WO2024111104A1

WO2024111104A1 - Display device

Info

Publication number: WO2024111104A1
Application number: PCT/JP2022/043436
Authority: WO
Inventors: 敬之主藤
Original assignee: シャープディスプレイテクノロジー株式会社
Priority date: 2022-11-25
Filing date: 2022-11-25
Publication date: 2024-05-30

Abstract

A display device (1) comprises: light emitting elements (5R·5G·5B) provided in respective ones of a plurality of sub-pixels (RSUB·GSUB·BSUB) and including a lower electrode (22), a hole transport layer (25), light emitting layers (8R·8G·8B), and a first upper electrode layer (28) in this order from the side of a substrate (2); and non-light emitting charge-transfer elements (6R·6G·6B) provided in respective ones of a plurality of dummy sub-pixels (DRSUB·DGSUB·SBSUB) and including the lower electrode (22), the hole transport layer (25), the light emitting layers (8R·8G·8B), and the second upper electrode layer (28a) in this order from the substrate (2) side. The non-light emitting charge-transfer elements (6R·6G·6B) comprise a resistance adjustment layer having a resistivity higher than that of the first upper electrode layer (28) and less than or equal to 1×10⁹Ω·cm between a first surface (M1), which is a surface on the light emitting layer (8R·8G·8B) side of the hole transport layer (25), and a second surface (M2), which is a surface on the opposite side of the second upper electrode layer (28a) from the substrate (2).

Description

Display device

This disclosure relates to a display device.

In recent years, various display devices equipped with light-emitting elements have been developed, and display devices equipped with OLEDs (Organic Light Emitting Diodes) or QLEDs (Quantum dot Light Emitting Diodes) in particular have attracted a great deal of attention because of their ability to achieve low power consumption, thinness, and high image quality.

In the field of these display devices, a charge transfer layer (at least one of a hole injection layer and a hole transport layer, or at least one of an electron injection layer and an electron transport layer) is often formed over the entire display area between the lower electrode and the light-emitting layer of the light-emitting element.

Patent document 1 describes a display device in which a hole injection layer and a hole transport layer are formed over the entire display area as charge transfer layers provided between the lower electrode and the light-emitting layer of an OLED.

Japanese Patent Publication "JP2014-164829"

As in the display device described in Patent Document 1, when at least one of a hole injection layer and a hole transport layer is formed over the entire display area as a charge transfer layer provided between the lower electrode and the light-emitting layer of the light-emitting element, there is a problem that bright lines are visible around the edges of the display area.

Such a problem also occurs when at least one of an electron injection layer and an electron transport layer is formed over the entire display area as a charge transfer layer provided between the lower electrode and the light-emitting layer of the light-emitting element, resulting in bright lines being visible around the edges of the display area.

One aspect of the present disclosure has been made in consideration of the above problems, and aims to provide a display device that suppresses the phenomenon in which light emitting elements provided around the edges of a display area emit light brighter than intended, causing bright lines to become visible, even when a charge transfer layer provided between a lower electrode and a light emitting layer of the light emitting element is formed over the entire display area.

In order to solve the above problems, the display device of the present disclosure has:
A substrate;
a display region on the substrate, the display region including a plurality of pixels each including a plurality of sub-pixels;
a non-display area on the substrate, the non-display area including a plurality of dummy sub-pixels provided along an edge of the display area and being continuous with the display area;
A plurality of lower electrodes provided in each of the display area and the non-display area;
a charge transport layer which is a single continuous layer provided across the display area and the non-display area;
A first upper electrode layer provided in the display area;
A second upper electrode layer provided in the non-display area;
a light-emitting element provided in each of the plurality of sub-pixels, the light-emitting element including, in this order from the substrate side, the lower electrode, the charge transfer layer, a light-emitting layer, and the first upper electrode layer;
a non-light-emitting charge transfer element provided in each of the plurality of dummy sub-pixels, the non-light-emitting charge transfer element including, in this order from the substrate side, the lower electrode, the charge transfer layer, a light-emitting layer, and the second upper electrode layer;
The non-light-emitting charge transfer element includes a resistance adjustment layer between a first surface of the charge transfer layer facing the light-emitting layer and a second surface of the second upper electrode layer facing away from the substrate, the resistance adjustment layer having a resistivity higher than that of the first upper electrode layer and being 1 x ¹⁰⁹ Ω-cm or less.

One aspect of the present disclosure has been made in consideration of the above problems, and provides a display device that suppresses the phenomenon in which light emitting elements provided around the edges of the display area emit light brighter than intended, causing bright lines to be visible, even when a charge transfer layer provided between a lower electrode and a light emitting layer of the light emitting element is formed over the entire display area.

1 is a plan view showing a schematic configuration of a display device according to a first embodiment. 2 is a cross-sectional view showing a schematic configuration of a substrate provided in the display device of the first embodiment shown in FIG. 1. 1 is a cross-sectional view showing a schematic configuration of a light-emitting element provided in a display region and a non-light-emitting charge transfer element provided in a non-display region of the display device of embodiment 1. FIG. 4 is a circuit diagram of the vicinity of the boundary between the display area and the non-display area of the display device of the first embodiment shown in FIG. 3. FIG. 11 is a cross-sectional view showing a schematic configuration of a display device as a comparative example in which light-emitting elements provided around the edge of a display area emit light brighter than intended, causing visible bright lines. 6 is a circuit diagram for explaining the reason why bright lines are visible around the edges of the display area of the display device that is the comparative example shown in FIG. 5 . 10 is a cross-sectional view showing a schematic configuration of a light-emitting element provided in a display region and a non-light-emitting charge transfer element provided in a non-display region of a display device of embodiment 2. FIG. 11 is a cross-sectional view showing a schematic configuration of a light-emitting element provided in a display region and a non-light-emitting charge transfer element provided in a non-display region of a display device of embodiment 3. FIG. 11 is a cross-sectional view showing a schematic configuration of a light-emitting element provided in a display region and a non-light-emitting charge transfer element provided in a non-display region of a display device of embodiment 4. FIG. 13 is a cross-sectional view showing a schematic configuration of a light-emitting element provided in a display region and a non-light-emitting charge transfer element provided in a non-display region of a display device of embodiment 5. FIG. 11 is a circuit diagram of the vicinity of the boundary between the display area and the non-display area of the display device of the fifth embodiment shown in FIG. 10. FIG. 11 is a cross-sectional view showing a schematic configuration of a display device as another comparative example in which light-emitting elements provided around the edge of a display area emit light brighter than intended, resulting in visible bright lines. 13 is a circuit diagram for explaining the reason why bright lines are visible around the edges of the display area of the display device of the other comparative example shown in FIG. 12. FIG. 13 is a cross-sectional view showing a schematic configuration of a light-emitting element provided in a display region and a non-light-emitting charge transfer element provided in a non-display region of a display device of embodiment 6. FIG. 13 is a cross-sectional view showing a schematic configuration of a light-emitting element provided in a display region and a non-light-emitting charge transfer element provided in a non-display region of the display device of embodiment 7. FIG. 13 is a cross-sectional view showing a schematic configuration of a light-emitting element provided in a display region and a non-light-emitting charge transfer element provided in a non-display region of the display device of embodiment 8. FIG. FIG. 13 is a plan view showing a schematic configuration of a display device according to a ninth embodiment.

The embodiment of the present disclosure will be described below with reference to Figs. 1 to 17. For ease of explanation, configurations having the same functions as those described in specific embodiments will be denoted by the same reference numerals, and descriptions thereof may be omitted.

[Embodiment 1]
FIG. 1 is a plan view showing a schematic configuration of a display device 1 according to the first embodiment.

1, the display device 1 includes a substrate 2, a display area DA on the substrate 2 including a plurality of pixels PIX, each of which includes a red subpixel RSUB, a green subpixel GSUB, and a blue subpixel BSUB, a frame area GA on the substrate 2 provided outside the display area DA, and a non-display area (first non-display area) NDA1 on the substrate 2 which is a part of the frame area GA and is continuous with the display area DA, and which includes a plurality of dummy sub-pixels (see FIG. 3) provided along an end DAE of the display area DA. Although not shown, the frame area GA outside the non-display area NDA1 is provided with a terminal section, a drive circuit, etc. In this embodiment, an example will be described in which one pixel PIX is composed of a red subpixel RSUB, a green subpixel GSUB, and a blue subpixel BSUB, but this is not limited to this. For example, one pixel PIX may include subpixels of other colors in addition to the red subpixel RSUB, the green subpixel GSUB, and the blue subpixel BSUB.

As shown in FIG. 1, since the non-display area NDA1 is included in the frame area GA, in order to realize a narrow frame of the display device 1, it is preferable that the non-display area NDA1 is not made wider than necessary. Therefore, when the shape of the pixel PIX is rectangular as in this embodiment, it is preferable that the width of the non-display area NDA1 is formed to be equal to or less than the length of the diagonal of the pixel PIX. In this embodiment, in order to make the width of the non-display area NDA1 equal to or less than the length of the diagonal of the pixel PIX, the width H1 of the rectangular right non-display area NDA1 shown in FIG. 1 and the width H2 of the rectangular upper non-display area NDA1 shown in FIG. 1 and the width H2 of the rectangular lower non-display area NDA1 shown in FIG. 1 are each formed to be equal to or less than the width of the diagonal of the pixel PIX, and the four corners of the non-display area NDA1 shown in FIG. 1, i.e., the rectangular The width H3 of the irregular part (upper right irregular part) connecting the upper non-display area and the rectangular right non-display area, the width H3 of the irregular part (lower right irregular part) connecting the rectangular right non-display area and the rectangular lower non-display area, the width H3 of the irregular part (lower left irregular part) connecting the rectangular lower non-display area and the rectangular left non-display area, and the width H3 of the irregular part (upper left irregular part) connecting the rectangular left non-display area and the rectangular upper non-display area are each formed with the length of the diagonal of the pixel PIX as an example, but are not limited to this. For example, the width of the non-display area NDA1 may be formed to be 50 μm or less, and is preferably formed to be 5 μm or more and 50 μm or less. By setting the width of the non-display area NDA1 to the above-mentioned range, it is possible to realize a narrow frame of the display device 1, and it is possible to realize a display device 1 that suppresses the light emitting element provided around the end DAE of the display area DA from emitting light brighter than the intended brightness and causing a bright line to be visible.

In this embodiment, the case where the non-display area NDA1 is arranged to surround the display area DA is described as an example, but this is not limited thereto, and the non-display area NDA1 may be arranged to surround at least a portion of the display area DA. For example, the non-display area NDA1 may be arranged to surround only the four corners of the display area DA shown in FIG. 1, or may be arranged to surround at least one of the four sides excluding the four corners of the display area DA shown in FIG. 1.

FIG. 2 is a cross-sectional view showing the schematic configuration of the substrate 2 provided in the display device 1 shown in FIG. 1.

As shown in FIG. 2, in the substrate 2 including the transistor TR1 provided in the display device 1, a barrier layer 3 and a thin-film transistor layer 4 including the transistor TR1 are provided on the support substrate 12 in this order from the support substrate 12 side. In addition, an edge cover layer 23 that covers the lower electrode 22 and the edge portion of the lower electrode 22 is provided on the surface of the substrate 2 including the transistor TR1 in the display area DA and non-display area NDA1 of the display device 1.

The support substrate 12 may be, for example, a resin substrate made of a resin material such as polyimide, or a glass substrate. In this embodiment, in order to make the display device 1 a flexible display device, a case in which a resin substrate made of a resin material such as polyimide is used as the support substrate 12 will be described as an example, but this is not limited to this. If the display device 1 is a non-flexible display device, a glass substrate can be used as the support substrate 12.

The barrier layer 3 is a layer that prevents foreign substances such as water and oxygen from penetrating the transistor TR1 and the light-emitting elements of each color described below, and can be composed of, for example, a silicon oxide film, a silicon nitride film, or a silicon oxynitride film, or a laminate film of these, formed by a chemical vapor deposition (CVD) method.

The transistor TR1 portion of the thin-film transistor layer 4 including the transistor TR1 includes the semiconductor film SEM and doped semiconductor films SEM' and SEM'', the inorganic insulating film 16, the gate electrode G, the inorganic insulating film 18, the inorganic insulating film 20, the source electrode S and the drain electrode D, and the planarization film 21, and the portion of the thin-film transistor layer 4 including the transistor TR1 other than the transistor TR1 portion includes the inorganic insulating film 16, the inorganic insulating film 18, the inorganic insulating film 20, and the planarization film 21.

The semiconductor films SEM, SEM', and SEM'' may be made of, for example, low-temperature polysilicon (LTPS) or an oxide semiconductor (for example, an In-Ga-Zn-O-based semiconductor). In this embodiment, the case where the transistor TR1 has a top-gate structure is described as an example, but this is not limiting, and the transistor TR1 may have a bottom-gate structure.

The gate electrode G and the source and drain electrodes S and D can be formed of a single layer or a multilayer film of a metal containing at least one of aluminum, tungsten, molybdenum, tantalum, chromium, titanium, and copper, for example.

Inorganic insulating film 16, inorganic insulating film 18, and inorganic insulating film 20 can be composed of, for example, a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or a laminate film of these films formed by a chemical vapor deposition (CVD) method.

The planarization film 21 can be made of a coatable organic material such as polyimide or acrylic.

The insulating edge cover layer 23 that covers the edge of the lower electrode 22 can be formed, for example, by applying an organic material such as polyimide or acrylic and then patterning it using a photolithography method.

As shown in FIG. 2, a control circuit including a transistor TR1 that controls each of the multiple lower electrodes 22 is provided in the thin-film transistor layer 4 that includes the transistor TR1.

FIG. 3 is a cross-sectional view showing a schematic configuration of a red light-emitting element 5R, a green light-emitting element 5G, and a blue light-emitting element 5B provided in the display area DA of the display device 1 of embodiment 1, and a non-light-emitting charge-transfer element 6R with a red light-emitting layer 8R, a non-light-emitting charge-transfer element 6G with a green light-emitting layer 8G, and a non-light-emitting charge-transfer element 6B with a blue light-emitting layer 8B provided in the non-display area NDA1.

As shown in FIG. 3, the red subpixel RSUB provided in the display area DA of the display device 1 includes a red light-emitting element 5R including a red light-emitting layer 8R, the green subpixel GSUB provided in the display area DA of the display device 1 includes a green light-emitting element 5G including a green light-emitting layer 8G, and the blue subpixel BSUB provided in the display area DA of the display device 1 includes a blue light-emitting element 5B including a blue light-emitting layer 8B. The red light-emitting element 5R includes a lower electrode 22 that is an anode, a hole injection layer 24, a hole transport layer 25, a red light-emitting layer 8R, an electron transport layer 26, an electron injection layer 27, and a first upper electrode layer 28 that is a cathode. The green light-emitting element 5G includes a lower electrode 22 that is an anode, a hole injection layer 24, a hole transport layer 25, a green light-emitting layer 8G, an electron transport layer 26, an electron injection layer 27, and a first upper electrode layer 28 that is a cathode. The blue light-emitting element 5B includes a lower electrode 22 that is an anode, a hole injection layer 24, a hole transport layer 25, a blue light-emitting layer 8B, an electron transport layer 26, an electron injection layer 27, and a first upper electrode layer 28 that is a cathode.

In addition, between the lower electrode 22 and red light-emitting layer 8R of the red light-emitting element 5R of the display device 1 shown in Figure 3, between the lower electrode 22 and green light-emitting layer 8G of the green light-emitting element 5G, and between the lower electrode 22 and blue light-emitting layer 8B of the blue light-emitting element 5B, a hole injection layer 24 and a hole transport layer 25 are provided as a charge transfer layer that is a single continuous layer provided across the display area DA and the non-display area NDA1, for example, as a charge transfer layer (hole transfer layer) that is a common layer formed over the entire surface of the display area DA and the non-display area NDA1. In this embodiment, an example is given in which both the hole injection layer 24 and the hole transport layer 25 are provided as a charge transfer layer (hole transfer layer) that is a common layer formed over the entire surface of the display area DA and the non-display area NDA1, but this is not limited to this, and only one of the hole injection layer 24 and the hole transport layer 25 may be provided as a charge transfer layer (hole transfer layer) that is a common layer formed over the entire surface of the display area DA and the non-display area NDA1.

In this embodiment, as shown in FIG. 3, the first dummy subpixel DRSUB provided in the non-display area NDA1 of the display device 1 is provided with a non-light-emitting charge transfer element 6R having a forward stack structure in which, from the substrate 2 side, a lower electrode 22 as an anode, a hole injection layer 24, a hole transport layer 25, a red light-emitting layer 8R, an electron transport layer 26, an electron injection layer 27, and a second upper electrode layer 28a as a cathode are stacked in this order on the substrate 2, and the second dummy subpixel DGSUB is provided with a non-light-emitting charge transfer element 6R having a forward stack structure in which, from the substrate 2 side, a lower electrode 22 as an anode, a hole injection layer 24, a hole transport layer 25, a green light-emitting layer 8R, an electron transport layer 26, an electron injection layer 27, and a second upper electrode layer 28a as a cathode are stacked in this order on the substrate 2. A non-light-emitting charge transfer element 6G is provided in which a color light-emitting layer 8G, an electron transport layer 26, an electron injection layer 27, and a second upper electrode layer 28a which is a cathode are stacked in this order, and the third dummy subpixel DBSUB is provided on the substrate 2 with a non-light-emitting charge transfer element 6B in a forward stack structure in which, from the substrate 2 side, a lower electrode 22 which is an anode, a hole injection layer 24, a hole transport layer 25, a blue light-emitting layer 8B, an electron transport layer 26, an electron injection layer 27, and a second upper electrode layer 28a which is a cathode are stacked in this order, but the present invention is not limited to this. For example, the non-display area NDA1 of the display device 1 may include only one or two of the first dummy subpixel DRSUB including a non-light-emitting charge transfer element 6R having a forward stack structure, the second dummy subpixel DGSUB including a non-light-emitting charge transfer element 6G having a forward stack structure, and the third dummy subpixel DBSUB including a non-light-emitting charge transfer element 6B having a forward stack structure. In addition, in the non-light-emitting

charge transfer elements

6R, 6G, and 6B having a forward stack structure, one of the hole injection layer 24 and the hole transport layer 25 may be omitted.

As described above, the charge transfer layer (hole transfer layer), which is a continuous layer provided across the display area DA and non-display area NDA1 of the display device 1, may be at least one of the hole injection layer 24 and the hole transport layer 25.

In addition, at least one of the electron transport layer 26 and the electron injection layer 27 may be provided between the light-emitting

layers

8R, 8G, and 8B in the display area DA of the display device 1 and the first upper electrode layer 28, and between the light-emitting

layers

8R, 8G, and 8B in the non-display area NDA1 of the display device 1 and the second upper electrode layer 28a, or both the electron transport layer 26 and the electron injection layer 27 may be omitted.

In this embodiment, the charge transfer layer (hole transfer layer) provided in the display area DA of the display device 1 and the charge transfer layer (hole transfer layer) provided in the non-display area NDA1 of the display device 1 are formed of the same material. That is, when the charge transfer layer (hole transfer layer) provided in the display area DA and the non-display area NDA1 is only the hole injection layer 24, the hole injection layer 24 provided in the display area DA and the hole injection layer 24 provided in the non-display area NDA1 are made of the same material, when the charge transfer layer (hole transfer layer) provided in the display area DA and the non-display area NDA1 is only the hole transport layer 25, the hole transport layer 25 provided in the display area DA and the hole transport layer 25 provided in the non-display area NDA1 are made of the same material, and when the charge transfer layer (hole transfer layer) provided in the display area DA and the non-display area NDA1 is the hole injection layer 24 and the hole transport layer 25, the hole injection layer 24 and the hole transport layer 25 provided in the display area DA and the hole injection layer 24 and the hole transport layer 25 provided in the non-display area NDA1 are each made of the same material.

Without being limited to this, the charge transfer layer (hole transfer layer) provided in the display area DA of the display device 1 and the charge transfer layer (hole transfer layer) provided in the non-display area NDA1 of the display device 1 may be formed of different materials as long as they are one continuous layer that allows holes to move from the display area DA to the non-display area NDA1.

In addition, in this embodiment, a case is described in which the red subpixel RSUB and the first dummy subpixel DRSUB are formed in the same shape, the green subpixel GSUB and the second dummy subpixel DGSUB are formed in the same shape, and the blue subpixel BSUB and the third dummy subpixel DBSUB are formed in the same shape, but this is not limiting. For example, the subpixels provided in the display area DA and the dummy subpixels provided in the non-display area NDA1 may have different shapes.

In the case of the red light-emitting element 5R, green light-emitting element 5G, and blue light-emitting element 5B shown in FIG. 3, the lower electrode 22 as the anode may be formed from an electrode material that reflects visible light, and the first upper electrode layer 28 as the cathode may be formed from an electrode material that transmits visible light, to form a top-emission type light-emitting element that emits light from the upper side, that is, the first upper electrode layer 28 side, or the lower electrode 22 as the anode may be formed from an electrode material that transmits visible light, and the first upper electrode layer 28 as the cathode may be formed from an electrode material that reflects visible light, to form a bottom-emission type light-emitting element that emits light from the lower side, that is, the substrate 2 side.

When the red light-emitting element 5R, the green light-emitting element 5G, and the blue light-emitting element 5B are top-emission type light-emitting elements, the lower electrode 22 serving as the anode provided in the non-light-emitting

charge transfer elements

6R, 6G, and 6B shown in FIG. 3 is formed of an electrode material that reflects visible light, and the second upper electrode layer 28a serving as the cathode is a resistance adjustment layer having a resistivity higher than that of the first upper electrode layer 28 and being 1×10 ⁹ Ω·cm or less, and may be formed of an electrode material that transmits visible light or an electrode material that reflects visible light.

On the other hand, when the red light-emitting element 5R, the green light-emitting element 5G, and the blue light-emitting element 5B are bottom-emission type light-emitting elements, the lower electrode 22 serving as the anode provided in the non-light-emitting

charge transfer elements

6R, 6G, and 6B shown in FIG. 3 is formed of an electrode material that transmits visible light, and the second upper electrode layer 28a serving as the cathode is a resistance adjustment layer having a resistivity higher than that of the first upper electrode layer 28 and not more than 1×10 ⁹ Ω cm, and may be formed of an electrode material that transmits visible light or an electrode material that reflects visible light.

The electrode material that reflects visible light is not particularly limited as long as it can reflect visible light and has electrical conductivity. For example, metal materials such as Al, Mg, Li, Ag, etc., alloys of the above metal materials, laminates of the above metal materials and transparent metal oxides (e.g., indium tin oxide, indium zinc oxide, indium gallium zinc oxide, etc.), or laminates of the above alloys and the above transparent metal oxides can be used.

On the other hand, the electrode material that transmits visible light is not particularly limited as long as it can transmit visible light and has electrical conductivity, but examples that can be used include transparent metal oxides (e.g., indium tin oxide, indium zinc oxide, indium gallium zinc oxide, etc.), and thin films made of metal materials such as Al, Mg, Li, and Ag.

In the display device 1 of this embodiment shown in Figure 3, in order to realize a display device equipped with top-emission type light-emitting elements, an electrode material that reflects visible light, in which Ag and a transparent metal oxide (e.g., indium tin oxide) are laminated in this order from the substrate 2 side, is used as the lower electrode 22 which is the anode, an Al thin film (resistivity ρ: 2.65 x 10 ^-8 Ω·cm) is used as the first upper electrode layer 28 which is the cathode, and a Ti film (resistivity ρ: 4.20 x 10 ^-7 Ω·cm) is used as the second upper electrode layer 28a which is the cathode, will be described as an example, but the present invention is not limited to this. For example, an Ag thin film (resistivity ρ: 1.59× ^10-8 Ω·cm) or an Mg thin film (resistivity ρ: 4.42× ^10-8 Ω·cm) may be used as the first upper electrode layer 28, which is the cathode, and a Cr film (resistivity ρ: 1.29× ^10-7 Ω·cm) or an Ni film (resistivity ρ: 6.99× ^10-8 Ω·cm) may be used as the second upper electrode layer 28a, which is the cathode.

The resistance adjustment layer described above only needs to have a resistivity higher than that of the first upper electrode layer 28 and equal to or less than 1×10 ⁹ Ω·cm, and may be formed of, for example, a semiconductive material (resistivity ρ: 1×10 ⁵ Ω·cm or more and 1×10 ⁹ Ω·cm or less). An example of the semiconductive material is, for example, a polymer material containing a conductive agent in an amount such that the resistivity is 1×10 ⁵ Ω·cm or more and 1×10 ⁹ Ω·cm or less, but is not limited thereto.

In the display device 1 of this embodiment shown in Figure 3, the non-light-emitting

charge transfer elements

6R, 6G, 6B have a charge transfer layer (hole transfer layer), for example, a resistance adjustment layer having a resistivity higher than that of the first upper electrode layer 28 and 1 x 10 9 Ω-cm or less between a first surface M1, which is the surface of the hole transport layer 25 facing the light-emitting

layers

8R, 8G, ^8B , and a second surface M2, which is the surface of the second upper electrode layer 28a opposite the substrate 2.As an example of this case, the first upper electrode layer 28 and the second upper electrode layer 28a are electrically connected, and the resistance adjustment layer having a resistivity higher than that of the first upper electrode layer 28 and 1 x 10 ⁹ Ω-cm or less is the second upper electrode layer 28a, but this is not limited to this. For example, as in a third embodiment (see FIG. 8 ) described later, the first upper electrode layer 28 and the second upper electrode layer 28a are a single continuous layer made of the same material, and a resistance adjustment layer 28c having a resistivity higher than that of the first upper electrode layer 28 and equal to or less than 1×10 9 Ω cm may be provided between a first surface M1, which is the surface of the hole transport layer 25 facing the light-emitting

layers

8R, 8G, and 8B, and a third surface M3, which is the surface of the second upper electrode layer 28a facing the light-emitting

layers

8R, ^8G , and 8B.

The material used for the hole injection layer 24 is not particularly limited as long as it is a hole injection material that can stabilize the injection of holes into the red light-emitting layer 8R, the green light-emitting layer 8G, and the blue light-emitting layer 8B. For example, PEDOT can be given as an example, but is not limited to this.

The material used for the hole transport layer 25 is not particularly limited as long as it is a hole transport material that can transport holes injected from the lower electrode 22, which is the anode, into the red light-emitting layer 8R, the green light-emitting layer 8G, and the blue light-emitting layer 8B. In particular, it is preferable for the hole transport material to have high hole mobility. For example, TFB (ADS) can be given as an example, but the material is not limited to this.

The material used for the electron transport layer 26 is not particularly limited as long as it is an electron transport material capable of transporting electrons injected from the first upper electrode layer 28 or the second upper electrode layer 28a, which is the cathode, into the red light-emitting layer 8R, the green light-emitting layer 8G, and the blue light-emitting layer 8B. In particular, it is preferable that the electron transport material has high electron mobility. For example, ZnMgO can be given as an example, but the present invention is not limited to this.

The material used for the electron injection layer 27 is not particularly limited as long as it is an electron injection material that can stabilize the injection of electrons into the red light-emitting layer 8R, the green light-emitting layer 8G, and the blue light-emitting layer 8B. For example, examples of the electron injection material include alkali metals or alkaline earth metals such as aluminum, strontium, calcium, lithium, cesium, magnesium oxide, aluminum oxide, strontium oxide, lithium oxide, lithium fluoride, magnesium fluoride, strontium fluoride, calcium fluoride, barium fluoride, cesium fluoride, polymethyl methacrylate polystyrene sodium sulfonate, oxides of alkali metals or alkaline earth metals, fluorides of alkali metals or alkaline earth metals, organic complexes of alkali metals, etc.

The sealing layer 29 provided on the first upper electrode layer 28 and the second upper electrode layer 28a is a light-transmitting film, and can be composed of, for example, an inorganic sealing film covering the first upper electrode layer 28 and the second upper electrode layer 28a, an organic film above the inorganic sealing film, and an inorganic sealing film above the organic film. The sealing layer 29 prevents the penetration of water, oxygen, etc. into the light-emitting elements of each color.

3, according to the display device 1, the holes H+ that have moved from the display area DA to the non-display area NDA1 through at least one of the charge transfer layer (hole transfer layer) hole injection layer 24 and the hole transport layer ²⁵ are accumulated in the non-display area NDA1 where they have nowhere to go. According to the non-light-emitting

charge transfer elements

6R, 6G, and 6B provided in the non-display area NDA1, as described above, the second upper electrode layer 28a is provided as a resistance adjustment layer having a resistivity higher than that of the first upper electrode layer 28 and being 1×10 ⁹ Ω·cm or less, and therefore, due to a decrease in the voltage applied between the lower electrode 22 and the second upper electrode layer 28a, the recombination of the holes H ⁺ and the electrons e is suppressed in the light-emitting

layers

8R, 8G, and 8B, and the holes H ⁺ are allowed to flow to the second upper electrode layer 28a, allowing the holes H ⁺ accumulated in the non-display area NDA1 to escape. That is, in the non-light-emitting

charge transfer elements

6R, 6G, and 6B, the voltage applied between the lower electrode 22 and the second upper electrode layer 28a is smaller than the energy required for recombination of the holes H ⁺ and the electrons e in the light-emitting

layers

8R, 8G, and 8B, so that light emission can be suppressed and the holes H ⁺ can flow to the second upper electrode layer 28a. In this way, the accumulated holes H ⁺ move toward the second upper electrode layer 28a, and it is possible to suppress the accumulation of the holes H ⁺ in the non-display area NDA1 and the occurrence of bright lines in the non-display area NDA1.

FIG. 4 is a circuit diagram of the display device 1 shown in FIG. 3 near the boundary between the display area DA and the non-display area NDA1.

FIG. 4 shows a schematic circuit configuration of a drive circuit for a blue subpixel BSUB including a blue light-emitting element 5B provided in the display area DA of the display device 1, and a drive circuit for a first dummy subpixel DRSUB including a non-light-emitting charge transfer element 6R provided in the non-display area NDA1 of the display device 1 adjacent to the blue light-emitting element 5B. The drive circuit for the blue subpixel BSUB including the blue light-emitting element 5B and the drive circuit for the first dummy subpixel DRSUB including the non-light-emitting charge transfer element 6R are provided on the substrate 2 shown in FIG. 3.

As shown in FIG. 4, the drive circuit of the first dummy subpixel DRSUB including the non-light-emitting charge transfer element 6R provided in the non-display area NDA1 of the display device 1 adjacent to the blue light-emitting element 5B includes one non-light-emitting charge transfer element 6R, two transistors TR1-TR2, and one holding capacitor C1. Although not shown, the drive circuit of the blue subpixel BSUB including the blue light-emitting element 5B provided in the display area DA of the display device 1 has the same configuration as the drive circuit of the first dummy subpixel DRSUB including the non-light-emitting charge transfer element 6R described above, except that it includes the blue light-emitting element 5B instead of the non-light-emitting charge transfer element 6R.

4, in the drive circuit of the first dummy subpixel DRSUB including the non-light-emitting charge transfer element 6R, the drain electrode of transistor TR1, which is the drive transistor, is electrically connected to the lower electrode 22 of the non-light-emitting charge transfer element 6R, the gate electrode of transistor TR1 is electrically connected to one electrode of the holding capacitor C1 and the drain electrode of transistor TR2, which is the selection transistor, and the source electrode of transistor TR1 is electrically connected to the other electrode of the holding capacitor C1 and an ELVDD wiring VL to which a high-level power supply voltage ELVDD is supplied from a power supply circuit (not shown). Note that the first upper electrode layer 28 of the blue light-emitting element 5B and the second upper electrode layer 28a, which is the above-mentioned resistance adjustment layer of the non-light-emitting

charge transfer elements

6R, 6G, and 6B, are electrically connected to an ELVSS wiring (not shown) to which a low-level power supply voltage ELVSS is supplied from the power supply circuit. In addition, the source electrode of transistor TR2, which is a selection transistor, is electrically connected to a data signal line DL to which a data signal output from a data side driving circuit (not shown) is supplied, the gate electrode of transistor TR2 is electrically connected to a scanning signal line SL to which a scanning signal output from a scanning side driving circuit (not shown) is supplied, and the drain electrode of transistor TR2 is electrically connected to the gate electrode of transistor TR1 and one electrode of holding capacitor C1.

In the display device 1 shown in Figures 3 and 4, in which the display area DA and non-display area NDA1 are provided with a hole injection layer 24 and a hole transport layer 25 as charge transfer layers (hole transfer layers), as described above, the non-light-emitting

charge transfer elements

6R, 6G, and 6B are provided in the non-display area NDA1 of the display device 1, so that it is possible to prevent bright lines from appearing around the edges of the display area DA that is provided near the non-display area NDA1 of the display device 1.

FIG. 5 is a cross-sectional view showing the schematic configuration of a display device 100, which is a comparative example in which red light-emitting elements 5R, green light-emitting elements 5G, and blue light-emitting elements 5B provided around the edge periphery DAER of the display area DA emit light brighter than intended, resulting in visible bright lines.

As shown in FIG. 5, the red subpixel RSUB provided in the display area DA including the edge periphery DAER of the display area DA of the display device 100 includes a red light-emitting element 5R including a red light-emitting layer 8R, the green subpixel GSUB provided in the display area DA including the edge periphery DAER of the display area DA of the display device 100 includes a green light-emitting element 5G including a green light-emitting layer 8G, and the blue subpixel BSUB provided in the display area DA including the edge periphery DAER of the display area DA of the display device 100 includes a blue light-emitting element 5B including a blue light-emitting layer 8B. The red light-emitting element 5R includes a lower electrode 22 that is an anode, a hole injection layer 24, a hole transport layer 25, a red light-emitting layer 8R, an electron transport layer 26, an electron injection layer 27, and a first upper electrode layer 28 that is a cathode. The green light-emitting element 5G includes a lower electrode 22 that is an anode, a hole injection layer 24, a hole transport layer 25, a green light-emitting layer 8G, an electron transport layer 26, an electron injection layer 27, and a first upper electrode layer 28 that is a cathode. The blue light-emitting element 5B includes a lower electrode 22 that is an anode, a hole injection layer 24, a hole transport layer 25, a blue light-emitting layer 8B, an electron transport layer 26, an electron injection layer 27, and a first upper electrode layer 28 that is a cathode.

The display device 100 shown in FIG. 5 is a comparative example. Between the lower electrode 22 and the red light-emitting layer 8R of the red light-emitting element 5R, between the lower electrode 22 and the green light-emitting layer 8G of the green light-emitting element 5G, and between the lower electrode 22 and the blue light-emitting layer 8B of the blue light-emitting element 5B, a hole injection layer 24 and a hole transport layer 25 are provided as a charge transfer layer (hole transfer layer) that is a common layer formed over the entire surface of the display area DA.

FIG. 6 is a circuit diagram for explaining why bright lines are visible around the edge DAER of the display area DA of the display device 100, which is a comparative example shown in FIG. 5. FIG. 6 shows a schematic circuit configuration of a drive circuit for a red sub-pixel RSUB including a red light-emitting element 5R provided around the edge DAER of the display area DA of the display device 100, which is a comparative example shown in FIG. 5, and a blue light-emitting element 5B arranged adjacent to the red light-emitting element 5R.

As shown in FIG. 6, the drive circuit of the red subpixel RSUB including the red light-emitting element 5R provided in the edge periphery DAER of the display area DA of the display device 100, which is a comparative example, includes one light-emitting element, two transistors TR1-TR2, and one storage capacitor C1. The transistor TR1 is a drive transistor, and the transistor TR2 is a selection transistor. Although not shown, the drive circuit of the green subpixel GSUB including the green light-emitting element 5G provided in the edge periphery DAER of the display area DA of the display device 100, which is a comparative example, and the drive circuit of the blue subpixel BSUB including the blue light-emitting element 5B provided in the edge periphery DAER of the display area DA of the display device 100, which is a comparative example, are also configured in the same way.

In the drive circuit of the red subpixel RSUB including the red light emitting element 5R shown in FIG. 6, the drain electrode of the transistor TR1, which is the drive transistor, is electrically connected to the lower electrode 22 of the red light emitting element 5R, the gate electrode of the transistor TR1 is electrically connected to one side electrode of the holding capacitor C1 and the drain electrode of the transistor TR2, which is the selection transistor, and the source electrode of the transistor TR1 is electrically connected to the other side electrode of the holding capacitor C1 and the ELVDD wiring VL to which the high-level power supply voltage ELVDD is supplied from a power supply circuit not shown. In addition, the source electrode of the transistor TR2, which is the selection transistor, is electrically connected to the data signal line DL to which the data signal output from the data side drive circuit not shown is supplied, the gate electrode of the transistor TR2 is electrically connected to the scanning signal line SL to which the scanning signal output from the scanning side drive circuit not shown is supplied, and the drain electrode of the transistor TR2 is electrically connected to the gate electrode of the transistor TR1 and one side electrode of the holding capacitor C1.

In the display device 100 shown in Fig. 5, which is a comparative example in which a hole injection layer 24 and a hole transport layer 25 are provided as a charge transfer layer (hole transfer layer) that is a common layer formed on the entire surface of the display area DA, a bright line is seen in the edge periphery DAER of the display area DA. The inventors of the present disclosure believe that one of the causes of this is that, as shown in Figs. 5 and 6, holes H ⁺ that have moved to the edge periphery DAER of the display area DA through the hole injection layer 24 and the hole transport layer 25 that are charge transfer layers (hole transfer layers) accumulate in the edge periphery DAER of the display area DA where there is nowhere to go, and in the light-emitting element provided in the edge periphery DAER of the display area DA, the accumulated holes H ⁺ move toward the first upper electrode layer 28, resulting in light emission that is brighter than the intended brightness. In the comparative example, the display device 100 has been described as an example in which a hole injection layer 24 and a hole transport layer 25 are provided as a charge transfer layer (hole transfer layer), which is a common layer formed over the entire surface of the display area DA. However, this is not limited to this example, and even if only one of the hole injection layer 24 and the hole transport layer 25 is provided, a bright line will similarly be visible around the edge DAER of the display area DA.

[Embodiment 2]
Next, a second embodiment of the present disclosure will be described with reference to FIG. 7. The display device 1a of this embodiment is different from the first embodiment described above in that the first upper electrode layer 28 is also provided in the non-display area NDA1 as one continuous layer, and in the non-display area NDA1, the second upper electrode layer 28a and the first upper electrode layer 28 are stacked in this order from the substrate 2 side. The rest is as described in the first embodiment. For convenience of explanation, the same reference numerals are used for members having the same functions as the members shown in the drawings of the first embodiment, and their explanations are omitted.

FIG. 7 is a cross-sectional view showing a schematic configuration of a red light-emitting element 5R, a green light-emitting element 5G, and a blue light-emitting element 5B provided in the display area DA of the display device 1a of embodiment 2, and a non-light-emitting charge-transfer element 6Ra with a red light-emitting layer 8R, a non-light-emitting charge-transfer element 6Ga with a green light-emitting layer 8G, and a non-light-emitting charge-transfer element 6Ba with a blue light-emitting layer 8B provided in the non-display area NDA1.

As shown in FIG. 7, in each of the non-light-emitting charge transfer element 6Ra with a red light-emitting layer 8R, the non-light-emitting charge transfer element 6Ga with a green light-emitting layer 8G, and the non-light-emitting charge transfer element 6Ba with a blue light-emitting layer 8B provided in the non-display area NDA1 of the display device 1a, the first upper electrode layer 28 is also provided in the non-display area NDA1 as one continuous layer, and in the non-display area NDA1, the second upper electrode layer 28a and the first upper electrode layer 28 are stacked in this order from the substrate 2 side to form the laminate 28b. In such a case, the laminate 28b becomes the cathode.

According to the non-light-emitting charge transfer elements 6Ra, 6Ga, and 6Ba provided in the non-display area NDA1, the second upper electrode layer 28a is provided as a resistance adjustment layer having a resistivity higher than that of the first upper electrode layer 28 and being 1×10 ⁹ Ω·cm or less, so that the voltage applied between the lower electrode 22 and the laminate 28b serving as the cathode is reduced, and the recombination of the holes H ⁺ and the electrons e is suppressed in the light-emitting

layers

8R, 8G, and 8B, and the holes H ⁺ are allowed to flow to the laminate 28b serving as the cathode, and the holes H ⁺ accumulated in the non-display area NDA1 can be released. The holes H ⁺ thus accumulated move toward the laminate 28b serving as the cathode, and the accumulation of the holes H ⁺ in the non-display area NDA1 and the occurrence of bright lines in the non-display area NDA1 can be suppressed.

[Embodiment 3]
Next, the third embodiment of the present disclosure will be described based on FIG. 8. In the display device 1b of this embodiment, the first upper electrode layer 28 and the second upper electrode layer 28a are one continuous layer formed of the same material, and the resistance adjustment layer 28c, which has a resistivity higher than that of the first upper electrode layer 28 and is 1×10 ⁹ Ω·cm or less, is provided between the first surface M1, which is the surface of the hole transport layer 25, which is the charge transfer layer (hole transfer layer), on the

light emitting layers

8R, 8G, and 8B side, and the third surface M3, which is the surface of the second upper electrode layer 28a on the

light emitting layers

8R, 8G, and 8B side. The rest is as described in the first and second embodiments. For convenience of explanation, the same reference numerals are used for members having the same functions as the members shown in the drawings of the first and second embodiments, and their explanations are omitted.

FIG. 8 is a cross-sectional view showing a schematic configuration of a red light-emitting element 5R, a green light-emitting element 5G, and a blue light-emitting element 5B provided in the display area DA of the display device 1b of embodiment 3, and a non-light-emitting charge-transfer element 6Rb with a red light-emitting layer 8R, a non-light-emitting charge-transfer element 6Gb with a green light-emitting layer 8G, and a non-light-emitting charge-transfer element 6Bb with a blue light-emitting layer 8B provided in the non-display area NDA1.

As shown in FIG. 8, in each of the non-light-emitting charge transfer element 6Rb having a red light-emitting layer 8R, the non-light-emitting charge transfer element 6Gb having a green light-emitting layer 8G, and the non-light-emitting charge transfer element 6Bb having a blue light-emitting layer 8B provided in the non-display area NDA1 of the display device 1b, the first upper electrode layer 28 and the second upper electrode layer 28a are one continuous layer formed of the same material, and a resistance adjustment layer 28c having a resistivity higher than that of the first upper electrode layer 28 and being 1×10 ⁹ Ω·cm or less is provided between a first surface M1 which is the surface of the hole transport layer 25, which is a charge transfer layer (hole transfer layer), facing the light-emitting

layers

8R, 8G, and 8B, and a third surface M3 which is the surface of the second upper electrode layer 28a facing the light-emitting

layers

8R, 8G, and 8B.

In this embodiment, the case where the resistance adjustment layer 28c is provided between the electron transport layer 26 and the electron injection layer 27 will be described as an example, but the present invention is not limited to this. For example, the resistance adjustment layer 28c may be provided between the second upper electrode layer 28a and the electron injection layer 27, between the electron transport layer 26 and the light-emitting

layers

8R, 8G, and 8B, or between the light-emitting

layers

8R, 8G, and 8B and the hole transport layer 25, or may be provided at multiple positions among the above positions.

In the non-light-emitting charge transfer elements 6Rb, 6Gb, and 6Bb provided in the non-display area NDA1, the resistance adjustment layer 28c is provided between the first surface M1, which is the surface of the hole transport layer 25, which is a charge transfer layer (hole transfer layer), facing the light-emitting

layers

8R, 8G, and 8B, and the third surface M3, which is the surface of the second upper electrode layer 28a facing the light-emitting

layers

8R, 8G, and 8B. Due to a decrease in the voltage applied between the lower electrode 22 and the second upper electrode layer 28a, which is the cathode, recombination of holes H ⁺ and electrons e is suppressed in the light-emitting

layers

8R, 8G, and 8B, and the holes H ⁺ are caused to flow to the second upper electrode layer 28a, which is the cathode, thereby allowing the holes H ⁺ accumulated in the non-display area NDA1 to escape. The accumulated holes H ⁺ move in the direction of the second upper electrode layer 28a, which is the cathode, and it is possible to suppress the accumulation of holes H ⁺ in the non-display area NDA1 and the occurrence of bright lines in the non-display area NDA1.

[Embodiment 4]
Next, a fourth embodiment of the present disclosure will be described with reference to FIG. 9. In the display device 1c of this embodiment, the first upper electrode layer 28 and the second upper electrode layer 28a are electrically separated, and the second upper electrode layer 28a is a resistance adjustment layer having a resistivity higher than that of the first

upper electrode layer

28, 1×10 ⁹ Ω·cm or less, and a first voltage is applied to the first upper electrode layer 28 through a first wiring, and a second voltage is applied to the second upper electrode layer 28a through a second wiring, and the first voltage and the second voltage are the same voltage. This is different from the first to third embodiments described above. The rest is as described in the first to third embodiments. For convenience of explanation, the same reference numerals are used for members having the same functions as the members shown in the drawings of the first to third embodiments, and their explanations are omitted.

FIG. 9 is a cross-sectional view showing a schematic configuration of a red light-emitting element 5R, a green light-emitting element 5G, and a blue light-emitting element 5B provided in the display area DA of the display device 1c of embodiment 4, and a non-light-emitting charge-transfer element 6R with a red light-emitting layer 8R, a non-light-emitting charge-transfer element 6G with a green light-emitting layer 8G, and a non-light-emitting charge-transfer element 6B with a blue light-emitting layer 8B provided in the non-display area NDA1.

As shown in FIG. 9, in the display device 1c, a groove HOL for electrically isolating the first upper electrode layer 28 and the second upper electrode layer 28a is provided in an area including the end DAE of the display area DA, and the first upper electrode layer 28 and the second upper electrode layer 28a are electrically isolated.

In this embodiment, a case where the groove HOL is also provided in the electron transport layer 26 and the electron injection layer 27 will be described as an example, but this is not limited thereto, and the groove HOL may be provided only between the first upper electrode layer 28 and the second upper electrode layer 28a.

As shown in FIG. 9, in display device 1c, the first upper electrode layer 28 and the second upper electrode layer 28a are electrically separated, and the second upper electrode layer 28a is a resistance adjustment layer having a resistivity higher than that of the first upper electrode layer 28, being 1×10 ⁹ Ω·cm or less. A first voltage is applied to the first upper electrode layer 28 via a first wiring, and a second voltage is applied to the second upper electrode layer 28a via a second wiring, and the first voltage and the second voltage are the same voltage.

The display device 1c can prevent the red light-emitting element 5R, green light-emitting element 5G, and blue light-emitting element 5B provided in the display area DA from being affected by the non-light-emitting

charge transfer elements

6R, 6G, and 6B provided in the non-display area NDA1.

[Embodiment 5]
Next, a fifth embodiment of the present disclosure will be described with reference to Figs. 10 to 13. The display device 1d of this embodiment is different from the first to fourth embodiments in that the display area DA includes red light emitting element 5R', green light emitting element 5G', and blue light emitting element 5B', which are light emitting elements with an inverted stack structure, and the non-display area NDA1 includes non-light emitting charge transfer elements 6R', 6G', and 6B', which are non-light emitting charge transfer elements with an inverted stack structure. The rest is as described in the first to fourth embodiments. For convenience of explanation, the same reference numerals are used for members having the same functions as the members shown in the drawings of the first to fourth embodiments, and their explanations are omitted.

FIG. 10 is a cross-sectional view showing the schematic configuration of red light-emitting element 5R', green light-emitting element 5G', and blue light-emitting element 5B', which are light-emitting elements with an inverted stack structure provided in display area DA of display device 1d of embodiment 5, and non-light-emitting charge-transfer elements 6R', 6G', and 6B', which are non-light-emitting charge-transfer elements with an inverted stack structure provided in non-display area NDA1.

In this embodiment, as shown in FIG. 10, the red subpixel RSUB provided in the display area DA of the display device 1d is provided with a red light-emitting element 5R' having an inverted stack structure in which, from the substrate 2' side, a lower electrode 22' serving as a cathode, an electron injection layer 27, an electron transport layer 26, a red light-emitting layer 8R, a hole transport layer 25, a hole injection layer 24, and a first upper electrode layer 28' serving as an anode are stacked in this order on the substrate 2'. The green subpixel GSUB is provided with a lower electrode 22' serving as a cathode, an electron injection layer 27, an electron transport layer 26, a green light-emitting layer 8R, a hole transport layer 25, a hole injection layer 24, and a first upper electrode layer 28' serving as an anode on the substrate 2'. A green light emitting element 5G' is provided with an inverted stack structure in which a light emitting layer 8G, a hole transport layer 25, a hole injection layer 24, and a first upper electrode layer 28' that is an anode are stacked in this order, and the blue subpixel BSUB is provided with a blue light emitting element 5B' with an inverted stack structure in which a lower electrode 22' that is a cathode, an electron injection layer 27, an electron transport layer 26, a blue light emitting layer 8B, a hole transport layer 25, a hole injection layer 24, and a first upper electrode layer 28' that is an anode are stacked in this order from the substrate 2' side on the substrate 2', but the present invention is not limited to this.

In addition, in this embodiment, as shown in FIG. 10, the first dummy subpixel DRSUB provided in the non-display area NDA1 of the display device 1d is provided with a non-light-emitting charge transfer element 6R' having an inverted stack structure in which, from the substrate 2' side, a lower electrode 22' which is a cathode, an electron injection layer 27, an electron transport layer 26, a hole transport layer 25, a hole injection layer 24, and a second upper electrode layer 28a' which is an anode are stacked in this order on the substrate 2'. The second dummy subpixel DGSUB is provided with a non-light-emitting charge transfer element 6R' having an inverted stack structure in which, from the substrate 2' side, a lower electrode 22' which is a cathode, an electron injection layer 27, an electron transport layer 26, a hole transport layer 25, a hole injection layer 24, and a second upper electrode layer 28a' which is an anode are stacked in this order on the substrate 2'. The third dummy subpixel DBSUB is provided with a non-light-emitting charge transfer element 6G' having an inverted stack structure in which a lower electrode 22' serving as a cathode, an electron injection layer 27, an electron transport layer 26, a hole transport layer 25, a hole injection layer 24, and a second upper electrode layer 28a' serving as an anode are stacked in this order on the substrate 2'. An example will be described in which a non-light-emitting charge transfer element 6B' having an inverted stack structure in which a lower electrode 22' serving as a cathode, an electron injection layer 27, an electron transport layer 26, a hole transport layer 25, a hole injection layer 24, and a second upper electrode layer 28a' serving as an anode are stacked in this order on the substrate 2', but the present invention is not limited to this.

The charge transfer layer (electron transfer layer), which is a continuous layer provided across the display area DA and non-display area NDA1 of the display device 1d, may be at least one of the electron injection layer 27 and the electron transport layer 26.

In addition, at least one of the hole transport layer 25 and the hole injection layer 24 may be provided between the light emitting

layers

8R, 8G, 8B and the first upper electrode layer 28' in the display area DA of the display device 1d, and between the light emitting

layers

8R, 8G, 8B and the second upper electrode layer 28a' in the non-display area NDA1 of the display device 1d, or both the hole transport layer 25 and the hole injection layer 24 may be omitted.

In this embodiment, the charge transfer layer (electron transfer layer) provided in the display area DA of the display device 1d and the charge transfer layer (electron transfer layer) provided in the non-display area NDA1 of the display device 1d are formed of the same material. That is, when the charge transfer layer (electron transfer layer) provided in the display area DA and the non-display area NDA1 is only the electron injection layer 27, the electron injection layer 27 provided in the display area DA and the electron injection layer 27 provided in the non-display area NDA1 are made of the same material, when the charge transfer layer (electron transfer layer) provided in the display area DA and the non-display area NDA1 is only the electron transport layer 26, the electron transport layer 26 provided in the display area DA and the electron transport layer 26 provided in the non-display area NDA1 are made of the same material, and when the charge transfer layer (electron transfer layer) provided in the display area DA and the non-display area NDA1 is the electron injection layer 27 and the electron transport layer 26, the electron injection layer 27 and the electron transport layer 26 provided in the display area DA and the electron injection layer 27 and the electron transport layer 26 provided in the non-display area NDA1 are each made of the same material.

Without being limited to this, the charge transfer layer (electron transfer layer) provided in the display area DA of the display device 1d and the charge transfer layer (electron transfer layer) provided in the non-display area NDA1 of the display device 1d may be formed of different materials as long as they are one continuous layer that allows the movement of electrons from the display area DA to the non-display area NDA1.

When the red light-emitting element 5R', green light-emitting element 5G', and blue light-emitting element 5B' shown in Figure 10 are top-emission type light-emitting elements, the lower electrode 22' which is the cathode provided in the non-light-emitting charge transfer elements 6R', 6G', and 6B' shown in Figure 10 is formed of an electrode material that reflects visible light, and the second upper electrode layer 28a' which is the anode may be formed of an electrode material that transmits visible light or an electrode material that reflects visible light, as long as it is a resistance adjustment layer whose resistivity is higher than that of the first upper electrode layer 28' and is 1 x 10 ⁹ Ω cm or less.

On the other hand, when the red light-emitting element 5R', the green light-emitting element 5G' and the blue light-emitting element 5B' are bottom-emission type light-emitting elements, the lower electrode 22' serving as the cathode provided in the non-light-emitting charge transfer elements 6R', 6G', 6B' shown in FIG. 10 is formed of an electrode material that transmits visible light, and the second upper electrode layer 28a' serving as the anode is a resistance adjustment layer having a resistivity higher than that of the first upper electrode layer 28' and not more than 1×10 ⁹ Ω·cm, and may be formed of an electrode material that transmits visible light or an electrode material that reflects visible light.

In the display device 1d of this embodiment shown in FIG. 10, in order to realize a display device equipped with top-emission type light-emitting elements, an Al film is used as the lower electrode 22' which is the cathode, an ITO (indium tin oxide) film which is a transparent metal oxide is used as the first upper electrode layer 28' which is the anode, and an IZO (indium zinc oxide) film which is a transparent metal oxide having a higher resistivity than an ITO (indium tin oxide) film is used as the second upper electrode layer 28a' which is the anode. However, the present invention is not limited to this example.

In the display device 1d of this embodiment shown in Figure 10, the non-light-emitting charge transfer elements 6R', 6G', 6B' have a charge transfer layer (electron transfer layer), for example, a resistance adjustment layer having a resistivity higher than that of the first upper electrode layer 28' and 1 x 10 9 Ω-cm or less between a first surface M1 which is the surface of the electron transport layer 26 facing the light-emitting

layers

8R, ^8G , 8B, and a second surface M2 which is the surface of the second upper electrode layer 28a' opposite the substrate 2'.As an example of a case in which the first upper electrode layer 28' and the second upper electrode layer 28a' are electrically connected, and the resistance adjustment layer having a resistivity higher than that of the first upper electrode layer 28' and 1 x 10 ⁹ Ω-cm or less is the second upper electrode layer 28a', this will be described as a case in which, however, the present invention is not limited to this. For example, as in the seventh embodiment (see FIG. 15 ) described later, the non-light-emitting charge transfer element may include a charge transfer layer (electron transfer layer), for example, a resistance adjustment layer 28c' having a resistivity higher than that of the first upper electrode layer 28' and equal to or less than 1×10 9 Ω cm, between a first surface M1 which is the surface of the electron transport layer 26 facing the light-emitting

layers

8R, 8G, and 8B, and a third surface M3 which is the surface of the second upper electrode layer 28a' facing the light-emitting

layers

8R, ^8G , and 8B.

10, in the display device 1d, the electrons e that have moved from the display area DA to the non-display area NDA1 through at least one of the electron injection layer 27 and the electron transport layer 26, which are charge transfer layers (electron transfer layers), accumulate in the non-display area NDA1 where they have nowhere to go. As described above, in the non-light-emitting charge transfer elements 6R', 6G', and 6B' provided in the non-display area NDA1, the second upper electrode layer 28a' is provided as a resistance adjustment layer, and thus, in the light-emitting

layers

8R, 8G, and 8B, the recombination of the holes H ⁺ and the electrons e is suppressed due to the reduction in the voltage applied between the lower electrode 22' and the second upper electrode layer 28a', and the electrons e that have accumulated in the non-display area NDA1 can be made to flow to the second upper electrode layer 28a'. That is, in the non-light-emitting charge transfer elements 6R', 6G', and 6B', the voltage applied between the lower electrode 22' and the second upper electrode layer 28a' is smaller than the energy required for recombination of the holes H ⁺ and the electrons e in the light-emitting

layers

8R, 8G, and 8B, so that light emission can be suppressed and the electrons e can flow to the second upper electrode layer 28a'. In this way, the accumulated electrons e move toward the second upper electrode layer 28a', and it is possible to suppress the accumulation of the electrons e in the non-display area NDA1 and the occurrence of bright lines in the non-display area NDA1.

FIG. 11 is a circuit diagram of the display device 1d shown in FIG. 10 near the boundary between the display area DA and the non-display area NDA1.

FIG. 11 shows a schematic circuit configuration of a drive circuit for a blue subpixel BSUB including a blue light-emitting element 5B' provided in the display area DA of the display device 1d, and a drive circuit for a first dummy subpixel DRSUB including a non-emissive charge transfer element 6R' provided in the non-display area NDA1 of the display device 1d adjacent to the blue light-emitting element 5B'. The drive circuit for the blue subpixel BSUB including the blue light-emitting element 5B' and the drive circuit for the first dummy subpixel DRSUB including the non-emissive charge transfer element 6R' are provided on the substrate 2' shown in FIG. 10. The circuit configurations of the drive circuit for the blue subpixel BSUB including the blue light-emitting element 5B' and the drive circuit for the first dummy subpixel DRSUB including the non-emissive charge transfer element 6R' have been described above in embodiment 1, so a description thereof will be omitted here.

In the display device 1d shown in Figures 10 and 11, in which the display area DA and non-display area NDA1 are provided with an electron injection layer 27 and an electron transport layer 26 as charge transfer layers (electron transfer layers), as described above, non-light-emitting charge transfer elements 6R', 6G', and 6B' are provided in the non-display area NDA1 of the display device 1d, so that it is possible to prevent bright lines from appearing around the edges of the display area DA that is provided near the non-display area NDA1 of the display device 1d.

FIG. 12 is a cross-sectional view showing the schematic configuration of a display device 101, which is a comparative example in which red light-emitting elements 5R', green light-emitting elements 5G', and blue light-emitting elements 5B' provided around the edge periphery DAER of the display area DA emit light brighter than intended, resulting in visible bright lines.

As shown in FIG. 12, the red subpixel RSUB provided in the display area DA including the edge periphery DAER of the display area DA of the display device 101 includes a red light emitting element 5R' including a red light emitting layer 8R, the green subpixel GSUB provided in the display area DA including the edge periphery DAER of the display area DA of the display device 101 includes a green light emitting element 5G' including a green light emitting layer 8G, and the blue subpixel BSUB provided in the display area DA including the edge periphery DAER of the display area DA of the display device 101 includes a blue light emitting element 5B' including a blue light emitting layer 8B.

In the display device 101 shown in FIG. 12, which is a comparative example, an electron injection layer 27 and an electron transport layer 26 are provided as a charge transfer layer (electron transfer layer) that is a common layer formed over the entire display area DA between the lower electrode 22' and red light-emitting layer 8R of the red light-emitting element 5R', between the lower electrode 22' and green light-emitting layer 8G of the green light-emitting element 5G', and between the lower electrode 22' and blue light-emitting layer 8B of the blue light-emitting element 5B'.

FIG. 13 is a circuit diagram for explaining why bright lines are visible around the edge DAER of the display area DA of the display device 101, which is a comparative example shown in FIG. 12. FIG. 13 shows a schematic circuit configuration of a drive circuit for a red sub-pixel RSUB including a red light-emitting element 5R' provided around the edge DAER of the display area DA of the display device 101, which is a comparative example shown in FIG. 12, and a blue light-emitting element 5B' arranged adjacent to the red light-emitting element 5R'. Note that the circuit configuration shown in FIG. 13 has been described above in embodiment 1, so a description thereof will be omitted here.

In the display device 101 shown in FIG. 12, which is a comparative example in which an electron injection layer 27 and an electron transport layer 26 are provided as a charge transfer layer (electron transfer layer) that is a common layer formed over the entire surface of the display area DA, bright lines are visible in the periphery DAER of the edge of the display area DA. The inventors of the present disclosure believe that one of the causes of this is that, as shown in FIG. 12 and FIG. 13, electrons e that have moved to the periphery DAER of the edge of the display area DA via the electron injection layer 27 and electron transport layer 26, which are charge transfer layers (electron transfer layers), accumulate in the periphery DAER of the edge of the display area DA where they have nowhere to go, and in the light-emitting element provided in the periphery DAER of the edge of the display area DA, the accumulated electrons e move toward the first upper electrode layer 28', resulting in light emission that is brighter than the intended brightness. In the comparative display device 101, an example was given in which an electron injection layer 27 and an electron transport layer 26 are provided as a charge transport layer (electron transport layer) that is a common layer formed over the entire surface of the display area DA, but this is not limited to this, and even if only one of the electron injection layer 27 and the electron transport layer 26 is provided, a bright line will be visible around the edge DAER of the display area DA.

[Embodiment 6]
Next, the sixth embodiment of the present disclosure will be described with reference to FIG. 14. The display device 1e of this embodiment is different from the fifth embodiment in that the first upper electrode layer 28' is also provided in the non-display area NDA1 as one continuous layer, and the second upper electrode layer 28a' and the first upper electrode layer 28' are stacked in this order from the substrate 2' side in the non-display area NDA1. The rest is as described in the fifth embodiment. For convenience of explanation, the same reference numerals are used for the members having the same functions as those shown in the drawings of the fifth embodiment, and the explanation thereof will be omitted.

FIG. 14 is a cross-sectional view showing a schematic configuration of a red light-emitting element 5R', a green light-emitting element 5G', and a blue light-emitting element 5B' provided in the display area DA of the display device 1e of embodiment 6, and a non-light-emitting charge-transfer element 6Ra' with a red light-emitting layer 8R, a non-light-emitting charge-transfer element 6Ga' with a green light-emitting layer 8G, and a non-light-emitting charge-transfer element 6Ba' with a blue light-emitting layer 8B provided in the non-display area NDA1.

As shown in FIG. 14, in each of the non-light-emitting charge transfer element 6Ra' with a red light-emitting layer 8R, the non-light-emitting charge transfer element 6Ga' with a green light-emitting layer 8G, and the non-light-emitting charge transfer element 6Ba' with a blue light-emitting layer 8B provided in the non-display area NDA1 of the display device 1e, the first upper electrode layer 28' is also provided in the non-display area NDA1 as one continuous layer, and in the non-display area NDA1, the second upper electrode layer 28a' and the first upper electrode layer 28' are stacked in this order from the substrate 2' side to form the laminate 28b'. In such a case, the laminate 28b' serves as the anode.

According to the non-light-emitting charge transfer elements 6Ra', 6Ga', and 6Ba' provided in the non-display area NDA1, the second upper electrode layer 28a' is provided as a resistance adjustment layer having a resistivity higher than that of the first upper electrode layer 28' and a resistivity of 1×10 ⁹ Ω·cm or less, so that the recombination of the holes H ⁺ and the electrons e is suppressed in the light-emitting

layers

8R, 8G, and 8B due to a decrease in the voltage applied between the lower electrode 22' and the anode stack 28b', and the electrons e can flow to the anode stack 28b' and the electrons e accumulated in the non-display area NDA1 can be released. In this way, the accumulated electrons e move toward the anode stack 28b', and the accumulation of the electrons e in the non-display area NDA1 and the occurrence of bright lines in the non-display area NDA1 can be suppressed.

[Embodiment 7]
Next, the seventh embodiment of the present disclosure will be described based on FIG. 15. In the display device 1f of this embodiment, the first upper electrode layer 28' and the second upper electrode layer 28a' are one continuous layer formed of the same material, and the resistance adjustment layer 28c', which has a resistivity higher than that of the first upper electrode layer 28' and is 1×10 ⁹ Ω·cm or less, is provided between the first surface M1, which is the surface of the electron transport layer 26, which is the charge transfer layer (electron transfer layer), on the light-emitting

layers

8R, 8G, and 8B side, and the third surface M3, which is the surface of the second upper electrode layer 28a' on the light-emitting

layers

8R, 8G, and 8B side. The rest is as described in the fifth and sixth embodiments. For convenience of explanation, the same reference numerals are used for members having the same functions as the members shown in the drawings of the fifth and sixth embodiments, and their explanations are omitted.

FIG. 15 is a cross-sectional view showing a schematic configuration of a red light-emitting element 5R', a green light-emitting element 5G', and a blue light-emitting element 5B' provided in the display area DA of the display device 1f of embodiment 7, and a non-light-emitting charge-transfer element 6Rb' with a red light-emitting layer 8R, a non-light-emitting charge-transfer element 6Gb' with a green light-emitting layer 8G, and a non-light-emitting charge-transfer element 6Bb' with a blue light-emitting layer 8B provided in the non-display area NDA1.

As shown in FIG. 15, in each of the non-light-emitting charge transfer element 6Rb' having a red light-emitting layer 8R, the non-light-emitting charge transfer element 6Gb' having a green light-emitting layer 8G, and the non-light-emitting charge transfer element 6Bb' having a blue light-emitting layer 8B provided in the non-display area NDA1 of the display device 1f, the first upper electrode layer 28' and the second upper electrode layer 28a' are one continuous layer formed of the same material, and a resistance adjustment layer 28c' having a resistivity higher than that of the first upper electrode layer 28' and being 1×10 ⁹ Ω·cm or less is provided between a first surface M1 which is the surface of the electron transport layer 26, which is a charge transfer layer (electron transfer layer), facing the light-emitting

layers

8R, 8G, and 8B.

In this embodiment, the case where the resistance adjustment layer 28c' is provided between the hole transport layer 25 and the hole injection layer 24 will be described as an example, but the present invention is not limited to this. For example, the resistance adjustment layer 28c' may be provided between the second upper electrode layer 28a' and the hole injection layer 24, between the hole transport layer 25 and the light-emitting

layers

8R, 8G, and 8B, or between the light-emitting

layers

8R, 8G, and 8B and the electron transport layer 26, or may be provided at multiple positions among the above positions.

According to the non-light-emitting charge transfer elements 6Rb', 6Gb', and 6Bb' provided in the non-display area NDA1, the resistance adjustment layer 28c' is provided between the first surface M1, which is the surface of the electron transport layer 26, which is the charge transfer layer (electron transfer layer), on the light-emitting

layers

8R, 8G, and 8B side, so that the voltage applied between the lower electrode 22' and the second upper electrode layer 28a', which is the anode, is reduced, and the recombination of the holes H ⁺ and the electrons e is suppressed in the light-emitting

layers

8R, 8G, and 8B, and the electrons e are caused to flow to the second upper electrode layer 28a', which is the anode, and the electrons e accumulated in the non-display area NDA1 can be released. In this way, the accumulated electrons e move toward the second upper electrode layer 28a', which is the anode, and it is possible to suppress the accumulation of electrons e in the non-display area NDA1 and the occurrence of bright lines in the non-display area NDA1.

[Embodiment 8]
Next, an eighth embodiment of the present disclosure will be described based on FIG. 16. In the display device 1g of this embodiment, the first upper electrode layer 28' and the second upper electrode layer 28a' are electrically separated, and the second upper electrode layer 28a' is a resistance adjustment layer having a resistivity higher than that of the first upper electrode layer 28', 1×10 ⁹ Ω·cm or less, and a first voltage is applied to the first upper electrode layer 28' through a first wiring, and a second voltage is applied to the second upper electrode layer 28a' through a second wiring, and the first voltage and the second voltage are the same voltage. This embodiment differs from the fifth to seventh embodiments described above. The rest is as described in the fifth to seventh embodiments. For convenience of explanation, the same reference numerals are used for members having the same functions as the members shown in the drawings of the fifth to seventh embodiments, and their explanations are omitted.

FIG. 16 is a cross-sectional view showing a schematic configuration of a red light-emitting element 5R', a green light-emitting element 5G', and a blue light-emitting element 5B' provided in the display area DA of the display device 1g of embodiment 8, and a non-light-emitting charge-transfer element 6R' with a red light-emitting layer 8R, a non-light-emitting charge-transfer element 6G' with a green light-emitting layer 8G, and a non-light-emitting charge-transfer element 6B' with a blue light-emitting layer 8B provided in the non-display area NDA1.

As shown in FIG. 16, in the display device 1g, a groove HOL' for electrically isolating the first upper electrode layer 28' and the second upper electrode layer 28a' is provided in an area including the end DAE of the display area DA, and the first upper electrode layer 28' and the second upper electrode layer 28a' are electrically isolated.

In this embodiment, an example will be described in which the groove HOL' is also provided in the hole transport layer 25 and the hole injection layer 24, but this is not limiting, and the groove HOL' may be provided only between the first upper electrode layer 28' and the second upper electrode layer 28a'.

As shown in FIG. 16, in a display device 1g, a first upper electrode layer 28' and a second upper electrode layer 28a' are electrically separated, and a second upper electrode layer 28a' is a resistance adjustment layer having a resistivity higher than that of the first upper electrode layer 28' and being 1×10 ⁹ Ω·cm or less, a first voltage is applied to the first upper electrode layer 28' via a first wiring, and a second voltage is applied to the second upper electrode layer 28a' via a second wiring, and the first voltage and the second voltage are the same voltage.

The display device 1g can prevent the red light-emitting element 5R', green light-emitting element 5G', and blue light-emitting element 5B' provided in the display area DA from being affected by the non-light-emitting charge transfer elements 6R', 6G', and 6B' provided in the non-display area NDA1.

[Embodiment 9]
Next, a ninth embodiment of the present disclosure will be described with reference to FIG. 17. The display device 1h of this embodiment is different from the above-described first to eighth embodiments in that an imaging region TH that transmits imaging light is further provided inside the display region DA, and includes a non-display region (first non-display region) NDA1 provided to surround the outer periphery of the display region DA and a non-display region (second non-display region) NDA2 provided to surround the imaging region TH. The rest is as described in the first and second embodiments. For convenience of explanation, the same reference numerals are used for members having the same functions as those shown in the drawings of the first and second embodiments, and their explanations are omitted.

FIG. 17 is a plan view showing the schematic configuration of a display device 1h according to embodiment 9.

As shown in FIG. 17, the display device 1h further includes an imaging area TH that transmits imaging light, located inside the display area DA, and includes a non-display area (first non-display area) NDA1 that is provided so as to surround the outer periphery of the display area DA, and a non-display area (second non-display area) NDA2 that is provided so as to surround the imaging area TH. The imaging area TH that transmits imaging light may be a through hole that penetrates from the front surface to the back surface of the display device 1h, or may be an area made only of a transparent material so as to transmit imaging light. The imaging light is arranged so as to overlap with the imaging area TH of the display device 1h in a plan view, and is reflected light from a subject that is necessary for capturing an image with an imaging element (not shown) that is arranged on the back side of the display device 1h.

The non-display area NDA1 and the non-display area NDA2 of the display device 1h may each have the same configuration as the non-display area NDA1 described above in embodiment 1, or may each have the same configuration as the non-display area NDA1 described above in embodiment 5.

In this embodiment, an example is described in which the imaging area TH is circular and the non-display area NDA2 is also formed in a circular shape, but this is not limited to this, and the imaging area TH may be, for example, rectangular, and the non-display area NDA2 may also be formed in a rectangular shape.

17, since the non-display area NDA2 is an area where no display is performed, it is preferable that the non-display area NDA2 is not provided wider than necessary. Therefore, when the shape of the pixel PIX is rectangular as in this embodiment, it is preferable that the width of the non-display area NDA2 is formed to be equal to or less than the diagonal length of the pixel PIX. In this embodiment, an example is given in which the widths H1', H2', and H3' of the non-display area NDA2 are formed to be equal to or less than the diagonal length of the pixel PIX, but this is not limited thereto, and the widths H1', H2', and H3' of the non-display area NDA2 may be formed to be equal to or less than the width in the second direction D2 of the pixel PIX, or may be formed to be equal to or less than the diagonal length of the pixel PIX. In addition, for example, the widths H1', H2', and H3' of the non-display area NDA2 may be formed to be equal to or less than 50 μm, and it is preferable that they are formed to be equal to or more than 5 μm and equal to or less than 50 μm. By setting the width of the non-display area NDA2 within the above-mentioned range, the display area DA of the display device 1h can be made wider, and the display device 1h can be realized in which the light-emitting elements provided around the end DAE' of the display area DA emit light brighter than intended, suppressing the appearance of bright lines.

[Additional Notes]
The present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. The technical scope of the present disclosure also includes embodiments obtained by appropriately combining the technical means disclosed in the different embodiments. Furthermore, new technical features can be formed by combining the technical means disclosed in the respective embodiments.

This disclosure can be used in display devices.

1, 1a to 1h Display device 2, 2'

Substrate

5R, 5R' Red light emitting element (first light emitting element)
5G, 5G' Green light-emitting element (second light-emitting element)
5B, 5B' Blue light emitting element (third light emitting element)
6R, 6G, 6B, 6R', 6G', 6B' Non-light-emitting charge transfer element 6Ra, 6Ga, 6Ba Non-light-emitting charge transfer element 6Ra', 6Ga', 6Ba' Non-light-emitting charge transfer element 6Rb, 6Gb, 6Bb Non-light-emitting charge transfer element 6Rb', 6Gb', 6Bb' Non-light-emitting charge transfer element 8R Red light-emitting layer (first light-emitting layer)
8G Green light-emitting layer (second light-emitting layer)
8B Blue light-emitting layer (third light-emitting layer)
22 Lower electrode (anode)
22' Lower electrode (cathode)
24 Hole injection layer (charge transfer layer)
25 Hole transport layer (charge transfer layer)
26 Electron transport layer (charge transfer layer)
27 Electron injection layer (charge transfer layer)
28 First upper electrode layer (cathode)
28a: Second upper electrode layer (resistance adjusting layer)
28' First upper electrode layer (anode)
28a' Second upper electrode layer (resistance adjusting layer)
28c, 28c' Resistance adjusting layer M1 First surface M2 Second surface M3 Third surface DA Display area NDA1 Non-display area (first non-display area)
NDA2 Non-display area (second non-display area)
GA Frame area DAE, DAE' Ends of display area RSUB Red subpixel GSUB Green subpixel BSUB Blue subpixel PIX Pixel DRSUB First dummy subpixel DGSUB Second dummy subpixel DBSUB Third dummy subpixel H1, H1', H2, H2', H3, H3' Width of non-display area TR1 Drive transistor TR2 Selection transistor SL Scanning signal line DL Data signal line TH Imaging area

Claims

A substrate;
a display region on the substrate, the display region including a plurality of pixels each including a plurality of sub-pixels;
a non-display area on the substrate, the non-display area including a plurality of dummy sub-pixels provided along an edge of the display area and being continuous with the display area;
A plurality of lower electrodes provided in each of the display area and the non-display area;
a charge transport layer which is a single continuous layer provided across the display area and the non-display area;
A first upper electrode layer provided in the display area;
A second upper electrode layer provided in the non-display area;
a light-emitting element provided in each of the plurality of sub-pixels, the light-emitting element including, in this order from the substrate side, the lower electrode, the charge transfer layer, a light-emitting layer, and the first upper electrode layer;
a non-light-emitting charge transfer element provided in each of the plurality of dummy sub-pixels, the non-light-emitting charge transfer element including, in this order from the substrate side, the lower electrode, the charge transfer layer, a light-emitting layer, and the second upper electrode layer;
the non-light-emitting charge transfer element is provided with a resistance adjustment layer between a first surface of the charge transfer layer facing the light-emitting layer and a second surface of the second upper electrode layer facing away from the substrate, the resistance adjustment layer having a resistivity higher than that of the first upper electrode layer and being 1× 10 Ω·cm or less.
the first upper electrode layer and the second upper electrode layer are electrically connected to each other,
The display device according to claim 1 , wherein the resistance adjusting layer is the second upper electrode layer.
the first upper electrode layer is also provided in the non-display area as one continuous layer,
The display device according to claim 2 , wherein in the non-display region, the second upper electrode layer and the first upper electrode layer are laminated in this order from the substrate side.
the first upper electrode layer and the second upper electrode layer are one continuous layer formed of the same material,
The display device according to claim 1 , wherein the resistance adjusting layer is provided between the first surface and a third surface which is a surface of the second upper electrode layer on the light emitting layer side.
the first upper electrode layer and the second upper electrode layer are electrically isolated from each other;
the resistance adjusting layer is the second upper electrode layer,
a first voltage is applied to the first upper electrode layer via a first wiring;
a second voltage is applied to the second upper electrode layer via a second wiring;
The display device according to claim 1 , wherein the first voltage and the second voltage are the same voltage.
the lower electrode is an anode;
the first upper electrode layer and the second upper electrode layer are cathodes;
The display device according to claim 1 , wherein the charge transfer layer is at least one of a hole injection layer and a hole transport layer.
The display device according to claim 6, wherein at least one of an electron injection layer and an electron transport layer is provided between the light-emitting layer and the first upper electrode layer in the display area, and between the light-emitting layer and the second upper electrode layer in the non-display area.
the lower electrode is a cathode,
the first upper electrode layer and the second upper electrode layer are anodes;
The display device according to claim 1 , wherein the charge transfer layer is at least one of an electron injection layer and an electron transport layer.
The display device according to claim 8, wherein at least one of a hole injection layer and a hole transport layer is provided between the light-emitting layer and the first upper electrode layer in the display area, and between the light-emitting layer and the second upper electrode layer in the non-display area.
The display device according to any one of claims 1 to 9, wherein the non-display area is provided so as to surround the display area.
the non-display area includes a first non-display area and a second non-display area,
an imaging area that transmits imaging light is provided inside the display area,
the first non-display area is provided so as to surround the outer periphery of the display area,
The display device according to claim 1 , wherein the second non-display area is provided so as to surround the imaging area.