JP7588951B2 - Organic electroluminescent display device - Google Patents

Description

This disclosure relates to an organic electroluminescence display device.

Organic EL display devices using organic electroluminescence (EL) elements have advantages such as high visibility due to self-luminance, being all-solid-state display devices unlike liquid crystal display devices, being less susceptible to temperature changes, and having a wide viewing angle, and therefore have been increasingly put to practical use as full-color display devices in recent years. Among organic EL display devices used in smartphones and the like, there are known ones that are equipped with proximity sensors including light-receiving elements and light-emitting elements on the same plane as the organic EL elements or on a different plane.

JP 2019-33071 A

In an organic EL display device, it is sometimes required to widen the display area in which images are displayed, particularly in a smartphone or the like in which the display area is limited, to expand the display area to the entire screen. Smartphones and the like are sometimes equipped with imaging elements and proximity sensors, but if the organic EL display device is not translucent, it is difficult to expand the display area to the entire screen. In general, in an organic EL display device, since it is necessary to extract light generated in the organic light-emitting layer in a specific direction, a metal material with poor light transmissivity may be used as the cathode electrode. Therefore, it is difficult to use the entire screen constituted by the organic EL display device as the display area. In this regard, for example, a transparent area that can transmit light is formed between subpixels in the organic EL element, and light (infrared rays, etc.) emitted from the light-emitting element through this transparent area is reflected by an object and received by the light-receiving element through the adjacent transparent area, or imaging is possible through the transparent area, so that the entire screen can be constituted by the organic EL display device and the display area in which images are displayed can be expanded.

On the other hand, there is also a demand for increasing the pixel density in organic EL display devices in order to enable the display of high-definition images. However, increasing the pixel density tends to narrow the transmissive areas located between the subpixels, which may result in a deterioration in transmissive performance. In order to avoid lowering the pixel density and narrowing the transmissive areas, it is possible to reduce the size of the organic compound layer (organic light-emitting layer) in the organic EL element, but this may result in a decrease in the brightness of the organic EL display device.

In view of the above problems, an object of the present disclosure is to provide an organic electroluminescence display device with excellent light transmission performance.

A first aspect of the present disclosure is an organic electroluminescence display device comprising: a substrate having a first surface and a second surface opposite to the first surface; a plurality of first electrodes arranged in a matrix on the first surface of the substrate; a plurality of organic compound layers respectively positioned on the plurality of first electrodes; a second electrode positioned on the plurality of organic compound layers and having a plurality of openings positioned between adjacent organic compound layers in a planar view from the first surface side toward the second surface side; and a lens provided in a position opposite at least some of the openings, wherein in a planar view from the second electrode side toward the first electrode side or from the first electrode side toward the second electrode side, the lens is provided in a position that does not overlap the first electrode and is positioned opposite the openings on the opposite side of the substrate with respect to the second electrode .

As a second aspect of the present disclosure, in the first aspect, the lens may be provided at a position facing the opening on the opposite side of the substrate with respect to the second electrode.
As a third aspect of the present disclosure, in the first aspect, the lens may be provided at a position facing the opening on the substrate side with respect to the second electrode.
As a fourth aspect of the present disclosure, in the first aspect above, the lens may include a first lens provided at a position facing the opening on the side opposite the substrate with respect to the second electrode, and a second lens provided at a position facing the opening on the substrate side with respect to the second electrode.

As a fifth aspect of the present disclosure, in each of the first to fourth aspects, the organic compound layer may include an organic light-emitting layer.
As a sixth aspect of the present disclosure, in each of the first to fifth aspects, the lens may include a cylindrical lens.
As a seventh aspect of the present disclosure, in each of the first to fifth aspects, the lens may include a spherical lens.

According to the present disclosure, an organic electroluminescence display device with excellent transmission performance can be provided.

FIG. 1 is a cross-sectional view showing a schematic configuration of a first embodiment of an organic electroluminescence (EL) display device according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view showing a schematic configuration of a second embodiment of an organic electroluminescence (EL) display device according to an embodiment of the present disclosure. FIG. 3 is a cross-sectional view showing a schematic configuration of a third embodiment of an organic electroluminescence (EL) display device according to an embodiment of the present disclosure. FIG. 4 is a cross-sectional view showing a schematic configuration of a fourth embodiment of an organic electroluminescence (EL) display device according to an embodiment of the present disclosure. FIG. 5 is a cross-sectional view showing a schematic configuration of a fifth embodiment of an organic electroluminescence (EL) display device according to an embodiment of the present disclosure. FIG. 6 is a plan view showing an example of the positional relationship between a first electrode, an organic compound layer, a second electrode, and a lens in an embodiment of the present disclosure. FIG. 7 is a plan view showing another example of the positional relationship between the first electrode, the organic compound layer, the second electrode, and the lens in the embodiment of the present disclosure. FIG. 8 is a cross-sectional view illustrating a state in which light passes through an opening via a lens in an organic electroluminescence (EL) display device according to an embodiment of the present disclosure. FIG. 9 is a cross-sectional view illustrating the positional relationship between a first electrode, an organic compound layer, and a lens in an embodiment of the present disclosure. FIG. 10A is a cross-sectional view illustrating a step of a method for manufacturing an organic electroluminescence (EL) display device according to an embodiment of the present disclosure. FIG. 10B is a cross-sectional view showing a step in a method for manufacturing an organic electroluminescence (EL) display device according to an embodiment of the present disclosure, the step following that shown in FIG. 10A. FIG. 10C is a cross-sectional view showing a step in a method for manufacturing an organic electroluminescence (EL) display device according to an embodiment of the present disclosure, the step following that shown in FIG. 10B. FIG. 10D is a cross-sectional view showing a step in a method for manufacturing an organic electroluminescence (EL) display device according to an embodiment of the present disclosure, the step following that shown in FIG. 10C. FIG. 11A is a cutaway end view illustrating a step in making a lens in one embodiment of the present disclosure. FIG. 11B is a cutaway end view showing a step in making a lens in one embodiment of the present disclosure, the step following FIG. 11A. FIG. 11C is a cutaway end view showing a step in making a lens in one embodiment of the present disclosure, the step following FIG. 11B. FIG. 12A is a cutaway end view showing a step in making a lens in one embodiment of the present disclosure. FIG. 12B is a cutaway end view showing a step in making a lens in one embodiment of the present disclosure, the step following FIG. 12A. FIG. 13A is a cutaway end view illustrating one step in making a lens in one embodiment of the present disclosure. FIG. 13B is a cutaway end view showing a step in making a lens in one embodiment of the present disclosure, the step following FIG. 13A. FIG. 14A is a cutaway end view showing a step in making a lens in one embodiment of the present disclosure. FIG. 14B is a cutaway end view showing a step in making a lens in one embodiment of the present disclosure, the step following FIG. 14A.

In this specification and drawings, unless otherwise specified, terms such as "plate," "sheet," and "film" are not distinguished from each other based only on the difference in name. For example, "plate" is a concept that includes members that can be called sheets and films. Furthermore, "surface (sheet surface, film surface)" refers to a surface that coincides with the planar direction of the target plate-like member (sheet-like member, film-like member) when the target plate-like (sheet-like, film-like) member is viewed overall and in a global perspective. Furthermore, the normal direction used for a plate-like (sheet-like, film-like) member refers to the normal direction to the surface (sheet surface, film surface) of the member. Furthermore, terms such as "parallel" and "orthogonal," and values of lengths and angles, which specify the shape and geometric conditions and their degrees, as used in this specification, are interpreted to include the range in which similar functions can be expected without being bound by strict meanings.

Unless otherwise specified, in this specification and drawings, terms such as "parallel" and "orthogonal" that specify shapes and geometric conditions and their degrees, as well as values of lengths and angles, are to be interpreted without being bound by strict meanings, but rather to include the range within which similar functions can be expected.

In this specification and drawings, when a certain configuration such as a certain member or a certain region is described as being "on (or under)", "above (or below)" or "above (or below)" another configuration such as another member or another region, unless otherwise specified, this is to be interpreted as including not only the case where a certain configuration is in direct contact with the other configuration, but also the case where another configuration is included between the certain configuration and the other configuration. Furthermore, unless otherwise specified, the words "above" (or "upper side" or "upper") or "below" (or "lower side" or "lower") may be used in the description, but the up-down direction may be reversed.

In this specification and drawings, unless otherwise specified, identical parts or parts having similar functions are given the same or similar symbols, and repeated explanations may be omitted. In addition, the dimensional ratios of the drawings may differ from the actual ratios for the convenience of explanation, and some components may be omitted from the drawings.

Unless otherwise specified in this specification and drawings, the present invention may be combined with other embodiments and modified examples to the extent that no contradictions arise. In addition, other embodiments may be combined with each other, or other embodiments may be combined with modified examples to the extent that no contradictions arise. In addition, modified examples may be combined with each other to the extent that no contradictions arise.

Unless otherwise specified in this specification and drawings, when multiple steps are disclosed in a method such as a manufacturing method, other steps that are not disclosed may be performed between the disclosed steps. In addition, the order of the disclosed steps is arbitrary to the extent that no contradiction occurs.

In this specification and drawings, unless otherwise specified, a numerical range expressed by the symbol "~" includes the numerical values before and after the symbol. For example, the numerical range defined by the expression "34 to 38 mass%" is the same as the numerical range defined by the expression "34 mass% or more and 38 mass% or less."

Embodiments of the present disclosure will be described with reference to the drawings. Note that the embodiments described below are examples of embodiments of the present disclosure, and the present disclosure should not be interpreted as being limited to only these embodiments.

FIG. 1 is a cross-sectional end view showing a schematic configuration of a first aspect of an organic electroluminescence (EL) display device according to this embodiment, FIG. 2 is a cross-sectional end view showing a schematic configuration of a second aspect of an organic electroluminescence (EL) display device according to this embodiment, FIG. 3 is a cross-sectional end view showing a schematic configuration of a third aspect of an organic electroluminescence (EL) display device according to this embodiment, FIG. 4 is a cross-sectional end view showing a schematic configuration of a fourth aspect of an organic electroluminescence (EL) display device according to this embodiment, and FIG. 5 is a cross-sectional end view showing a schematic configuration of a fifth aspect of an organic electroluminescence (EL) display device according to this embodiment.

As shown in Figures 1 to 5, the organic EL display device 10 may be configured as a laminate including, in this order, a substrate 11 having a TFT element (not shown), a first interlayer insulating film 12, a first electrode 13, an organic compound layer 14, a second electrode 15, and a second interlayer insulating film 16. In this embodiment, the organic EL display device 10 may be a bottom emission type in which light generated in the organic compound layer 14 is extracted from the substrate 11 side, or a top emission type in which light generated in the organic compound layer 14 is extracted from the second interlayer insulating film 16 side.

The substrate 11 is a transparent substrate having a first surface 11A and a second surface 11B facing the first surface 11A, and, for example, a TFT element may be provided on the first surface 11A side. As the substrate 11, for example, a glass substrate such as an alkali glass, quartz glass, borosilicate glass, or alkali-free glass; a sapphire substrate; or a resin substrate such as an acrylic resin, a polyester resin, a polycarbonate resin, a polyolefin resin, or a cycloolefin polymer may be used.

The size (size in a plan view) and thickness of the substrate 11 can be set appropriately taking into consideration the size of the organic EL display device 10 according to this embodiment and the ease of handling of the substrate 11, and are not particularly limited.

Either the first electrode 13 or the second electrode 15 may constitute an anode (anode electrode), and the other of the first electrode 13 and the second electrode 15 may constitute a cathode (cathode electrode). For example, the first electrode 13 may be an anode electrode, and the second electrode 15 may be a cathode electrode. Of course, the first electrode 13 may be a cathode electrode, and the second electrode 15 may be an anode electrode. The organic compound layer 14 sandwiched between the first electrode 13 and the second electrode 15 may be a laminate including a hole injection layer, a hole transport layer, an organic light-emitting layer, an electron transport layer, and an electron injection layer in this order from the first electrode 13 side to the second electrode 15 side. When a driving voltage is applied from the first electrode 13 side, holes are injected from the first electrode 13 into the organic light-emitting layer, and electrons are injected from the second electrode 15 into the organic light-emitting layer. The energy generated by the combination of holes and electrons injected into the organic light-emitting layer excites the organic material that makes up the organic light-emitting layer, and the organic light-emitting layer emits light when it returns from the excited state to the ground state.

The first electrode 13 may be made of a transparent conductive material that transmits light relatively easily, and the second electrode 15 may be made of a conductive material that transmits light relatively little. Of course, the second electrode 15 may be made of a conductive material that transmits light relatively easily, and the first electrode 13 may be made of a conductive material that transmits light relatively little. Examples of transparent conductive materials include ITO (Indium Tin Oxide), InZnO (Indium Zinc Oxide), AlZnO (Aluminum Zinc Oxide), and AlTO (Aluminum Tin Oxide). Examples of conductive materials that transmit light relatively little include metal materials such as Mg, Ag, Mg/Ag (magnesium silver alloy), Al, and Ca. These metal materials have a relatively low work function and are thought to be able to efficiently inject electrons into the electron injection layer of the organic compound layer 14. In the present embodiment, "transparent" can be defined by the transmittance (%) of light, and may be defined by the transmittance (%) of light of a wavelength corresponding to the application or the like for which transparency is required or desired. For example, in a case where transparency is required or desired in order to provide a proximity sensor including a light-emitting element that emits near-infrared light and a light-receiving element that receives the near-infrared light in the organic EL display device 10, "transparent" can be defined by the transmittance (%) of light of a wavelength of 700 nm to 1400 nm. In addition, in a case where transparency is required or desired in order to provide an imaging element in the organic EL display device 10, "transparent" can be defined by the transmittance (%) of light of a wavelength of 400 nm to 700 nm. Specifically, "transparent" means that the transmittance of light in a wavelength range corresponding to each application or the like is 30% or more, and preferably the transmittance of light in a wavelength range corresponding to each application or the like is 80% or more. Therefore, for example, the transmittance of light in a wavelength range corresponding to each application or the like in a conductive material that is relatively difficult to transmit light is less than 30%, and preferably the transmittance of light in a wavelength range corresponding to each application or the like is 5% or less. The light transmittance for each wavelength range can be measured, for example, using a spectroscopic haze meter (product name: HSP-150VIR, manufactured by Murakami Color Research Laboratory).

The first electrode 13 may be provided at a position corresponding to the organic compound layer 14. That is, a plurality of first electrodes 13 are provided in a matrix on the first interlayer insulating film 12. The term "matrix" means that a predetermined member is arranged in parallel at a predetermined pitch in one direction on a predetermined plane and in a direction perpendicular to the one direction. For example, "a plurality of first electrodes 13 are provided in a matrix on the first interlayer insulating film 12" means that the first electrodes 13 are arranged in parallel at a predetermined pitch on the first interlayer insulating film 12 in one direction (e.g., the first direction D1 shown in FIG. 6 and FIG. 7) and in a direction perpendicular to the one direction (e.g., the second direction D2 shown in FIG. 6 and FIG. 7), and the pitch of the first electrodes 13 arranged in parallel in the first direction D1 and the pitch of the first electrodes 13 arranged in parallel in the second direction may be the same or different.

The planar shape of the first electrode 13 may be, for example, approximately circular, elliptical, polygonal, striped, etc. The term "approximate" is a concept that includes manufacturing errors and the like during the formation of the first electrode 13. For example, in the case of an approximately circular shape, the range of the short diameter when the long diameter is 1 may be determined by the values of a first group including 0.80, 0.83, and 0.86, and the values of a second group including 0.89, 0.92, and 0.95. For example, the lower limit of the range of the short diameter may be determined by any one of the values included in the first group described above. For example, the lower limit of the range of the short diameter may be 0.80 or more, 0.83 or more, or 0.86 or more. The upper limit of the range of the short diameter may be determined by any one of the values included in the second group described above. For example, the upper limit of the range of the short diameter may be 0.89 or less, 0.92 or less, or 0.95 or less. The range of the minor axis may be determined by a combination of any one of the values included in the first group described above and any one of the values included in the second group described above, and may be, for example, 0.80 to 0.95, 0.83 to 0.92, or 0.86 to 0.89. The range of the minor axis may also be determined by a combination of any two of the values included in the first group described above, and may be, for example, 0.80 to 0.86, or 0.83 to 0.86. The range of the minor axis may also be determined by a combination of any two of the values included in the second group described above, and may be, for example, 0.89 to 0.95, or 0.92 to 0.95.

In a plan view from the second interlayer insulating film 16 toward the substrate 11, the first electrode 13 may be surrounded by an insulating film 17 made of, for example, polyimide. That is, the insulating film 17 may be positioned so as to overlap the outer periphery of the first electrode 13 in the plan view.

The second electrode 15 is a common electrode for injecting electrons into each organic compound layer 14. The second electrode 15 has an opening 151 located between adjacent organic compound layers 14 in a plan view of the first surface 11A side of the substrate 11. As shown in FIGS. 6 and 7, the opening 151 may be located approximately in the center of a region surrounded by four organic compound layers 14 (subpixels) (a rectangular region indicated by a dashed line in FIGS. 6 and 7). When the second electrode 15 is made of a conductive material that is relatively difficult to transmit light, the presence of this opening 151 makes it easier for light traveling in the thickness direction of the organic EL display device 10 to transmit through it.

The opening 151 of the second electrode 15 may be substantially circular (see FIG. 6 and FIG. 7), oval, polygonal, or the like. By making the opening area (total opening area) of the opening 151 as large as possible, the transmission performance of the organic EL display device 10 can be improved. It is considered that the larger the opening area (total opening area) of the opening 151 is, the higher the electrical resistance of the second electrode 15 tends to be, and the higher the power consumption tends to be. In other words, it can be said that there is a trade-off between the transmission performance and the power consumption in the organic EL display device 10. In order to increase the opening area (total opening area) of the opening 151, it is possible to reduce the size of the organic compound layer 14 or increase the pitch of the adjacent organic compound layers 14. However, it is presumed that the brightness of the organic EL display device will decrease if the size of the organic compound layer 14 is reduced. It is also presumed that the image displayed on the organic EL display device will become rough if the pitch of the adjacent organic compound layers 14 is increased. In the organic EL display device 10 according to this embodiment, as described below, the lens 18 is provided, which can improve the transmission performance while suppressing an increase in power consumption. In addition, the lens 18 eliminates the need to reduce the size of the organic compound layer 14 or increase the pitch between adjacent organic compound layers 14 in order to improve the transmittance, which can increase the brightness of the organic EL display device 10 and increase the pixel density, thereby enabling the display of high-definition images.

The size of the opening 151 is not particularly limited, as long as it is large enough that the first electrode 13 is covered by the second electrode 15 in a plan view from the second interlayer insulating film 16 toward the substrate 11, and the resistance of the second electrode 15 does not become too large, thereby preventing excessive power consumption.

The organic compound layer 14 disposed between a pair of the first electrode 13 and the second electrode 15 may include a red organic compound layer 14R, a green organic compound layer 14G, and a blue organic compound layer 14B, each of which constitutes a unit pixel of the organic EL display device, or may include a white organic compound layer. The red organic compound layer 14R, the green organic compound layer 14G, and the blue organic compound layer 14B emit red light, green light, and blue light, respectively. The white organic compound layer emits white light. When the organic compound layer 14 includes a white organic compound layer, a color filter may be provided if the organic EL display device 10 displays images in color. Note that even when the organic compound layer 14 includes a red organic compound layer 14R, a green organic compound layer 14G, and a blue organic compound layer 14B, a color filter having a colored layer corresponding to each of the organic compound layers 14R, 14G, and 14B may be provided. The materials constituting the red organic compound layer 14R, the green organic compound layer 14G, and the blue organic compound layer 14B are not particularly limited as long as they contain a fluorescent organic compound that emits light of a desired color when a predetermined voltage is applied. Examples of the fluorescent organic compound include quinolinol complexes, oxazole complexes, various laser dyes, polyparaphenylenevinylene, and the like. The organic compound layer 14 is provided on the first electrode 13 that is arranged in a matrix on the first interlayer insulating film 12, so the organic compound layer 14 is also provided in a matrix.

The TFT element can control the voltage selectively applied to the red organic compound layer 14R, the green organic compound layer 14G, and the blue organic compound layer 14B from a pair of the first electrode 13 and the second electrode 15. As the TFT element, a known type of TFT, such as a polycrystalline silicon TFT, can be used. The TFT element is connected to the first electrode 13 via a wiring electrode that penetrates the first interlayer insulating film 12 formed on the TFT element.

As a material constituting the first interlayer insulating film 12 and the second interlayer insulating film 16, for example, a material having insulating properties can be used. As a material constituting the first interlayer insulating film 12 and the second interlayer insulating film 16, for example, inorganic materials such as silicon oxide, photoresist, resin materials such as acrylic resin, etc. can be used.

An insulating film having a thickness of about 0.2 nm to 3.0 nm may be provided between the second electrode 15 and the organic compound layer 14 (electron injection layer). It is presumed that the provision of this insulating film facilitates the injection of electrons from the second electrode 15 to the organic compound layer 14 (electron injection layer) by the tunnel effect. Examples of materials constituting the insulating film include lithium fluoride (LiF), alumina (Al ₂ O ₃ ), and polymethyl methacrylate (PMMA). In addition, when the insulating film is provided between the second electrode 15 and the organic compound layer 14, the organic compound layer 14 may be a laminate including a hole injection layer, a hole transport layer, an organic light-emitting layer, and an electron transport layer in this order from the first electrode 13 side to the second electrode 15 side. In this case, it is considered that the insulating film can function as an electron injection layer.

In the organic EL display device 10 according to this embodiment, a lens 18 may be provided at a position facing the opening 151 of the second electrode 15. In general, in an organic EL display device having a second electrode (cathode electrode) with an opening, most of the light traveling in the thickness direction (for example, in the organic EL display device 10 shown in FIG. 1, the direction from the substrate 11 to the second interlayer insulating film 16 or the reverse direction) is difficult to transmit through the organic EL display device. This is because, although light (for example, external light) that transmits through the organic EL display device is considered to pass through the opening of the second electrode, when the second electrode is made of a material that is relatively difficult to transmit light (for example, a metal material such as magnesium, silver, or magnesium-silver alloy), it is presumed that much of the light is reflected on the surface of the second electrode. As a result, there is a problem that it is difficult to improve the transmittance of the organic EL display device. In the organic EL display device 10 according to this embodiment, the lens 18 is provided at a position facing the opening 151 of the second electrode 15. This allows light traveling in a direction that would cause it to be reflected by the surface of the second electrode 15 if the lens 18 were not provided to be focused toward the opening 151 via the lens 18 and to easily pass through the opening 151, thereby improving the transmittance (see FIG. 8).

The lens 18 may be provided at a position facing all the openings 151 of the second electrode 15, or at a position facing some of the openings 151. When the organic EL display device 10 according to the present embodiment is a so-called transmissive organic EL display device 10 in which the back side is visible when the observer side of the organic EL display device 10 is the front side, the lens 18 may be provided at a position facing all the openings 151, but the lens 18 may be provided at a position facing some of the openings 151 depending on the light transmittance required for the organic EL display device 10. In addition, when a device (e.g., a smartphone, etc.) including the organic EL display device 10 includes a proximity sensor including a light-emitting element that emits infrared light through one opening 151 and a light-receiving element that receives the infrared light through another opening 151, the lens 18 may be provided at a position facing the opening 151 through which the infrared light passes.

In a first embodiment of the organic EL display device 10 (see FIG. 1), when viewed from the side with the first substrate 11 positioned downward and the second interlayer insulating film 16 positioned upward, the lens 18 may be provided above the opening 151, for example, at a position facing the opening 151 on the second interlayer insulating film 16.

In a second embodiment of the organic EL display device 10 (see FIG. 2), in a side view with the first substrate 11 positioned downward and the second interlayer insulating film 16 positioned upward, the lens 18 may be provided below the opening 151, for example, in a position facing the opening 151 below the insulating film 17 surrounding the first electrode 13.

As a third aspect (see FIG. 3) and a fourth aspect (see FIG. 4) of the organic EL display device 10, in a side view in which the first substrate 11 is positioned downward and the second interlayer insulating film 16 is positioned upward, the lens 18 may include a first lens 181 provided above the opening 151, for example, at a position facing the opening 151 on the second interlayer insulating film 16, and a second lens 182 provided below the opening 151, for example, at a position facing the opening 151 below the insulating film 17 surrounding the first electrode 13. In this case, when the first lens 181 is provided above the opening 151, the second lens 182 may not be provided below the opening 151, and when the second lens 182 is provided below the opening 151, the first lens 181 may not be provided above the opening 151 (see FIG. 3). Also, a first lens 181 may be provided above the opening 151, and a second lens 182 may be provided below the opening 151 (see FIG. 4).

As a fifth aspect of the organic EL display device 10 (see FIG. 5), in a side view with the first substrate 11 positioned downward and the second interlayer insulating film 16 positioned upward, the lens 18 may be provided above the opening 151, for example, at a position facing the opening 151 on the second interlayer insulating film 16, and also at a position facing the organic compound layer 14. In a top-emission type organic EL display device 10 in which light generated in the organic compound layer 14 is extracted from the second interlayer insulating film 16 side, the light generated in the organic compound layer 14 is extracted through the lens 18, which further increases the brightness of the organic EL display device 10.

The shape of the lens 18 is not particularly limited, and may be, for example, a spherical lens or a cylindrical lens. When the lens 18 is a spherical lens, the lens 18 may be provided for each opening 151 (see FIG. 6). When the lens 18 is a cylindrical lens, the lens 18 may be provided for multiple openings 151 (see FIG. 7).

The material constituting the lens 18 may be any material having optical transparency, and may be, for example, a resin material (organic material) such as a photosensitive resist material, or an inorganic material such as SiO _2. The material constituting the lens 18 can be selected with a relatively high degree of freedom by optical design.

In a plan view from the second electrode 15 side toward the first electrode 13 side, the size of the lens 18 may be such that light (e.g., external light) incident on the lens 18 passes through the opening 151, that is, the size that can cover the opening 151, but the size may be such that a part of the lens 18 does not overlap the light-emitting region 14A of the organic compound layer 14, and may be such that the lens 18 does not overlap the first electrode 13. In the organic EL display device 10 according to this embodiment, it is presumed that light is emitted from the light-emitting region 14A of a part of the organic compound layer 14. In this embodiment, since the outer peripheral edge of the first electrode 13 is covered with the insulating layer 17, the region on the first electrode 13 surrounded by the insulating layer 17 is in direct contact with the organic compound layer 14. Since holes are injected from the region on the first electrode 13 to the organic compound layer 14 in the thickness direction of the organic EL display device 10, the region of the organic compound layer 14 corresponding to the region is considered to be the light-emitting region 14A (see FIG. 9). Therefore, if a part of the lens 18 overlaps the light-emitting region 14A of the organic compound layer 14, a part of the light generated in the organic compound layer 14 and extracted to the second interlayer insulating film 16 side or the substrate 11 side passes through the lens 18. This changes the direction in which the light is extracted in the organic EL display device 10, which may make it difficult to display images, etc., with high resolution. Therefore, the size of the lens 18 is such that it does not overlap the light-emitting region 14A of the organic compound layer 14, preferably such that it does not overlap the first electrode 13, and the lens 18 is provided at a position that does not overlap the light-emitting region 14A of the organic compound layer 14, preferably such that it does not overlap the first electrode 13, so that the light can be extracted in the desired direction and images, etc. can be displayed with high resolution.

When the organic EL display device 10 according to this embodiment is a top emission type in which light generated in the organic compound layer 14 is extracted from the second interlayer insulating film 16 side, the size of the second lens 182 provided at a position opposite the opening 151 in a plan view from the first electrode 13 side toward the second electrode side may be such that a part of the second lens 182 overlaps the light emitting region 14A of the organic compound layer 14 or the first electrode 13. In this case, the light generated in the organic compound layer 14 is extracted from the opposite side to the second lens 182 and does not pass through the second lens 182, so there is no risk of a problem occurring in which the direction in which light is extracted in the organic EL display device 10 changes.

In the organic EL display device 10 having the above-mentioned configuration, light (e.g., external light) traveling in the thickness direction of the organic EL display device 10 (e.g., in the organic EL display device 10 shown in FIG. 1, in the direction from the substrate 11 toward the second interlayer insulating film 16 or in the opposite direction) is condensed toward the opening 151 through the lens 18 (first lens 181 and/or second lens 182) provided at a position opposite the opening 151, so that the light transmittance in the thickness direction of the organic EL display device 10 can be improved. Therefore, according to the present disclosure, it is possible to provide an organic EL display device 10 with excellent transmission performance.

An example of a method for manufacturing an organic EL display device 10 having the above-mentioned configuration will be described. FIGS. 10A to 10D are cross-sectional views for explaining each step of the method for manufacturing an organic EL display device 10 according to this embodiment. In the following, an example of a method for manufacturing an organic EL display device 10 having the configuration shown in FIG. 1 will be described.

A substrate 11 having a first surface 11A and a second surface 11B facing the first surface 11A, a TFT element (not shown) and a first interlayer insulating film 12 on the first surface 11A is prepared, and a first electrode 13 is formed at a predetermined position on the first interlayer insulating film 12 (see FIG. 10A). For example, a deposition mask having a through hole corresponding to the first electrode 13 is prepared, and a material constituting the first electrode 13 (e.g., a transparent conductive material such as ITO or InZnO) is vacuum-deposited at a predetermined position on the first interlayer insulating film 12 through the deposition mask to form the first electrode 13. Alternatively, a material constituting the first electrode 13 (e.g., a transparent conductive material such as ITO or InZnO) may be formed on the first interlayer insulating film 12, and the first electrode 13 may be formed at a predetermined position on the first interlayer insulating film 12 by a photolithography method. In addition, at a predetermined position on the first interlayer insulating film 12 (the position where the first electrode 13 is formed), a through-hole via may be formed in the first interlayer insulating film 12, and by forming the first electrode 13 at the predetermined position, the first electrode 13 and the TFT element can be electrically connected via the through-hole via.

Next, an insulating film (e.g., polyimide, etc.) that covers the first electrode 13 and the first interlayer insulating film 12 is formed by a conventionally known coating method (e.g., die coating, spin coating, etc.), and the insulating film is patterned to form an insulating film 17 that surrounds the first electrode 13 (see FIG. 10B).

Next, the organic compound layer 14 is formed on the exposed first electrode 13 (see FIG. 10C). For example, a deposition mask having through holes corresponding to the organic compound layer 14 may be prepared, and the material constituting the organic compound layer 14 (e.g., quinolinol complexes, oxazole complexes, various laser dyes, fluorescent organic compounds such as polyparaphenylenevinylene, etc.) may be vacuum-deposited onto the first electrode 13 through the deposition mask to form the organic compound layer 14. Note that an insulating film (e.g., lithium fluoride (LiF), etc.) having a thickness of about 0.2 nm to 3.0 nm may be formed on the organic compound layer 14 as desired.

A second electrode 15 is formed on the organic compound layer 14, and a second interlayer insulating film 16 is formed on the second electrode 15 (see FIG. 10D). For example, the second electrode 15 may be formed by vacuum-depositing a material constituting the second electrode 15 (e.g., magnesium (Mg), silver (Ag), magnesium-silver alloy (Mg/Ag), etc.) to form a metal layer that covers the organic compound layer 14 and the insulating film 17, and patterning the metal layer to form an opening 151.

Next, the lens 18 is formed at a position facing the opening 151 of the second electrode 15 .
As a method for forming the lens 18, for example, a negative photosensitive resist film 20 may be formed on the second interlayer insulating film 16 (see FIG. 11A), exposed from the substrate 11 side using the second electrode 15 as a mask (see FIG. 11B), and developed to form the lens 18 at a position facing the opening 151 (see FIG. 11C). The exposure light L is irradiated onto the negative photosensitive resist film 20 through the opening 151 of the second electrode 15, but diffraction of the exposure light may occur near the edge of the opening 151. As a result, an exposure amount distribution is formed in the negative photosensitive resist film 20 irradiated with the exposure light L through the opening 151, so that the lens 18 can be formed at a position facing the opening 151.

As another method for forming the lens 18, for example, a negative photosensitive resist film 20 may be formed on the second interlayer insulating film 16 (see FIG. 11A), exposed through a multi-tone exposure mask 30 having at least a light-shielding portion 31, a semi-transparent portion 32, and a transparent portion 33 (see FIG. 12A), and developed to form the lens 18 at a position opposite the opening 151 (see FIG. 12B).

As another method for forming the lens 18, for example, a droplet 40 of a material constituting the lens 18 (e.g., a resin material such as a photosensitive (ultraviolet-curable) resist material) may be dropped by an inkjet method at a position facing the opening 151 on the second interlayer insulating film 16 (see FIG. 13A), and the droplet 40 of the material may be irradiated with ultraviolet light UV or the like to harden the lens 18 (see FIG. 13B). Alternatively, a material 50 constituting the lens 18 (e.g., a resin material such as a photosensitive (ultraviolet-curable) resist material) may be applied to a position facing the opening 151 on the second interlayer insulating film 16, and molded using a plate 60 (a transparent plate made of quartz glass or the like) having a recess 61 corresponding to the lens 18, and the material 50 may be hardened by exposure through the plate 60 (see FIG. 14A), and then released to form the lens 18 (see FIG. 14B).

By forming the lens 18 at a position corresponding to the opening 151 of the second electrode 15 in the manner described above, the organic EL display device 10 according to this embodiment can be manufactured. The organic EL display device 10 manufactured in this manner can improve the light transmittance in the thickness direction of the organic EL display device 10.

The above-described embodiments are described to facilitate understanding of the present disclosure, and are not described to limit the present disclosure. Therefore, each element disclosed in the above embodiments is intended to include all design modifications and equivalents that fall within the technical scope of the present disclosure.

Claims (5)

a substrate having a first surface and a second surface opposite to the first surface;
a plurality of first electrodes arranged in a matrix on the first surface of the substrate;
a plurality of organic compound layers respectively positioned on the plurality of first electrodes;
a second electrode located on the organic compound layers and having a plurality of openings located between the organic compound layers adjacent to each other in a plan view from the first surface side to the second surface side;
a lens provided at a position facing at least a part of the openings,
An organic electroluminescent display device, wherein, in a planar view from the second electrode side toward the first electrode side or from the first electrode side toward the second electrode side, the lens is provided in a position that does not overlap the first electrode and is located opposite the opening on the opposite side of the substrate with respect to the second electrode . a substrate having a first surface and a second surface opposite to the first surface;
a plurality of first electrodes arranged in a matrix on the first surface of the substrate;
a plurality of organic compound layers respectively positioned on the plurality of first electrodes;
a second electrode located on the organic compound layers and having a plurality of openings located between the organic compound layers adjacent to each other in a plan view from the first surface side to the second surface side;
a lens provided at a position facing at least a part of the opening;
Equipped with
the lens is provided at a position not overlapping the first electrode in a plan view from the second electrode side toward the first electrode side or from the first electrode side toward the second electrode side,
The lens includes a first lens provided at a position facing the opening on the side opposite the substrate with respect to the second electrode, and a second lens provided at a position facing the opening on the substrate side with respect to the second electrode. The organic electroluminescence display device according to claim 1 , wherein the organic compound layer includes an organic light-emitting layer. 4. The organic electroluminescence display device according to claim 1, wherein the lens includes a cylindrical lens. 5. The organic electroluminescence display device according to claim 1 , wherein the lens includes a spherical lens.

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