the electrical circuit section when the transmission control panel is provided in the organic EL display device and has an opening area including a plurality of openings, and forming a transmission limiting section within the opening that has a visible light transmittance lower than that of the transmission section.

In the method for manufacturing a transmission control panel according to the present invention, the opening region has a first opening region that faces at least a part of the electrical circuit section when the transmission control panel is provided on the organic EL display device, and a second opening region that faces a part of the organic EL element when the transmission control panel is provided on the organic EL display device, and when viewed in a direction in which light is emitted from the organic EL element, the ratio of the area of the opening in the first opening region to the area of the first opening region may be greater than the ratio of the area of the opening in the second opening region to the area of the second opening region.

The present invention provides an organic EL display device that can improve light output while suppressing external light reflection.

FIG. 1 is a diagram for explaining one embodiment of the present invention, and is a partial cross-sectional view showing a schematic configuration of an organic EL display device. 2 is a plan view showing the positions of a drive circuit section and an organic EL element in the organic EL display device of FIG. 1; 3 is a plan view showing the positions of a drive circuit section and an organic EL element in the organic EL display device of FIG. 1, as well as the shapes of a transmission limiting region and an element light transmitting region of a transmission control panel. FIG. 4 is a partial cross-sectional view showing a schematic configuration of an organic EL display device according to a first modified example. FIG. 5 is a partial cross-sectional view showing a schematic configuration of an organic EL display device according to a second modified example. FIG. 6 is a plan view showing a schematic configuration of an organic EL display device according to a third modified example. FIG. 7 is a partial cross-sectional view showing a schematic configuration of an organic EL display device according to a fourth modified example.

An embodiment of the present invention will be described with reference to the drawings. Note that in the drawings attached to this specification, the scale and aspect ratios have been appropriately altered and exaggerated from those of the actual objects for the sake of ease of illustration and understanding.

FIG. 1 is a diagram for explaining one embodiment of the present invention, and is a partial cross-sectional view showing a schematic configuration of an organic EL display device 1. The organic EL display device 1 according to this embodiment includes an element layer 14 having an organic EL element 11, a circuit layer 24 having an electric circuit section 20 used to drive a plurality of organic EL elements 11, and a transmission control panel 30 arranged on the light emission side of the organic EL element 11 from the electric circuit section 20. The element layer 14 includes a plurality of organic EL elements 11 therein, and the circuit layer 24 includes the electric circuit section 20 therein. The organic EL display device 1 according to this embodiment is a bottom emission type, and a circuit layer 24 having an electric circuit section 20 is arranged on the light emission side of the organic EL element 11 from the organic EL element 11, and light from the organic EL element 11 is emitted through the electric circuit section 20 (circuit layer 24) toward the outside where a viewer of the display image is located. The transmission control panel 30 is arranged so as to cover the electric circuit section 20 from the outside, and in this embodiment, the organic EL element 11, the electric circuit section 20, and the transmission control panel 30 are arranged in this order toward the outside where the light from the organic EL element 11 is emitted. Note that the "light emission side of the organic EL element 11" means the outside side where the above-mentioned light is emitted, that is, the viewer side, and means the upper side in FIG. 1. For example, arranging the transmission control panel 30 on the light emission side of the organic EL element 11 from the electric circuit section 20 means that the transmission control panel 30 is arranged on the viewer side from the electric circuit section 20. In the following description, the "light emission side of the organic EL element 11" is also simply referred to as the "light emission side". As shown in FIG. 1, the organic EL display device 1 according to this embodiment further includes a substrate 5, a color filter 40, a barrier layer 4, an alloy plate 2, an adhesive layer 3 that bonds the barrier layer 4 and the alloy plate 2, and a hard coat 6. In this embodiment, the circuit layer 24 is arranged on the light emission side from the color filter 40.

First, the circuit layer 24 will be described. The circuit layer 24 contains an electric circuit section 20 used to drive the organic EL element. In the example shown in FIG. 1, the circuit layer 24 further includes an insulating layer 23 that covers the electric circuit section 20 from the side opposite to the light emission side. There are no particular limitations on the material of the insulating layer 23, so long as it has insulating properties.

As an example, the electric circuit section 20 will be described when the organic EL display device 1 employs an active matrix method for driving each organic EL element 11. In this case, the electric circuit section 20 includes a drive circuit 21 and drive wiring 22.

The drive circuit 21 is provided for each organic EL element 11, and is a circuit that drives each organic EL element 11. In the example shown in FIG. 1, the drive circuit 21 is disposed on the surface of the substrate 5, which will be described later, on the side on which the organic EL element 11 is located. The drive circuit 21 includes a drive element such as a transistor T for driving the organic EL element 11. As a result, the substrate 5 on which the drive circuit 21 is provided is a substrate for driving the organic EL element 11, a so-called TFT substrate. When the drive circuit 21 controls the drive current to flow from the anode to the cathode of the organic EL element 11, the light-emitting layer of the organic EL element 11 emits light.

The transistor T will be described in detail with reference to FIG. 1. In the example shown in FIG. 1, each transistor T has a source electrode 25 and a drain electrode 26 spaced apart on the surface of the substrate 5 on which the organic EL element 11 is disposed, and a semiconductor layer 27 disposed on the surface of the substrate 5 on which the organic EL element 11 is disposed so as to be located between adjacent source electrodes 25 and drain electrodes 26. Although not shown, the transistor T further has a gate electrode disposed on the surface of the insulating layer 23 on which the organic EL element 11 is disposed, the insulating layer 23 being disposed so as to cover the semiconductor layer 27. The drain electrode 26 is electrically connected to the transparent electrode of the organic EL element 11 via a through electrode 28 that penetrates the overcoat layer 42 and electrically connects to the transparent electrode of the organic EL element 11 and the drain electrode 26.

The drive wiring 22 is provided on the surface of the substrate 5 on which the organic EL elements 11 are arranged. FIG. 2 shows the position of the electric circuit section 20 including the drive circuit 21 and the drive wiring 22 when the organic EL display device 1 of FIG. 1 is observed from the light emission surface 1a side, and is also a diagram showing the positions of the organic EL elements 11 and the substrate 5. In the example shown in FIG. 2, the substrate 5 is not shown, and the outline of the substrate 5 is shown by a dashed line with the reference symbol 5a. The drive wiring 22 extends in the first direction d1 and the second direction d2 in which the multiple organic EL elements 11 are arranged. The drive wiring 22 also extends at least partially between the organic EL elements 11.

When the active matrix system is employed, the electric circuit unit 20 includes, as the drive wiring 22, wiring that is connected to the transparent electrode and reflective electrode of each organic EL element 11 and is also connected to a current source or voltage source to apply a current or voltage to each organic EL element 11. The electric circuit unit 20 also includes, as the drive wiring 22, wiring that is connected to the drive circuit 21 to control the drive circuit 21 provided in each organic EL element 11, such as wiring connected to a transistor T.

The substrate 5 on which the electrical circuit section 20 is provided on one side is not particularly limited as long as it can support the electrical circuit section 20 and block outside air, but glass or a transparent polymer is preferable because of its good stability, durability, etc.

Next, the color filter 40 will be described. As shown in FIG. 1, the color filter 40 is disposed on the light emission side of the organic EL element 11. The color filter 40 also includes a pixel section 41 provided on the surface of the circuit layer 24 opposite the light emission side (the lower side shown in FIG. 1), and an overcoat layer 42 that covers the pixel section 41 from the side opposite the light emission side.

The color filter 40 has a first pixel portion 41a, a second pixel portion 41b, a third pixel portion 41c, and a fourth pixel portion 41d provided on the surface of the circuit layer 24 opposite to the light emission side as the pixel portion 41. Here, an example will be described in which the first pixel portion 41a is a white pixel portion that transmits white light as the first color, the second pixel portion 41b is a red pixel portion that selectively transmits red light as the second color, the third pixel portion 41c is a green pixel portion that selectively transmits green light as the third color, and the fourth pixel portion is a blue pixel portion that transmits blue light as the fourth color. Each pixel portion 41a, 41b, 41c, and 41d is formed by dispersing or dissolving a coloring material such as a pigment or dye of each color in a photosensitive resin, for example.

Examples of red colorants include perylene pigments, lake pigments, azo pigments, quinacridone pigments, anthraquinone pigments, anthracene pigments, and isoindoline pigments. These pigments may be used alone or in combination of two or more.

Examples of green colorants include phthalocyanine pigments such as halogen-substituted phthalocyanine pigments or halogen-substituted copper phthalocyanine pigments, triphenylmethane basic dyes, isoindoline pigments, isoindolinone pigments, etc. These pigments or dyes may be used alone or in combination of two or more.

Examples of blue colorants include copper phthalocyanine pigments, anthraquinone pigments, indanthrene pigments, indophenol pigments, cyanine pigments, and dioxazine pigments. These pigments may be used alone or in combination of two or more.

The white pixel portion is configured to appropriately transmit light in the visible light range over a wide range. For example, the white pixel portion is configured to have an average transmittance of 30% or more in the wavelength range of 380 to 780 nm in the transmission spectrum S _A of the white pixel portion. In this case, substantially white light is emitted from the white pixel portion toward the observer. The organic EL display device 1 may be configured with a pixel group having four sub-pixels of red, green, blue, and white, as shown in FIG. 1.

The colors of the pixel units 41 are not limited to the above-mentioned white, red, green, and blue, and may include pixel units 41 of other colors, such as yellow pixel units. As an example, the yellow pixel units have a higher average transmittance than other pixel units 41 other than the white pixel units, such as the red, green, and blue pixel units 41.

Also, a quantum dot film may be used as the color filter 40. In this case, the organic EL display device 1 becomes a quantum dot organic EL (QD-OLED) display device.

In the example shown in FIG. 1, the entire pixel section 41 is covered with the overcoat layer 42. This makes it possible to flatten the surface on which the organic EL element 11, which will be described later, is formed. It also makes it possible to protect the pixel section 41. The material constituting the overcoat layer 42 and the method for forming it can be appropriately selected from materials and methods that have been conventionally and generally used for overcoat layers.

Next, the element layer 14 will be described. A plurality of organic EL elements 11 are arranged inside the element layer 14. The organic EL elements 11 emit light to the outside of the organic EL display device 1. As an example, the organic EL elements 11 include at least a plurality of first elements 11a for emitting light of a first color and a plurality of second elements 11b for emitting light of a second color. The element layer 14 according to the present embodiment includes, as the organic EL elements 11, the first element 11a, the second element 11b, the third element 11c, and the fourth element 11d, which face the first pixel portion 41a, the second pixel portion 41b, the third pixel portion 41c, and the fourth pixel portion 41d, respectively, in a plan view of the substrate 5. For this reason, the light emitted by each element 11a, 11b, 11c, and 11d passes through each pixel portion 41a, 41b, 41c, and 41d before being emitted to the outside of the organic EL display device 1. As a result, light of the colors of the pixels 41a, 41b, 41c, and 41d is emitted to the outside of the organic EL display device 1.

In this embodiment, white light, red light, green light, and blue light are emitted to the outside of the organic EL display device 1 in accordance with the colors of the pixel portions 41a, 41b, 41c, and 41d. In this case, the first element 11a in particular serves as an element for emitting white light to the outside of the organic EL display device 1. The first element 11a emits white light through the first pixel portion 41a, which is a white pixel portion provided in the color filter 40.

Although not shown in the figure, each organic EL element 11 has a transparent electrode provided on the surface of the overcoat layer 42 opposite the light emission side, a light-emitting layer provided on the transparent electrode, and a reflective electrode provided on the light-emitting layer.

A transparent body is used for the transparent electrode. When the transparent electrode is used as the anode, a transparent body such as indium tin oxide (ITO) is used for the anode.

The light-emitting layer has a structure in which, for example, a hole injection layer, a hole transport layer, a light-emitting body, an electron transport layer, and an electron injection layer are laminated in this order from the transparent electrode side. Of these, layers other than the light-emitting body may be provided as necessary. In this embodiment, the first element 11a, the second element 11b, the third element 11c, and the fourth element 11d are all light-emitting bodies in the light-emitting layer that emit white light. In this case, the light-emitting body can be any material that contains a fluorescent organic substance configured to emit white light by applying a voltage, without any particular limitation. For example, the light-emitting body can be a quinolinol complex, an oxazole complex, various laser dyes, polyparaphenylenevinylene, etc.

The hole injection layer is intended to increase the efficiency of hole injection and is also a buffer layer to prevent leakage. The hole transport layer is intended to increase the efficiency of hole transport to the light emitter. The light emitter generates light when electrons and holes recombine with the application of an electric field. The electron transport layer is intended to increase the efficiency of electron transport to the light emitter. The electron injection layer is intended to increase the efficiency of electron injection.

The reflective electrode also functions as a reflective layer, and it is desirable for the reflective electrode to have as high a reflectance as possible in order to increase the light-emitting efficiency. In particular, when the reflective electrode is used as a cathode, it is preferable to use a material for the reflective electrode that is easy to inject electrons into and has excellent stability. For example, magnesium, silver, aluminum, an alloy of silver and lithium, an alloy of magnesium and silver, an alloy of aluminum and lithium, etc. are used as the reflective electrode.

In the example shown in FIG. 1, the element layer 14 further includes a protective layer 13. The protective layer 13 covers each organic EL element 11 from the side opposite the light emission side, thereby protecting them. The material of the protective layer 13 is a transparent material such as silicon nitride, silicon oxide, or silicon oxynitride.

Next, the transmission control panel 30 will be described. The transmission control panel 30 is a layer that suppresses reflection of external light incident on the organic EL display device 1 by the internal structure of the organic EL display device 1. As shown in FIG. 1, the transmission control panel 30 has an element light transmission region 30b and a transmission restriction region 30a having a visible light transmittance lower than that of the element light transmission region 30b. In the example shown in FIG. 1, the transmission control panel 30 is disposed on the light emission side of the element layer 14.

When the transmission control panel 30 is provided on the organic EL display device 1 as shown in FIG. 1, the element light transmission region 30b faces at least a part of the organic EL element 11. In addition, the transmission restriction region 30a faces at least a part of the electric circuit section 20.

In the example shown in FIG. 1, the element light transmission region 30b of the transmission control panel 30 is composed of a transmission layer 32. The transmission control panel 30 also has a transmission limiting layer 31 in the transmission limiting region 30a. The material of the transmission limiting layer 31 is a material that has a lower visible light transmittance than the material of the transmission layer 32 when compared at the same thickness. In the example shown in FIG. 1, the transmission layer 32 has a recess 32a in the transmission limiting region 30a that is recessed toward the side where the substrate 33 described later is disposed. The transmission limiting layer 31 is formed in the recess 32a. Therefore, the transmission limiting layer 31 and the transmission layer 32 are laminated in the transmission limiting region 30a. The transmission limiting region 30a may be composed of the transmission limiting layer 31.

The transmission control panel 30 may have transparency in the transmission limiting region 30a, or may not have transparency in the transmission limiting region 30a. The visible light transmittance in the transmission limiting region 30a of the transmission control panel 30 is, for example, 1% or more and 90% or less. Also, the visible light transmittance in the element light transmitting region 30b of the transmission control panel 30 is, for example, 70% or more and 100% or less.

Note that with respect to the transmission control panel 30, the visible light transmittance is the visible light transmittance in the direction dL in which the organic EL element 11 emits light (hereinafter also referred to as the emission direction dL). The visible light transmittance of the transmission control panel 30 and the like can be measured, for example, using a UV-3600 ultraviolet-visible light spectrophotometer manufactured by Shimadzu Corporation. Note that the visible light transmittance here refers to the average transmittance in the light wavelength range of 380 nm to 780 nm.

The material of the transmission limiting layer 31 is not particularly limited as long as it can reduce the visible light transmittance of the transmission limiting region 30a. For example, a composition in which colored light absorbing particles are dispersed in a photocurable resin such as urethane (meth)acrylate, polyester (meth)acrylate, epoxy (meth)acrylate, and butadiene (meth)acrylate can be mentioned. Instead of dispersing light absorbing particles, the entire light absorbing portion can be colored with a pigment or dye. When using light absorbing particles, light absorbing colored particles such as carbon black are preferably used, but the present invention is not limited to these, and colored particles that selectively absorb specific wavelengths according to the characteristics of the image light may be used. Specifically, organic fine particles colored with metal salts such as carbon black, graphite, black iron oxide, dyes, pigments, etc., and colored glass beads can be mentioned. In particular, colored organic fine particles are preferably used from the viewpoints of cost, quality, ease of availability, etc. The material of the transmission limiting layer 31 is a material that has a visible light transmittance of 1% to 90% when the thickness is 100 μm. The material of the transmission layer 32 is not particularly limited as long as it can increase the visible light transmittance of the element light transmission region 30b, but may be formed by curing, for example, an ultraviolet curing resin, an electron beam curing resin, or a thermosetting resin. When the transmission layer 32 is formed by curing an ultraviolet curing resin, the ultraviolet curing resin may contain an acrylic resin or an epoxy resin. As an example, the material of the transmission layer 32 is a material that has a visible light transmittance of 70% or more and 100% or less when the thickness is 50 μm.

Figure 3 is a diagram showing the positions of the drive wiring 22, the organic EL element 11, and the substrate 5, as well as the distribution range of the transmission limiting region 30a and the element light transmitting region 30b of the transmission control panel 30 when the organic EL display device 1 of Figure 1 is observed from the light emitting surface 1a side. In Figure 3, the dashed line with the reference symbol 20a indicates the outline of the electric circuit section 20. In the example shown in Figure 3, the element light transmitting region 30b is arranged in the first direction d1 and the second direction d2 and has a matrix pattern. In the examples shown in Figures 1 and 3, the element light transmitting region 30b faces the organic EL element 11. The electric circuit section 20 is not located in the part of the circuit layer 24 where the element light transmitting region 30b faces the organic EL element 11. And the transmission limiting region 30a faces the electric circuit section 20.

In the example shown in FIG. 1, the transmission control panel 30 further includes a substrate 33 that is disposed on the light exit side of the transmission layer 32. The material of the substrate 33 is not particularly limited as long as it is possible to form the transmission layer 32 and the transmission limiting layer 31 on the substrate 33, but is, for example, a film substrate made of a resin film.

The organic EL display device 1 according to the present embodiment may further include a barrier layer 4 arranged on the side of the element layer 14 opposite to the color filter 40, an alloy plate 2 arranged on the side of the barrier layer 4 opposite to the element layer 14, an adhesive layer 3 located between the barrier layer 4 and the alloy plate 2, and a hard coat 6 arranged on the light emission side of the transmission control panel 30. The adhesive layer 3 is a layer that bonds the alloy plate 2 and the barrier layer 4. The material of the adhesive layer 3 is not particularly limited as long as it can bond the alloy plate 2 and the barrier layer 4. The hard coat 6 is a layer for protecting the transmission control panel 30 and other parts of the organic EL display device 1 other than the hard coat 6. The hard coat 6 can be formed from a hard coat layer coating liquid containing, for example, a curable resin composition. Examples of the curable resin composition include a thermosetting resin composition and an ionizing radiation curable resin composition.

The effects of the organic EL display device 1 according to this embodiment will be described below. There is a concern that the electric circuit unit 20 may reflect external light incident on the organic EL display device 1. In particular, when the electric circuit unit 20 contains a material that highly reflects light, such as a metal material, the effect of reflection of external light by the electric circuit unit 20 becomes large.

In contrast, the organic EL display device 1 according to this embodiment includes a transmission control panel 30 having a transmission limiting region 30a that faces at least a portion of the electric circuit section 20. The transmission limiting region 30a can reduce the proportion of external light that reaches the portion of the electric circuit section 20 that faces the transmission limiting region 30a. The transmission limiting region 30a can also reduce the proportion of external light reflected in the electric circuit section 20 that is emitted to the outside of the organic EL display device 1. As a result, adverse effects caused by reflection of external light in the electric circuit section 20 can be suppressed.

In addition, in this embodiment, the transmission control panel 30 has an element light transmission region 30b. The element light transmission region 30b faces at least a portion of the multiple organic EL elements 11. Therefore, in the portion of the organic EL element 11 facing the element light transmission region 30b, the light emitted by the organic EL element 11 can be emitted to the outside of the organic EL display device 1 without being reduced by the transmission limiting region 30a. Therefore, the light output rate of the organic EL display device 1 can be improved compared to, for example, a case where a circular polarizing plate is used to reduce reflection of external light.

In particular, in a bottom-emission organic EL display device 1 in which the circuit layer 24 is disposed on the light-emitting side of the element layer 14, the distance between the electric circuit section 20 and the light-emitting surface 1a of the organic EL display device 1 tends to be small. It is also considered that when the distance between the electric circuit section 20 and the light-emitting surface 1a is small, more external light is likely to be reflected in the electric circuit section 20. In this regard, in the present embodiment, the transmission control panel 30 is disposed on the light-emitting side of the electric circuit section 20, and the transmission restriction region 30a faces at least a part of the electric circuit section 20. This makes it possible to suppress reflection of external light in the electric circuit section 20 even in a bottom-emission organic EL display device 1.

In addition, in this embodiment, as shown in FIG. 1, the circuit layer 24 is disposed on the light exit side of the color filter 40. Even in this case, the transmission control panel 30 is disposed on the light exit side of the circuit layer 24, so that reflection of external light in the electrical circuit section 20 can be suppressed.

In addition, in this embodiment, as shown in FIG. 1, the transmission limiting region 30a is arranged in a direction inclined with respect to the light exit surface 1a of the organic EL display device 1 with respect to the organic EL element 11 and the pixel unit 41 as references. Therefore, the transmission limiting region 30a can adjust the proportion of light emitted from the organic EL element 11 or the pixel unit 41 in a direction inclined with respect to the light exit surface 1a that is emitted to the outside of the organic EL display device 1. As a result, for example, when light of a specific color is easily emitted in an oblique direction, the transmission limiting region 30a can suppress the emission of the light of the specific color in an oblique direction. Therefore, when observing the screen from an oblique direction, it is possible to suppress the color balance on the screen from being lost due to the light of a specific color being strongly emitted in an oblique direction.

The method for manufacturing the transmission control panel 30 according to this embodiment is, for example, as follows. First, a sheet-like transmission layer 32 having a recess 32a is formed. The transmission layer 32 is formed, for example, on one side of a substrate 33. The recess 32a is formed so as to face at least a part of the electric circuit section 20 when the transmission control panel 30 is provided on the organic EL display device 1, in other words, when the transmission control panel 30 is incorporated into the organic EL display device 1.

Next, a transmission limiting layer 31 is formed in the recess 32a. This completes the manufacture of the transmission control panel 30 shown in FIG. 1.

Next, a method for manufacturing an organic EL display device 1 using the transmission control panel 30 manufactured by the above-mentioned method will be described. First, an electric circuit section 20 is formed on a substrate 5, and an insulating layer 23 covering the electric circuit section 20 is formed to form a circuit layer 24. Next, a pixel section 41 is formed on the circuit layer 24, and an overcoat layer 42 covering the pixel section 41 is formed to form a color filter 40. Next, a transparent electrode, a light-emitting layer, and a reflective electrode are sequentially provided on the color filter 40 to form a plurality of organic EL elements 11. Also, a protective layer 13 covering the organic EL elements 11 is formed. This forms an element layer 14. Next, a barrier layer 4 is formed on the element layer 14. Then, an alloy plate 2 is bonded to the barrier layer 4 via an adhesive layer 3. Also, a transmission control panel 30 is bonded to the surface of the substrate 5 opposite to the side on which the electric circuit section 20 is formed via an adhesive layer not shown. Also, a hard coat 6 is formed on the surface of the transmission control panel 30 opposite to the side bonded to the substrate 5. The organic EL display device 1 shown in FIG. 1 can be manufactured by the above.

Although one embodiment has been described using a specific example, this specific example is not intended to limit the embodiment. The embodiment described above can be implemented using various other specific examples, and various omissions, substitutions, changes, and additions can be made without departing from the spirit of the embodiment.

Below, an example of a modification will be described with reference to the drawings. In the following description and the drawings used in the following description, parts that can be configured similarly to the specific example described above will be designated by the same reference numerals as those used for the corresponding parts in the specific example described above, and duplicate descriptions will be omitted.

(First Modification)
Fig. 4 is a partial cross-sectional view showing a schematic configuration of an organic EL display device 1 in a first modified example. In the example shown in Fig. 4, the transmission limiting region 30a has a first region 30a1 facing at least a part of the electric circuit section 20 and a second region 30a2 facing a part of the organic EL element 11. In the example shown in Fig. 4, the organic EL element 11 has a part that does not face the electric circuit section 20. And the second region 30a2 faces the part of the organic EL element 11 that does not face the electric circuit section 20.

In the example shown in FIG. 4, the second region 30a2 faces the first element 11a. The organic EL display device 1 according to this modified example has a plurality of first elements 11a, and the second region 30a2 faces the plurality of first elements 11a.

In the example shown in FIG. 4, the transmission limiting layer 31 and the transmission layer 32 are disposed on the light exit side of the substrate 33.

The effect of the transmission limiting region 30a having the second region 30a2 will be described. There is a concern that the organic EL element 11, or the pixel portion 41 of the color filter 40 facing the organic EL element 11, may reflect external light incident on the organic EL display device 1. In response to this, the transmission limiting region 30a has the second region 30a2 facing the organic EL element 11, so that the external light incident on the organic EL display device 1 can be prevented from reaching the organic EL element 11 and the pixel portion 41. This makes it possible to reduce the amount of external light reflected by the organic EL element 11 or the pixel portion 41 and emitted to the outside of the organic EL display device 1.

In addition, when external light is reflected at the organic EL element 11 or the pixel unit 41, the external light passes through the second region 30a2 twice: once when it travels from the outside of the organic EL display device 1 toward the organic EL element 11 or the pixel unit 41, and once when it is reflected and travels toward the outside of the organic EL display device 1. On the other hand, light emitted by the organic EL element 11 passes through the second region 30a2 only once before being emitted to the outside of the organic EL display device 1. This makes it possible to efficiently reduce the amount of external light reflected at the organic EL element 11 and the pixel unit 41 and emitted to the outside of the organic EL display device 1, while improving the light output rate.

From the viewpoint of reducing the amount of external light reflected by the organic EL element 11 and the pixel unit 41 and emitted to the outside of the organic EL display device 1, it is preferable that the second region 30a2 faces the organic EL element 11 and the pixel unit 41 that are likely to reflect external light. For example, the organic EL element 11 configured to emit white light to the outside of the organic EL display device 1 is likely to reflect external light. For this reason, for example, when the first element 11a is configured to emit white light, it is preferable that the second region 30a2 faces a plurality of first elements 11a that emit white light. In particular, when the first pixel unit 41a facing the first element 11a is a white pixel unit, it is preferable that the second region 30a2 faces the first element 11a via the white pixel unit.

(Second Modification)
In addition, when the transmission limiting region 30a includes a first region 30a1 and a second region 30a2, the visible light transmittance of the first region 30a1 and the visible light transmittance of the second region 30a2 may be different. For example, the second region 30a2 may have a higher visible light transmittance than the first region 30a1. In this case, the first region 30a1 has a visible light transmittance of, for example, 0% or more and 5% or less, and the second region 30a2 has a visible light transmittance of, for example, 30% or more and 50% or less.

Figure 5 is a partial cross-sectional view showing a schematic configuration of an organic EL display device 1 in a second modified example. In the example shown in Figure 5, the transmission control panel 30 has a first transmission limiting layer 31a in the first region 30a1 and a second transmission limiting layer 31b in the second region 30a2 as the transmission limiting layer 31. In the second modified example, the material of the first transmission limiting layer 31a and the material of the second transmission limiting layer 31b are the same. The materials of the first transmission limiting layer 31a and the second transmission limiting layer 31b are materials that have a lower visible light transmittance than the material of the transmission layer 32 when compared at the same thickness. The thickness of the second transmission limiting layer 31b is smaller than the thickness of the first transmission limiting layer 31a. As a result, the second region 30a2 has a higher visible light transmittance than the first region 30a1.

The second region 30a2 has a higher visible light transmittance than the first region 30a1, so that the visible light transmittance of the second region 30a2 facing the organic EL element 11 can be made sufficiently large to improve the light output rate. In addition, the visible light transmittance of the first region 30a1 facing the electrical circuit section 20 can be made sufficiently low to suppress reflection of external light in the electrical circuit section 20.

The method for manufacturing the transmission control panel 30 shown in FIG. 5 is, for example, as follows. First, a transmission layer 32 having a recess 32a is formed on one side of the substrate 33. The recess 32a is formed to have a first bottom surface 32a1 and a second bottom surface 32a2. When the transmission control panel 30 is provided on the organic EL display device 1, the first bottom surface 32a1 faces at least a part of the electric circuit section 20. The second bottom surface 32a2 faces a part of the organic EL element 11. Here, the thickness of the region where the first bottom surface 32a1 of the transmission layer 32 is located is smaller than the thickness of the region where the second bottom surface 32a2 of the transmission layer 32 is located. Next, a transmission limiting layer 31 is formed in the recess 32a. In this manner, the transmission control panel 30 shown in FIG. 5 can be manufactured.

(Third Modification)
In addition, in the above-described embodiment and each modification, the transmission control panel 30 having the transmission limiting layer 31 in the transmission limiting region 30a has been described, but the form of the transmission control panel 30 is not limited to this. Fig. 6 is a plan view showing a part of the transmission control panel 30 of the organic EL display device 1 according to the third modification, as viewed in the emission direction dL.

In the example shown in FIG. 6, the transmission control panel 30 has a transmission portion 35 and a transmission limiting portion 34 having a visible light transmittance lower than that of the transmission portion 35 in the transmission limiting region 30a. The element light transmission region 30b of the transmission control panel 30 is also composed of the transmission portion 35. As an example, the dimension of the transmission limiting portion 34 in the emission direction dL is equal to the dimension of the transmission portion 35 in the emission direction dL. As shown in FIG. 6, by arranging the transmission limiting portion 34 in a part of the transmission limiting region 30a, the average visible light transmittance in the transmission limiting region 30a is lower than the average visible light transmittance in the element light transmission region 30b.

In the example shown in FIG. 6, the transmission control panel 30 has a transmission section 35 and a transmission limiting section 34 in the first region 30a1 and the second region 30a2, respectively. When viewed in the emission direction dL, the ratio of the area of the transmission limiting section 34 in the first region 30a1 to the area of the first region 30a1 is greater than the ratio of the area of the transmission limiting section 34 in the second region 30a2 to the area of the second region 30a2. As a result, the average visible light transmittance in the second region 30a2 is higher than the average visible light transmittance in the first region 30a1.

When the first region 30a1 and the second region 30a2 each have a transmission portion 35 and a transmission limiting portion 34, the visible light transmittance of the first region 30a1 and the second region 30a2 is determined as follows. The visible light transmittance of the first region 30a1 is the sum of the visible light transmittance of the transmission portion 35 multiplied by the proportion of the transmission portion 35 in the first region 30a1 and the visible light transmittance of the transmission limiting portion 34 multiplied by the proportion of the transmission limiting portion 34 in the first region 30a1. The visible light transmittance of the second region 30a2 is the sum of the visible light transmittance of the transmission portion 35 multiplied by the proportion of the transmission portion 35 in the second region 30a2 and the visible light transmittance of the transmission limiting portion 34 multiplied by the proportion of the transmission limiting portion 34 in the second region 30a2.

In the example shown in FIG. 6, the transmissive portion 35 has a plurality of openings 35b in the transmissive limiting region 30a. The openings 35b penetrate the transmissive portion 35 in the light emission direction of the organic EL element 11. In the example shown in FIG. 6, the transmissive portion 35 has a mesh-like shape in which the plurality of openings 35b are arranged. The transmissive portion 34 is formed within the openings 35b.

The material of the permeation limiting portion 34 is, for example, the same as the material of the permeation limiting layer 31 described above. The material of the permeation portion 35 is, for example, the same as the material of the permeation layer 32 described above.

The manufacturing method of the transmission control panel 30 shown in FIG. 6 is, for example, as follows. First, a sheet-like transmission section 35 having an opening area 35a including a plurality of openings 35b is formed. The transmission section 35 is formed, for example, on one side of the substrate 33. The opening area 35a is formed so as to face at least a part of the electric circuit section 20 when the transmission control panel 30 is provided on the organic EL display device 1. The opening area 35a has a first opening area 35a1 that faces at least a part of the electric circuit section 20 when the transmission control panel 30 is provided on the organic EL display device 1, and a second opening area 35a2 that faces a part of the organic EL element 11. Then, when the transmission control panel 30 is incorporated into the organic EL display device 1, the following relationship is established. When viewed in the emission direction dL, the ratio of the area of the openings 35b in the first opening area 35a1 to the area of the first opening area 35a1 is greater than the ratio of the area of the openings 35b in the second opening area 35a2 to the area of the second opening area 35a2.

Next, a transmission limiting section 34 having a visible light transmittance lower than that of the transmission section 35 is formed in the opening 35b. In this manner, the transmission control panel 30 shown in FIG. 6 can be manufactured.

(Fourth Modification)
In the above-described embodiment and each modified example, the organic EL display device 1 is a so-called bottom emission type organic EL display device in which the circuit layer 24 including the driving element such as the transistor T is disposed on the light emission side of the element layer 14. However, the form of the organic EL display device 1 is not limited to this. FIG. 7 is a partial cross-sectional view showing a schematic configuration of the organic EL display device 1 in the second modified example. In the example shown in FIG. 7, the organic EL display device 1 is a so-called top emission type organic EL display device in which the element layer 14 is disposed on the light emission side of the circuit layer 24. In the example shown in FIG. 7, the electric circuit section 20, the organic EL element 11, and the transmission control panel 30 are arranged in this order toward the outside where the light from the organic EL element 11 is emitted. Although not shown, the electric circuit section 20, the transmission control panel 30, and the organic EL element 11 may be arranged in this order toward the outside where the light from the organic EL element 11 is emitted.

In addition, in the above-mentioned embodiment and each modified example, an example has been described in which the organic EL display device 1 employs an active matrix method for driving each organic EL element 11. However, the form of the organic EL display device 1 is not limited to this. For example, the organic EL display device 1 may be a passive matrix organic EL display device in which the transparent electrode and the reflective electrode of the organic EL element 11 are directly connected to the vertical scanning line and the horizontal scanning line, respectively, and driven without providing a driving element such as a transistor T for driving the organic EL element 11. In this case, the electric circuit unit 20 includes, for example, the vertical scanning line and the horizontal scanning line.

In the above-mentioned embodiment and each modified example, the organic EL display device 1 emits light of each color by the organic EL element 11 using a white-emitting material as the light-emitting body of the light-emitting layer and the color filter 40. However, the form of the organic EL display device 1 is not limited to this. For example, a color-coded method or a color conversion method may be adopted as a method for emitting light of each color. Even if another method is adopted as a method for emitting light of each color, the transmission control panel 30 can suppress reflection of external light in the electric circuit section 20. In addition, the transmission control panel 30 having the first region 30a1 and the second region 30a2 in particular can suppress reflection of external light in the organic EL element 11. In addition, when the organic EL display device 1 includes the color filter 40, reflection of external light in the pixel section 41 can be suppressed. In this way, the light output rate can be improved while suppressing reflection of external light in the organic EL element 11 and the pixel section 41. In addition, when the color-coded method is adopted, the organic EL display device 1 does not need to include the color filter 40.

REFERENCE SIGNS LIST 1 Organic EL display device 5 Substrate 11 Organic EL element 13 Protective layer 14 Element layer 20 Electric circuit section 21 Drive circuit 22 Drive wiring 23 Insulating layer 24 Circuit layer 30 Transmission control panel 30a Transmission limiting region 30a1 First region 30a2 Second region 30b Element light transmission region 31 Transmission limiting layer 31a First transmission limiting layer 31b Second transmission limiting layer 32 Transmission layer 33 Base material 34 Transmission limiting section 35 Transmission section 35a Opening region 35b Opening T Transistor

Claims (15)

A plurality of organic EL elements;
an electric circuit section used to drive the organic EL element;
a transmission control panel disposed on the light emission side of the organic EL element from the electric circuit unit,
the transmission control panel has an element light transmission region facing at least a part of the organic EL element, and a transmission limiting region facing at least a part of the electric circuit unit and having a visible light transmittance lower than that of the element light transmission region ,
the electric circuit section, the organic EL element, and the transmission control panel are arranged in this order toward the outside where the light from the organic EL element is emitted . A plurality of organic EL elements;
an electric circuit section used to drive the organic EL element;
a transmission control panel disposed on the light emission side of the organic EL element from the electric circuit unit,
the transmission control panel has an element light transmission region facing at least a part of the organic EL element, and a transmission limiting region facing at least a part of the electric circuit unit and having a visible light transmittance lower than that of the element light transmission region ,
the transmission limiting region has a first region facing at least a part of the electric circuit section, and a second region facing a part of the organic EL element, the organic EL display device. The organic EL display device according to claim 2 , wherein the organic EL element, the electric circuit section, and the transmission control panel are arranged in this order toward an outside where light from the organic EL element is emitted. the plurality of organic EL elements include at least a plurality of first elements for emitting light of a first color and a plurality of second elements for emitting light of a second color;
The organic electroluminescence display device according to claim 2 , wherein the second region faces a plurality of the first elements. The organic electroluminescence display device according to claim 4 , wherein the first element emits white light. The organic electroluminescence display device according to claim 5 , wherein the first element emits white light via a white pixel portion provided in a color filter, and the second region faces the first element via the white pixel portion. The organic electroluminescence display device according to claim 2 , wherein the second region has a visible light transmittance higher than that of the first region. The first region has a visible light transmittance of 0% or more and 5% or less,
The organic electroluminescence display device according to claim 7 , wherein the second region has a visible light transmittance of 30% or more and 50% or less. 9. The organic electroluminescence display device according to claim 2 , wherein the transmission control panel has a first transmission limiting layer in the first region and a second transmission limiting layer in the second region, the second transmission limiting layer being thinner than the first transmission limiting layer. the transmission control panel has a transmission portion and a transmission limiting portion having a visible light transmittance lower than that of the transmission portion in the first region and the second region, respectively;
10. The organic EL display device according to claim 2, wherein, when viewed in a direction in which light is emitted from the organic EL element, a ratio of an area of the transmission limiting portion in the first region to an area of the first region is greater than a ratio of an area of the transmission limiting portion in the second region to an area of the second region. A transmission control panel provided in an organic EL display device including a plurality of organic EL elements and an electric circuit unit used to drive the organic EL elements,
an element light transmission region facing at least a part of the organic EL element when the transmission control panel is provided in the organic EL display device; and a transmission limiting region facing at least a part of the electric circuit unit when the transmission control panel is provided in the organic EL display device and having a visible light transmittance lower than that of the element light transmission region ,
The transmission limiting region has a first region facing at least a part of the electric circuit section, and a second region facing a part of the organic EL element. A method for manufacturing a transmission control panel provided in an organic EL display device including a plurality of organic EL elements and an electric circuit unit used to drive the organic EL elements, comprising the steps of:
forming a sheet-like transmissive layer having a recess that faces at least a part of the electric circuit unit when the transmission control panel is provided on the organic EL display device;
forming a permeation limiting layer in the recess;
A method for manufacturing a transmission control panel, wherein the material of the transmission limiting layer has a lower visible light transmittance than the material of the transmission layer when compared at the same thickness. the recess has a first bottom surface facing at least a part of the electric circuit unit when the transmission control panel is provided on the organic EL display device, and a second bottom surface facing a part of the organic EL element when the transmission control panel is provided on the organic EL display device,
The method for manufacturing a transmission control panel according to claim 12 , wherein a thickness of the transmissive layer in a region where the first bottom surface is located is smaller than a thickness of the transmissive layer in a region where the second bottom surface is located. A method for manufacturing a transmission control panel provided in an organic EL display device including a plurality of organic EL elements and an electric circuit unit used to drive the organic EL elements, comprising the steps of:
forming a sheet-like transmissive portion having an opening region including a plurality of openings and facing at least a portion of the electric circuit portion when the transmission control panel is provided in the organic EL display device;
and forming a transmission limiting portion within the opening, the transmission portion having a visible light transmittance lower than that of the transmission portion. the opening region has a first opening region facing at least a part of the electric circuit unit when the transmission control panel is provided in the organic EL display device, and a second opening region facing a part of the organic EL element when the transmission control panel is provided in the organic EL display device,
15. The method for manufacturing a transmission control panel as described in claim 14, wherein, when viewed in a direction in which light is emitted from the organic EL element, a ratio of an area of the opening in the first opening region to an area of the first opening region is greater than a ratio of an area of the opening in the second opening region to an area of the second opening region.