WO2024154195A1

WO2024154195A1 - Light emitting device and display device

Info

Publication number: WO2024154195A1
Application number: PCT/JP2023/000992
Authority: WO
Inventors: 伸郎齊藤
Original assignee: シャープディスプレイテクノロジー株式会社
Priority date: 2023-01-16
Filing date: 2023-01-16
Publication date: 2024-07-25

Abstract

A light emitting device (1) comprises: an optical waveguide (2); a light emitting element (3) that overlaps with the optical waveguide (2) in plan view; and a light receiving sensor (4) that overlaps with the optical waveguide (2) and does not overlap with the light emitting element (3) in plan view.

Description

Light emitting device and display device

This disclosure relates to a light-emitting device and a display device.

Predictive compensation for light-emitting elements only compensates for deterioration over time based on a prediction. For this reason, there is a need to perform external compensation based on the deterioration state of the light-emitting element, and in order to optimize external compensation, there is a need for a configuration in which a light-receiving sensor is provided for each light-emitting element.

Patent Document 1 discloses a configuration in which an organic EL element is formed on a transparent substrate, and an optical sensor is formed between the transparent substrate and the organic EL element, or on the transparent substrate on the opposite side to the organic EL element.

JP 2012-186218 A (Published on September 27, 2012)

Normally, the refractive index of the layer containing the light-emitting element is different from that of the outside, so light emitted at a large angle is reflected at the boundary or surface, making it difficult to extract to the outside. On the other hand, light emitted at a small angle is easy to extract to the outside. In the configuration disclosed in Patent Document 1, the light sensor overlaps with the organic EL element in a planar view, so some of the light emitted at a small angle enters the light sensor. Therefore, the amount of light that is easy to extract is reduced by the amount that enters the light sensor, resulting in a problem of reduced light extraction efficiency.

The light emitting device according to one aspect of the present disclosure includes an optical waveguide, a light emitting element that overlaps with the optical waveguide in a planar view, and a light receiving sensor that overlaps with the optical waveguide but does not overlap with the light emitting element in a planar view.

According to one aspect of the present disclosure, the light extraction efficiency can be improved in a light emitting device that includes a light emitting element and a light receiving sensor.

1 is a schematic plan view illustrating an example of a configuration of a light-emitting device according to an embodiment of the present disclosure. 1 is a schematic cross-sectional view showing an example of a configuration of a light-emitting device according to an embodiment of the present disclosure. 3 is a circuit diagram showing an example in which the pixel circuit and the light receiving circuit shown in FIG. 2 have the same circuit configuration. 4 is a circuit diagram showing an example of an operation when data is written from a data line to a pixel circuit in the circuit configuration shown in FIG. 3. FIG. 4 is a circuit diagram showing an example of an operation when a light receiving element emits light in the circuit configuration shown in FIG. 3. FIG. 3 is a circuit diagram showing an example of a different circuit configuration of the pixel circuit and the light receiving circuit shown in FIG. 2. 7 is a circuit diagram showing an example of an operation when data is written from a data line to a pixel circuit in the circuit configuration shown in FIG. 6. FIG. 7 is a circuit diagram showing an example of the operation when a light receiving element emits light in the circuit configuration shown in FIG. 6. FIG. 7 is a circuit diagram showing an example of an operation when data is read out from a light receiving circuit to a data line in the circuit configuration shown in FIG. 6. FIG. 1 is a schematic cross-sectional view showing an example of a configuration of a light-emitting device according to an embodiment of the present disclosure. 1 is a schematic cross-sectional view showing an example of a configuration of a light-emitting device according to an embodiment of the present disclosure. 1 is a schematic cross-sectional view showing an example of a configuration of a light-emitting device according to an embodiment of the present disclosure. 1 is a schematic cross-sectional view showing an example of a configuration of a light-emitting device according to an embodiment of the present disclosure. 1 is a schematic cross-sectional view showing an example of a configuration of a light-emitting device according to an embodiment of the present disclosure. FIG. 1 is a schematic diagram illustrating an example of a configuration of a display device according to an embodiment of the present disclosure. 16 is a schematic plan view showing an example of the configuration of the display unit shown in FIG. 15. 16 is a schematic plan view showing another example of the configuration of the display unit shown in FIG. 15. 16 is a schematic plan view showing yet another example of the configuration of the display unit shown in FIG. 15 . FIG. 1 is a schematic diagram illustrating an example of a configuration of a display device according to an embodiment of the present disclosure.

[Embodiment 1]
(Configuration of the Light Emitting Device)
Fig. 1 is a schematic plan view showing an example of the configuration of a light-emitting device according to an embodiment of the present disclosure. As shown in Fig. 1, the light-emitting device 1 includes an optical waveguide 2, a light-emitting element 3 overlapping the optical waveguide 2 in a planar view, and a light-receiving sensor 4 overlapping the optical waveguide 2 in a planar view but not overlapping the light-emitting element 3 in a planar view. The light-emitting element 3 emits light when a voltage or current is applied to the light-emitting element 3. The light-receiving sensor 4 generates a photoelectromotive force when light is incident on the light-receiving sensor 4.

In the configuration disclosed herein, the light receiving sensor 4 is located to the side of the light emitting element 3 in a planar view, so that light guided by the optical waveguide 2 is incident on the light receiving sensor 4. Light incident from the light emitting element 3 to the optical waveguide 2 at an angle smaller than the critical angle crosses the optical waveguide 2 and is easily extracted to the outside. On the other hand, light incident at an angle larger than the critical angle is reflected on the surface or inside of the optical waveguide 2, tends to propagate along the optical waveguide 2, and is difficult to extract to the outside. Therefore, advantageously, since light that is difficult to extract to the outside is incident on the light receiving sensor 4, the efficiency of extracting light from the light emitting device 1 to the outside can be improved.

FIG. 2 is a schematic cross-sectional view showing an example of the configuration of a light-emitting device according to an embodiment of the present disclosure. FIG. 2 corresponds to the A-A cross-sectional view of FIG. 1. As shown in FIG. 2, the light-emitting element 3 may include a pixel electrode PE that overlaps with the optical waveguide 2 in a planar view, a first electrode E1 located between the optical waveguide 2 and the pixel electrode PE, and an emission layer EM located between the pixel electrode PE and the first electrode E1. The light-receiving sensor 4 may include a sensor electrode SE that overlaps with the optical waveguide 2 in a planar view and does not overlap with the pixel electrode PE in a planar view, a second electrode E2 located between the optical waveguide 2 and the sensor electrode SE, a first generation layer G1 located between the sensor electrode SE and the second electrode E2 and generating first carriers, and a second generation layer G2 located between the sensor electrode SE and the second electrode E2 and generating second carriers of the opposite polarity to the first carriers.

The first carrier is either a hole or an electron, and the second carrier is the other of the hole and the electron. In the example shown in FIG. 1, the first generating layer G1 is a layer in which holes are generated as charge carriers (hereinafter referred to as the "hole generating layer"), and the second generating layer G2 is a layer in which electrons are generated as charge carriers (hereinafter referred to as the "electron generating layer"). Not limited to this, the scope of the present disclosure also includes a configuration in which the first generating layer G1 is an electron generating layer and the second generating layer G2 is a hole generating layer.

The hole generating layer may include a p-type semiconductor or a hole transporting organic material, and the electron generating layer may include an n-type semiconductor or an electron transporting organic material. A pn junction is formed between the hole generating layer and the electron generating layer, and light incident on or near the pn junction generates one or more pairs of holes and electrons. In order to increase the efficiency of generating hole-electron pairs, it is preferable that the first generating layer G1 is in direct contact with the second generating layer G2.

The light-emitting element 3 may include a first transport layer T1 located between the pixel electrode PE and the first electrode E1 and transporting a first carrier, and a second transport layer T2 located between the pixel electrode PE and the first electrode E1 and transporting a second carrier. The first transport layer T1 may be formed from the same layer made of the same material as the first generation layer G1, and the second transport layer T2 may be formed from the same layer made of the same material as the second generation layer G2. Advantageously, the number of layers stacked in the light-emitting device 1 can be reduced by sharing at least some layers between the light-emitting element 3 and the light-receiving sensor 4.

In this disclosure, "a certain layer is formed from the same layer as another certain layer" means that it is possible to presume that the former layer and the latter layer are formed in the same process. If the material and thickness of the former layer are substantially the same as the material and thickness of the latter layer, it is possible to presume that the former layer is formed in the same process as the latter layer, unless there is a basis for presuming that the former layer and the latter layer are formed in different processes.

In this disclosure, "a material is substantially the same as another material" includes not only the case where the former material and the latter material are completely identical, but also the case where the latter material can be obtained by subjecting the former material to any processing such as doping and exposure, and the case where the former material can be obtained by subjecting the latter material to any processing.

In this disclosure, "the thickness of a layer is substantially the same as the thickness of another layer" includes not only the case where the thickness of the latter layer is completely the same as the thickness of the former layer, but also the case where the difference between the thickness of the former layer and the thickness of the latter layer is sufficiently small. Usually, a difference of 10% or less of the larger thickness is permitted.

The first transport layer T1 may be continuous with the first generation layer G1, and the second transport layer T2 may be continuous with the second generation layer G2. In other words, the first generation layer G1 and the second generation layer G2 may extend between the pixel electrode PE and the first electrode E1, respectively, and may function as the first transport layer T1 and the second transport layer T2. Advantageously, the layer that is continuous from the light-emitting element 3 to the light-receiving sensor 4 can help guide a portion of the light emitted by the light-emitting element 3 to the light-receiving sensor 4. Not limited to this, the first transport layer T1 may be discontinuous with the first generation layer G1, and the second transport layer T2 may be discontinuous with the second generation layer G2, due to a film break due to a step or patterning, etc.

The first transport layer T1 is located between the pixel electrode PE and the light-emitting layer EM, and the first structure between the pixel electrode PE and the first transport layer T1 may be the same as the second structure between the sensor electrode SE and the first generating layer G1. The second transport layer T2 is located between the first electrode E1 and the light-emitting layer EM, and the third structure between the first electrode E1 and the second transport layer T2 may be the same as the fourth structure between the second electrode E2 and the second generating layer G2. Advantageously, the number of layers in the light-emitting device 1 can be further reduced by sharing more layers between the light-emitting element 3 and the light-receiving sensor 4.

In this disclosure, "the structure between a pair of layers is the same as the structure between another pair of layers" has the following meanings. First, it means that if there is no layer between the former, there is also no layer between the latter. Second, it means that if there is only one layer between the former, there is only one corresponding layer between the latter, and the material and thickness of the one layer between the former are approximately the same as the material and thickness of the one layer between the latter. Third, it means that if there are n layers (n is an integer of 2 or more) overlapping between the former, the corresponding n layers between the latter are overlapping in the same order, and the material and thickness of each layer between the former are approximately the same as the material and thickness of the corresponding layer between the latter.

The first structure may be continuous with the second structure. Also, the third structure may be continuous with the fourth structure. This advantageously allows more layers to be continuous from the light-emitting element 3 to the light-receiving sensor 4, helping to guide some of the light emitted by the light-emitting element 3 to the light-receiving sensor 4. For example, the hole injection layer HIL may be continuous between the pixel electrode PE and the first transport layer T1 and between the sensor electrode SE and the first generation layer G1. Also, for example, the electron injection layer EIL may be continuous between the first electrode E1 and the second transport layer T2 and between the second electrode E2 and the second generation layer G2.

The sensor electrode SE may be electrically separated from the pixel electrode PE, and the second electrode E2 may be electrically connected to the first electrode E1. This allows the light emitting element 3 to emit light and the light receiving sensor 4 to receive light simultaneously and independently. The first electrode E1 may be continuous with the second electrode E2. The continuous first electrode E1 and second electrode E2 are included in the so-called "common electrode" or "counter electrode". The sensor electrode SE may be formed from the same layer as the pixel electrode PE.

In short, each layer constituting the light-emitting element 3 may extend to the light-receiving sensor 4, except for the pixel electrode PE and the light-emitting layer EM.

The light emitting device 1 may further include an edge cover film EC that covers at least a portion of the edge of the pixel electrode PE and has an opening AP that overlaps in a planar view with a portion of the pixel electrode PE and at least a portion of the sensor electrode SE. The edge cover film EC may cover at least a portion of the edge of the sensor electrode SE.

The light-emitting element 3 may be a light-emitting diode, and the light-receiving sensor 4 may be a photodiode. The light-emitting element 3 may be an organic light-emitting diode (OLED) in which the light-emitting layer EM contains an organic light-emitting material, or a quantum dot light-emitting diode (QLED) in which the light-emitting layer EM contains quantum dots. The light-receiving sensor 4 may be an organic photodiode in which the first generating layer G1 and the second generating layer G2 contain an organic material, or an inorganic photodiode in which the first generating layer G1 and the second generating layer G2 contain an inorganic material.

The light emitting device 1 may further include a substrate CP, and the light emitting element 3 and the light receiving sensor 4 may be located between the substrate CP and the optical waveguide 2. The substrate CP may be a circuit board including a support substrate BP and a circuit layer CL formed on the support substrate.

The optical waveguide 2 can guide a portion of the light emitted by the light-emitting element 3 to the light-receiving sensor 4. Of the light generated in the light-emitting layer EM, light that is incident on the optical waveguide 2 at an angle smaller than the critical angle crosses the optical waveguide 2 and is radiated to the outside of the light-emitting device 1. On the other hand, light that is incident on the optical waveguide 2 at an angle larger than the critical angle passes through the optical waveguide 2 and is guided to the light-receiving sensor 4. Therefore, advantageously, the light-receiving sensor 4 does not cause a decrease in the light extraction efficiency because it takes in light that is difficult to extract to the outside.

The optical waveguide 2 may include at least a portion of the sealing layer TFE that seals the light-emitting element 3 and the light-receiving sensor 4, or may include the entirety of the sealing layer TFE. Furthermore, one or more layers located between the substrate CP and the sealing layer TFE may help guide a portion of the light emitted by the light-emitting element 3 to the light-receiving sensor 4. In the example shown in FIG. 2, the entire sealing layer TFE is the optical waveguide 2. Therefore, it is denoted by the symbol "TFE(2)".

The sealing layer TFE may be a thin sealing layer, and may include, for example, a first inorganic sealing film N1, a second inorganic sealing film N2, and an organic sealing film O1 located between the first inorganic sealing film N1 and the second inorganic sealing film N2. The first inorganic sealing film N1 and the second inorganic sealing film N2 may include, for example, one or more selected from the group consisting of silicon nitride and silicon oxide. The organic sealing film O1 is preferably made of a transparent material having a smaller refractive index than the first inorganic sealing film N1 and the second inorganic sealing film N2. For example, when the first inorganic sealing film N1 and the second inorganic sealing film N2 are made of silicon oxide, the organic sealing film O1 may include one or more selected from the group consisting of polyacrylic resins.

(Circuit configuration)
The light emitting device 1 may further include a pixel circuit C1 that controls the light emission of the light emitting element 3 by controlling the applied voltage or current, and a light receiving circuit C2 that detects the light received by the light receiving sensor 4 by measuring the generated electromotive force. The circuit configuration of the light receiving circuit C2 may be the same as or different from the circuit configuration of the pixel circuit C1. The pixel circuit C1 and the light receiving circuit C2 may be formed in the substrate CP.

When the circuit configuration of one circuit is the same as the circuit configuration of another circuit, it means that the circuit elements of the former are equivalent to the circuit elements of the latter, and that the connection relationships between the circuit elements in the former are equivalent to the connection relationships between the circuit elements in the latter. Here, the circuit elements and connection relationships are considered to be equivalent even if their characteristic values are different. For example, two transistors with different threshold values and resistance values are equivalent circuit elements. Also, for example, two capacitors with different capacitances and geometric sizes are equivalent circuit elements. Also, for example, a light-emitting diode and a photodiode are equivalent circuit elements. Also, for example, parasitic capacitance and wiring resistance may be ignored.

FIG. 3 is a circuit diagram showing an example in which the pixel circuit and the light receiving circuit shown in FIG. 2 have the same circuit configuration. As shown in FIG. 3, the pixel circuit C1 may include a write transistor T11, an amplifying transistor T12, a read transistor T13, a light emitting transistor T14, an initialization transistor T15, and a storage capacitor M11. Similarly, the light receiving circuit C2 may include a write transistor T21, an amplifying transistor T22, a read transistor T23, a light receiving transistor T24, an initialization transistor T25, and a storage capacitor M21.

The gate signal line GL connected to the pixel circuit C1 and the gate signal line GL connected to the light receiving circuit C2 are separate and can be supplied with control signals independently. The monitor signal line ML connected to the pixel circuit C1 and the monitor signal line ML connected to the light receiving circuit C2 are separate and can be supplied with control signals independently.

The light-emitting signal line EL connected to the pixel circuit C1 and the light-emitting signal line EL connected to the light-receiving circuit C2 may be separate or connected to each other. The pixel circuit C1 and the light-receiving circuit C2 may share the light-emitting signal line EL. The pixel circuit C1 and the light-receiving circuit C2 may share the power lines that supply the drain side power supply potential ELVDD, the source side power supply potential ELVSS, and the initialization potential Vini, respectively.

FIG. 4 is a circuit diagram showing an example of the operation when data is written from a data line to a pixel circuit in the circuit configuration shown in FIG. 3. FIG. 5 is a circuit diagram showing an example of the operation when the light receiving element is emitting light in the circuit configuration shown in FIG. 3. FIG. 4 and FIG. 5 show write transistors T11, T21, read transistors T13, T23, light emitting transistor T14, light receiving transistor T24, and initialization transistors T15, T25 as switching elements.

As shown in FIG. 4, after the pixel circuit C1 and the light receiving circuit C2 are initialized, in the pixel circuit C1, the write transistor T11 and the initialization transistor T15 are brought into a conducting state, and the read transistor T13 and the light emitting transistor T14 are brought into a non-conducting state. This allows data to be written from the data signal line DL to the gate electrode of the amplifier transistor T12 and one electrode of the storage capacitor M11 through the write transistor T11, and the initialization potential Vini to be written to the opposite electrode of the storage capacitor M11 through the initialization transistor T15. During writing to the storage capacitor M11, the write transistor T21 and the read transistor T23 in the light receiving circuit C2 may be brought into a non-conducting state.

As shown in FIG. 5, in the pixel circuit C1, the write transistor T11, the read transistor T13, and the initialization transistor T15 are then de-energized, and the light-emitting transistor T14 is energized. This allows the drain-side power supply potential ELVDD to be applied to the pixel electrode PE through the amplification transistor T12 and the light-emitting transistor T14, causing the light-emitting element 3 to emit light. The voltage applied to the pixel electrode PE and the light-emitting brightness of the light-emitting element 3 are determined according to the gate voltage of the amplification transistor T12, i.e., the data written to one electrode of the storage capacitor M11. During the emission of the light-emitting element 3, in the light-receiving circuit C2, the write transistor T21 and the initialization transistor T25 may be de-energized, and the read transistor T23 and the light-receiving transistor T24 may be energized. This allows the charge generated in the light-receiving sensor 4 to be output to the data signal line DL through the sensor electrode SE, the light-receiving transistor T24, and the read transistor T23.

Alternatively, while the light-emitting element 3 is emitting light, in the light-receiving circuit C2, the write transistor T21, read transistor T23, and initialization transistor T25 may be made non-conductive, and the light-receiving transistor T24 may be made conductive. This allows the charge generated in the light-receiving sensor 4 to be stored in the opposite electrode of the storage capacitor M21 through the sensor electrode SE and the light-receiving transistor T24. After the light-emitting element 3 emits light, the read transistor T23 can be made conductive, and the charge stored in the storage capacitor M21 can be output to the data signal line DL through the read transistor T23.

The pixel circuit C1 and the light receiving circuit C2 may share some of the circuit elements. For example, the pixel circuit C1 and the light receiving circuit C2 may share one transistor as the initialization transistors T15 and T25.

The pixel circuit C1 and the light receiving circuit C2 may share a portion of the wiring that connects them. For example, the light emitting device 1 may further include a data signal line DL that supplies data specifying the light emission brightness of the light emitting element 3 to the pixel circuit C1, and the light receiving circuit C2 may output the detection result of the light receiving sensor 4 through the data signal line DL.

FIG. 6 is a circuit diagram showing an example in which the pixel circuit and light receiving circuit shown in FIG. 2 have different circuit configurations. As shown in FIG. 6, the pixel circuit C1 may include initialization transistors T31 and T37, write transistors T32 and T33, an amplification transistor T34, light emitting transistors T35 and T36, and a storage capacitor M3. The light receiving circuit C2 may include initialization transistors T41 and T45, an amplification transistor T43, a readout transistor T42, and a light receiving transistor T44.

FIG. 7 is a circuit diagram showing an example of the operation when data is written from the data line to the pixel circuit in the circuit configuration shown in FIG. 6. FIG. 8 is a circuit diagram showing an example of the operation when the light receiving element is emitting light in the circuit configuration shown in FIG. 6. FIG. 9 is a circuit diagram showing an example of the operation when data is read from the light receiving circuit to the data line in the circuit configuration shown in FIG. 6. FIGS. 7, 8 and 9 show initialization transistors T31, T37, T41, T45, write transistors T32, T33, light emitting transistors T35, T36, read transistor T42 and light receiving transistor T44 as switching elements.

As shown in FIG. 7, after the pixel circuit C1 and the light receiving circuit C2 are initialized, in the pixel circuit C1, the write transistors T32 and T33 are brought into a conducting state, and the initialization transistor T31 and the light emitting transistors T35 and T36 are brought into a non-conducting state. This allows data to be written from the data signal line DL through the write transistor T33, the amplifying transistor T34, and the write transistor T21 to the gate electrode of the amplifying transistor T34 and one electrode of the memory capacitor M3. During writing to the memory capacitor M3, the read transistor T42 in the light receiving circuit C2 may be brought into a non-conducting state.

As shown in FIG. 8, next, in pixel circuit C1, initialization transistors T31, T37 and write transistors T32, T33 are turned off, and light-emitting transistors T35, T36 are turned on. This allows the drain-side power supply potential ELVDD to be applied to pixel electrode PE through light-emitting transistor T35, amplification transistor T34, and light-emitting transistor T36, causing light-emitting element 3 to emit light. While light-emitting element 3 is emitting light, in light-receiving circuit C2, initialization transistors T41, T45 and read transistor T42 may be turned off, and light-receiving transistor T44 may be turned on. This allows charge generated in light-receiving sensor 4 to be accumulated in the gate electrode of amplification transistor T43 through sensor electrode SE and light-receiving transistor T44.

As shown in FIG. 9, after the light-emitting element 3 emits light, in the light-receiving circuit C2, the read transistor T42 is turned on, and the drain power supply potential ELVDD can be output to the data line DL through the read transistor T42 and the amplification transistor T43. The output voltage to the data line DL is determined according to the gate voltage of the amplification transistor T43, i.e., the amount of charge stored in the gate electrode of the amplification transistor T43.

The pixel circuit C1 and the light receiving circuit C2 may share some of the circuit elements. For example, the pixel circuit C1 and the light receiving circuit C2 may share one transistor as the initialization transistors T37 and T41. The pixel circuit C1 and the light receiving circuit C2 may share some of the wiring that connects them. For example, the pixel circuit C1 and the light receiving circuit C2 may share the data signal line DL.

[Embodiment 2]
Other embodiments of the present disclosure will be described below. For convenience of explanation, the same reference numerals will be given to components having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

FIG. 10 is a schematic cross-sectional view showing an example of the configuration of a light-emitting device according to an embodiment of the present disclosure. As shown in FIG. 10, the optical waveguide 2 may include a scatterer SP that overlaps with the light-receiving sensor 4 in a planar view. The scatterers SP may be distributed so as not to overlap with the light-emitting element 3 in a planar view. For example, the organic sealing film O1 may include a plurality of scatterers SP and a filling material FM that fills the spaces between the scatterers SP.

[Embodiment 3]
11 is a schematic cross-sectional view showing an example of the configuration of a light emitting device according to an embodiment of the present disclosure. As shown in Fig. 11, the optical waveguide 2 may include a first portion P1 overlapping with the light emitting element 3 in a plan view, and a second portion P2 overlapping with the light receiving sensor 4 in a plan view and having a refractive index larger than that of the first portion P1.

For example, the organic sealing film O1 may have a portion P3 included in the first portion P1 and made of a first transparent material, and a portion P4 included in the second portion P2 and made of a second transparent material having a higher refractive index than the first transparent material. The first inorganic sealing film N1 and the second inorganic sealing film N2 may each be made of the same material across the first portion P1 and the second portion P2. In this example, the average refractive index of the second portion P2 is higher than the average refractive index of the first portion P1.

This embodiment 3 can be combined with the above-described embodiment 2. For example, the scatterers SP may be distributed in the second portion P2 of the optical waveguide 2 (or the portion P4 of the organic sealing film O1).

[Embodiment 4]
Fig. 12 is a schematic cross-sectional view showing an example of the configuration of a light-emitting device according to an embodiment of the present disclosure. As shown in Fig. 12, the light-emitting device 1 may further include a light reflecting portion RF that overlaps with the light-receiving sensor 4 in a plan view and reflects the propagating light of the optical waveguide 2. The light reflecting portion RF is provided so as not to overlap with the light-emitting element 3 in a plan view.

This embodiment 4 can be combined with one or more of the above-mentioned embodiments 1 to 3.

[Embodiment 5]
Fig. 13 is a schematic cross-sectional view showing an example of the configuration of a light-emitting device according to an embodiment of the present disclosure. As shown in Fig. 13, the light-emitting device 1 may further include a light-shielding part SH that overlaps with the light-receiving sensor 4 in a plan view and blocks external light. The light-shielding part SH is provided so as not to overlap with the light-emitting element 3 in a plan view.

This embodiment 5 can be combined with any one or more of the above-mentioned embodiments 1 to 3. Furthermore, this embodiment 5 can be combined with the above-mentioned embodiment 4. For example, the light shielding portion SH may function as the light reflecting portion RF. Also, for example, the light reflecting portion RF may be located between the light shielding portion SH and the optical waveguide 2.

[Embodiment 6]
14 is a schematic cross-sectional view showing an example of the configuration of a light-emitting device according to an embodiment of the present disclosure. As shown in FIG. 14, the light-emitting device 1 may further include a light-shielding bank SB that surrounds the light-emitting element 3 and the light-receiving sensor 4 in a plan view and blocks external light. The light-shielding bank SB may be included in the edge cover film EC. The light-shielding bank SB may be a black bank that absorbs light, and may be formed from a resin to which a pigment is added. The pigment may include carbon powder.

In addition, or alternatively, the light emitting device 1 may further include a light-transmitting bank TB that is located between the light emitting element 3 and the light receiving sensor 4 and allows the light emitted by the light emitting element 3 to pass through. The light-transmitting bank TB may be included in the edge cover film EC.

This embodiment 6 can be combined with one or more of the above-mentioned embodiments 1 to 5.

[Embodiment 7]
15 is a schematic diagram showing an example of the configuration of a display device according to an embodiment of the present disclosure. As shown in FIG. 15, the display device 100 includes at least one light-emitting device 1. The display device 100 includes, for example, a display unit 10 having a plurality of sub-pixels PX and a drive circuit 20 that drives the display unit 10. At least one of the sub-pixels PX includes a light-emitting device 1. The light-emitting device 1 included in the display device 100 may be the light-emitting device 1 according to any one of the above-mentioned embodiments 1 to 6, the light-emitting device 1 according to some combination of the above-mentioned embodiments 1 to 6, or a light-emitting device 1 modified or improved therefrom.

The display device 100 may further include a control unit CT that controls the voltage or current applied to the light-emitting element 3 so as to compensate for deterioration of the light-emitting element 3 based on the detection result of the light-receiving sensor 4. This compensates for the decrease in luminance of the light-emitting element 3, and the display quality of the display device 100 can be maintained and improved. The control unit CT may be built into the drive circuit 20.

FIG. 16 is a schematic plan view showing an example of the configuration of the display unit shown in FIG. 15. As shown in FIG. 16, the display unit 10 may include a red subpixel RX, a green subpixel GX, and a blue subpixel BX. The red subpixel RX includes a light-emitting element 3R that emits red light, a light-receiving sensor 4R that detects the light emitted by the light-emitting element 3R, and an optical waveguide 2 (not shown). The green subpixel GX includes a light-emitting element 3G that emits green light, a light-receiving sensor 4G that detects the light emitted by the light-emitting element 3G, and an optical waveguide 2 (not shown). The blue subpixel BX includes a light-emitting element 3B that emits blue light, a light-receiving sensor 4B that detects the light emitted by the light-emitting element 3B, and an optical waveguide 2 (not shown).

The red subpixel RX, the green subpixel GX, and the blue subpixel BX may have edge cover films EC, and each edge cover film EC may be continuous with each other. The edge cover film EC may include a light-transmitting bank TB and a light-shielding bank SB.

FIG. 17 is a schematic plan view showing another example of the configuration of the display unit shown in FIG. 15. As shown in FIG. 17, a red subpixel RX, a green subpixel GX, and a blue subpixel BX may be arranged. FIG. 18 is a schematic plan view showing yet another example of the configuration of the display unit shown in FIG. 15. As shown in FIG. 18, light-emitting

elements

3R, 3G, and 3B may surround corresponding light-receiving

sensors

4R, 4G, and 4B, respectively. The configuration of the display unit 10 is not limited to the examples shown in FIGS. 16 to 18.

[Embodiment 8]
19 is a schematic diagram showing an example of the configuration of a display device according to an embodiment of the present disclosure. As shown in FIG. 19, the display device 100 includes at least one light-emitting device 1. The display device 100 may further include an external light sensor LS and a control unit CT that controls the voltage or current applied to the light-emitting element 3 so as to compensate for deterioration of the light-emitting element 3 based on the detection result of the light receiving sensor 4 and the detection result of the external light sensor SL. This compensates for the decrease in luminance of the light-emitting element 3 in consideration of external light, and the display quality of the display device 100 can be maintained and improved. The control unit CT may be built into the drive circuit 20.

This disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. The technical scope of this disclosure also includes embodiments obtained by appropriately combining the technical means disclosed in different embodiments. Furthermore, new technical features can be formed by combining the technical means disclosed in each embodiment.

1 Light emitting device 2 Optical waveguide 3 Light emitting element 4 Light receiving sensor 100 Display device AP Opening C1 Pixel circuit C2 Light receiving circuit CP Substrate CT Control unit DL Data signal line E1 First electrode E2 Second electrode EC Edge cover film G1 First generation layer G2 Second generation layer EM Light emitting layer LS External light sensor P1 First portion P2 Second portion PE Pixel electrode RF Light reflecting portion SB Light shielding bank SE Sensor electrode SP Scatterer SH Light shielding portion T1 First transport layer T2 Second transport layer T37, T41 Initialization transistor TFE Sealing layer

Claims

An optical waveguide;
a light emitting element overlapping the optical waveguide in a plan view;
a light receiving sensor that overlaps the optical waveguide but does not overlap the light emitting element in a plan view.
the light-emitting element includes a pixel electrode overlapping the optical waveguide in a plan view, a first electrode positioned between the optical waveguide and the pixel electrode, and a light-emitting layer positioned between the pixel electrode and the first electrode;
2. The light-emitting device of claim 1, wherein the light-receiving sensor includes a sensor electrode that overlaps with the optical waveguide in a planar view but does not overlap with the pixel electrode in a planar view, a second electrode located between the optical waveguide and the sensor electrode, a first generation layer located between the sensor electrode and the second electrode and in which first carriers are generated, and a second generation layer located between the sensor electrode and the second electrode and in which second carriers of opposite polarity to the first carriers are generated.
The light emitting device of claim 2, wherein the first generation layer is in direct contact with the second generation layer.
the light-emitting element includes a first transport layer located between the pixel electrode and the first electrode and transporting the first carriers, and a second transport layer located between the pixel electrode and the first electrode and transporting the second carriers;
the first transport layer is formed from the same layer of the same material as the first generation layer;
4. The light emitting device according to claim 2, wherein the second transport layer is formed from the same layer made of the same material as the second generation layer.
the first transport layer is continuous with the first generation layer;
5. The light emitting device of claim 4, wherein said second transport layer is contiguous with said second generation layer.
The light-emitting device according to claim 2 or 3, wherein the first generation layer and the second generation layer extend between the pixel electrode and the first electrode, respectively.
the first transport layer is located between the pixel electrode and the light emitting layer, a first structure between the pixel electrode and the first transport layer being identical to a second structure between the sensor electrode and the first generation layer;
6. The light-emitting device of claim 4, wherein the second transport layer is located between the first electrode and the light-emitting layer, and a third structure between the first electrode and the second transport layer is identical to a fourth structure between the second electrode and the second generation layer.
the first structure is continuous with the second structure;
The light emitting device of claim 7 , wherein the third structure is contiguous with the fourth structure.
the sensor electrode is electrically isolated from the pixel electrode;
9. The light emitting device according to claim 2, wherein the second electrode is electrically connected to the first electrode.
The light-emitting device according to any one of claims 2 to 9, wherein the sensor electrode is formed from the same layer as the pixel electrode.
The light-emitting device according to any one of claims 2 to 10, further comprising an edge cover film that covers at least a portion of the edge of the pixel electrode and has an opening that overlaps with at least a portion of the pixel electrode and the sensor electrode in a plan view.
the light emitting element is a light emitting diode,
The light emitting device according to any one of claims 1 to 11, wherein the light receiving sensor is a photodiode.
The light-emitting device according to any one of claims 1 to 12, further comprising a substrate, the light-emitting element and the light-receiving sensor being positioned between the substrate and the optical waveguide.
The light emitting device according to any one of claims 1 to 13, wherein the optical waveguide guides a portion of the light emitted by the light emitting element to the light receiving sensor.
The light emitting device according to any one of claims 1 to 14, wherein the optical waveguide includes at least a portion of a sealing layer that seals the light emitting element and the light receiving sensor.
The light emitting device according to any one of claims 1 to 15, wherein the optical waveguide includes a scatterer that overlaps with the light receiving sensor in a plan view.
The light emitting device according to any one of claims 1 to 16, wherein the optical waveguide includes a first portion that overlaps with the light emitting element in a planar view, and a second portion that overlaps with the light receiving sensor in a planar view and has a refractive index greater than that of the first portion.
The light emitting device according to any one of claims 1 to 17, further comprising a light reflecting section that overlaps with the light receiving sensor in a plan view and reflects the light propagating through the optical waveguide.
The light-emitting device according to any one of claims 1 to 18, further comprising a light-shielding portion that overlaps the light-receiving sensor in a plan view and blocks external light.
The light emitting device according to any one of claims 1 to 19, further comprising a light shielding bank that surrounds the light emitting element and the light receiving sensor in a plan view and blocks external light.
A pixel circuit that controls the emission of the light emitting element and a light receiving circuit that detects the reception of light by the light receiving sensor,
21. The light emitting device according to claim 1, wherein the circuit configuration of the light receiving circuit is the same as the circuit configuration of the pixel circuit.
A pixel circuit that controls the emission of the light emitting element and a light receiving circuit that detects the reception of light by the light receiving sensor,
21. The light emitting device according to claim 1, wherein a circuit configuration of the light receiving circuit is different from a circuit configuration of the pixel circuit.
The light-emitting device according to claim 21 or 22, wherein the pixel circuit and the light-receiving circuit share one transistor as an initialization transistor.
a data signal line for supplying data for designating a light emission luminance of the light emitting element to the pixel circuit;
24. The light emitting device according to claim 21, wherein the light receiving circuit outputs a detection result of the light receiving sensor through the data signal line.
A display device comprising a light-emitting device according to any one of claims 1 to 24.
The display device according to claim 25, further comprising a control unit that controls the voltage or current applied to the light-emitting element so as to compensate for deterioration of the light-emitting element based on the detection result of the light-receiving sensor.
An external light sensor;
26. The display device according to claim 25, further comprising: a control unit that controls a voltage or current applied to the light-emitting element so as to compensate for deterioration of the light-emitting element based on a detection result of the light receiving sensor and a detection result of the external light sensor.