WO2023100672A1 - Display device and electronic apparatus - Google Patents

Abstract

Provided is a display device capable of achieving an increase in brightness.　The display device comprises a plurality of two-dimensionally arranged light emitting elements, and a lower layer provided under the plurality of light emitting elements. The lower layer includes one or a plurality of recesses per light emitting element, and the light emitting elements are provided in alignment with the recesses. When the lower layer has one recess per light emitting element, the shape of a cross section taken across one recess in a plane passing the geometric center of the light emitting element in plan view and parallel to the thickness direction of the display device includes a plurality of recessed portions.

Description

Displays and electronics

The present disclosure relates to a display device and an electronic device including the same.

In recent years, OLED (Organic Light Emitting Diode) display devices have become widespread. An OLED display device comprises a plurality of light-emitting elements arranged two-dimensionally on a circuit board, and each light-emitting element sequentially comprises a first electrode, an organic layer including a light-emitting layer, and a second electrode.

Patent Document 1 describes a technique for improving luminance by forming a first electrode layer, an organic layer, and a second electrode layer following concave portions on the surface of a substrate.

JP 2019-133816 A

However, the technique described in Patent Document 1 may not improve the luminance sufficiently, so there is room for improvement in the technique described in Patent Document 1. With the technique described in Patent Document 1, especially when the concave portion is shallow, improvement in brightness tends to be insufficient.

An object of the present disclosure is to provide a display device capable of improving luminance and an electronic device including the same.

In order to solve the above problems, the display device according to the present disclosure includes:
a plurality of light emitting elements arranged two-dimensionally;
a lower layer provided under the plurality of light emitting elements; and
the lower layer has one or more recesses for each light emitting element,
The light emitting element is provided following the recess,
When the lower layer has one recess for each light emitting element, a cross section obtained by cutting one recess in a plane that passes through the geometric center of the light emitting element in plan view and is parallel to the thickness direction of the display device. The display device, the shape of which includes a plurality of concave portions.

In the present disclosure, the lower layer may be an insulating layer or a substrate.

In the present disclosure, the recess may have an annular shape in plan view. The ring may be generally toric, generally elliptical, or generally polygonal. A cross-sectional shape obtained by cutting a recess having an annular shape in plan view along a plane parallel to the width direction of the recess and parallel to the thickness direction of the display device has an arch shape or a substantially polygonal shape. good too. The arch shape may be substantially circular, substantially elliptical, or substantially parabolic. The substantially polygonal shape may be a substantially square shape such as a substantially trapezoidal shape.

In the present disclosure, the lower layer may have a plurality of recesses for each light emitting element. In this case, the plurality of recesses may have a concentric shape in plan view, or may have a dot shape in plan view. The plurality of recesses having dot shapes in plan view may be arranged in a prescribed pattern. The arrangement may be a one-dimensional arrangement or a two-dimensional arrangement. The plurality of recesses may include a first recess having an annular shape in plan view and a second recess having a dot shape in plan view provided inside the first recess. The dot shape may be substantially circular, substantially elliptical, substantially polygonal, or substantially cross-shaped. The substantially polygonal shape may be a substantially square shape or a substantially hexagonal shape.

A concave portion having a dot shape in plan view may have a bowl shape. A cross-sectional shape obtained by cutting a recess having a dot shape in plan view along a plane parallel to the width direction of the recess and parallel to the thickness direction of the display device has an arch shape or a substantially polygonal shape. may The arch shape may be substantially circular, substantially elliptical, or substantially parabolic. The substantially polygonal shape may be a substantially square shape such as a substantially trapezoidal shape.

In the present disclosure, when the lower layer has a plurality of recesses for each light emitting element, the widths of the recesses may differ, the depths of the recesses may differ, and the widths and widths of the recesses may differ. Both depths may be different.

In the present disclosure, the recess may have the same width over the entire display area of the display device, or may have two or more widths over the entire display area of the display device. When the recess has two or more widths over the entire display area of the display device, the width of the recess may vary depending on the position of the display area.

In the present disclosure, the recesses may have the same depth over the entire display area of the display device, or may have two or more depths over the entire display area of the display device. When the concave portion has two or more depths over the entire display area of the display device, the depth of the concave portion may differ depending on the position of the display area.

In the present disclosure, the display device may further include a protective layer covering the plurality of light emitting elements and a planarization layer provided on the protective layer, and the planarization layer may function as a color filter.

In the present disclosure, the display device may include a protective layer covering the plurality of light emitting elements, a planarizing layer provided on the protective layer, and a color filter provided on the planarizing layer.

In the present disclosure, the display device may further include a plurality of lenses provided above the plurality of light emitting elements, and one or more lenses may be provided for each light emitting element. In this case, the concave portion and the lens may have the same shape in plan view. For example, the concave portion and the lens may have an annular shape in plan view, or may have a dot shape in plan view. The lens may be a convex lens. A cross-sectional shape obtained by cutting a convex lens along a plane parallel to the width direction of the lens and parallel to the thickness direction of the display device may have an arch shape or a substantially polygonal shape. . The arch shape may be substantially circular, substantially elliptical, or substantially parabolic. The substantially polygonal shape may be a substantially square shape such as a substantially trapezoidal shape.

In the present disclosure, the display device may have multiple recesses and multiple lenses for each light emitting element. In this case, the plurality of recesses and the plurality of lenses may have the same shape in plan view.

In the present disclosure, each light-emitting element may include, in order, a first electrode, an organic layer including a light-emitting layer, and a second electrode.

The display device according to the present disclosure may be provided in electronic equipment.

FIG. 1 is a plan view showing an example of the configuration of a display device according to one embodiment. FIG. 2 is a plan view showing an enlarged part of the display area of the display device according to the embodiment. FIG. 3 is a cross-sectional view taken along line III--III in FIG. FIG. 4A is a plan view showing an example of the configuration of a circuit board provided with first electrodes and an insulating layer. FIG. 4B is a cross-sectional view taken along line IVB--IVB of FIG. 4A. FIG. 5A is a plan view showing an example of the configuration of a circuit board provided with first electrodes and an insulating layer. FIG. 5B is a cross-sectional view along line VB-VB in FIG. 5A. FIG. 6A is a plan view showing an example of the configuration of a circuit board provided with first electrodes and an insulating layer. FIG. 6B is a cross-sectional view along line VIB--VIB of FIG. 6A. FIG. 7A is a plan view showing an example of the configuration of a circuit board provided with first electrodes and an insulating layer. FIG. 7B is a cross-sectional view taken along line VIIB--VIIB of FIG. 7A. FIG. 8A is a cross-sectional view showing an example of the configuration of a circuit board provided with a first electrode and an insulating layer. FIG. 8B is a cross-sectional view showing an example of the configuration of a circuit board provided with a first electrode and an insulating layer. FIG. 9A is a cross-sectional view showing an example of the configuration of a circuit board provided with first electrodes and an insulating layer. FIG. 9B is a cross-sectional view showing an example of the configuration of a circuit board provided with first electrodes and an insulating layer. FIG. 10 is a cross-sectional view showing an example of the configuration of a circuit board provided with first electrodes and an insulating layer. FIG. 11 is a cross-sectional view showing an example of the configuration of the display device. FIG. 12A is a diagram showing cross-sectional shapes of first electrodes of Comparative Examples 1A, 1B, 1C, 2A, 2B, and 2C. FIG. 12B is a diagram showing the cross-sectional shape of the first electrode of Reference Examples 1A, 1B, 1C, 2A, 2B, and 2C. FIG. 12C is a diagram showing the cross-sectional shape of the first electrode of Reference Examples 3A, 3B, 3C, 4A, 4B, and 4C. FIG. 13A is a front view showing an example of the appearance of a digital still camera. FIG. 13B is a rear view showing an example of the appearance of the digital still camera. FIG. 14 is a perspective view of an example of the appearance of a head mounted display. FIG. 15 is a perspective view showing an example of the appearance of the television device.

Embodiments of the present disclosure will be described in the following order with reference to the drawings. In addition, in all the drawings of the following embodiments, the same reference numerals are given to the same or corresponding parts.
1 One embodiment (example of display device)
2 Modification (Modification of display device)
3 Reference example (Reference example of display device)
4 Application example (example of electronic equipment)

<1 one embodiment>
[Configuration of display device 10]
FIG. 1 is a plan view showing an example of the configuration of a display device 10 according to one embodiment. The display device 10 has a display region R1 and a peripheral region R2 provided around the display region R1. The display area R1 has a rectangular shape in plan view. In this specification, a planar view means a planar view when an object is seen from a direction D _Z (hereinafter referred to as “front direction D _Z ”) perpendicular to the display surface of the display device 10 . In this specification, the direction parallel to the long sides of the display region R1 is called the horizontal direction _DX , and the direction parallel to the short sides of the display region R1 is called the vertical direction _DY .

FIG. 2 is a plan view showing an enlarged part of the display region R1 of the display device 10 according to one embodiment. A plurality of sub-pixels 100R, 100G, and 100B are two-dimensionally arranged in a prescribed arrangement pattern within the display region R1. The prescribed arrangement pattern is, for example, a delta arrangement, a stripe arrangement or a mosaic arrangement. Note that FIG. 2 shows an example of a delta arrangement. The peripheral region R2 is provided with a pad portion 101, an image display driver (not shown), and the like. A flexible printed circuit (FPC) (not shown) may be connected to the pad section 101 .

The sub-pixel 100R can emit red light. The sub-pixel 100G can emit green light. The sub-pixel 100B can emit blue light. Red is an example of the first of the three primary colors. Green is an example of the second of the three primary colors. Blue is an example of the third primary color of the three primary colors. In FIG. 2, blocks marked with symbols "R", "G", and "B" represent the sub-pixel 100R, the sub-pixel 100G, and the sub-pixel 100B, respectively.

In the following description, when sub-pixels 100R, 100G, and 100B are collectively referred to as sub-pixel 100 without particular distinction. One pixel (one pixel) is composed of three adjacent sub-pixels 100R, 100G, and 100B.

The sub-pixels 100R, 100G, and 100B have, for example, a circular shape, an elliptical shape, or a rectangular shape in plan view. In this specification, the rectangular shape includes a square shape. Note that FIG. 2 shows an example in which the sub-pixels 100R, 100G, and 100B have a circular shape in plan view.

The display device 10 is an example of a light emitting device. The display device 10 is a top emission type OLED display device. The display device 10 may be a microdisplay. The display device 10 may be provided in a VR (Virtual Reality) device, an MR (Mixed Reality) device, an AR (Augmented Reality) device, an Electronic View Finder (EVF), a small projector, or the like.

FIG. 3 is a cross-sectional view taken along line III-III in FIG. The display device 10 includes a circuit board 11, a plurality of light emitting elements 20, an insulating layer 12, a protective layer 13, a planarizing layer 14, a color filter 15, a planarizing layer 16, and a lens array 17. . A plurality of sub-pixels 100R, 100G, and 100B are configured by combining the color filters 15 and the light-emitting elements 20 .

In the following description, in each layer constituting the display device 10, the surface on the top side (display surface side) of the display device 10 is referred to as a first surface, and the bottom side (opposite side to the display surface) of the display device 10 is referred to as a first surface. is called the second surface.

(circuit board 11)
FIG. 4A is a plan view of the circuit board 11 provided with the first electrodes 21 and the insulating layer 12. FIG. FIG. 4B is a cross-sectional view taken along line IVB--IVB of FIG. 4A. The circuit board 11 is a so-called backplane and drives the plurality of light emitting elements 20 . The circuit board 11 includes a substrate 11a and an insulating layer 11b in this order. A plurality of wirings 11d, a driving circuit (not shown) for driving the plurality of light emitting elements 20, a power supply circuit (not shown) for supplying power to the plurality of light emitting elements 20, and the like are provided on the first surface of the substrate 11a. is provided.

(Substrate 11a)
The substrate 11a may be made of, for example, a semiconductor that facilitates the formation of transistors or the like, or may be made of glass or resin with low permeability to moisture and oxygen. Specifically, the substrate 11a may be a semiconductor substrate, a glass substrate, a resin substrate, or the like. Semiconductor substrates include, for example, amorphous silicon, polycrystalline silicon, monocrystalline silicon, or the like. The glass substrate includes, for example, high strain point glass, soda glass, borosilicate glass, forsterite, lead glass, quartz glass, or the like. The resin substrate contains, for example, at least one selected from the group consisting of polymethyl methacrylate, polyvinyl alcohol, polyvinyl phenol, polyethersulfone, polyimide, polycarbonate, polyethylene terephthalate and polyethylene naphthalate.

(insulating layer 11b)
The insulating layer 11 b is an example of a lower layer provided under the plurality of light emitting elements 20 . The insulating layer 11b is provided on the first surface of the substrate 11a to cover and planarize the plurality of wirings 11d, the drive circuit, the power supply circuit, and the like. The insulating layer 11b insulates between the wiring 11d provided on the first surface of the substrate 11a, the driving circuit and the like and the light emitting element 20. As shown in FIG.

The insulating layer 11b has a plurality of vias 11c inside. The insulating layer 11b may include a plurality of wirings 11d therein. Each via 11c is a connection member that electrically connects the light emitting element 20 and the wiring 11d. The via 11c contains, for example, at least one metal selected from the group consisting of copper (Cu) and titanium (Ti). The wiring 11d includes, for example, a first barrier layer, a metal layer, and a second barrier layer in this order. The first barrier layer and the second barrier layer contain, for example, titanium nitride (TiN). The metal layer contains, for example, aluminum (Al) or an aluminum alloy.

The insulating layer 11b has a plurality of recesses 110 on its first surface. The concave portion 110 is for forming the light emitting element 20 into a shape that follows the concave portion 110 . One recess 110 is provided for each light emitting element 20 . A cross section obtained by cutting one concave portion 110 along a plane passing through the geometric center of the light emitting element 20 in plan view and parallel to the thickness direction of the display device 10 includes two concave portions. The concave portion has, for example, a downwardly convex curved shape, a substantially trapezoidal shape, or a substantially rectangular shape. The downwardly convex curved shape is, for example, a substantially circular arc shape, a substantially elliptical arc shape, or a substantially parabolic shape.

The concave portion 110 has an annular shape in plan view. The annular ring is centered, for example, on the geometric center of the light emitting element 20 in plan view. The recessed portion 110 may have a bottom portion 111, an inner peripheral wall portion 112a, and an outer peripheral wall portion 112b. The bottom portion 111 may be planar and parallel to the first surface of the substrate 11a. The inner peripheral wall portion 112a and the outer peripheral wall portion 112b may be inclined surfaces inclined with respect to the first surface of the substrate 11a, or may be vertical surfaces perpendicular to the first surface of the substrate 11a. good. The cross-sectional shape obtained by cutting the inner peripheral wall portion 112a and the outer peripheral wall portion 112b along a plane parallel to the width direction of the recess 110 and parallel to the thickness direction of the display device 10 may be linear. and may be smooth curved. The curved line is, for example, a concave curved line or a convex curved line.

The insulating layer 11b may be an organic insulating layer, an inorganic insulating layer, or a laminate thereof. The organic insulating layer contains, for example, at least one selected from the group consisting of polyimide-based resins, acrylic-based resins, novolak-based resins, and the like. The inorganic insulating layer contains, for example, at least one selected from the group consisting of silicon oxide (SiO _x ), silicon nitride (SiN _x ), silicon oxynitride (SiO _x N _y ), and the like.

(Light emitting element 20)
The light emitting element 20 is a white OLED element, and can emit white light under control of a drive circuit or the like. The white OLED element may be a white Micro-OLED (MOLED) element.

At least part of the light emitting element 20 is preferably provided along the recess 110 . That is, it is preferable that the peripheral edge of the light emitting element 20 is positioned outside the outer periphery of the annular recess 110 in plan view. The plurality of light emitting elements 20 are two-dimensionally arranged on the first surface of the circuit board 11 in a prescribed arrangement pattern. The multiple light emitting elements 20 include multiple first electrodes 21 , an OLED layer 22 , and a second electrode 23 in this order on the first surface of the circuit board 11 .

(First electrode 21)
The first electrode 21 is the anode. When a voltage is applied between the first electrode 21 and the second electrode 23 , holes are injected from the first electrode 21 into the OLED layer 22 . The first electrodes 21 are separately provided for the plurality of light emitting elements 20 . The plurality of first electrodes 21 are two-dimensionally arranged on the first surface of the circuit board 11 in the same arrangement pattern as the plurality of light emitting elements 20 . At least part of the first electrode 21 follows the recess 110 . That is, at least part of the first electrode 21 has the recess 210 . The first electrode 21 having the concave portion 210 can increase the area compared to the flat-shaped first electrode. Therefore, even when the aperture ratio is reduced due to the high definition of the pixel, the reduction in the effective area of the first electrode 21 can be suppressed. Therefore, even when the aperture ratio is reduced due to the increase in pixel definition, it is possible to suppress the decrease in luminance. The peripheral edge of the first electrode 21 is preferably positioned outside the outer periphery of the annular recess 110 in plan view. Preferably, the first electrodes 21 have approximately the same thickness. The depth of the concave portion 210 is, for example, 30 nm or more and 500 nm or less, preferably 30 nm or more and 300 nm or less.

The first electrode 21 may be composed of, for example, a metal layer, or may be composed of a metal layer and a transparent conductive oxide layer. When the first electrode 21 is composed of a metal layer and a transparent conductive oxide layer, from the viewpoint of placing a layer having a high work function adjacent to the OLED layer 22, the transparent conductive oxide layer is the OLED layer. It is preferably provided on the 22 side.

The metal layer also functions as a reflective layer that reflects light emitted by the OLED layer 22 . The metal layer is, for example, chromium (Cr), gold (Au), platinum (Pt), nickel (Ni), copper (Cu), molybdenum (Mo), titanium (Ti), tantalum (Ta), aluminum (Al). , magnesium (Mg), iron (Fe), tungsten (W) and silver (Ag). The metal layer may contain the at least one metal element as a constituent element of an alloy. Specific examples of alloys include aluminum alloys and silver alloys. Specific examples of aluminum alloys include AlNd and AlCu.

A base layer (not shown) may be provided adjacent to the second surface side of the metal layer. The underlayer is for improving the crystal orientation of the metal layer when the metal layer is formed. The underlayer contains, for example, at least one metal element selected from the group consisting of titanium (Ti) and tantalum (Ta). The underlayer may contain the at least one metal element as a constituent element of the alloy.

The transparent conductive oxide layer contains a transparent conductive oxide. Transparent conductive oxides include, for example, transparent conductive oxides containing indium (hereinafter referred to as "indium-based transparent conductive oxides") and transparent conductive oxides containing tin (hereinafter referred to as "tin-based transparent conductive oxides"). ”) and transparent conductive oxides containing zinc (hereinafter referred to as “zinc-based transparent conductive oxides”).

Indium-based transparent conductive oxides include, for example, indium tin oxide (ITO), indium zinc oxide (IZO), indium gallium oxide (IGO) or indium gallium zinc oxide (IGZO) and fluorine-doped indium oxide (IFO). Among these transparent conductive oxides, indium tin oxide (ITO) is particularly preferred. This is because indium tin oxide (ITO) has a particularly low hole injection barrier to the OLED layer 22 in terms of work function, so that the driving voltage of the display device 10 can be particularly lowered. Tin-based transparent conductive oxides include, for example, tin oxide, antimony-doped tin oxide (ATO), or fluorine-doped tin oxide (FTO). Zinc-based transparent conductive oxides include, for example, zinc oxide, aluminum-doped zinc oxide (AZO), boron-doped zinc oxide, or gallium-doped zinc oxide (GZO).

(OLED layer 22)
The OLED layer 22 is an example of an organic layer including a light-emitting layer. The OLED layer 22 can emit white light by recombination of holes injected from the first electrode 21 and electrons injected from the second electrode 23 .

The OLED layer 22 is provided between the multiple first electrodes 21 and the second electrodes 23 . The OLED layer 22 follows the first surface (uneven surface) of the circuit board 11 on which the first electrode 21 is provided. OLED layers 22 preferably have approximately the same thickness. The OLED layer 22 is provided continuously over the plurality of light emitting elements 20 within the display region R1, and is shared by the plurality of light emitting elements 20 within the display region R1.

The OLED layer 22 may be an OLED layer with a single-layer light emitting unit, an OLED layer with two layers of light emitting units (tandem structure), or an OLED layer with a structure other than these. may An OLED layer comprising a single layer of light-emitting units includes, for example, a hole-injecting layer, a hole-transporting layer, a red-emitting layer, a light-emitting separating layer, a blue-emitting layer, from the first electrode 21 toward the second electrode 23 . It has a configuration in which a green light-emitting layer, an electron transport layer, and an electron injection layer are laminated in this order. An OLED layer comprising two layers of light-emitting units is, for example, a hole-injection layer, a hole-transport layer, a blue-light-emitting layer, an electron-transport layer, a charge-generating layer, from the first electrode 21 toward the second electrode 23 . It has a structure in which a hole transport layer, a yellow light emitting layer, an electron transport layer, and an electron injection layer are laminated in this order.

The hole injection layer is intended to increase the efficiency of hole injection into each light-emitting layer and to suppress leakage. The hole-transporting layer is for increasing the efficiency of hole-transporting to each light-emitting layer. The electron injection layer is for increasing the efficiency of electron injection into each light-emitting layer. The electron transport layer is for enhancing electron transport efficiency to each light-emitting layer. The emission separation layer is a layer for adjusting the injection of carriers into each emission layer, and the emission balance of each color is adjusted by injecting electrons and holes into each emission layer through the emission separation layer. The charge-generating layer is for supplying electrons and holes to the two light-emitting layers sandwiching the charge-generating layer.

By applying an electric field to each of the red light emitting layer, the green light emitting layer, the blue light emitting layer, and the yellow light emitting layer, holes injected from the first electrode 21 or the charge generation layer and holes injected from the second electrode 23 or the charge generation layer Recombination with injected electrons occurs, and red light, green light, blue light, and yellow light can be emitted.

(Second electrode 23)
The second electrode 23 is the cathode. When a voltage is applied between the first electrode 21 and the second electrode 23 , electrons are injected from the second electrode 23 into the OLED layer 22 . The second electrode 23 is a transparent electrode having transparency to visible light. In this specification, visible light refers to light in the wavelength range of 360 nm to 830 nm. A second electrode 23 is provided on the first surface of the OLED layer 22 . The second electrode 23 follows the first surface (uneven surface) of the circuit board 11 on which the first electrode 21 and the OLED layer 22 are provided. The second electrodes 23 preferably have approximately the same thickness. The second electrode 23 is provided continuously over the plurality of light emitting elements 20 within the display region R1 and is shared by the plurality of light emitting elements 20 within the display region R1.

It is preferable for the second electrode 23 to be made of a material with a high transmittance and a small work function, in order to increase the luminous efficiency. The second electrode 23 is composed of, for example, at least one layer of a metal layer and a transparent conductive oxide layer. More specifically, the second electrode 23 is composed of a single layer film of a metal layer or a transparent conductive oxide layer, or a laminated film of a metal layer and a transparent conductive oxide layer. When the second electrode 23 is composed of a laminated film, the metal layer may be provided on the OLED layer 22 side, and the transparent conductive oxide layer may be provided on the OLED layer 22 side. From the viewpoint of placing a layer having a work function adjacent to the OLED layer 22, it is preferable that the metal layer is provided on the OLED layer 22 side.

The metal layer contains, for example, at least one metal element selected from the group consisting of magnesium (Mg), aluminum (Al), silver (Ag), calcium (Ca) and sodium (Na). The metal layer may contain the at least one metal element as a constituent element of an alloy. Specific examples of alloys include MgAg alloys, MgAl alloys, AlLi alloys, and the like. The transparent conductive oxide layer includes a transparent conductive oxide. As the transparent conductive oxide, the same material as the transparent conductive oxide of the first electrode 21 can be exemplified.

(Protective layer 13)
The protective layer 13 has transparency to visible light. The protective layer 13 is provided on the first surface of the second electrode 23 and covers the plurality of light emitting elements 20 . The protective layer 13 shields the light emitting element 20 from the outside air, and can suppress moisture intrusion into the light emitting element 20 from the external environment. Moreover, when the second electrode 23 is composed of a metal layer, the protective layer 13 may have a function of suppressing oxidation of this metal layer. The protective layer 13 may have unevenness on the first surface. The unevenness may follow the unevenness of the first surface of the circuit board 11 on which the plurality of light emitting elements 20 are two-dimensionally arranged.

The protective layer 13 includes a first protective layer 13 a and a second protective layer 13 b in order on the first surface of the second electrode 23 . The first protective layer 13a contains, for example, a low hygroscopic inorganic material or polymer resin. The first protective layer 13a may have a single layer structure or a multilayer structure. When increasing the thickness of the first protective layer 13a, it is preferable to have a multilayer structure. This is for alleviating the internal stress in the protective layer 13 . The inorganic material is, for example, selected from the group consisting of silicon oxide (SiO _x ), silicon nitride (SiN _x ), silicon oxynitride (SiO _x N _y ), titanium oxide (TiO _x ) and aluminum oxide (AlO _x ). contains at least one Polymer resins include, for example, at least one selected from the group consisting of thermosetting resins, ultraviolet-curable resins, and the like. Specifically, the polymer resin includes at least one selected from the group consisting of acrylic resins, polyimide resins, novolac resins, epoxy resins, norbornene resins, and the like.

The second protective layer 13b is, for example, a metal oxide layer. The metal oxide layer preferably consists of a deposited monolayer. When the metal oxide layer is composed of a deposited monomolecular layer, it is possible to improve the effect of the protective layer 13 on suppressing moisture intrusion. The second protective layer 13b preferably contains a material different from that of the first protective layer 13a. It is possible to suppress formation of pinholes generated in the first protective layer 13a that are also connected to the second protective layer 13b. Metal oxide layers include, for example, aluminum oxide or titanium oxide.

(Planarization layer 14)
The planarizing layer 14 is provided on the first surface of the protective layer 13 and planarizes the unevenness of the first surface of the protective layer 13 . The planarization layer 14 contains, for example, an inorganic material or a polymeric resin. Examples of the inorganic material include materials similar to those of the first protective layer 13a. As the polymer resin, the same material as the polymer resin of the first protective layer 13a can be exemplified.

When the refractive index of the planarizing layer 14 is n ₁ and the refractive index of the protective layer 13 is n ₂ , it is preferable to satisfy the relationship n ₁ >n ₂ . When the relationship n ₁ >n ₂ is satisfied, an internal lens is formed by the planarizing layer 14 and the protective layer 13, and the light emitted from the light emitting element 20 can be focused in the front direction _DZ . The front light extraction efficiency can be improved. The refractive index difference Δn (=n ₁ −n ₂ ) between the refractive index n ₁ of the planarizing layer 14 and the refractive index n ₂ of the protective layer 13 is 0.1 or more from the viewpoint of improving the function of the internal lens. It is preferably 0.6 or less. Here, the refractive index represents the refractive index for light with a wavelength of 550 nm.

(Color filter 15)
A color filter 15 is provided above the plurality of light emitting elements 20 . More specifically, the color filters 15 are provided on the first surface of the planarization layer 14 . The color filter 15 is, for example, an on-chip color filter (OCCF). The color filter 15 includes, for example, a plurality of red filter portions 15FR, a plurality of green filter portions 15FG, and a plurality of blue filter portions 15FB. In the following description, the red filter section 15FR, the green filter section 15FG, and the blue filter section 15FB are collectively referred to as the filter section 15F without particular distinction.

The plurality of filter portions 15F are two-dimensionally arranged in the in-plane direction. In this specification, the in-plane direction means the in-plane direction on the first surface of the circuit board 11 . Each filter section 15</b>F is provided above the light emitting element 20 . More specifically, the red filter section 15FR is provided above the light emitting element 20, the green filter section 15FG is provided above the light emitting element 20, and the blue filter section 15FB is provided above the light emitting element 20. ing. A sub-pixel 100R is composed of the red filter portion 15FR and the light-emitting element 20, a sub-pixel 100G is composed of the green filter portion 15FG and the light-emitting element 20, and a sub-pixel 100B is composed of the blue filter portion 15FB and the light-emitting element 20. ing.

The red filter portion 15FR transmits red light out of the white light emitted from the light emitting element 20, but absorbs light other than red light. The green filter portion 15FG transmits green light out of the white light emitted from the light emitting element 20, but absorbs light other than green light. The blue filter portion 15FB transmits blue light out of the white light emitted from the light emitting element 20, but absorbs light other than blue light.

The red filter portion 15FR includes, for example, a red color resist. The green filter portion 15FG includes, for example, a green color resist. The blue filter portion 15FB includes, for example, a blue color resist.

(Planarization layer 16)
The planarization layer 16 is provided on the first surface of the color filter 15 and planarizes the unevenness of the first surface of the color filter 15 . The planarization layer 16 contains, for example, an inorganic material or a polymeric resin. Examples of the inorganic material include materials similar to those of the first protective layer 13a. As the polymer resin, the same material as the polymer resin of the first protective layer 13a can be exemplified.

(Lens array 17)
The lens array 17 includes a plurality of lenses 17a. The plurality of lenses 17a are two-dimensionally arranged on the first surface of the planarization layer 16 in a prescribed arrangement pattern. One lens 17 a is provided for each light emitting element 20 . Each lens 17 a is provided above the light emitting element 20 . The lens 17a may be an on-chip microlens (OCL). The lens 17a collects the light emitted upward from the filter portion 15F in the front direction _DZ . The lens 17a has, for example, a convex curved surface protruding in the front direction _DZ . The convex curved surface is, for example, dome-shaped. Here, the dome shape includes shapes such as a substantially parabolic shape, a substantially hemispherical shape, and a substantially semiellipsoidal shape. It is preferable that the apex of the lens 17a approximately coincides with the center of the annular shape of the concave portion 110 in plan view.

The lens 17a includes, for example, an inorganic material or polymer resin that is transparent to visible light. Inorganic materials include, for example, silicon oxide (SiO _x ). Polymer resins include, for example, ultraviolet curable resins.

[Manufacturing method of display device 10]
An example of a method for manufacturing the display device 10 according to one embodiment will be described below.

(Formation process of circuit board 11)
First, an insulating layer 11b having a plurality of vias 11c therein is formed on the first surface of the substrate 11a. Next, after forming a photoresist layer on the insulating layer 11b by spin coating, for example, the resist layer is exposed and developed to pattern the resist layer. As a result, a plurality of openings are formed in portions of the resist layer that face the formation positions of the plurality of recesses 110 . Next, a plurality of recesses 110 are formed by etching the insulating layer 11b through the resist layer by dry etching, for example. As a method for forming the recess 110, the method for forming a recess described in Patent Document 1 may be used.

(Step of forming first electrode 21)
First, a metal layer and a metal oxide layer are sequentially formed on the first surface of the circuit board 11 by, for example, a sputtering method, and then the metal layer and the metal oxide layer are patterned by, for example, a photolithography technique and an etching technique. . Thereby, a plurality of first electrodes 21 are formed on the first surface of the circuit board 11 .

(Step of forming insulating layer 12)
Next, the insulating layer 12 is formed on the first surface of the circuit board 11 so as to cover the plurality of first electrodes 21 by, for example, a CVD (Chemical Vapor Deposition) method. Next, openings 12a are formed in portions of the insulating layer 12 located on the first surfaces of the first electrodes 21 by photolithography and dry etching, for example.

(Process of forming OLED layer 22)
Next, a hole transport layer, a red light emitting layer, a light emitting separation layer, a blue light emitting layer, a green light emitting layer, an electron transport layer, and an electron injection layer are formed on the first surface of the plurality of first electrodes 21 by vapor deposition, for example. and on the first surface of the insulating layer 12 in this order to form the OLED layer 22 .

(Step of forming second electrode 23)
Next, a second electrode 23 is formed on the first surface of the OLED layer 22 by vapor deposition or sputtering, for example. Thereby, a plurality of light emitting elements 20 are formed on the first surface of the circuit board 11 .

(Step of forming protective layer 13)
Next, the first protective layer 13a is formed on the first surface of the second electrode 23 by, for example, CVD or vapor deposition. Next, the second protective layer 13b is formed on the first surface of the first protective layer 13a by atomic layer deposition (ALD), for example. Thereby, the protective layer 13 including the first protective layer 13 a and the second protective layer 13 b is formed on the first surface of the second electrode 23 .

(Step of forming planarization layer 14)
Next, the planarization layer 14 is formed on the first surface of the second electrode 23 by, for example, CVD or vapor deposition.

(Formation process of color filter 15)
Next, a coloring composition for forming a green filter portion is applied onto the first surface of the flattening layer 14, irradiated with ultraviolet rays through a photomask for pattern exposure, and then developed to form a green filter portion 15FG. to form Next, a coloring composition for forming a red filter portion is applied onto the first surface of the flattening layer 14, irradiated with ultraviolet rays through a photomask for pattern exposure, and then developed to form a red filter portion 15FR. to form Next, a coloring composition for forming a blue filter portion is applied onto the first surface of the flattening layer 14, irradiated with ultraviolet rays through a photomask for pattern exposure, and then developed to form a blue filter portion 15FB. to form Thus, color filters 15 are formed on the first surface of planarization layer 14 .

(Step of forming planarization layer 16)
Next, a planarizing layer 16 is formed on the first surface of the color filter 15 by, for example, CVD or vapor deposition.

(Step of forming lens array 17)
Next, a lens material layer such as an acrylic resin is formed by applying a lens material such as an acrylic resin onto the first surface of the flattening layer 16 and curing it. Next, after the lens material layer is processed by, for example, photolithography technology and dry etching technology, it is reflowed and cured to form a plurality of lenses 17a.

[Effect]
In the display device 10 according to one embodiment, the insulating layer (lower layer) 11b has one annular concave portion 110 for each light emitting element 20 on the first surface, and the light emitting elements 20 are provided so as to follow the concave portion 110. It is For this reason, the first electrode 21 of the light emitting element 20 has one annular concave portion 210 . In the first electrode 21 having one annular concave portion 210, compared with the first electrode having one bowl-shaped concave portion, the depth of the concave portion 210 is not increased, and the inclination of the first electrode 21 is reduced. The surface area can be increased.
Therefore, in the step of forming the OLED layer 22, deterioration of throwing power of the OLED layer 22 (uniformity of thickness of the OLED layer 22) can be suppressed. Therefore, deterioration of characteristics such as luminance, chromaticity and heat resistance due to deterioration of the throwing power of the OLED layer 22 can be suppressed.
In addition, luminance can be improved without increasing the aperture ratio as compared with a display device including a first electrode having one bowl-shaped concave portion and a display device including a flat first electrode.

In the display device 10 according to one embodiment, since one annular concave portion 210 and one lens 17a are combined, the light reflected by the concave portion 210 is condensed in the front direction _DZ by the lens 17a. be able to. Therefore, since the light extraction efficiency can be further improved, the luminance can be further improved.

<2 Modifications>
(Modification 1)
As shown in FIGS. 5A and 5B , two recesses 110 having an annular shape in plan view may be provided for each light emitting element 20 . The two recesses 110 may be provided concentrically in plan view. The two concentric recesses 110 may share the geometric center of the light emitting element 20 in plan view as the center. The light emitting element 20 may be provided along the two recesses 110 . That is, the first electrode 21 may have two recesses 210 .

With the above configuration, the area of the slope of the recess 110, that is, the area of the slope of the first electrode 21 can be increased compared to the one embodiment. Therefore, the luminance of the display device 10 can be further improved.

Note that three or more recesses 110 that are concentric in plan view may be provided for each light emitting element 20, and the three or more recesses 110 may be concentrically provided in plan view. Three or more concentric recesses 110 may share the geometric center of the light emitting element 20 in plan view as the center. The light emitting element 20 may be provided along the three recesses 110 . That is, the first electrode 21 may have three recesses 210 .

(Modification 2)
As shown in FIGS. 6A and 6B, one concave portion (first concave portion) 110 having an annular shape in plan view and one concave portion (second concave portion) 110a having a circular shape (dot shape) in plan view. may be provided for each light emitting element 20 . The recess 110 a may be provided inside the recess 110 .

The concave portion 110a may have a bowl shape. The bowl may have a flat bottom and sides. The side surface may be flat, or may be a convex or concave curved surface. The bowl shape with flat bottom and sides may be a frustum shape. The frustum may be, for example, a truncated cone, an elliptical truncated pyramid, a truncated pyramid (eg, a square truncated pyramid or a hexagonal truncated pyramid). The bowl shape may be a concave surface shape. The concave curved surface shape may be, for example, a substantially paraboloid shape, a substantially semispherical shape, a substantially semiellipsoidal shape, or the like.

The light emitting element 20 may be provided along one recess 110 and one recess 110a. That is, the first electrode 21 may have one recess 210 and one recess 210a.

The above configuration can be easily provided even when the size of the sub-pixel 100 is small and it is difficult to provide a plurality of annular concave portions 110 for each light emitting element 20 . Therefore, even when the size of the sub-pixel 100 is small, the area of the slope of the first electrode 21 can be easily increased.

As described above, when one concave portion 110 having an annular shape in plan view and one concave portion 110a having a circular shape in plan view are provided for each light emitting element 20, may be provided with a first lens and a second lens. The first lens is a lens with a convex curved surface and may have the same shape as the concave portion 110 in plan view, that is, an annular shape. The second lens is a lens with a convex curved surface and may have the same shape as the concave portion 110a in plan view, that is, a circular shape. The first lens may be provided above the recess 110 . The second lens may be provided above the recess 110a. Thereby, light can be efficiently incident on the plurality of lenses 17a.

(Modification 3)
As shown in FIGS. 7A and 7B , a plurality of recesses 110b having a circular shape in plan view may be provided for each light emitting element 20 . The plurality of recesses 110b may be two-dimensionally arranged in a prescribed arrangement pattern on the first surface of the insulating layer 11b. The shape of the recess 110b is the same as that of the recess 110a in the second modification. The light emitting element 20 may be provided along the plurality of recesses 110b. That is, the first electrode 21 may have a plurality of recesses 210b.

In the above configuration, as the number of recesses 110b is increased, the area of the slopes of the recesses 110b, that is, the slope of the first electrode 21 can be increased. The lower limit of the number of recesses 110b is, for example, 2 or more, 3 or more, 4 or more, or 5 or more. The upper limit of the number of recesses 110b is not particularly limited, but is, for example, 10 or less.

When a plurality of bowl-shaped recesses 110b are provided for each light emitting element 20, a plurality of lenses 17a may be provided above the plurality of recesses 110b. The lens 17a may have a convex curved surface such as a dome shape. The width of the plurality of recesses 110 may vary according to the width of the lens 17a. Thereby, light can be efficiently incident on the plurality of lenses 17a.

(Modification 4)
When a plurality of recesses 110 are provided for each light emitting element 20 (see FIG. 5A, for example), the depths of the plurality of recesses 110 may be different. That is, when a plurality of recesses 210 are provided for each first electrode 21, the depths of the plurality of recesses 210 may be different. Thereby, the traveling direction of the light emitted from the light emitting element 20 can be controlled.

For example, when two recesses 110 having an annular shape in plan view are provided for each light emitting element 20 (see, for example, FIG. 5A), as shown in FIG. The depth of the concave portion 110 may be deeper than the depth of the concave portion 110 provided on the outside. That is, of the two recesses 210 of the first electrode 21, the recess 210 provided inside may be deeper than the recess 210 provided outside. Alternatively, as shown in FIG. 8B, the depth of the recess 110 provided on the inner side of the two recesses 110 may be shallower than the depth of the recess 110 provided on the outer side. That is, the depth of the recess 210 provided on the inner side of the two recesses 210 of the first electrode 21 may be shallower than the depth of the recess 210 provided on the outer side.

For example, if the depth of the concave portion 110 provided on the outer side of the two concave portions 110 is greater than the depth of the concave portion 110 provided on the inner side, the traveling direction of the reflected light is directed toward the inside of the sub-pixel 100. , the amount of reflected light entering the lens 17a of the adjacent sub-pixel 100 can be reduced.

For example, one recess (first recess) 110 having an annular shape in plan view and one recess (second recess) 110a having a circular shape in plan view are provided for each light emitting element 20. 6A, the depth of the inner recess 110a may be greater than the depth of the outer recess 110, as shown in FIG. 9A. That is, in the first electrode 21, the depth of the recess 210a on the inner side may be deeper than the depth of the recess 210 on the outer side. Alternatively, the depth of the inner recess 110 a may be shallower than the depth of the outer recess 110 . That is, in the first electrode 21, the depth of the recess 210a on the inner side may be shallower than the depth of the recess 210 on the outer side. In this case, the recess 110a and the recess 210a may be bowl-shaped with a flat bottom as shown in FIG. 9A, or bowl-shaped with a concave curved bottom as shown in FIG. 9B. may

For example, if the depth of the recess 110 provided on the outer side of the two recesses 110 and 110a is greater than the depth of the recess 110a provided on the inner side, the traveling direction of the reflected light is further directed toward the inside of the sub-pixel 100. Therefore, the amount of reflected light entering the lens 17a of the adjacent sub-pixel 100 can be reduced.

For example, when a plurality of recesses 110 and one recess 110a are provided for each light emitting element 20, the depths of the recesses 110 may be different, or the depths of the recesses 110 may be different, Moreover, the depth of the plurality of recesses 110 and the depth of the single recess 110a may be different. That is, in the first electrode 21, the plurality of recesses 210 may have different depths, or the plurality of recesses 210 may have different depths, and the plurality of recesses 210 and one recess 210a may have different depths. can be different.

For example, when a plurality of recesses 110b are provided for each light emitting element 20 (see FIG. 7A, for example), the depths of the plurality of recesses 110b may be different. That is, in the first electrode 21, the recesses 210b may have different depths.

(Modification 5)
When a plurality of recesses 110 are provided for each light emitting element 20 (see FIG. 5A, for example), the widths of the plurality of recesses 110 may be different. That is, when a plurality of recesses 210 are provided for each first electrode 21, the widths of the plurality of recesses 210 may be different.

For example, when two annular recesses 110 are provided for each light emitting element 20 (see, for example, FIG. 5A), the width of the recess 110 provided on the inner side of the two recesses 110 is the width of the recess 110 provided on the outer side. It may be wider than the width of the recess 110 formed. That is, the width of the concave portion 210 provided on the inner side of the two concave portions 210 of the first electrode 21 may be wider than the width of the concave portion 210 provided on the outer side. Alternatively, the width of the recess 110 provided on the inner side of the two recesses 110 may be narrower than the width of the recess 110 provided on the outer side. In other words, the width of the recess 210 provided on the inner side of the two recesses 210 of the first electrode 21 may be narrower than the width of the recess 210 provided on the outer side.

When a plurality of annular recesses 110 are provided for each light emitting element 20, a plurality of lenses 17a may be provided above the plurality of recesses 110, respectively. Lens 17a may have a toric shape. The width of the plurality of recesses 110 may vary according to the width of the lens 17a. Thereby, light can be efficiently incident on the plurality of lenses 17a.

For example, when a plurality of recesses 110 and one recess 110a are provided for each light emitting element 20, the widths of the recesses 110 may be different, the widths of the recesses 110 may be different, and The width of the plurality of recesses 110 and the width of one recess 110a may be different. That is, in the first electrode 21, the plurality of recesses 210 may have different widths, or the plurality of recesses 210 may have different widths, and the plurality of recesses 210 and one recess 210a may have different widths. good.

For example, when a plurality of recesses 110b are provided for each light emitting element 20 (see FIG. 7A, for example), the widths of the plurality of recesses 110b may be different. That is, in the first electrode 21, the widths of the recesses 210b may be different.

(Modification 6)
In the above embodiment, the example in which the via 11c is connected to the flat portion of the first electrode 21 where the recess 210 is not provided has been described, but the connection form of the via 11c is limited to this example. not a thing For example, as shown in FIG. 10, the insulating layer 11b further includes a plurality of conductive layers 21e inside, the conductive layers 21e are in contact with the bottom surface (second surface) of the recess 210, and the vias 11c are connected to the conductive layers 21e. may be connected to the wiring 11d. The conductive layer 21e is, for example, wiring or an electrode.

(Modification 7)
In the above embodiment, the lens 17a has a convex curved surface such as a dome shape, but the shape of the lens 17a is not limited to this. For example, as shown in FIG. 11, the lens 17a may have the same shape as the recess 110 of the insulating layer 11b (that is, the same shape as the recess 210 of the first electrode 21) in plan view. More specifically, the lens 17a may have an annular shape in plan view. The lens 17a may be a lens having a convex curved surface. The resulting cross-sectional shape may be arcuate. Here, the arch shape includes a substantially circular arc shape, a substantially elliptical arc shape and a substantially parabolic shape. Since the lens 17a has an annular shape as described above, it is possible to reduce light entering the adjacent sub-pixels 100 and suppress color mixture.

When a plurality of concave portions 110 are provided for each light emitting element 20 (see, for example, FIG. 5A), the display device 10 may include a plurality of lenses as many as the concave portions 110 . Each of the plurality of lenses may have the same shape as the plurality of recesses 110 (that is, the same shape as the recesses 210 of the first electrode 21) in plan view.

When one or more recesses 110 and one recess 110a are provided for each light emitting element 20 (see, for example, FIG. 6A), the display device 10 has the same number of recesses 110 and one or more recesses 110a. A plurality of first lenses and one second lens may be provided. Each of the one or more first lenses has the same shape as the one or more recesses 110 (that is, the same shape as the one or more recesses 210 of the first electrode 21) in plan view. Also, the second lens may have the same shape as one recess 110a (that is, the same shape as one recess 210a of the first electrode 21) in plan view.

When a plurality of concave portions 110b are provided for each light emitting element 20 (see, for example, FIG. 7A), the display device 10 may include a plurality of lenses as many as the concave portions 110b. Each of the plurality of lenses may have the same shape as the plurality of recesses 110b (that is, the same shape as the recesses 210b of the first electrode 21) in plan view.

(Modification 8)
Although the display device 10 includes the planarization layer 14 and the color filter 15 in the above embodiment, the planarization layer 14 may have the function of the color filter 15 .
More specifically, for example, the display device 10 may have the color filter 15 directly on the first surface of the protective layer 13 . In this case, since the distance from the light emitting element 20 to the lens 17a can be shortened, the amount of light leaking to the adjacent sub-pixel 100 can be reduced.

(Modification 9)
The display device 10 may have a filling resin layer and a counter substrate on the lens array 17 in this order. The filling resin layer fills the gap between the lens array 17 and the counter substrate and bonds the lens array 17 and the counter substrate. The filled resin layer contains, for example, at least one selected from the group consisting of thermosetting resins and UV-curable resins.

The counter substrate is provided on the first surface of the filled resin layer and faces the circuit board 11 . The counter substrate and the filling resin layer seal the light emitting element 20, the color filter 15, and the like. The counter substrate includes a material such as glass that is transparent to each color of light emitted from the color filter 15 .

(Modification 10)
In the above embodiment, an example in which the display device 10 is colored by combining the white OLED element and the color filter 15 is described, but the coloration method is not limited to this. For example, the color scheme may be a scheme in which a light-emitting element that emits red light, a light-emitting element that emits green light, and a light-emitting element that emits blue light are provided.

(Other modifications)
As described above, the embodiment of the present disclosure and its modification have been specifically described, but the present disclosure is not limited to the above-described embodiment and its modification. is possible.

For example, the configurations, methods, steps, shapes, materials, numerical values, etc. given in the above-described embodiment and modifications thereof are merely examples, and if necessary, different configurations, methods, steps, shapes, materials and A numerical value or the like may be used.

For example, the configurations, methods, steps, shapes, materials, numerical values, etc. of the above embodiment and its modifications can be combined with each other without departing from the gist of the present disclosure.

For example, the materials exemplified in the above one embodiment and its modifications can be used singly or in combination of two or more unless otherwise specified.

In addition, the present disclosure can also employ the following configuration.
(1)
a plurality of light emitting elements arranged two-dimensionally;
and a lower layer provided under the plurality of light emitting elements,
the lower layer has one or more recesses for each light emitting element;
The light emitting element is provided along the recess,
When the lower layer has one recess for each light emitting element, one recess is cut along a plane that passes through the geometric center of the light emitting element in plan view and is parallel to the thickness direction of the display device. A display device in which the cross-sectional shape obtained by the above includes a plurality of concave portions.
(2)
The display device according to (1), wherein the concave portion has an annular shape in plan view.
(3)
the lower layer has a plurality of recesses for each light emitting element,
The display device according to (1), wherein the plurality of recesses are concentric in plan view.
(4)
the lower layer has a plurality of recesses for each light emitting element,
The display device according to (1), wherein each recess has a bowl shape.
(5)
the lower layer has a plurality of recesses for each light emitting element,
According to (1), the plurality of recesses includes a first recess having an annular shape in plan view, and a second recess provided inside the first recess and having a dot shape in plan view. display device.
(6)
the lower layer has a plurality of recesses for each light emitting element,
The display device according to (1), wherein the plurality of recesses have different widths.
(7)
the lower layer has a plurality of recesses for each light emitting element,
The display device according to (1), wherein the plurality of recesses have different depths.
(8)
a protective layer covering the plurality of light emitting elements;
and a planarization layer provided on the protective layer,
The display device according to any one of (1) to (7), wherein the planarization layer functions as a color filter.
(9)
a protective layer covering the plurality of light emitting elements;
a planarization layer provided on the protective layer;
The display device according to any one of (1) to (7), further comprising a color filter provided on the planarization layer.
(10)
Further comprising a plurality of lenses provided above the plurality of light emitting elements,
The display device according to any one of (1) to (9), wherein one or more lenses are provided for each light emitting element.
(11)
The display device according to (10), wherein the concave portion and the lens have the same shape in plan view.
(12)
The display device according to (10), wherein the concave portion and the lens have an annular shape in the plan view.
(13)
The display device according to any one of (1) to (12), wherein each light emitting element includes, in order, a first electrode, an organic layer including a light emitting layer, and a second electrode.
(14)
An electronic device comprising the display device according to any one of (1) to (13).

<3 Reference example>
Hereinafter, the present disclosure will be specifically described with reference examples, but the present disclosure is not limited to these reference examples. FIG. 12A is a diagram showing cross-sectional shapes of first electrodes 21 of Comparative Examples 1A, 1B, 1C, 2A, 2B, and 2C. FIG. 12B is a diagram showing the cross-sectional shape of the first electrode 21 of Reference Examples 1A, 1B, 1C, 2A, 2B, and 2C. FIG. 12C is a diagram showing the cross-sectional shape of the first electrode 21 of Reference Examples 3A, 3B, 3C, 4A, 4B, and 4C.

(Comparative Examples 1A, 1B, 1C)
The surface area S _A of the first electrode 21 having one bowl-shaped recess 210 was obtained. The details of the configuration of the bowl-shaped concave portion 210 are shown below.
Shape of concave portion 210 in plan view: circular shape (diameter φ=2.29 μm)
Cross-sectional shape of concave portion 210: Trapezoid (see FIG. 12A)
Depth D of recess 210: 100 μm, 200 μm, 300 μm
The inclination angle θ of the inclined surface of the concave portion 210: 45 degrees Based on the flat surface area _S0 of the first electrode 21, the area increase rate R _A of the surface area S _A of the first electrode 21 having the above configuration was obtained. . The results are shown in Table 1.

(Comparative Examples 2A, 2B, 2C)
The surface area S _A of the first electrode 21 having one bowl-shaped recess 210 was determined. The details of the configuration of the bowl-shaped concave portion 210 are shown below.
Shape of concave portion 210 in plan view: circular shape (diameter φ=1.85 μm)
Cross-sectional shape of concave portion 210: Trapezoid (see FIG. 12A)
Depth D of recess 210: 100 μm, 200 μm, 300 μm
The inclination angle θ of the inclined surface of the concave portion 210: 45 degrees Based on the flat surface area _S0 of the first electrode 21, the area increase rate R _A of the surface area S _A of the first electrode 21 having the above configuration was obtained. . The results are shown in Table 1.

(Reference Examples 1A, 1B, 1C)
The surface area S _B of the first electrode 21 having one annular recess 210 was obtained. The details of the configuration of the annular recess 210 are shown below.
Shape of concave portion 210 in plan view: circular ring (circular outer diameter φ=2.29 μm)
Cross-sectional shape of concave portion 210: Trapezoid (see FIG. 12B)
Depth D of recess 210: 100 μm, 200 μm, 300 μm
Inclined angle θ of inclined surface of recess 210: 45 degrees Based on the surface area S0 of the flat first electrode 21, the area increase rate _RB of the surface area _SB of the first electrode 21 having the above configuration was obtained. The results are shown in Table 2.

(Reference Examples 2A, 2B, 2C)
The surface area S _B of the first electrode 21 having one annular recess 210 was obtained. The details of the configuration of the annular recess 210 are shown below.
Shape of concave portion 210 in plan view: circular ring (circular outer circumference diameter φ=1.85 μm)
Cross-sectional shape of concave portion 210: Trapezoid (see FIG. 12B)
Depth D of recess 210: 100 μm, 200 μm, 300 μm
Inclination angle θ of the inclined surface of the concave portion 210: 45 degrees Based on the flat surface area _S0 of the first electrode 21, the area increase rate R _B of the surface area S _B of the first electrode 21 having the above configuration was obtained. . The results are shown in Table 2.

(Reference Examples 3A, 3B, 3C)
The surface area _SC of the first electrode 21 having two annular recesses 210 was obtained. The details of the configuration of the annular recess 210 are shown below.
Shape of concave portion 210 in plan view: circular ring (diameter φ of outer circumference of outer circular ring = 2.29 μm)
Cross-sectional shape of concave portion 210: Trapezoid (see FIG. 12C)
Depth D of recess 210: 100 μm, 200 μm, 300 μm
Inclination angle θ of the inclined surface of the concave portion 210: 45 degrees Based on the flat surface area _S0 of the first electrode 21, the area increase rate _Rc of the surface area _Sc of the first electrode 21 having the above configuration was obtained. . The results are shown in Table 3.

(Reference Examples 4A, 4B, 4C)
The surface area _SC of the first electrode 21 having two annular recesses 210 was obtained. The details of the configuration of the annular recess 210 are shown below.
Shape of concave portion 210 in plan view: circular ring (diameter φ of outer circumference of outer circular ring = 1.85 µm)
Cross-sectional shape of concave portion 210: Trapezoid (see FIG. 12C)
Depth D of recess 210: 100 μm, 200 μm, 300 μm
Inclination angle θ of the inclined surface of the concave portion 210: 45 degrees Based on the flat surface area _S0 of the first electrode 21, the area increase rate _Rc of the surface area _Sc of the first electrode 21 having the above configuration was obtained. . The results are shown in Table 3.

Compared to the first electrode 21 having one bowl-shaped recess 210, the first electrode 21 having one or two annular recesses 210 does not increase the depth of the recess 210, and the first electrode 21 has It can be seen that the area of the electrode 21 can be increased.

<5 Application example>
(Electronics)
The display device 10 according to the above embodiment and its modification can be provided in various electronic devices. The display device 10 according to the above-described embodiment and its modification is required to have a high resolution, such as an electronic viewfinder of a video camera or a single-lens reflex camera, or a head-mounted display, and is enlarged and used near the eyes. suitable for

(Specific example 1)
13A and 13B show an example of the appearance of the digital still camera 310. FIG. This digital still camera 310 is of an interchangeable single-lens reflex type, and has an interchangeable photographing lens unit (interchangeable lens) 312 in approximately the center of the front of a camera main body (camera body) 311, and on the left side of the front. It has a grip portion 313 for a photographer to hold.

A monitor 314 is provided at a position shifted to the left from the center of the back surface of the camera body 311 . An electronic viewfinder (eyepiece window) 315 is provided above the monitor 314 . By looking through the electronic viewfinder 315, the photographer can view the optical image of the subject guided from the photographing lens unit 312 and determine the composition. The electronic viewfinder 315 includes any one of the display devices 10 according to the above embodiment and variations thereof.

(Specific example 2)
FIG. 14 shows an example of the appearance of the head mounted display 320. As shown in FIG. The head-mounted display 320 has, for example, ear hooks 322 on both sides of an eyeglass-shaped display 321 to be worn on the user's head. The display unit 321 includes any one of the display devices 10 according to the above embodiment and its modification.

(Specific example 3)
FIG. 15 shows an example of the appearance of the television device 330. As shown in FIG. This television device 330 has, for example, a video display screen portion 331 including a front panel 332 and a filter glass 333. This video display screen portion 331 is a display device according to the above embodiment and its modification. 10.

REFERENCE SIGNS LIST 10 display device 11 circuit board 11a substrate 11b insulating layer 11c via 11d wiring 12 insulating layer 12a opening 13 protective layer 13a first protective layer 13a second protective layer 14 flattening layer 15 color filter 15FR red filter section 15FG green filter section 15FB blue filter section 16 planarization layer 17 lens array 17a lens 20 light emitting element 21 first electrode 21e conductive layer 22 OLED layer 23 second electrode R1 display area R2 peripheral area 100R, 100G, 100B sub-pixel 101 pad section 110, 110a, 110b recessed portion 111 bottom portion 112a inner peripheral wall portion 112b outer peripheral wall portion 210, 210a, 210b recessed portion 310 digital still camera (electronic device)
320 head mounted display (electronic equipment)
330 Television equipment (electronic equipment)
D _Z front direction D _X horizontal direction D _Y vertical direction

Claims (14)

1. a plurality of light emitting elements arranged two-dimensionally;
   and a lower layer provided under the plurality of light emitting elements,
   the lower layer has one or more recesses for each light emitting element;
   The light emitting element is provided along the recess,
   When the lower layer has one recess for each light emitting element, one recess is cut along a plane that passes through the geometric center of the light emitting element in plan view and is parallel to the thickness direction of the display device. A display device in which the cross-sectional shape obtained by the above includes a plurality of concave portions.
2. The display device according to claim 1, wherein the concave portion has an annular shape in plan view.
3. the lower layer has a plurality of recesses for each light emitting element,
   2. The display device according to claim 1, wherein the plurality of recesses are concentric in plan view.
4. the lower layer has a plurality of recesses for each light emitting element,
   2. The display device according to claim 1, wherein each recess has a bowl shape.
5. the lower layer has a plurality of recesses for each light emitting element,
   2. The plurality of recesses according to claim 1, wherein the plurality of recesses includes a first recess having an annular shape in plan view, and a second recess provided inside the first recess and having a dot shape in plan view. display device.
6. the lower layer has a plurality of recesses for each light emitting element,
   2. The display device according to claim 1, wherein the plurality of recesses have different widths.
7. the lower layer has a plurality of recesses for each light emitting element,
   2. The display device according to claim 1, wherein the plurality of recesses have different depths.
8. a protective layer covering the plurality of light emitting elements;
   and a planarization layer provided on the protective layer,
   2. The display device according to claim 1, wherein the planarization layer functions as a color filter.
9. a protective layer covering the plurality of light emitting elements;
   a planarization layer provided on the protective layer;
   The display device of Claim 1, further comprising: a color filter provided on the planarization layer.
10. Further comprising a plurality of lenses provided above the plurality of light emitting elements,
    2. The display device according to claim 1, wherein one or more lenses are provided for each light emitting element.
11. 11. The display device according to claim 10, wherein the concave portion and the lens have the same shape in plan view.
12. 11. The display device according to claim 10, wherein the concave portion and the lens have an annular shape in plan view.
13. 2. The display device according to claim 1, wherein each light-emitting element includes, in order, a first electrode, an organic layer including a light-emitting layer, and a second electrode.
14. An electronic device comprising the display device according to claim 1.

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