Display device

Abstract

To provide a display device including both a touch detection function and a fingerprint or vein shape imaging function.SOLUTION: A display device includes a first light-emitting element, a second light-emitting element, a light-receiving element, and a light shielding layer. The first light-emitting element and the light-receiving element are arranged side by side on the same plane. The light shielding layer is provided above the first light-emitting element and the light-receiving element. The second light-emitting element is provided above the light shielding layer. The first light-emitting element has a function for emitting visible light upward. The second light-emitting element has a function for emitting invisible light upward. The light-receiving element is a photoelectric conversion element that is sensitive to the visible light and the invisible light. In addition, the light shielding layer has a portion positioned between the first light-emitting element and the light-receiving element in a plan view, and the second light-emitting element overlaps with the light shielding layer in a plan view and is positioned further to the inside than the contour of the light shielding layer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] 1. Field of the Invention The present invention relates to a display device, an imaging device, and a touch panel.

[0002] Note that one embodiment of the present invention is not limited to the above technical field. Examples of the technical field of one embodiment of the present invention disclosed in this specification and the like include semiconductor devices, display devices, light-emitting devices, power storage devices, memory devices, electronic devices, lighting devices, input devices, input / output devices, driving methods thereof, and manufacturing methods thereof. A semiconductor device refers to any device that can function by utilizing semiconductor characteristics. [Background technology]

[0003] In recent years, information terminal devices such as smartphones and other mobile phones, tablet information terminals, and notebook PCs (personal computers) have become widespread. These information terminal devices often contain personal information, and various authentication technologies have been developed to prevent unauthorized use.

[0004] For example, Patent Document 1 discloses an electronic device that includes a fingerprint sensor in a push button switch section. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] US Patent Application Publication No. 2014 / 0056493 Summary of the Invention [Problem to be solved by the invention]

[0006] When adding authentication functions such as fingerprint authentication to electronic devices that function as mobile information terminals, it is necessary to mount a module for capturing images of fingerprints, etc. This increases the number of components and increases the cost of the electronic device.

[0007] An object of one embodiment of the present invention is to reduce the cost of an electronic device having an authentication function. Another object is to reduce the number of components in an electronic device. Another object is to provide a display device that can capture an image of a fingerprint, a vein shape, or the like. Another object is to provide a display device that combines a touch detection function and a function of capturing an image of a fingerprint or a vein shape. Another object is to provide an electronic device that has a biometric authentication function such as a fingerprint authentication function and has a high screen occupancy rate. Another object is to provide a display device that can emit both visible light and infrared light. Another object is to provide an imaging device that can capture an image using both visible light and infrared light as a light source.

[0008] An object of one embodiment of the present invention is to provide a display device, an imaging device, an electronic device, or the like having a novel structure. An object of one embodiment of the present invention is to alleviate at least one of the problems of the prior art.

[0009] Note that the description of these problems does not preclude the existence of other problems. Note that one embodiment of the present invention does not necessarily solve all of these problems. Note that problems other than these can be extracted from the description of the specification, drawings, claims, etc. [Means for solving the problem]

[0010] One embodiment of the present invention is a display device including a first light-emitting element, a second light-emitting element, a light-receiving element, and a light-shielding layer. The first light-emitting element and the light-receiving element are arranged side by side on the same plane. The light-shielding layer is provided above the first light-emitting element and the light-receiving element. The second light-emitting element is provided above the light-shielding layer. The first light-emitting element has a function of emitting visible light upward. The second light-emitting element has a function of emitting invisible light upward. The light-receiving element is a photoelectric conversion element sensitive to visible light and invisible light. In addition, in a plan view, the light-shielding layer has a portion located between the first light-emitting element and the light-receiving element, and in a plan view, the second light-emitting element overlaps with the light-shielding layer and is located inside the outline of the light-shielding layer.

[0011] Another embodiment of the present invention is a display device including a first substrate, a second substrate, a first light-emitting element, a second light-emitting element, a light-receiving element, a light-shielding layer, a first resin layer, and a second resin layer. The first light-emitting element and the light-receiving element are arranged side by side on the first substrate. The first resin layer is provided on the first light-emitting element and the light-receiving element. The light-shielding layer is provided on the first resin layer. The second resin layer is provided on the light-shielding layer. The second light-emitting element is provided on the second resin layer. The second substrate is provided on the second light-emitting element. The first light-emitting element has a function of emitting visible light upward. The second light-emitting element has a function of emitting invisible light upward. The light-receiving element is a photoelectric conversion element sensitive to visible light and invisible light. In addition, in a plan view, the light-shielding layer has a portion located between the first light-emitting element and the light-receiving element. In addition, in plan view, the second light emitting element overlaps the light blocking layer and is located inside the outline of the light blocking layer.

[0012] In the above, the invisible light is preferably light having an intensity in a wavelength range of 750 nm or more and 900 nm or less.

[0013] In any of the above, it is preferable to have a first protective layer. In this case, it is preferable that the first protective layer contains an inorganic insulating material and is located between the first light-emitting element and the light-receiving element and the first resin layer. Furthermore, it is preferable that the first resin layer is provided along the upper surface of the first protective layer.

[0014] In any of the above, it is preferable to have a second protective layer. In this case, it is preferable that the second protective layer contains an inorganic insulating material and is located between the second resin layer and the second light-emitting element. Furthermore, it is preferable that the light-shielding layer is provided along the lower surface of the second resin layer.

[0015] In any of the above, it is preferable that the first resin layer exhibits a first refractive index for light with a wavelength of 850 nm, and the second resin layer exhibits a second refractive index for light with a wavelength of 850 nm. Furthermore, it is preferable that the difference between the first refractive index and the second refractive index is 10% or less of the first refractive index.

[0016] In any of the above, the first light-emitting element preferably has a first pixel electrode, a first light-emitting layer, and a first electrode. The light-receiving element preferably has a second pixel electrode, an active layer, and a first electrode. The first light-emitting layer and the active layer preferably contain different organic compounds. The first electrode preferably has a portion that overlaps with the first pixel electrode via the first light-emitting layer and a portion that overlaps with the second pixel electrode via the active layer. The first pixel electrode and the second pixel electrode preferably contain the same conductive material.

[0017] In any of the above, the second light-emitting element preferably has, from the second substrate side, a third pixel electrode, a second light-emitting layer, and a second electrode. In this case, the third pixel electrode preferably has transparency to invisible light. Also, the second electrode preferably has reflectivity to invisible light. Furthermore, in a plan view, the second electrode is preferably located inside the outline of the light-shielding layer.

[0018] Alternatively, the second electrode is preferably transparent to visible light and invisible light. In this case, the second electrode preferably has a portion overlapping with the light-shielding layer, a portion overlapping with the first light-emitting element, and a portion overlapping with the light-receiving element in a plan view.

[0019] Alternatively, in any of the above, it is preferable that a reflective layer is provided. In this case, it is preferable that the second light-emitting element has, from the second substrate side, a third pixel electrode, a second light-emitting layer, and a second electrode. It is also preferable that the third pixel electrode and the second electrode are transparent to invisible light. It is also preferable that the reflective layer is reflective to invisible light and is located between the light-shielding layer and the second electrode. Furthermore, it is preferable that the reflective layer is located inside the outline of the light-shielding layer in a plan view.

[0020] Another embodiment of the present invention is a display module including any one of the display devices described above and a connector or an integrated circuit.

[0021] Another embodiment of the present invention is an electronic device including the display module and at least one of an antenna, a battery, a housing, a camera, a speaker, a microphone, a touch sensor, and an operation button. The electronic device preferably has a first imaging function in which a first reflected light is received by a light-receiving element when a first light-emitting element emits visible light, and a second imaging function in which a second reflected light is received by a light-receiving element when a second light-emitting element emits invisible light. [Effects of the Invention]

[0022] According to one embodiment of the present invention, it is possible to reduce the cost of an electronic device having an authentication function. Or it is possible to reduce the number of components of an electronic device. Or it is possible to provide a display device capable of capturing an image of a fingerprint, vein pattern, or the like. Or it is possible to provide a display device having both a touch detection function and a fingerprint or vein pattern capturing function. Or it is possible to provide an electronic device having a biometric authentication function such as fingerprint authentication and a high screen occupancy rate. Or it is possible to provide a display device or the like capable of emitting both visible light and infrared light. Or it is possible to provide an imaging device or the like capable of capturing an image using both visible light and infrared light as a light source.

[0023] According to one aspect of the present invention, it is possible to provide a display device, an imaging device, an electronic device, etc. having a novel configuration. According to one aspect of the present invention, it is possible to at least alleviate at least one of the problems of the prior art.

[0024] Note that the description of these effects does not preclude the existence of other effects. Note that one embodiment of the present invention does not necessarily have all of these effects. Note that effects other than these can be extracted from the description in the specification, drawings, claims, etc. [Brief explanation of the drawings]

[0025] [Figure 1] 1A to 1C are diagrams showing configuration examples of a display device. [Figure 2] 2A and 2B are diagrams showing configuration examples of a display device. [Figure 3] 3A and 3B are diagrams showing configuration examples of a display device. [Figure 4] 4A to 4C are diagrams showing configuration examples of a display device. [Figure 5] 5A to 5C are diagrams showing configuration examples of a display device. [Figure 6] 6A to 6D are diagrams showing configuration examples of a display device. [Figure 7] 7A and 7B are diagrams showing configuration examples of a display device. [Figure 8]8A to 8G are diagrams showing configuration examples of the display device. [Figure 9] FIG. 9 is a diagram illustrating an example of the configuration of a display device. [Figure 10] Fig. 10A is a diagram showing a configuration example of a display device, and Fig. 10B is a diagram showing a configuration example of a transistor. [Figure 11] 11A to 11C are diagrams showing configuration examples of electronic devices. [Figure 12] FIG. 12 is a diagram illustrating an example of the configuration of an electronic device. [Figure 13] FIG. 13 is a diagram illustrating an example of the configuration of an electronic device. [Figure 14] FIG. 14 is a diagram illustrating an example of a system configuration. [Figure 15] FIG. 15 is a flow chart illustrating how the system operates. [Figure 16] 16A and 16B are diagrams showing configuration examples of pixel circuits. [Figure 17] 17A and 17B are diagrams showing configuration examples of electronic devices. [Figure 18] 18A to 18D are diagrams showing configuration examples of electronic devices. [Figure 19] 19A to 19F are diagrams showing configuration examples of electronic devices. [Figure 20] FIG. 20 shows the measurement results of the external quantum efficiency of the light-receiving element. [Figure 21] Fig. 21A is a schematic diagram of a light-emitting device, and Fig. 21B shows the measurement results of the light emission intensity of the light-emitting device. [Figure 22] 22A and 22B show the results of measuring the external quantum efficiency-current density characteristics of the light-emitting device, respectively. [Figure 23] Figures 23A and 23D are schematic diagrams showing the imaging method, and Figures 23B, 23C, and 23E show the imaging results. DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, embodiments will be described with reference to the drawings. However, it will be readily understood by those skilled in the art that the embodiments can be implemented in many different ways and that various changes in form and details can be made without departing from the spirit and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the following description of the embodiments.

[0027] In the configuration of the invention described below, the same parts or parts having similar functions are denoted by the same reference numerals in different drawings, and repeated explanations thereof will be omitted. In addition, when referring to similar functions, the same hatch pattern may be used and no particular reference numeral may be assigned.

[0028] In the drawings described in this specification, the size of each component, the thickness of a layer, or an area may be exaggerated for clarity, and therefore, the drawings are not necessarily limited to the scale.

[0029] In this specification, ordinal numbers such as "first" and "second" are used to avoid confusion of components and do not limit the number.

[0030] In the following, expressions indicating directions such as "up" and "down" will basically be used in accordance with the directions in the drawings. However, for purposes such as facilitating explanation, the directions indicated by "up" or "down" in the specification may not match those in the drawings. For example, when explaining the stacking order (or formation order) of a laminate, etc., even if the surface on which the laminate is provided in the drawing (such as the surface to be formed, the supporting surface, the adhesive surface, or the flat surface) is located above the laminate, the direction toward that surface may be expressed as "down" and the opposite direction as "up."

[0031] In this specification and the like, a display panel, which is one aspect of a display device, has a function of displaying (outputting) an image or the like on a display surface, and therefore the display panel is one aspect of an output device.

[0032] In addition, in this specification, a display panel having a connector such as an FPC (Flexible Printed Circuit) or TCP (Tape Carrier Package) attached to the substrate, or having an IC mounted on the substrate using a COG (Chip On Glass) method or the like, may be referred to as a display panel module, display module, or simply a display panel.

[0033] In this specification and the like, a touch panel, which is one aspect of a display device, has a function of displaying an image or the like on a display surface and a function as a touch sensor that detects that a detectable object such as a finger or a stylus touches, presses, or approaches the display surface. Thus, the touch panel is one aspect of an input / output device.

[0034] A touch panel can also be called, for example, a display panel (or display device) with a touch sensor or a display panel (or display device) with a touch sensor function. A touch panel can have a configuration including a display panel and a touch sensor panel. Alternatively, the touch panel can have a touch sensor function inside or on the surface of the display panel.

[0035] In addition, in this specification and the like, a touch panel substrate on which a connector or an IC is mounted may be called a touch panel module, a display module, or simply a touch panel.

[0036] (Embodiment 1) In this embodiment, a display device according to one embodiment of the present invention will be described.

[0037] A display device according to one embodiment of the present invention includes a first light-emitting element that emits visible light, a second light-emitting element that emits invisible light, and a light-receiving element that is sensitive to both invisible light and visible light. The first light-emitting element functions as a display element for displaying an image using visible light. The light-receiving element is preferably a photoelectric conversion element.

[0038] The first light emitting element and the light receiving element are preferably arranged side by side on the same plane, and the second light emitting element is preferably provided on a different plane from the first light emitting element and the light receiving element.

[0039] As the first light-emitting element and the second light-emitting element, it is preferable to use an EL element such as an OLED (Organic Light Emitting Diode) or a QLED (Quantum-dot Light Emitting Diode). Examples of light-emitting materials that the EL element has include fluorescent materials, phosphorescent materials, inorganic compounds (such as quantum dot materials), and materials that exhibit thermally activated delayed fluorescence (thermally activated delayed fluorescence: TADF materials). Alternatively, LEDs such as micro LEDs (Light Emitting Diodes) can be used as the light-emitting elements.

[0040] As the light receiving element, for example, a pn-type or pin-type photodiode can be used. The light receiving element functions as a photoelectric conversion element that detects light incident on the light receiving element and generates an electric charge. The amount of electric charge generated by the photoelectric conversion element is determined according to the amount of incident light. In particular, it is preferable to use an organic photodiode having a layer containing an organic compound as the light receiving element. Organic photodiodes can be easily made thin, lightweight, and large in area, and have a high degree of freedom in shape and design, so they can be applied to various display devices.

[0041] The first light-emitting element and the second light-emitting element may have a laminated structure including a light-emitting layer between a pair of electrodes. The light-receiving element may have a laminated structure including an active layer between a pair of electrodes. The active layer of the light-receiving element may be made of a semiconductor material. For example, an inorganic semiconductor material such as silicon may be used.

[0042] In particular, it is preferable to use an OLED as the first light-emitting element and the second light-emitting element, and an organic photodiode (OPD) as the light-receiving element. This allows the production facilities, manufacturing equipment, and materials used for manufacturing the first light-emitting element, the second light-emitting element, and the light-receiving element to be partially common, thereby reducing manufacturing costs. Furthermore, the manufacturing process can be simplified, thereby improving manufacturing yield.

[0043] Furthermore, when an organic compound is used for the active layer of the light-receiving element, it is preferable that one electrode of the first light-emitting element and one electrode of the light-receiving element (each also referred to as a pixel electrode) are provided on the same surface. Furthermore, it is more preferable that the other electrode of the first light-emitting element and the other electrode of the light-receiving element are electrodes (also referred to as a common electrode) formed from a single continuous conductive layer. Furthermore, it is more preferable that the first light-emitting element and the light-receiving element have a common layer. This can simplify the manufacturing process when manufacturing the first light-emitting element and the light-receiving element, reduce manufacturing costs, and improve manufacturing yields.

[0044] By separately fabricating the light-emitting layer of the first light-emitting element and the active layer of the light-receiving element, the first light-emitting element and the light-receiving element can be fabricated on the same surface. For example, the light-emitting layer and the active layer can be formed in an island or strip shape by a film formation method using a shielding mask such as a metal mask. In a film formation method using a shielding mask, a margin (also called a margin or allowance portion) may be provided between two island-shaped patterns formed using different shielding masks to take into account the spread of the film to be formed.

[0045] In addition, a light-shielding layer that blocks light of the wavelength received by the light-receiving element can be provided in this margin. The light-shielding layer can have an opening or a slit that defines the light-emitting region of the first light-emitting element and the light-receiving region of the light-receiving element.

[0046] The margin is an area that does not contribute to light emission or light reception, and therefore leads to a decrease in the ratio of the light-emitting area or light-receiving area to the area of ​​the display unit of the display device (effective light-emitting area ratio or effective light-receiving area ratio).

[0047] Therefore, in one embodiment of the present invention, a second light-emitting element that emits invisible light is provided in a portion corresponding to the margin. The invisible light can be used as a light source when an object is captured by a light-receiving element. Furthermore, the second light-emitting element is preferably disposed above (on the display surface side of) the light-shielding layer. Furthermore, the second light-emitting element is preferably disposed so as to overlap with the light-shielding layer and be located inside the outline of the light-shielding layer in a plan view. That is, the second light-emitting element is preferably disposed so that the edge of the light-emitting region of the second light-emitting element is located inside the edge of the light-shielding layer. This allows part of the invisible light emitted by the second light-emitting element to be blocked by the light-shielding layer, preventing it from directly entering the light-receiving element. This enables the display device to capture clear images with reduced noise.

[0048] Examples of invisible light include infrared light and ultraviolet light. In particular, infrared light having one or more peaks in the wavelength range of 700 nm to 2500 nm can be preferably used. In particular, light having an intensity in the wavelength range of 750 nm to 1000 nm, preferably light having one or more peaks in this wavelength range, is preferred because it broadens the range of materials to be used for the active layer of the light-receiving element.

[0049] By using the above-described infrared light as invisible light, the display device can also capture images of blood vessels, particularly veins, of fingers or hands using a light-receiving element. For example, light with a wavelength of 760 nm or thereabouts is not absorbed by reduced hemoglobin in veins. Therefore, the positions of veins can be detected by receiving reflected light from the palm or fingers using a light-receiving element and converting it into an image. A module or electronic device including the display device of one embodiment of the present invention can perform vein authentication, which is one type of biometric authentication, by using the captured image of veins.

[0050] Furthermore, by using visible light emitted by the first light-emitting element as a light source, it is possible to capture images of palm prints on a palm or fingerprints on a fingertip. Furthermore, because part of infrared light is also reflected by the surface of the skin, infrared light emitted by the second light-emitting element can also be used to capture images of fingerprints. A module or electronic device including the display device of one embodiment of the present invention can perform fingerprint authentication, which is one type of biometric authentication, by using a captured image of a fingerprint.

[0051] A more specific configuration example will be described below with reference to the drawings.

[0052] [Display device configuration example 1] 1A shows an example of the configuration of a display device 10. Between a substrate 11 and a substrate 12, the display device 10 has a light-emitting element 21R, a light-emitting element 21G, a light-emitting element 21B, a light-receiving element 22, a light-emitting element 23IR, a light-shielding layer 24, and the like.

[0053] The light-emitting elements 21R, 21G, 21B, and the light-receiving element 22 are arranged side by side on the substrate 11. The light-shielding layer 24 is provided above the light-emitting elements 21R, 21G, and 21B with an insulating layer 31 interposed therebetween. The light-emitting element 23IR is arranged on the light-shielding layer 24 with an insulating layer 32 interposed therebetween. The light-shielding layer 24 has, in a planar view, portions positioned between the light-emitting elements and portions positioned between any of the light-emitting elements and the light-receiving element 22. Similarly, the light-emitting element 23IR also has, in a planar view, portions positioned between the light-emitting elements and portions positioned between any of the light-emitting elements and the light-receiving element 22.

[0054] The light emitting elements 21R, 21B, and 21G emit red (R), blue (B), and green (G) light, respectively.

[0055] The display device 10 has a plurality of pixels arranged in a matrix. Each pixel has one or more sub-pixels. Each sub-pixel has one light-emitting element. For example, a pixel may have three sub-pixels (e.g., three colors of R, G, and B, or three colors of yellow (Y), cyan (C), and magenta (M)), or four sub-pixels (e.g., four colors of R, G, B, and white (W), or four colors of R, G, B, and Y). Each pixel also has a light-receiving element 22. The light-receiving element 22 may be provided in all pixels or in some of the pixels. Alternatively, one pixel may have multiple light-receiving elements 22.

[0056] A margin necessary for fabricating the light-emitting element and the light-receiving element 22 separately is provided between two adjacent light-emitting elements and between the light-emitting element and the light-receiving element 22. In FIG. 1A, the light-emitting element 21R and the light-emitting element 21B are spaced apart by a distance M. For example, when forming island-shaped organic films as films constituting the light-emitting element or the light-receiving element by vacuum deposition using a metal mask, deviations from the design in the shape and position of the island-shaped organic films may occur due to factors such as the accuracy of alignment between the metal mask and the substrate, deflection of the metal mask, and vapor scattering. Therefore, it is preferable that the distance M between adjacent elements be 10 μm or more, preferably 20 μm or more, or even 30 μm or more, and 200 μm or less, preferably 100 μm or less.

[0057] In this specification, the term "light-emitting element" may refer to a light-emitting region. As a specific example, when a light-emitting element has a pair of electrodes and a light-emitting layer therebetween, the region where these are stacked and which emits light when an electric field is applied may be referred to as the light-emitting element (light-emitting region). Therefore, some or all of the components of the light-emitting element may be located in a region different from the light-emitting region. Similarly, the term "light-receiving element" may refer to a light-receiving region.

[0058] The light emitting element 23IR emits invisible light. Here, an example is shown in which the light emitting element 23IR emits infrared light IR.

[0059] The light receiving element 22 is a photoelectric conversion element that is sensitive to at least the infrared light emitted by the light emitting element 23IR. The light receiving element 22 may be sensitive to, for example, a wavelength range of 700 nm to 900 nm.

[0060] Furthermore, it is preferable that the light receiving element 22 is sensitive not only to infrared light but also to the light emitted by each of the light emitting elements 21R, 21B, and 21G. When the light receiving element 22 is sensitive to visible light and infrared light, it is preferable that the light receiving element 22 is sensitive to, for example, a wavelength range of 500 nm to 1000 nm, a wavelength range of 500 nm to 950 nm, or a wavelength range of 500 nm to 900 nm.

[0061] 1A shows a state in which a finger 60 is touching the surface of the substrate 12. At this time, part of the infrared light IR emitted from the light-emitting element 23IR is reflected by the surface or inside of the finger 60, and part of the reflected light is incident on the light-receiving element 22. This makes it possible to obtain information about the position where the finger 60 is touching. In addition, it is possible to capture an image of one or both of the vein shape and fingerprint shape of the finger 60.

[0062] Furthermore, the position information of the finger 60 or the image of the fingerprint can be acquired by the light emitted from any one of the light-emitting elements 21R, 21B, and 21G. In Fig. 1B, as an example, the state in which the light G emitted from the light-emitting element 21G is reflected from the finger 60 and received by the light-receiving element 22 is shown.

[0063] 1C, even if the finger 60 is separated from the substrate 12, the position information of the finger 60 can be acquired. That is, the display device 10 can function as a non-contact touch panel. Depending on the distance between the finger 60 and the substrate 12, it may be possible to acquire the shape of a fingerprint or veins. In this case, a module or electronic device to which the display device 10 is applied can function as a non-contact biometric authentication device.

[0064] The smaller the arrangement interval of the light receiving elements 22, the higher the resolution of the captured image. For example, by setting the arrangement interval of the light receiving elements 22 to be smaller than the distance between two convex portions of a fingerprint, preferably the distance between adjacent concave and convex portions, a clearer fingerprint image can be obtained. Since the distance between concave and convex portions of a human fingerprint is approximately 200 μm, for example, the arrangement interval of the light receiving elements 22 is 400 μm or less, preferably 200 μm or less, more preferably 150 μm or less, even more preferably 100 μm or less, and even more preferably 50 μm or less, and is 1 μm or more, preferably 10 μm or more, and more preferably 20 μm or more.

[0065] The display device 10 can capture images of not only fingerprints but also various objects that come into contact with or approach the surface of the substrate 12. Therefore, the display device 10 can also be used as an image sensor panel. For example, a color image can be obtained by sequentially activating the light-emitting element 21R, the light-emitting element 21B, and the light-emitting element 21G, capturing an image each time using the light-receiving element 22, and combining the three images obtained. In other words, an electronic device to which the display device 10 is applied can also be used as an image scanner capable of capturing color images. Furthermore, the display device 10 can be used as an image scanner using infrared light by capturing an image using the light-receiving element 22 while the light-emitting element 23IR is emitting light.

[0066] Furthermore, the display device 10 can also function as a touch panel or a pen tablet using the light receiving element 22. Unlike the case where a capacitance type touch sensor or an electromagnetic induction type touch sensor is used, the use of the light receiving element 22 makes it possible to detect the position of even a highly insulating object to be detected, so that the material of the object to be detected, such as a stylus, can be any material, and various writing implements (for example, a brush, a glass pen, a feather pen, etc.) can also be used.

[0067] [Display device configuration example 2] A more specific example of the configuration of the display device will be described below.

[0068] Fig. 2A shows a schematic top view of the display device 100 exemplified below as viewed from the display surface side, and Fig. 2B shows a schematic cross-sectional view corresponding to the cut surface taken along dashed line X1-X2 in Fig. 2A.

[0069] The display device 100 has a light receiving element 110, a light emitting element 190, a light emitting element 160, a transistor 131, a transistor 132, a light blocking layer 145, a resin layer 141, and a resin layer 142 between a pair of substrates (substrate 151 and substrate 152).

[0070] The light emitting element 190 emits light of any one of red (R), green (G), and blue (B).

[0071] 2A shows the top shapes of the light receiving element 110, the light emitting element 190, the light emitting element 160, and the light blocking layer 145. The light emitting element 190 is distinguished by assigning the symbols R, G, and B according to the emitted light color. The light receiving element 110 is assigned the symbol PD.

[0072] 2A, rows in which R light-emitting elements 190 and G light-emitting elements 190 are alternately arranged and rows in which light-receiving elements 110 and B light-emitting elements 190 are alternately arranged in the column direction. Note that the relative positional relationship between each light-emitting element 190 and light-receiving element 110 is not limited to this, and any two elements may be interchanged.

[0073] A light-shielding layer 145 is provided between two adjacent light-emitting elements 190 and between adjacent light-receiving elements 110 and light-emitting elements 190. A light-emitting element 160 is disposed on the light-shielding layer 145. In FIG. 2A , a lattice-shaped light-emitting element 160 is provided on a lattice-shaped light-shielding layer 145. As shown in FIG. 2A , the light-emitting element 160 is preferably provided inside the outline of the light-shielding layer 145. In other words, in a plan view, it is preferable that an end of the light-shielding layer 145 is located between the light-receiving element 110 and the light-emitting element 160. It is also preferable that another end of the light-shielding layer 145 is located between the light-emitting element 190 and the light-emitting element 160 in a plan view.

[0074] 2A shows an example in which the light-emitting element 160 is continuous across the entire display area. With this configuration, the entire display area can be set to an emitting or non-emitting state, which greatly simplifies the control of driving the light-emitting element 160.

[0075] 3A shows an example in which strip-shaped light emitting elements 160 that are long in the row direction are arranged in the column direction. With this configuration, the strip-shaped light emitting elements 160 can be made to emit light in sequence.

[0076] 3B shows an example in which island-shaped light-emitting elements 160 are arranged in a matrix. In this case, a passive matrix driving method can be applied to the light-emitting elements 160. Alternatively, an active matrix driving method can also be applied.

[0077] In FIG. 3B, for ease of understanding, the top surface shape and size of the light-emitting element 160 are shown to be the same as those of the light-emitting element 190 and the light-receiving element 110, but this is not limited to this, and the top surface shapes and sizes of the light-emitting element 160, each light-emitting element 190, and the light-receiving element 110 may be different.

[0078] As shown in FIG. 2B, the transistor 131 and the transistor 132 are provided on the substrate 151, and an insulating layer 214 is provided thereon.

[0079] The light receiving element 110 has a pixel electrode 111, a photoelectric conversion layer 112, and a common electrode 113. The light emitting element 190 has a pixel electrode 191, an EL layer 192, and a common electrode 113. The photoelectric conversion layer 112 has at least an active layer. The EL layer 192 has at least a light emitting layer.

[0080] The light-emitting element 190 has a function of emitting visible light. Specifically, the light-emitting element 190 is an electroluminescent element that emits light 121 toward the substrate 152 by applying a voltage between the pixel electrode 191 and the common electrode 113.

[0081] The light receiving element 110 has a function of detecting light. Specifically, the light receiving element 110 is a photoelectric conversion element that receives light 122 incident from the outside through the substrate 152 and converts the light into an electrical signal.

[0082] The pixel electrode 111 and the pixel electrode 191 are provided on the same surface. The pixel electrode 111 and the pixel electrode 191 are preferably formed by processing the same conductive film. The pixel electrode 111 and the pixel electrode 191 preferably have a function of reflecting visible light and infrared light. Ends of the pixel electrode 111 and the pixel electrode 191 are covered with a partition wall 216. The common electrode 113 has a function of transmitting visible light and infrared light.

[0083] The common electrode 113 is provided in common to the light receiving element 110 and the light emitting element 190. Specifically, the common electrode 113 has a portion overlapping with the pixel electrode 111 via the photoelectric conversion layer 112, and a region overlapping with the pixel electrode 191 via the EL layer 192.

[0084] The light receiving element 110 and the light emitting element 190 may have a common layer other than the common electrode 113. For example, an active layer and a light emitting layer may be separately formed, and all other layers may be used in common.

[0085] Layers commonly used in the light-receiving element 110 and the light-emitting element 190 may have different functions in the light-emitting element and the light-receiving element. In this specification, components are named based on their functions in the light-emitting element. For example, a hole injection layer functions as a hole injection layer in the light-emitting element and as a hole transport layer in the light-receiving element. Similarly, an electron injection layer functions as an electron injection layer in the light-emitting element and as an electron transport layer in the light-receiving element. Furthermore, a hole transport layer functions as a hole transport layer in both the light-emitting element and the light-receiving element. Similarly, an electron transport layer functions as an electron transport layer in both the light-emitting element and the light-receiving element.

[0086] A protective layer 195 is provided on the common electrode 113 to cover the light receiving element 110 and the light emitting element 190. The protective layer 195 has a function of preventing impurities such as water from diffusing from the resin layer 141 side to the light receiving element 110 and the light emitting element 190. Furthermore, by providing the protective layer 195, damage to the light receiving element 110 and the light emitting element 190 during the process after the process of forming the protective layer 195 can be reduced.

[0087] The protective layer 195 may have a single layer structure or a multilayer structure including at least an inorganic insulating film. Examples of the inorganic insulating film include oxide films or nitride films such as a silicon oxide film, a silicon oxynitride film, a silicon nitride oxide film, a silicon nitride film, an aluminum oxide film, an aluminum oxynitride film, and a hafnium oxide film.

[0088] A resin layer 141 is provided to cover the protective layer 195. The resin layer 141 functions as a planarizing film.

[0089] A light-shielding layer 145 is provided on the resin layer 141. The light-shielding layer 145 preferably absorbs visible light and infrared light. For example, a black matrix can be formed as the light-shielding layer 145 using a metal material or a resin material containing a pigment (carbon black, etc.) or a dye. The light-shielding layer 145 may have a layered structure in which two or more of a red color filter, a green color filter, and a blue color filter are layered.

[0090] A light emitting element 160 is provided at a position overlapping the light blocking layer 145. The light emitting element 160 is formed on the substrate 152 side. The light emitting element 160 has an electrode 161, an EL layer 162, and an electrode 163 from the substrate 152 side.

[0091] The light-emitting element 160 has a function of emitting infrared light. Specifically, the light-emitting element 160 is an electroluminescent element that emits light 123 toward the substrate 152 side by applying a voltage between an electrode 161 and an electrode 163.

[0092] The insulating layer 217 is provided to cover an edge of the electrode 161. The insulating layer 217 preferably functions as a planarization film.

[0093] 2B shows an example in which electrode 161, EL layer 162, and electrode 163 are each processed to be located inside the outline of light-shielding layer 145 in a plan view. In this case, as shown in FIG. 2B, it is preferable that electrode 163 covers the end of EL layer 162. This allows electrode 163 to function as a protective layer, preventing impurities such as water from diffusing from the resin layer 142 side to EL layer 162, thereby improving the reliability of light-emitting element 160.

[0094] The electrode 163 preferably has a function of reflecting infrared light, and the electrode 161 preferably has a function of transmitting infrared light.

[0095] 2B, it is preferable to configure the display device such that the EL layer 162 and the electrode 163 are not provided above the light emitting element 190 and above the light receiving element 110. This prevents a portion of the light 121 and the light 122 from being reflected or absorbed by the EL layer 162 and the electrode 163, and thus makes it possible to realize a display device with high light emitting efficiency and light receiving sensitivity.

[0096] A resin layer 142 is provided to cover the light emitting element 160. A part of the resin layer 142 is provided in contact with the light blocking layer 145 and the resin layer 141. The resin layer 142 preferably functions as an adhesive layer for bonding the substrate 152 to the substrate 151.

[0097] Here, resin layer 141 and resin layer 142 are located on the optical path of light 121 emitted by light emitting element 190. When resin layer 141 and resin layer 142 are in contact with each other, the smaller the difference in their refractive indexes, the smaller the influence of refraction and reflection at their interface, thereby increasing the light extraction efficiency of light emitting element 190. Furthermore, it is possible to prevent light 121 from being reflected at the interface between resin layer 141 and resin layer 142 and a portion of the light from being directly incident on light receiving element 110. Therefore, it is preferable that the difference in the refractive indexes of resin layer 141 and resin layer 142 relative to the peak wavelength of light 121 emitted by light emitting element 190 is 10% or less of the refractive index of resin layer 141. In particular, it is preferable that resin layer 141 and resin layer 142 are made of the same material.

[0098] Similarly, resin layers 141 and 142 are also located on the optical path of light 122 reaching light receiving element 110. By reducing the difference in refractive index between these layers, it is possible to increase the amount of light 122 reaching light receiving element 110. For this reason, it is preferable that the difference in refractive index between resin layers 141 and 142 with respect to the peak wavelength of light 121 emitted by light emitting element 160 is 10% or less of the refractive index of resin layer 141. In particular, it is preferable that the difference in refractive index between resin layers 141 and 142 with respect to light with a wavelength of 850 nm is 10% or less of the refractive index of resin layer 141.

[0099] The transistors 131 and 132 are in contact with the top surface of the same layer (the substrate 151 in FIG. 2B ). The pixel electrode 111 is electrically connected to the source or drain of the transistor 131 through an opening provided in the insulating layer 214. The pixel electrode 191 is electrically connected to the source or drain of the transistor 132 through an opening provided in the insulating layer 214. The transistor 132 has a function of controlling driving of the light-emitting element 190.

[0100] At least a part of the circuit electrically connected to the light receiving element 110 is preferably formed using the same material and in the same process as the circuit electrically connected to the light emitting element 190. This allows the display device to be thinner and the manufacturing process to be simplified compared to when the two circuits are formed separately.

[0101] Here, the common electrode 113 provided in common to the light emitting element 190 and the light receiving element 110 is preferably electrically connected to a wiring to which a first potential is applied. As the first potential, a fixed potential such as a common potential, a ground potential, or a reference potential can be used. Note that the first potential applied to the common electrode 113 is not limited to a fixed potential, and two or more different potentials can be selected and applied.

[0102] When the light receiving element 110 receives light and converts it into an electrical signal, it is preferable to apply a second potential to the pixel electrode 111 that is lower than the first potential applied to the common electrode 113. The second potential can be selected to optimize the light receiving sensitivity, etc., depending on the configuration, optical characteristics, and electrical characteristics of the light receiving element 110. That is, when the light receiving element 110 is considered as a photodiode, the first potential applied to the common electrode 113, which functions as a cathode, and the second potential applied to the pixel electrode 111, which functions as an anode, can be selected so that a reverse bias voltage is applied. Note that when the light receiving element 110 is not driven, the pixel electrode 111 may be applied with a potential that is the same as or approximately the same as the first potential, or a potential higher than the first potential.

[0103] On the other hand, when the light-emitting element 190 is caused to emit light, it is preferable to apply a third potential higher than the first potential applied to the common electrode 113 to the pixel electrode 191. The third potential can be selected and applied so as to achieve the required light emission luminance depending on the configuration, threshold voltage, current-luminance characteristics, etc. of the light-emitting element 190. That is, when the light-emitting element 190 is considered as a light-emitting diode, the first potential applied to the common electrode 113 functioning as a cathode and the third potential applied to the pixel electrode 191 functioning as an anode can be selected so that a forward bias voltage is applied. Note that when the light-emitting element 190 is not caused to emit light, the pixel electrode 191 may be applied with a potential that is the same as or approximately the same as the first potential, or a potential lower than the first potential.

[0104] Although the example in which the common electrode 113 functions as a cathode and each pixel electrode functions as an anode for the light receiving element 110 and the light emitting element 190 has been described here, the present invention is not limited thereto, and the common electrode 113 may function as an anode and each pixel electrode may function as a cathode. In that case, a potential higher than the first potential may be applied as the second potential when driving the light receiving element 110, and a potential lower than the first potential may be applied as the third potential when driving the light emitting element 190.

[0105] [Configuration Example 2-2] 4A shows a schematic cross-sectional view of a display device that is partially different in configuration from the display device 100 described above. The display device 100A shown in FIG. 4A differs from the display device 100 described above mainly in that the configuration of the light-emitting element 160 is different.

[0106] The light-shielding layer 145 is formed along the lower surface of the resin layer 142. In other words, the lower surface of the resin layer 142 forms the surface on which the light-shielding layer 145 is formed. Note that a different layer may be provided between the resin layer 142 and the light-shielding layer 145, and in that case, the resin layer 142 and the light-shielding layer 145 do not come into contact with each other.

[0107] In addition, a protective layer 169 is provided to cover the light-emitting element 160. The protective layer 169 can be made of the same material as the protective layer 195. In the manufacturing process of the display device 100A, the light-shielding layer 145 is formed after the light-emitting element 160 is formed. Therefore, by providing the protective layer 169 to cover the light-emitting element 160, damage to the light-emitting element 160 during the process of forming the light-shielding layer 145 can be suppressed.

[0108] In FIG. 4A, the protective layer 195 may not be provided if it is not necessary.

[0109] [Configuration Example 2-3] FIG. 4B shows a schematic cross-sectional view of a display device 100B having a different configuration from the above.

[0110] The electrode 163t of the light-emitting element 160 is transparent to visible light and infrared light. Furthermore, the EL layer 162 and the electrode 163t of the light-emitting element 160 each have a portion overlapping with the light-receiving element 110 and a portion overlapping with the light-emitting element 190. With this configuration, the EL layer 162 and the electrode 163t can each be formed as a continuous film, thereby simplifying the process. Furthermore, since the EL layer 162 and the electrode 163t of the light-emitting element 160 can be formed continuously, impurities (such as water) contained in the air can be prevented from entering between them, thereby improving reliability.

[0111] The EL layer 162 and the electrode 163t are preferably made of films that have low absorption of visible light because they transmit visible light emitted by the light-emitting element 190. For example, it is preferable to select the materials and thicknesses of the EL layer 162 and the electrode 163t so that the laminate of the EL layer 162 and the electrode 163t has a transmittance of 50% to 100%, preferably 60% to 100%, and more preferably 70% to 100%, for the light emitted by the light-emitting element 190.

[0112] Furthermore, since the EL layer 162 and the electrode 163t transmit light 122, which is light 123 including infrared light emitted by the light emitting element 160 and reflected by an object, it is preferable to use a film that has low absorption of infrared light. For example, it is preferable to select the materials and thicknesses of the EL layer 162 and the electrode 163t so that the laminate of the EL layer 162 and the electrode 163t has a transmittance of 50% to 100%, preferably 60% to 100%, and more preferably 70% to 100%, for the infrared light emitted by the light emitting element 160.

[0113] By increasing the transmittance of the EL layer 162 and the electrode 163 to visible light and infrared light, the light extraction efficiency is improved, thereby increasing the display brightness or light emission brightness of the display device. Furthermore, the brightness of the light 122 reaching the light receiving element 110 can be increased, thereby increasing the detection sensitivity.

[0114] Furthermore, a reflective layer 168 that is reflective to infrared light is provided between the light-shielding layer 145 and the electrode 163t of the light-emitting element 160. The reflective layer 168 is provided on the light-shielding layer 145. Infrared light emitted from the light-emitting element 160 toward the substrate 151 is reflected by the reflective layer 168 and emitted to the outside via the substrate 152. By providing the reflective layer 168, it is possible to increase the light extraction efficiency of the light-emitting element 160. The reflective layer 168 is provided so as to be located inside the outline of the light-shielding layer 145 in a plan view.

[0115] [Configuration Example 2-4] FIG. 4C shows a schematic cross-sectional view of a display device 100C having a different configuration from the above.

[0116] In the display device 100C, an example is shown in which the reflective layer 168 and the light-shielding layer 145 are formed on the substrate 152 side.

[0117] The reflective layer 168 is provided along the lower surface of the resin layer 142 that covers the light emitting element 160. Furthermore, a resin layer 143 is provided to cover the reflective layer 168 and the resin layer 142. Furthermore, a light-shielding layer 145 is provided along the lower surface of the resin layer 143.

[0118] The resin layer 143 is located on the surface on which the light-shielding layer 145 is to be formed, and functions as a planarizing layer. Note that the light-shielding layer 145 may be provided to cover the lower surface of the reflective layer 168 without providing the resin layer 143.

[0119] Resin layer 143 is located on the optical paths of light 121 and light 122, and is located between resin layer 142 and resin layer 141. For this reason, resin layer 143 is preferably made of a material that has a small difference in refractive index between resin layer 142 and resin layer 141. It is more preferable that resin layer 141, resin layer 142, and resin layer 143 be made of the same material.

[0120] In addition, FIG. 4C shows an example in which the EL layer 162 and the electrode 163t of the light-emitting element 160 are processed so as not to overlap with the light-emitting element 190 and the light-receiving element 110, but they may be formed using a continuous film, as in the display device 100B described above.

[0121] [Display device configuration example 3] An example of a circuit configuration that can be used in a display device will be described below.

[0122] 5A is a schematic perspective view of a display device 50. As shown in FIG. 5A, the display device of one embodiment of the present invention can be understood to have a stacked structure of a layer 51 having a light-emitting element 21 and a light-receiving element 22 and a layer 52 having a light-emitting element 23.

[0123] In the layer 51, the light emitting elements 21 and the light receiving elements 22 are arranged in a matrix.

[0124] The layer 52 is provided with light-emitting elements 23. Here, an example is shown in which the light-emitting elements 23 are arranged in a matrix. However, the arrangement method of the light-emitting elements 23 is not limited to this, and one light-emitting element 23 may be arranged across the entire layer 52, or light-emitting elements 23 having a strip-shaped upper surface may be arranged in one direction.

[0125] Next, a circuit for controlling the light emission and light reception of the display device 50 will be described.

[0126] 5B is a block diagram illustrating an example of the configuration of layer 51 and its peripheral circuits. Layer 51 includes pixels 71 and 72. Pixel 71 functions as a subpixel and is a circuit for controlling the light emission brightness of red, green, or blue light-emitting element 21. Pixel 72 is a circuit for controlling the light receiving and readout operations of light-receiving element 22.

[0127] The pixel 71 has at least a transistor (selection transistor) for controlling selection and non-selection of the pixel, and a transistor (drive transistor) for controlling the current flowing through the light emitting element 21. The pixel 71 can be driven by an active matrix system.

[0128] Furthermore, the pixel 72 has at least a transistor (selection transistor) for controlling selection and non-selection of the pixel. The pixel 72 can be driven by an active matrix method.

[0129] The layer 51 is electrically connected to a circuit unit 75a, a circuit unit 76a, a circuit unit 77, and a circuit unit 78. The circuit unit 75a is electrically connected to a plurality of pixels 71 arranged in the row direction via wiring GLa. The circuit unit 76a is electrically connected to a plurality of pixels 71 arranged in the column direction via wiring SLa. The circuit unit 77 is electrically connected to a plurality of pixels 72 arranged in the row direction via wiring CL. The circuit unit 78 is electrically connected to a plurality of pixels 72 arranged in the column direction via wiring WL. Note that although the wiring GLa, the wiring SLa, the wiring CL, and the wiring WL are each shown as a single wiring, they may each be a plurality of wirings to which different signals or potentials are supplied.

[0130] The circuit portion 75a functions as a scanning line driver circuit (also referred to as a gate line driver circuit, gate driver, scan driver, etc.). The circuit portion 75a has a function of generating a selection signal for selecting the pixel 71 and outputting the selection signal to the wiring GLa. The circuit portion 76a functions as a signal line driver circuit (also referred to as a source line driver circuit, source driver, etc.). The circuit portion 76a has a function of outputting a data signal (data potential) to the wiring SLa.

[0131] The circuit unit 77 functions as a scanning line driving circuit. The circuit unit 77 has a function of generating timing signals to be supplied to the pixels 72 and outputting them to the wiring CL. The circuit unit 78 functions as a readout circuit. The circuit unit 78 has a function of converting signals output from the pixels 72 via the wiring WL into data (digital data or analog data) that can be processed by external equipment and outputting the data.

[0132] 5C is a block diagram illustrating an example of the configuration of the layer 52 and its peripheral circuits. The layer 52 has pixels 73. The pixels 73 are circuits for controlling the luminance of the light-emitting elements 23. The pixels 73 can have the same configuration as the pixels 71. The pixels 73 can be driven by an active matrix system.

[0133] A circuit section 75b and a circuit section 76b are electrically connected to the layer 52. The circuit section 75b is electrically connected to a plurality of pixels 73 arranged in the row direction via wiring GLb. The circuit section 76b is electrically connected to a plurality of pixels 73 arranged in the column direction via wiring SLb.

[0134] The circuit section 75b functions as a scanning line driving circuit, and the circuit section 76b functions as a signal line driving circuit. The explanations of the circuit sections 75a and 76a can be applied to the circuit sections 75b and 76b, respectively.

[0135] The light-emitting elements 23 of the layer 52 may be configured to control light emission by a passive matrix method or a segment method, which simplifies the pixel configuration and the configuration of the peripheral circuitry, thereby reducing manufacturing costs.

[0136] FIG. 6A shows an example in which a passive matrix driving method is applied.

[0137] 6A includes a layer 52a, a circuit section 79a, and a circuit section 79b. A plurality of light-emitting elements 23 are arranged in a matrix on the layer 52a. The circuit section 79a includes wiring SL X The circuit portion 79b is electrically connected to the anodes of the plurality of light emitting elements 23 arranged in the row direction via the wiring SL Y , and are electrically connected to the cathodes of the plurality of light-emitting elements 23 arranged in the column direction.

[0138] The light emitting element 23 is connected to the wiring SL X The anode potential is applied from the circuit portion 79a via the wiring SL Y The cathode can emit light at a brightness according to the potential difference given by the circuit section 79b via the cathode.

[0139] FIG. 6B shows an example in which a segment driving method is applied.

[0140] The display device shown in FIG. 6B has a layer 52b and a circuit section 79c. A plurality of light-emitting elements 23 are arranged in a matrix on the layer 52b. A plurality of wirings AL are electrically connected to the circuit section 79c. An anode of one light-emitting element 23 is electrically connected to each wiring AL. An anode potential is applied to the anode of the light-emitting element 23 from the circuit section 79c via the wiring AL. Furthermore, a cathode of each of the plurality of light-emitting elements 23 is electrically connected to a wiring CL. A cathode potential is applied to the wiring CL.

[0141] In the configuration shown in FIG. 6B, an anode potential can be applied individually to each of the light-emitting elements 23 to cause them to emit light.

[0142] 6C includes a layer 52c having a plurality of light-emitting elements 23 arranged in the column direction, and a circuit section 79c. An anode potential is applied to the anode of the light-emitting element 23 from the circuit section 79c via a wiring AL. A cathode potential is applied to the cathode of the light-emitting element 23 via a wiring CL.

[0143] The display device shown in FIG. 6C can suitably use a configuration in which light emitting elements 23 having a strip-shaped upper surface are arranged in one direction.

[0144] 6D shows an example in which one light-emitting element 23 is provided. One light-emitting element 23 is provided on layer 52d. An anode potential is applied to the anode of the light-emitting element 23 from circuit section 79d via wiring AL, and a cathode potential is applied to the cathode via wiring CL.

[0145] Since the display device shown in Figure 6D is configured to have one light-emitting element 23, the circuit section 79d only needs to control the brightness of the light emitted (i.e., the magnitude of the anode potential) and the timing of light emission, which allows for a simpler circuit configuration than the above.

[0146] 6A to 6D, the light-emitting element 23 shown by one circuit symbol may be composed of multiple light-emitting elements. For example, multiple light-emitting elements connected in series or in parallel can be regarded as one light-emitting element.

[0147] Here, the period during which the light-emitting element 23 emits light may overlap with the period during which an image is captured by the light-receiving element 22. By shortening the period during which the light-emitting element 23 emits light, that is, by making the light-emitting element 23 emit light instantaneously or intermittently rather than continuously, the power consumption of the display device 50 can be reduced. For example, the period during which the light-emitting element 23 emits light at one time may be approximately the same length as the exposure period of the light-receiving element 22. For example, the period during which the light-emitting element 23 emits light at one time may be 10 μs or more and 10 ms or less, preferably 100 μs or more and 5 ms or less.

[0148] Furthermore, when the light emitting element 23 is caused to emit light instantaneously or intermittently, it is preferable to emit light strongly. This shortens the period required for exposure, further shortening the light emitting period of the light emitting element 23 and improving the reliability of the display device. It is preferable that the light emitted by the light emitting element 23 is stronger (light with a high radiant emittance) than when the light emitting element 21 (one of the light emitting element 21R, light emitting element 21G, and light emitting element 21B) is caused to emit light at the highest luminance. For example, the light emitting element 23 has a radiant emittance of 30 mW / m 2 or more, preferably 100mW / m 2 The higher the upper limit of the radiant emittance of the light-emitting element 23, the better. 2 The brightness of the light emitting element 23 may be adjusted appropriately depending on the intensity of external light, the reflectance of the subject, and the like.

[0149] [Device Structure] Next, detailed structures of a light-emitting element, a light-receiving element, and a light-emitting and light-emitting element that can be used in the display device of one embodiment of the present invention will be described.

[0150] The light-emitting element exemplified below can be applied to the light-emitting element 21 exemplified above. The light-receiving element and light-receiving / light-emitting element exemplified below can be applied to the light-receiving element 22 exemplified above. The light-emitting element exemplified below can be applied to the light-emitting element 23 exemplified above.

[0151] The display device of one embodiment of the present invention may be any of a top emission type that emits light in a direction opposite to a substrate on which a light-emitting element is formed, a bottom emission type that emits light toward a substrate on which a light-emitting element is formed, and a dual emission type that emits light to both sides.

[0152] In this embodiment, a top-emission display device will be described as an example.

[0153] In this specification, unless otherwise specified, even when describing a configuration having a plurality of elements (light-emitting elements, light-emitting layers, etc.), when describing matters common to each element, the alphabet will be omitted. For example, when describing matters common to light-emitting layer 283R and light-emitting layer 283G, etc., they may be referred to as light-emitting layer 283.

[0154] A display device 280A shown in FIG. 7A has a light receiving element 270PD, a light emitting element 270R that emits red (R) light, a light emitting element 270G that emits green (G) light, and a light emitting element 270B that emits blue (B) light.

[0155] Each light-emitting element has a pixel electrode 271, a hole injection layer 281, a hole transport layer 282, a light-emitting layer 283, an electron transport layer 284, an electron injection layer 285, and a common electrode 275 stacked in this order. Light-emitting element 270R has a light-emitting layer 283R, light-emitting element 270G has a light-emitting layer 283G, and light-emitting element 270B has a light-emitting layer 283B. Light-emitting layer 283R contains a light-emitting material that emits red light, light-emitting layer 283G contains a light-emitting material that emits green light, and light-emitting layer 283B contains a light-emitting material that emits blue light.

[0156] The light emitting element is an electroluminescent element that emits light toward the common electrode 275 when a voltage is applied between the pixel electrode 271 and the common electrode 275 .

[0157] The light receiving element 270PD has a pixel electrode 271, a hole injection layer 281, a hole transport layer 282, an active layer 273, an electron transport layer 284, an electron injection layer 285, and a common electrode 275 stacked in this order.

[0158] The light receiving element 270PD is a photoelectric conversion element that receives light incident from outside the display device 280A and converts it into an electrical signal.

[0159] In this embodiment, in both the light-emitting element and the light-receiving element, the pixel electrode 271 functions as an anode, and the common electrode 275 functions as a cathode. In other words, by applying a reverse bias between the pixel electrode 271 and the common electrode 275 and driving the light-receiving element, the light incident on the light-receiving element can be detected, an electric charge can be generated, and the electric charge can be extracted as a current.

[0160] In the display device of this embodiment, an organic compound is used for the active layer 273 of the light-receiving element 270PD. The layers of the light-receiving element 270PD other than the active layer 273 can be configured in common with the light-emitting element. Therefore, by simply adding a step of forming the active layer 273 to the manufacturing process of the light-emitting element, the light-receiving element 270PD can be formed in parallel with the formation of the light-emitting element. Furthermore, the light-emitting element and the light-receiving element 270PD can be formed on the same substrate. Therefore, the light-receiving element 270PD can be incorporated into the display device without significantly increasing the number of manufacturing steps.

[0161] The display device 280A shows an example in which the light receiving element 270PD and the light emitting element have a common configuration, except that the active layer 273 of the light receiving element 270PD and the light emitting layer 283 of the light emitting element are fabricated separately. However, the configuration of the light receiving element 270PD and the light emitting element is not limited to this. The light receiving element 270PD and the light emitting element may have layers fabricated separately from each other, in addition to the active layer 273 and the light emitting layer 283. It is preferable that the light receiving element 270PD and the light emitting element have one or more layers used in common (common layers). This allows the light receiving element 270PD to be incorporated into the display device without significantly increasing the number of manufacturing steps.

[0162] A conductive film that transmits visible light is used for the electrode from which light is extracted, between the pixel electrode 271 and the common electrode 275. It is preferable to use a conductive film that reflects visible light for the electrode from which light is not extracted.

[0163] The light-emitting element included in the display device of this embodiment preferably has a micro-optical resonator (microcavity) structure. Therefore, one of a pair of electrodes included in the light-emitting element preferably has an electrode that is transparent and reflective to visible light (semi-transmissive / semi-reflective electrode), and the other preferably has an electrode that is reflective to visible light (reflective electrode). When the light-emitting element has a microcavity structure, light emitted from the light-emitting layer can be resonated between both electrodes, thereby intensifying the light emitted from the light-emitting element.

[0164] The semi-transmitting / semi-reflective electrode can have a laminated structure of a reflective electrode and an electrode that is transparent to visible light (also called a transparent electrode).

[0165] The light transmittance of the transparent electrode is 40% or more. For example, it is preferable to use an electrode with a visible light (light with a wavelength of 400 nm or more and less than 750 nm) transmittance of 40% or more for the light emitting element. The visible light reflectance of the semi-transmissive / semi-reflective electrode is 10% or more and 95% or less, preferably 30% or more and 80% or less. The visible light reflectance of the reflective electrode is 40% or more and 100% or less, preferably 70% or more and 100% or less. In addition, the resistivity of these electrodes is 1×10 -2 When the light-emitting element emits near-infrared light (light with a wavelength of 750 nm or more and 1300 nm or less), the transmittance or reflectance of these electrodes for near-infrared light preferably satisfies the above-mentioned numerical range, similar to the transmittance or reflectance for visible light.

[0166] The light-emitting element has at least the light-emitting layer 283. The light-emitting element may further have, in addition to the light-emitting layer 283, a layer containing a substance with high hole-injection properties, a substance with high hole-transport properties, a hole-blocking material, a substance with high electron-transport properties, a substance with high electron-injection properties, an electron-blocking material, a bipolar substance (a substance with high electron-transport properties and high hole-transport properties), or the like.

[0167] For example, the light-emitting element and the light-receiving element may have one or more layers of the hole injection layer, hole transport layer, electron transport layer, and electron injection layer in common, or the light-emitting element and the light-receiving element may have one or more layers of the hole injection layer, hole transport layer, electron transport layer, and electron injection layer formed differently from each other.

[0168] The hole injection layer is a layer that injects holes from the anode into the hole transport layer and contains a material with high hole injection properties, such as an aromatic amine compound or a composite material containing a hole transport material and an acceptor material (electron acceptor material).

[0169] In a light-emitting element, the hole transport layer is a layer that transports holes injected from the anode by the hole injection layer to the light-emitting layer. In a light-receiving element, the hole transport layer is a layer that transports holes generated in the active layer based on incident light to the anode. The hole transport layer is a layer that contains a hole transport material. The hole transport material is a material having a concentration of 1×10 -6 cm 2 A material having a hole mobility of 1 / Vs or more is preferred. Note that other materials can also be used as long as they have a higher hole transporting property than electron transporting property. As the hole transporting material, a material having a high hole transporting property, such as a π-electron-rich heteroaromatic compound (e.g., a carbazole derivative, a thiophene derivative, a furan derivative, etc.) or an aromatic amine (a compound having an aromatic amine skeleton), is preferred.

[0170] In a light-emitting element, the electron transport layer is a layer that transports electrons injected from the cathode by the electron injection layer to the light-emitting layer. In a light-receiving element, the electron transport layer is a layer that transports electrons generated in the active layer based on incident light to the cathode. The electron transport layer is a layer that contains an electron transporting material. The electron transporting material is a material having a 1×10 -6 cm 2A substance having an electron mobility of 1 / Vs or more is preferred. Note that other substances can also be used as long as they have a higher electron transporting property than holes. Examples of electron-transporting materials that can be used include metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, and metal complexes having a thiazole skeleton, as well as oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives having a quinoline ligand, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, and π-electron-deficient heteroaromatic compounds including nitrogen-containing heteroaromatic compounds.

[0171] The electron injection layer is a layer that injects electrons from the cathode to the electron transport layer and contains a material with high electron injection properties. Examples of the material with high electron injection properties include alkali metals, alkaline earth metals, and compounds thereof. Examples of the material with high electron injection properties include a composite material containing an electron transport material and a donor material (electron donor material).

[0172] The light-emitting layer 283 is a layer containing a light-emitting substance. The light-emitting layer 283 can have one or more types of light-emitting substances. As the light-emitting substance, a substance that emits light of a color such as blue, purple, blue-purple, green, yellow-green, yellow, orange, or red is appropriately used. Furthermore, as the light-emitting substance, a substance that emits near-infrared light can also be used.

[0173] Examples of light-emitting materials include fluorescent materials, phosphorescent materials, TADF materials, and quantum dot materials.

[0174] Examples of fluorescent materials include pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives.

[0175] Examples of phosphorescent materials include organometallic complexes (particularly iridium complexes) having a 4H-triazole skeleton, a 1H-triazole skeleton, an imidazole skeleton, a pyrimidine skeleton, a pyrazine skeleton, or a pyridine skeleton; organometallic complexes (particularly iridium complexes) having a phenylpyridine derivative having an electron-withdrawing group as a ligand; platinum complexes; and rare earth metal complexes.

[0176] The light-emitting layer 283 may contain one or more organic compounds (host materials, assist materials, etc.) in addition to a light-emitting substance (guest material). As the one or more organic compounds, one or both of a hole-transporting material and an electron-transporting material can be used. Furthermore, as the one or more organic compounds, a bipolar material or a TADF material can be used.

[0177] The light-emitting layer 283 preferably includes, for example, a phosphorescent material and a hole-transporting material and an electron-transporting material that are a combination that easily forms an exciplex. This structure allows efficient emission using Exciplex-Triplet Energy Transfer (ExTET), which is energy transfer from an exciplex to a light-emitting substance (phosphorescent material). By selecting a combination that forms an exciplex that emits light that overlaps with the wavelength of the lowest-energy absorption band of the light-emitting substance, the energy transfer becomes smooth and light emission can be achieved efficiently. This structure simultaneously enables high efficiency, low-voltage operation, and long life of the light-emitting element.

[0178] As a combination of materials that form an exciplex, it is preferable that the HOMO level (highest occupied molecular orbital level) of the hole-transporting material is equal to or higher than the HOMO level of the electron-transporting material. It is also preferable that the LUMO level (lowest unoccupied molecular orbital level) of the hole-transporting material is equal to or higher than the LUMO level of the electron-transporting material. The LUMO level and HOMO level of the material can be derived from the electrochemical properties (reduction potential and oxidation potential) of the material measured by cyclic voltammetry (CV).

[0179] The formation of exciplexes can be confirmed, for example, by comparing the emission spectra of the hole-transporting material, the electron-transporting material, and the mixed film of these materials and observing the phenomenon that the emission spectrum of the mixed film is shifted to longer wavelengths than the emission spectra of each material (or has a new peak at longer wavelengths). Alternatively, it can be confirmed by comparing the transient photoluminescence (PL) of the hole-transporting material, the transient PL of the electron-transporting material, and the mixed film of these materials and observing differences in transient response, such as the transient PL lifetime of the mixed film having a longer-lived component or a larger proportion of delayed components than the transient PL lifetimes of the individual materials. The above-mentioned transient PL can also be interpreted as transient electroluminescence (EL). In other words, the formation of exciplexes can also be confirmed by comparing the transient EL of the hole-transporting material, the transient EL of the electron-transporting material, and the mixed film of these materials and observing differences in transient response.

[0180] The active layer 273 includes a semiconductor. Examples of the semiconductor include inorganic semiconductors such as silicon and organic semiconductors including organic compounds. In this embodiment, an example in which an organic semiconductor is used as the semiconductor included in the active layer 273 is shown. By using an organic semiconductor, the light-emitting layer 283 and the active layer 273 can be formed by the same method (for example, vacuum deposition), which is preferable because it allows the use of a common manufacturing device.

[0181] The active layer 273 has an n-type semiconductor material, such as fullerene (e.g., C 60 , C 70Examples of electron-accepting organic semiconductor materials include fullerene derivatives and other fullerenes. Fullerenes have a soccer ball-like shape, which is energetically stable. Fullerenes have deep (low) HOMO and LUMO levels. Because fullerenes have a deep LUMO level, they have extremely high electron-accepting (acceptor) properties. Normally, when the π-electron conjugation (resonance) spreads on a plane, as in benzene, the electron-donating (donor) properties increase, but fullerenes have a spherical shape, so they have high electron-accepting properties despite the large spread of π-electrons. High electron-accepting properties allow charge separation to occur quickly and efficiently, making them useful as light-receiving elements. C 60 , C 70 Both have a wide absorption band in the visible light region, especially C 70 is C 60 It is preferred because it has a larger π-electron conjugated system and a wide absorption band in the long wavelength region compared to the above.

[0182] Furthermore, examples of n-type semiconductor materials include metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, metal complexes having a thiazole skeleton, oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, naphthalene derivatives, anthracene derivatives, coumarin derivatives, rhodamine derivatives, triazine derivatives, and quinone derivatives.

[0183] Examples of the p-type semiconductor material of the active layer 273 include electron-donating organic semiconductor materials such as copper(II) phthalocyanine (CuPc), tetraphenyldibenzoperiflanthene (DBP), zinc phthalocyanine (ZnPc), tin phthalocyanine (SnPc), and quinacridone.

[0184] Examples of p-type semiconductor materials include carbazole derivatives, thiophene derivatives, furan derivatives, compounds having an aromatic amine skeleton, etc. Examples of p-type semiconductor materials include naphthalene derivatives, anthracene derivatives, pyrene derivatives, triphenylene derivatives, fluorene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, indole derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, indolocarbazole derivatives, porphyrin derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, quinacridone derivatives, polyphenylenevinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, polythiophene derivatives, etc.

[0185] The HOMO level of the electron-donating organic semiconductor material is preferably shallower (higher) than the HOMO level of the electron-accepting organic semiconductor material, and the LUMO level of the electron-donating organic semiconductor material is preferably shallower (higher) than the LUMO level of the electron-accepting organic semiconductor material.

[0186] It is preferable to use a spherical fullerene as the electron-accepting organic semiconductor material and a planar organic semiconductor material as the electron-donating organic semiconductor material. Molecules with similar shapes tend to aggregate together, and when molecules of the same type aggregate, the energy levels of their molecular orbitals become close, which can improve carrier transport properties.

[0187] For example, the active layer 273 is preferably formed by co-evaporating an n-type semiconductor and a p-type semiconductor, or alternatively, the active layer 273 may be formed by laminating an n-type semiconductor and a p-type semiconductor.

[0188] The light-emitting element and the light-receiving element (e.g., the common layer and the light-emitting layer) can be made of either a low-molecular-weight compound or a high-molecular-weight compound, and may contain an inorganic compound. The layers constituting the light-emitting element and the light-receiving element can be formed by a deposition method (including a vacuum deposition method), a transfer method, a printing method, an inkjet method, a coating method, or the like.

[0189] Display device 280B shown in FIG. 7B differs from display device 280A in that light receiving element 270PD and light emitting element 270R have the same configuration.

[0190] The light receiving element 270PD and the light emitting element 270R have the active layer 273 and the light emitting layer 283R in common.

[0191] Here, it is preferable that light receiving element 270PD has a common configuration with a light emitting element that emits light of a longer wavelength than the light to be detected. For example, light receiving element 270PD configured to detect blue light can have the same configuration as one or both of light emitting element 270R and light emitting element 270G. For example, light receiving element 270PD configured to detect green light can have the same configuration as light emitting element 270R.

[0192] By using a common configuration for the light receiving element 270PD and the light emitting element 270R, the number of film formation steps and the number of masks can be reduced compared to a configuration in which the light receiving element 270PD and the light emitting element 270R have separate layers, thereby reducing the manufacturing steps and manufacturing costs of the display device.

[0193] Furthermore, by using a common configuration for the light receiving element 270PD and the light emitting element 270R, the margin for misalignment can be narrowed compared to a configuration in which the light receiving element 270PD and the light emitting element 270R have separate layers. This allows for an increased pixel aperture ratio, improving the light extraction efficiency of the display device. This also extends the life of the light emitting element. Furthermore, the display device can display high brightness. Furthermore, it also allows for higher resolution display devices.

[0194] Light-emitting layer 283R includes a light-emitting material that emits red light. Active layer 273 includes an organic compound that absorbs light with a wavelength shorter than red (for example, one or both of green light and blue light). Active layer 273 preferably includes an organic compound that does not easily absorb red light and absorbs light with a wavelength shorter than red. This allows red light to be extracted efficiently from light-emitting element 270R, and light-receiving element 270PD to detect light with a wavelength shorter than red with high accuracy.

[0195] Furthermore, in the display device 280B, an example is shown in which the light emitting element 270R and the light receiving element 270PD have the same configuration, but the light emitting element 270R and the light receiving element 270PD may have optical adjustment layers of different thicknesses.

[0196] 8A and 8B includes a light receiving / emitting element 270SR, a light emitting element 270G, and a light emitting element 270B that emit red (R) light and have a light receiving function. The configuration of the light emitting element 270G and the light emitting element 270B can be based on the configuration of the display device 280A described above.

[0197] The light emitting / receiving element 270SR has, stacked in this order, a pixel electrode 271, a hole injection layer 281, a hole transport layer 282, an active layer 273, a light emitting layer 283R, an electron transport layer 284, an electron injection layer 285, and a common electrode 275. The light emitting / receiving element 270SR has the same configuration as the light emitting element 270R and the light receiving element 270PD exemplified in the display device 280B.

[0198] Fig. 8A shows a case where the light emitting / receiving element 270SR functions as a light emitting element. Fig. 8A shows an example where the light emitting element 270B emits blue light, the light emitting element 270G emits green light, and the light emitting / receiving element 270SR emits red light.

[0199] Fig. 8B shows a case where the light receiving / emitting element 270SR functions as a light receiving element. Fig. 8B shows an example where the light receiving / emitting element 270SR receives blue light emitted by the light emitting element 270B and green light emitted by the light emitting element 270G.

[0200] The light emitting element 270B, the light emitting element 270G, and the light emitting / receiving element 270SR each have a pixel electrode 271 and a common electrode 275. In the present embodiment, a case will be described as an example in which the pixel electrode 271 functions as an anode and the common electrode 275 functions as a cathode. The light emitting / receiving element 270SR is driven by applying a reverse bias between the pixel electrode 271 and the common electrode 275, whereby it can detect light incident on the light emitting / receiving element 270SR, generate electric charges, and extract the charges as a current.

[0201] The light emitting / receiving element 270SR can be said to have a configuration in which the active layer 273 is added to the light emitting element. In other words, the light emitting / receiving element 270SR can be formed in parallel with the formation of the light emitting element by simply adding a process for forming the active layer 273 to the manufacturing process of the light emitting element. Furthermore, the light emitting element and the light emitting / receiving element can be formed on the same substrate. Therefore, it is possible to provide the display unit with either or both of an imaging function and a sensing function without significantly increasing the manufacturing process.

[0202] There are no limitations on the stacking order of the light-emitting layer 283R and the active layer 273. Figures 8A and 8B show an example in which the active layer 273 is provided on the hole transport layer 282, and the light-emitting layer 283R is provided on the active layer 273. The stacking order of the light-emitting layer 283R and the active layer 273 may be reversed.

[0203] Furthermore, the light emitting / receiving element may not have at least one layer selected from the hole injection layer 281, the hole transport layer 282, the electron transport layer 284, and the electron injection layer 285. The light emitting / receiving element may also have other functional layers such as a hole blocking layer and an electron blocking layer.

[0204] In the light emitting / receiving element, a conductive film that transmits visible light is used for the electrode on the light extraction side, and a conductive film that reflects visible light is preferably used for the electrode on the non-light extraction side.

[0205] The functions and materials of the layers constituting the light emitting / receiving element are similar to those of the layers constituting the light emitting element and the light receiving element, and therefore detailed description thereof will be omitted.

[0206] 8C to 8G show examples of the stacked structure of the light emitting and receiving element.

[0207] The light emitting / receiving element shown in FIG. 8C has a first electrode 277, a hole injection layer 281, a hole transport layer 282, a light emitting layer 283R, an active layer 273, an electron transport layer 284, an electron injection layer 285, and a second electrode 278.

[0208] FIG. 8C shows an example in which a light-emitting layer 283R is provided on a hole-transporting layer 282, and an active layer 273 is laminated on the light-emitting layer 283R.

[0209] As shown in FIGS. 8A to 8C, the active layer 273 and the light-emitting layer 283R may be in contact with each other.

[0210] Furthermore, a buffer layer is preferably provided between the active layer 273 and the light-emitting layer 283R. In this case, the buffer layer preferably has hole transport properties and electron transport properties. For example, a bipolar substance is preferably used for the buffer layer. Alternatively, the buffer layer may be at least one layer selected from a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a hole blocking layer, and an electron blocking layer. FIG. 8D shows an example in which a hole transport layer 282 is used as the buffer layer.

[0211] By providing a buffer layer between the active layer 273 and the light-emitting layer 283R, it is possible to suppress the transfer of excitation energy from the light-emitting layer 283R to the active layer 273. In addition, the buffer layer can also be used to adjust the optical path length (cavity length) of the microcavity structure. Therefore, a light-emitting / receiving element having a buffer layer between the active layer 273 and the light-emitting layer 283R can obtain high light-emitting efficiency.

[0212] FIG. 8E shows an example of a laminated structure in which a hole transport layer 282-1, an active layer 273, a hole transport layer 282-2, and an emitting layer 283R are laminated in this order on a hole injection layer 281. The hole transport layer 282-2 functions as a buffer layer. The hole transport layer 282-1 and the hole transport layer 281-2 may contain the same material or different materials. Alternatively, a layer that can be used as the buffer layer described above may be used instead of the hole transport layer 281-2. Alternatively, the positions of the active layer 273 and the emitting layer 283R may be interchanged.

[0213] 8F differs from the light emitting / receiving element shown in Fig. 8A in that it does not have the hole transport layer 282. In this way, the light emitting / receiving element may not have at least one layer among the hole injection layer 281, the hole transport layer 282, the electron transport layer 284, and the electron injection layer 285. In addition, the light emitting / receiving element may have other functional layers such as a hole blocking layer or an electron blocking layer.

[0214] The light emitting / receiving device shown in FIG. 8G differs from the light emitting / receiving device shown in FIG. 8A in that it does not have active layer 273 and light emitting layer 283R, but has layer 289 that serves as both a light emitting layer and an active layer.

[0215] The layer 289 serving as both the light-emitting layer and the active layer can be, for example, a layer containing three materials: an n-type semiconductor that can be used for the active layer 273, a p-type semiconductor that can be used for the active layer 273, and a light-emitting substance that can be used for the light-emitting layer 283R.

[0216] It is preferable that the lowest energy absorption band in the absorption spectrum of the mixed material of n-type and p-type semiconductors does not overlap with the maximum peak in the emission spectrum (PL spectrum) of the luminescent substance, and it is more preferable that they are sufficiently separated from each other.

[0217] [Display device configuration example 4] A more specific structure of the display device of one embodiment of the present invention will be described below.

[0218] FIG. 9 shows a perspective view of the display device 200, and FIG. 10A shows a cross-sectional view of the display device 200.

[0219] The display device 200 has a configuration in which a substrate 151 and a substrate 152 are bonded together. In Fig. 9, the substrate 152 is clearly indicated by a dashed line.

[0220] The display device 200 has a display unit 262, a circuit 264, wiring 265, etc. Fig. 9 shows an example in which an IC (integrated circuit) 274 and an FPC 272 are mounted on the display device 200. Therefore, the configuration shown in Fig. 9 can also be said to be a display module having the display device 200, an IC, and an FPC.

[0221] The circuit 264 can be, for example, a scanning line driver circuit.

[0222] The wiring 265 has a function of supplying signals and power to the display unit 262 and the circuit 264. The signals and power are input to the wiring 265 from the outside via the FPC 272 or input to the wiring 265 from the IC 274.

[0223] 9 shows an example in which an IC 274 is provided on the substrate 151 by a COG (Chip On Glass) method or a COF (Chip On Film) method. The IC 274 may be, for example, an IC having a scanning line driving circuit or a signal line driving circuit. The display device 200 and the display module may be configured without an IC. Alternatively, the IC may be mounted on an FPC by a COF method or the like.

[0224] Figure 10A shows an example of a cross section of the display device 200 shown in Figure 9, where a portion of the area including the FPC 272, a portion of the area including the circuit 264, a portion of the area including the display unit 262, and a portion of the area including the end portion are cut away.

[0225] The display device 200 shown in FIG. 10A has a transistor 208, a transistor 209, a transistor 210, a light-emitting element 190, a light-receiving element 110, a light-emitting element 160, and the like between a substrate 151 and a substrate 152.

[0226] The transistor 208, the transistor 209, and the transistor 210 are all formed over a substrate 151. These transistors can be manufactured using the same material and the same process.

[0227] The transistor 208, the transistor 209, and the transistor 210 each include a conductive layer 221 functioning as a gate, an insulating layer 211 functioning as a gate insulating layer, a semiconductor layer including a channel formation region 231i and a pair of low-resistance regions 231n, a conductive layer 222a connected to one of the pair of low-resistance regions 231n, a conductive layer 222b connected to the other of the pair of low-resistance regions 231n, an insulating layer 225 functioning as a gate insulating layer, a conductive layer 223 functioning as a gate, and an insulating layer 215 covering the conductive layer 223. The insulating layer 211 is located between the conductive layer 221 and the channel formation region 231i. The insulating layer 225 is located between the conductive layer 223 and the channel formation region 231i.

[0228] The conductive layer 222a and the conductive layer 222b are connected to the low-resistance region 231n through openings provided in the insulating layer 225 and the insulating layer 215, respectively. One of the conductive layer 222a and the conductive layer 222b functions as a source, and the other functions as a drain.

[0229] The structure of the transistor included in the display device of this embodiment is not particularly limited. For example, a planar transistor, a staggered transistor, an inverted staggered transistor, or the like can be used. Furthermore, either a top-gate transistor or a bottom-gate transistor structure may be used. Alternatively, gates may be provided above and below a semiconductor layer in which a channel is formed.

[0230] The transistors 208, 209, and 210 each have a structure in which a semiconductor layer in which a channel is formed is sandwiched between two gates. The two gates may be connected and supplied with the same signal to drive the transistor. Alternatively, the threshold voltage of the transistor may be controlled by applying a potential for controlling the threshold voltage to one of the two gates and a potential for driving the other.

[0231] The crystallinity of the semiconductor material used for the transistor is not particularly limited, and any of an amorphous semiconductor, a single-crystal semiconductor, and a semiconductor having crystallinity other than single crystal (a microcrystalline semiconductor, a polycrystalline semiconductor, or a semiconductor having a crystalline region in part) may be used. The use of a single-crystal semiconductor or a crystalline semiconductor is preferable because it can suppress deterioration of the transistor characteristics.

[0232] The semiconductor layer of the transistor preferably contains a metal oxide (also referred to as an oxide semiconductor). Alternatively, the semiconductor layer of the transistor may contain silicon. Examples of silicon include amorphous silicon and crystalline silicon (such as low-temperature polysilicon and single-crystal silicon).

[0233] The semiconductor layer preferably contains, for example, indium, M (wherein M is one or more elements selected from gallium, aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium), and zinc. In particular, M is preferably one or more elements selected from aluminum, gallium, yttrium, and tin.

[0234] In particular, it is preferable to use an oxide containing indium (In), gallium (Ga), and zinc (Zn) (also referred to as IGZO) as the semiconductor layer.

[0235] When the semiconductor layer is an In-M-Zn oxide, the sputtering target used to deposit the In-M-Zn oxide preferably has an atomic ratio of In equal to or greater than the atomic ratio of M. Examples of atomic ratios of metal elements in such sputtering targets include In:M:Zn=1:1:1, In:M:Zn=1:1:1.2, In:M:Zn=2:1:3, In:M:Zn=3:1:2, In:M:Zn=4:2:3, In:M:Zn=4:2:4.1, In:M:Zn=5:1:3, In:M:Zn=5:1:6, In:M:Zn=5:1:7, In:M:Zn=5:1:8, In:M:Zn=10:1:3, In:M:Zn=6:1:6, and In:M:Zn=5:2:5.

[0236] As the sputtering target, a target containing a polycrystalline oxide is preferably used because it facilitates the formation of a crystalline semiconductor layer. The atomic ratio of the semiconductor layer to be formed can vary by ±40% of the atomic ratio of the metal elements contained in the sputtering target. For example, if the composition of the sputtering target used for the semiconductor layer is In:Ga:Zn=4:2:4.1 [atomic ratio], the composition of the semiconductor layer to be formed may be close to In:Ga:Zn=4:2:3 [atomic ratio].

[0237] When describing an atomic ratio of In:Ga:Zn=4:2:3 or thereabout, this includes a case where, when In is taken as 4, Ga is 1 to 3 and Zn is 2 to 4. When describing an atomic ratio of In:Ga:Zn=5:1:6 or thereabout, this includes a case where, when In is taken as 5, Ga is more than 0.1 and 2 or less and Zn is 5 to 7. When describing an atomic ratio of In:Ga:Zn=1:1:1 or thereabout, this includes a case where, when In is taken as 1, Ga is more than 0.1 and 2 or less and Zn is more than 0.1 and 2 or less.

[0238] The transistors included in the circuit 264 may have the same structure as or different from the transistors included in the display portion 262. The transistors included in the circuit 264 may all have the same structure or may have two or more types. Similarly, the transistors included in the display portion 262 may all have the same structure or may have two or more types.

[0239] The insulating layer 214 is provided to cover the transistor and functions as a planarization layer. Note that the number of gate insulating layers and the number of insulating layers covering the transistor are not limited, and each may be a single layer or two or more layers.

[0240] It is preferable that at least one insulating layer covering the transistor is made of a material that is difficult for impurities such as water or hydrogen to diffuse into. This allows the insulating layer to function as a barrier layer. With this structure, it is possible to effectively prevent impurities from diffusing into the transistor from the outside, thereby improving the reliability of the display device.

[0241] 10A shows an example in which the insulating layer 225 covers the top and side surfaces of the semiconductor layer. On the other hand, in the transistor 202 shown in FIG. 10B, the insulating layer 225 overlaps with the channel formation region 231i of the semiconductor layer 231 but does not overlap with the low-resistance region 231n. For example, the structure shown in FIG. 10B can be manufactured by processing the insulating layer 225 using the conductive layer 223 as a mask. In FIG. 10B, the insulating layer 215 is provided to cover the insulating layer 225 and the conductive layer 223, and the conductive layer 222a and the conductive layer 222b are each connected to the low-resistance region 231n through openings in the insulating layer 215. Furthermore, an insulating layer 218 may be provided to cover the transistor.

[0242] It is preferable to use an inorganic insulating film for each of the insulating layer 211, the insulating layer 225, and the insulating layer 215. Examples of the inorganic insulating film that can be used include a silicon nitride film, a silicon oxynitride film, a silicon oxide film, a silicon nitride oxide film, an aluminum oxide film, and an aluminum nitride film. Alternatively, a hafnium oxide film, an yttrium oxide film, a zirconium oxide film, a gallium oxide film, a tantalum oxide film, a magnesium oxide film, a lanthanum oxide film, a cerium oxide film, and a neodymium oxide film may also be used. Two or more of the above insulating films may be stacked.

[0243] Here, organic insulating films often have lower barrier properties than inorganic insulating films. Therefore, it is preferable that the organic insulating film has an opening near the edge of the display device 200. This makes it possible to suppress the diffusion of impurities from the edge of the display device 200 through the organic insulating film. Alternatively, the organic insulating film may be formed so that the edge of the organic insulating film is located more inward than the edge of the display device 200, so that the organic insulating film is not exposed at the edge of the display device 200.

[0244] An organic insulating film is suitable for the insulating layer 214, which functions as a planarizing layer. Materials that can be used for the organic insulating film include acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimideamide resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins.

[0245] 10A, an opening is formed in insulating layer 214. This makes it possible to prevent impurities from diffusing from the outside into display section 262 through insulating layer 214, even when an organic insulating film is used for insulating layer 214. This makes it possible to improve the reliability of display device 200.

[0246] The light-emitting element 190 has a layered structure in which a pixel electrode 191, a common layer 114, a light-emitting layer 196, a common layer 115, and a common electrode 113 are layered in this order from the insulating layer 214 side. The pixel electrode 191 of the light-emitting element 190 is electrically connected to one of a pair of low-resistance regions 231n of the transistor 208 via a conductive layer 222b. The transistor 208 has a function of controlling driving of the light-emitting element 190. An end of the pixel electrode 191 is covered with a partition wall 216. The pixel electrode 191 contains a material that reflects visible light, and the common electrode 113 contains a material that transmits visible light.

[0247] The light-receiving element 110 has a layered structure in which a pixel electrode 111, a common layer 114, an active layer 116, a common layer 115, and a common electrode 113 are layered in this order from the insulating layer 214 side. The pixel electrode 111 of the light-receiving element 110 is electrically connected to the other of the pair of low-resistance regions 231n of the transistor 209 via a conductive layer 222b. An end of the pixel electrode 111 is covered with a partition wall 216. The pixel electrode 111 contains a material that reflects visible light and infrared light, and the common electrode 113 contains a material that transmits visible light and infrared light.

[0248] Light emitted by the light emitting element 190 is emitted toward the substrate 152. Furthermore, light is incident on the light receiving element 110 via the substrate 152. For the substrate 152, it is preferable to use a material that is highly transparent to visible light and infrared light.

[0249] The pixel electrode 111 and the pixel electrode 191 can be manufactured using the same material and the same process. The common layer 114, the common layer 115, and the common electrode 113 are used for both the light receiving element 110 and the light emitting element 190. The light receiving element 110 and the light emitting element 190 can have the same configuration except for the configurations of the active layer 116 and the light emitting layer 196. This allows the light receiving element 110 to be built into the display device 200 without significantly increasing the number of manufacturing processes.

[0250] Furthermore, an inorganic insulating layer 195a, an organic insulating layer 195b, and an inorganic insulating layer 195c are laminated to cover the light receiving element 110 and the light emitting element 190. Furthermore, a light blocking layer 145 and a light emitting element 160 are laminated on the inorganic insulating layer 195c. The light blocking layer 145 and the light emitting element 160 are provided at positions that do not overlap with the light receiving region of the light receiving element 110 and the light emitting region of the light emitting element 190.

[0251] In the display device 200, the organic insulating layer 195b corresponds to the resin layer 141. Note that a configuration may be adopted in which part of the organic insulating layer 195b and part of the resin layer 142 are in contact with each other, without providing the inorganic insulating layer 195c.

[0252] The ends of the inorganic insulating layer 195a and the inorganic insulating layer 195c extend outward beyond the ends of the organic insulating layer 195b and are in contact with each other. The inorganic insulating layer 195a is in contact with the insulating layer 215 (inorganic insulating layer) through an opening in the insulating layer 214 (organic insulating layer). This allows the insulating layer 215 and the protective layer 195 to surround the light receiving element 110 and the light emitting element 190, thereby improving the reliability of the light receiving element 110 and the light emitting element 190.

[0253] In this way, the protective layer 195 may have a laminated structure of an organic insulating film and an inorganic insulating film. In this case, it is preferable that the end of the inorganic insulating film extends further outward than the end of the organic insulating film.

[0254] The light-shielding layer 145 has openings at positions overlapping the light-receiving element 110 and the light-emitting element 190. By providing the light-shielding layer 145, the range in which the light-receiving element 110 detects light can be controlled. Furthermore, by providing the light-shielding layer 145, it is possible to prevent light from the light-emitting element 190 and the light-emitting element 160 from directly entering the light-receiving element 110. Therefore, a sensor with low noise and high sensitivity can be realized.

[0255] The light emitting element 160, the insulating layer 217, etc. are provided on the substrate 152 side. The light emitting element 160 is a bottom emission type light emitting element that emits light toward the surface on which it is formed.

[0256] The light-emitting element 160 has a layered structure in which an electrode 161, a buffer layer 164, a light-emitting layer 166, a buffer layer 165, and an electrode 163 are layered in this order from the substrate 152 side. An end of the electrode 161 is covered with an insulating layer 217. The electrode 161 contains a material that transmits infrared light, and the electrode 163 contains a material that reflects visible light and infrared light.

[0257] The buffer layer 164, the light-emitting layer 166, and the buffer layer 165 have island-shaped upper surfaces. The electrode 163 is provided to cover the buffer layer 164, the light-emitting layer 166, and the buffer layer 165. The buffer layer 164, the light-emitting layer 166, the buffer layer 165, and the electrode 163 are provided at positions that do not overlap with the light-receiving region of the light-receiving element 110 and the light-emitting region of the light-emitting element 190.

[0258] 10A shows an example in which a passive matrix method or a segment method can be applied as a driving method for the light emitting elements 160. In this case, the electrodes 161 and 163 are provided in common to the plurality of light emitting elements 160.

[0259] When an active matrix system is applied as a driving system for the light-emitting element 160, a transistor can be provided between the light-emitting element 160 and the substrate 152. In this case, similar to the light-emitting element 190, the electrode 161 can have an island-shaped top surface and be electrically connected to one of the source and drain of the transistor. In this case, the electrode 161 functions as a pixel electrode. The structure between the electrode 161 and the substrate 152 can be the same as that of the light-emitting element 190, the transistor 208, and their surrounding layer structures.

[0260] A resin layer 142 is provided to cover the insulating layer 217 and the light emitting element 160. The resin layer 142 is also provided to cover the light blocking layer 145 provided on the substrate 151 side. The resin layer 142 functions as an adhesive layer for bonding the substrates 151 and 152 together.

[0261] A connection section 204 is provided in an area of ​​the substrate 151 where the substrate 152 does not overlap. In the connection section 204, a wiring 265 is electrically connected to the FPC 272 via a conductive layer 266 and a connection layer 242. The conductive layer 266, which is obtained by processing the same conductive film as the pixel electrode 191, is exposed on the upper surface of the connection section 204. This allows the connection section 204 and the FPC 272 to be electrically connected via the connection layer 242.

[0262] Various optical members can be disposed on the outside of the substrate 152. Examples of optical members include a polarizing plate, a retardation plate, a light diffusion layer (such as a diffusion film), an anti-reflection layer, and a light collecting film. In addition, an anti-static film that suppresses the adhesion of dust, a water-repellent film that makes it difficult for dirt to adhere, a hard coat film that suppresses scratches caused by use, an impact absorbing layer, etc. may be disposed on the outside of the substrate 152.

[0263] The substrate 151 and the substrate 152 can each be made of glass, quartz, ceramic, sapphire, resin, etc. Using a flexible material for the substrate 151 and the substrate 152 can increase the flexibility of the display device.

[0264] The adhesive layer can be made of various curable adhesives, such as photo-curable adhesives (e.g., ultraviolet curable), reactive curable adhesives, thermosetting adhesives, and anaerobic adhesives. Examples of such adhesives include epoxy resin, acrylic resin, silicone resin, phenolic resin, polyimide resin, imide resin, PVC (polyvinyl chloride) resin, PVB (polyvinyl butyral) resin, and EVA (ethylene vinyl acetate) resin. Materials with low moisture permeability, such as epoxy resin, are particularly preferred. Two-component resins may also be used. Adhesive sheets, etc., may also be used.

[0265] The connection layer 242 may be made of an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), or the like.

[0266] Here, a top-emission type light-emitting element is used as the light-emitting element 190, and a bottom-emission type light-emitting element is used as the light-emitting element 160, but light-emitting elements may be top-emission, bottom-emission, dual-emission, or the like. A conductive film that transmits visible light is used for the electrode on the side from which light is extracted. In addition, a conductive film that reflects visible light is preferably used for the electrode on the side from which light is not extracted.

[0267] Materials that can be used for conductive layers such as the gate, source, and drain of a transistor, as well as various wirings and electrodes that constitute a display device include metals such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, and tungsten, and alloys containing these metals as main components, etc. Films containing these materials can be used as a single layer or a stacked layer structure.

[0268] Examples of light-transmitting conductive materials include conductive oxides such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, and zinc oxide containing gallium, or graphene. Alternatively, metal materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, and titanium, or alloy materials containing such metal materials, can be used. Alternatively, nitrides of such metal materials (e.g., titanium nitride) can be used. When using metal materials or alloy materials (or their nitrides), it is preferable to thin them sufficiently to ensure light-transmitting properties. A stacked film of the above materials can also be used as a conductive layer. For example, a stacked film of an alloy of silver and magnesium and indium tin oxide is preferable because it can enhance conductivity. These can also be used for conductive layers such as various wirings and electrodes constituting a display device, or conductive layers (conductive layers functioning as pixel electrodes, common electrodes, etc.) in a display element.

[0269] Examples of insulating materials that can be used for each insulating layer include resins such as acrylic resin and epoxy resin, and inorganic insulating materials such as silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, aluminum oxide, and hafnium oxide.

[0270] [About metal oxides] Metal oxides applicable to the semiconductor layer will be described below.

[0271] In this specification and the like, nitrogen-containing metal oxides may also be collectively referred to as metal oxides. Nitrogen-containing metal oxides may also be referred to as metal oxynitrides. For example, nitrogen-containing metal oxides such as zinc oxynitride (ZnON) may be used for the semiconductor layer.

[0272] In this specification, etc., they may be referred to as CAAC (c-axis aligned crystal) and CAC (Cloud-Aligned Composite). CAAC represents an example of a crystal structure, and CAC represents an example of a function or material configuration.

[0273] For example, the semiconductor layer can be made of a cloud-aligned composite (CAC)-oxide semiconductor (OS).

[0274] CAC-OS or CAC-metal oxide has a conductive function in part of the material and an insulating function in part of the material, and functions as a semiconductor as a whole. When CAC-OS or CAC-metal oxide is used in the semiconductor layer of a transistor, the conductive function is a function of allowing electrons (or holes) to flow as carriers, and the insulating function is a function of preventing the flow of electrons as carriers. By making the conductive function and the insulating function act complementarily, a switching function (on / off function) can be imparted to CAC-OS or CAC-metal oxide. By separating the respective functions in CAC-OS or CAC-metal oxide, both functions can be maximized.

[0275] Furthermore, CAC-OS or CAC-metal oxide has conductive regions and insulating regions. The conductive regions have the above-mentioned conductive function, and the insulating regions have the above-mentioned insulating function. In addition, the conductive regions and the insulating regions may be separated at the nanoparticle level in the material. In addition, the conductive regions and the insulating regions may be unevenly distributed in the material. In addition, the conductive regions may be observed as connected in a cloud-like shape with the periphery blurred.

[0276] In addition, in CAC-OS or CAC-metal oxide, the conductive regions and the insulating regions may be dispersed in the material with sizes of 0.5 nm to 10 nm, preferably 0.5 nm to 3 nm.

[0277] Furthermore, the CAC-OS or CAC-metal oxide is composed of components with different band gaps. For example, the CAC-OS or CAC-metal oxide is composed of a component with a wide gap due to an insulating region and a component with a narrow gap due to a conductive region. In this configuration, when carriers flow, the carriers mainly flow in the component with the narrow gap. Furthermore, the component with the narrow gap acts complementarily with the component with the wide gap, and carriers also flow in the component with the wide gap in conjunction with the component with the narrow gap. Therefore, when the CAC-OS or CAC-metal oxide is used in the channel formation region of a transistor, the transistor can achieve high current driving power in the on state, i.e., a large on-state current, and high field-effect mobility.

[0278] That is, CAC-OS or CAC-metal oxide can also be called a matrix composite or a metal matrix composite.

[0279] Oxide semiconductors (metal oxides) are classified into single-crystal oxide semiconductors and other non-single-crystal oxide semiconductors, such as c-axis aligned crystalline oxide semiconductors (CAAC-OS), polycrystalline oxide semiconductors, nanocrystalline oxide semiconductors (nc-OS), amorphous-like oxide semiconductors (a-like OS), and amorphous oxide semiconductors.

[0280] CAAC-OS has a c-axis orientation and a distorted crystal structure in which multiple nanocrystals are connected in the ab-plane direction. The distorted crystal structure refers to the change in the lattice orientation between regions with a uniform lattice arrangement and regions with a different uniform lattice arrangement in the regions where multiple nanocrystals are connected.

[0281] Nanocrystals are basically hexagonal, but not necessarily regular hexagonal, and may have non-regular hexagonal shapes. The distortion may also result in pentagonal, heptagonal, or other lattice arrangements. It is difficult to identify clear grain boundaries in CAAC-OS even near the distortion. This indicates that the formation of grain boundaries is suppressed by the distortion of the lattice arrangement. This is because CAAC-OS can tolerate distortion due to the lack of close-packed oxygen atom arrangement in the ab-plane direction or the change in interatomic bond distance caused by substitution with metal elements.

[0282] CAAC-OS also tends to have a layered crystal structure (also referred to as a layered structure) in which a layer containing indium and oxygen (hereinafter referred to as an In layer) and a layer containing the element M, zinc, and oxygen (hereinafter referred to as an (M,Zn) layer) are stacked. Note that indium and the element M are mutually substituted, and when the element M in an (M,Zn) layer is substituted with indium, the layer can also be referred to as an (In,M,Zn) layer. When the indium in an In layer is substituted with the element M, the layer can also be referred to as an (In,M) layer.

[0283] CAAC-OS is a metal oxide with high crystallinity. On the other hand, it is difficult to identify clear grain boundaries in CAAC-OS, so it is said that the decrease in electron mobility due to grain boundaries is unlikely to occur. In addition, since the crystallinity of metal oxides can be decreased by the inclusion of impurities or the generation of defects, CAAC-OS is not prone to impurities and defects (oxygen vacancies (V O It can also be said that these metal oxides have low oxygen vacancies. Therefore, metal oxides with CAAC-OS have stable physical properties. Therefore, metal oxides with CAAC-OS are heat-resistant and highly reliable.

[0284] The nc-OS has periodic atomic arrangement in a small region (for example, a region of 1 nm to 10 nm, particularly a region of 1 nm to 3 nm). Furthermore, the nc-OS exhibits no regularity in the crystal orientation between different nanocrystals. Therefore, no orientation is observed throughout the film. Therefore, depending on the analytical method, the nc-OS may be indistinguishable from an a-like OS or an amorphous oxide semiconductor.

[0285] Indium-gallium-zinc oxide (IGZO), a type of metal oxide containing indium, gallium, and zinc, can sometimes have a stable structure when made into the above-mentioned nanocrystals. In particular, because IGZO tends to have difficulty growing crystals in the atmosphere, it may be structurally more stable when made into small crystals (such as the above-mentioned nanocrystals) than large crystals (here, crystals of a few millimeters or a few centimeters).

[0286] The a-like OS is a metal oxide having a structure between the nc-OS and an amorphous oxide semiconductor. The a-like OS has pores or low-density regions. That is, the a-like OS has lower crystallinity than the nc-OS and CAAC-OS.

[0287] Oxide semiconductors (metal oxides) have a variety of structures, each with different characteristics. The oxide semiconductor of one embodiment of the present invention may include two or more of an amorphous oxide semiconductor, a polycrystalline oxide semiconductor, an a-like OS, an nc-OS, and a CAAC-OS.

[0288] A metal oxide film functioning as a semiconductor layer can be formed using either or both of an inert gas and an oxygen gas. The oxygen flow rate (oxygen partial pressure) during the formation of the metal oxide film is not particularly limited. However, in order to obtain a transistor with high field-effect mobility, the oxygen flow rate (oxygen partial pressure) during the formation of the metal oxide film is preferably 0% to 30%, more preferably 5% to 30%, and even more preferably 7% to 15%.

[0289] The metal oxide preferably has an energy gap of 2 eV or more, more preferably 2.5 eV or more, and further preferably 3 eV or more. By using a metal oxide with such a wide energy gap, the off-state current of a transistor can be reduced.

[0290] The substrate temperature during deposition of the metal oxide film is preferably 350° C. or lower, more preferably room temperature or higher and 200° C. or lower, and even more preferably room temperature or higher and 130° C. If the substrate temperature during deposition of the metal oxide film is room temperature, productivity can be increased, which is preferable.

[0291] The metal oxide film can be formed by sputtering, or by other methods such as PLD, PECVD, thermal CVD, ALD, and vacuum deposition.

[0292] This concludes the explanation of metal oxides.

[0293] The display device of this embodiment has a light-receiving element and a light-emitting element in a display portion, and the display portion has both a function of displaying an image and a function of detecting light. This allows the electronic device to be made smaller and lighter than when a sensor is provided outside the display portion or the display device. Furthermore, by combining the sensor provided outside the display portion or the display device, a more multifunctional electronic device can be realized.

[0294] At least one layer of the light-receiving element, other than the active layer, can be configured in common with the light-emitting element (EL element). Furthermore, all layers of the light-receiving element, other than the active layer, can be configured in common with the light-emitting element (EL element). For example, by simply adding a process for forming an active layer to the manufacturing process of the light-emitting element, the light-emitting element and the light-receiving element can be formed on the same substrate. Furthermore, the pixel electrode and the common electrode of the light-receiving element and the light-emitting element can be formed using the same material and in the same process, respectively. Furthermore, by manufacturing the circuit electrically connected to the light-receiving element and the circuit electrically connected to the light-emitting element using the same material and in the same process, the manufacturing process of the display device can be simplified. In this way, a highly convenient display device incorporating a light-receiving element can be manufactured without complex processes.

[0295] At least a part of the configuration examples exemplified in this embodiment and the corresponding drawings can be combined as appropriate with other configuration examples or drawings.

[0296] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0297] (Embodiment 2) In this embodiment, an electronic device according to one embodiment of the present invention will be described.

[0298] [Example of electronic device configuration] The display device of one embodiment of the present invention can acquire various types of biometric information using infrared light and visible light. Such biometric information can be used for both personal authentication of users and healthcare applications.

[0299] Among biometric information that can be acquired using the display device of one embodiment of the present invention, typical examples of biometric information that can be used for personal authentication include fingerprints, palm prints, veins, irises, etc. These biometric information can be acquired using visible light or infrared light. In particular, information on veins and irises is preferably acquired using infrared light.

[0300] Among the biological information that can be acquired using the display device of one embodiment of the present invention, examples of biological information that can be used for healthcare purposes include pulse waves, blood glucose levels, oxygen saturation levels, and triglyceride concentrations.

[0301] Furthermore, it is preferable to provide an electronic device equipped with a display device with means for acquiring other biological information. For example, this includes internal biological information such as electrocardiogram, blood pressure, and body temperature, as well as superficial biological information such as facial expression, complexion, and pupils. Information on the number of steps taken, exercise intensity, elevation change, and diet (calorie intake, nutrients, etc.) is also important for health care. Using multiple pieces of biological information enables comprehensive health management, which not only contributes to daily health management but also to the early detection of injuries and illnesses.

[0302] For example, blood pressure can be calculated from an electrocardiogram and the difference in timing between two pulses of a pulse wave (length of pulse wave propagation time). High blood pressure results in a short pulse wave propagation time, and conversely, low blood pressure results in a long pulse wave propagation time. The user's physical condition can also be estimated from the relationship between heart rate and blood pressure calculated from an electrocardiogram and pulse wave. For example, if both the heart rate and blood pressure are high, it can be estimated that the user is in a state of tension or excitement, and conversely, if both the heart rate and blood pressure are low, it can be estimated that the user is in a relaxed state. Furthermore, if the user has low blood pressure and a high heart rate that continues to be present, it could be a sign of heart disease or the like.

[0303] Users can check their own physical condition at any time, either based on biometric information measured by electronic devices or estimated based on that information, which will improve their health awareness. This may encourage them to review their daily habits, such as avoiding overeating, getting moderate exercise, and managing their health, and may also encourage them to seek medical attention if necessary.

[0304] [Configuration example 1] FIG. 11A shows a schematic diagram of electronic device 80. Electronic device 80 can be used as a smartphone. Electronic device 80 includes at least a housing 82, a display unit 81a, and a display unit 81b. Display unit 81a functions as a primary display surface, and display unit 81b functions as a secondary display surface, and both have a curved surface shape that conforms to the side surface of housing 82. Display units 81a and 81b are formed by applying a display device according to one embodiment of the present invention.

[0305] As shown in FIG. 11A, display unit 81b is provided in a position where finger 60 naturally touches electronic device 80 when the user holds electronic device 80 in hand 60a. At this time, electronic device 80 can acquire the fingerprint of finger 60 touching display unit 81b and perform fingerprint authentication. This allows authentication to be performed simultaneously with the action of holding electronic device 80, without the user being aware of it. Therefore, by the time the user picks up electronic device 80 and looks at the screen, authentication has already been completed and the device is logged in, making it ready for immediate use, thereby providing an electronic device that combines high security with high convenience.

[0306] 11B, when a finger 60 touches the display unit 81a, biometric information of the user can be obtained from the finger 60. For example, it is possible to capture images of the shape of veins and arterioles, and it is possible to obtain various types of biometric information such as pulse rate or oxygen concentration from the captured information.

[0307] As shown in FIG. 11C, similar biometric information can also be obtained on the display section 81b by touching the display section 81b with a finger 60.

[0308] The biometric information can be acquired, for example, by the user executing an application for acquiring and managing the biometric information. The application enables the electronic device 80 to recognize that the finger 60 is touching the display unit 81a or the display unit 81b and to perform an image capture. Furthermore, the biometric information described above can be acquired from the captured image, and data can be stored or managed.

[0309] 12 includes a display unit 81c in addition to the display units 81a and 81b. The display unit 81c is located on the opposite side of the display unit 81a from the display unit 81b.

[0310] As shown in Fig. 12, display unit 81c is provided at a position where one or more of the index finger, middle finger, ring finger, and little finger of the five fingers 60 of a user holding electronic device 80a with hand 60a can naturally touch. Display unit 81b is provided at a position where the thumb can naturally touch. Display unit 81b and display unit 81c can each capture fingerprint images. This allows fingerprint authentication to be performed using fingerprints from multiple fingertips, which is preferable because it allows for more accurate authentication.

[0311] Furthermore, the electronic device 80a has a symmetrical configuration, so it can be used with either the right or left hand, which is preferable.

[0312] [Configuration example 2] 13 is a schematic diagram of an electronic device 80b. The electronic device 80b can be used as a tablet terminal. The electronic device 80b includes at least a housing 82, a display portion 81a, and a display portion 81b. The display device of one embodiment of the present invention is used for the display portion 81a and the display portion 81b.

[0313] When the user holds his / her hand 60a over or touches the display unit 81, the electronic device 80b can perform personal authentication and acquire biometric information of the user.

[0314] When the user places the hand 60a on the display unit 81, the electronic device 80b can recognize the shape of the hand. Then, biometric information appropriate for each region corresponding to each part of the hand 60a is acquired. For example, in the region 85a corresponding to the fingertips of the hand 60a, it is possible to acquire images of the fingerprint shape and vein shape. In the region 85b corresponding to the finger pads, it is possible to acquire images of the vein shape and arterioles. In the region 85c corresponding to the palm, it is possible to acquire images of the palm print, veins, arterioles, and dermis. Images of the fingerprint, palm print, and veins can be used for personal authentication. Images of the arterioles, veins, or dermis can be used to acquire biometric information.

[0315] Furthermore, when acquiring biometric information, an image of a hand shape may be displayed on the display unit 81, and the user may be prompted to place their hand 60a in line with the image. This can improve the accuracy of recognizing the shape of the hand 60a.

[0316] In this way, the user's biometric information can be acquired each time personal authentication is performed to start up the electronic device 80b. This allows biometric information to be continuously accumulated without the user being aware of it, allowing for continuous health management. This is also preferable because it eliminates the need for the user to run health management application software each time, eliminating the risk of interruptions in the acquisition and updating of biometric information.

[0317] [System configuration example] According to one aspect of the present invention, various types of biometric information can be acquired periodically and continuously, and this biometric information can be used for personal authentication, health management, and the like.

[0318] For example, biometric information obtained using visible light and infrared light includes fingerprints, palm prints, vein patterns, pulse waves, respiratory rates, pulse rates, oxygen saturation levels, blood sugar levels, and triglyceride concentrations. Other examples include facial expressions, complexions, pupils, and voiceprints. Using such various types of biometric information is preferable because it allows for a comprehensive assessment of the user's health condition.

[0319] A typical method of personal authentication using biometric information is the pattern matching method. For example, from images of fingerprints, palm prints, vein patterns, etc., feature quantities such as the coordinates of multiple characteristic points and the vectors between these coordinates are calculated, and authentication can be performed by comparing them with pre-acquired feature quantities of the user. Using images of two or more of fingerprints, palm prints, and vein patterns allows for highly accurate authentication.

[0320] Furthermore, machine learning may be used for personal authentication using biometric information or for determining health status. The learning model used for machine learning may be a pre-trained learning model, or a learning model updated using acquired user data. Machine learning techniques include, for example, supervised machine learning and unsupervised machine learning.

[0321] An example of the configuration and operation of a system according to one embodiment of the present invention will be described below with reference to the drawings.

[0322] 14 shows a block diagram of a system 90 including a display device according to one embodiment of the present invention. The system 90 includes a calculation unit 91, a storage unit 92, an input unit 93, an output unit 94, and a bus line 95. The system 90 can be applied to various electronic devices having a display unit, such as the electronic device 80 described above.

[0323] The calculation unit 91 is connected to a storage unit 92, an input unit 93, an output unit 94, etc. via a bus line 95, and has the function of controlling these units in an integrated manner.

[0324] The memory unit 92 has a function of storing data, programs, etc. The calculation unit 91 can control various components included in the input unit 93 and output unit 94 by reading out programs or data from the memory unit 92 and executing or processing them.

[0325] Various sensor devices can be used as the input unit 93. Here, components included in the input unit 93 include an optical sensor 93a, a camera 93b, a microphone 93c, and an electrocardiogram monitor 93d. The optical sensor 93a can be a sensor using a light-receiving element included in the display device. The electrocardiogram monitor 93d may include, for example, a pair of electrodes for measuring an electrocardiogram and a measuring device for measuring the voltage between the electrodes or the value of the current flowing between the electrodes.

[0326] The output unit 94 has a function of providing various information to the user. In this example, the output unit 94 includes components such as a display 94a, a speaker 94b, and a vibration device 94c.

[0327] 14 。 In other words, the display device of one embodiment of the present invention can be realized by a configuration including the display device, a calculation unit 91, and a storage unit 92.

[0328] For example, the display device has a function of acquiring biometric information such as a user's fingerprint, palm print, or vein pattern, and the calculation unit 91 can perform fingerprint authentication, palm print authentication, or vein authentication based on the acquired biometric information and the user's biometric data pre-stored in the memory unit 92.

[0329] An example of how the system according to one aspect of the present invention operates will now be described, focusing on the operation of performing biometric authentication.

[0330] Fig. 15 is a flowchart showing the operation method of the system. The flowchart shown in Fig. 15 includes steps S0 to S8.

[0331] In step S0, the operation starts.

[0332] In step S1, it is determined whether or not to start up the system. For example, it is determined to start up the system when it detects that the electronic device is turned on, that the display unit is touched, or that the position of the electronic device has changed. On the other hand, if these events are not detected, it proceeds to step S8 and ends the operation.

[0333] In step S2, it is determined whether authentication is required. If authentication has already been performed and the system is in a logged-in state, it is determined that authentication is not required and the process proceeds to step S7. On the other hand, if the system is in a logged-off state, it is determined that authentication is required and the process proceeds to step S3.

[0334] In step S3, it is determined whether an authentication operation has been detected. For example, if it is detected that the user's finger or palm has touched part of the display unit, it is determined that an authentication operation has been detected, and the process proceeds to step S4. On the other hand, if no detection has been made for a certain period of time, the process proceeds to step S8, where the operation ends.

[0335] In step S4, authentication information is acquired. For example, an image of the user's fingerprint, palm print, veins, etc. is captured, and biometric information is acquired from the captured image.

[0336] In step S5, it is determined whether authentication has been performed correctly. For example, the fingerprint, palm print, or vein information acquired in step S4 is compared with the user's pre-registered biometric information to determine whether they match. This determination can be made using an authentication method such as a pattern matching method that does not use a machine learning model, or authentication that uses a machine learning model. If authentication has been performed correctly, the process proceeds to step S6. If authentication has not been performed correctly, the logged-off state is maintained and the process returns to step S4.

[0337] In step S6, system login is performed.

[0338] In step S7, the logged-in state is maintained. Step S7 ends when the user performs an end operation or when it is detected that no input has been made for a certain period of time, and the process proceeds to step S8.

[0339] In step S8, the operation is terminated. Step S8 is at least a logged-off state. It may also be a power-off state, a standby state, or a sleep state. Return from step S8 may be performed by the operation detected in step S1 above.

[0340] 11A or 12, the detection of the authentication operation in step S3 and the acquisition of authentication information in step S4 can be performed by touching the fingertip to the display unit 81b or 81c, as shown in Fig. 11A and 12. The biometric information acquired in step S4 can be an image of a fingerprint or the like obtained by capturing an image of light reflected by the fingertip using a light receiving element in the display unit 81b or 81c.

[0341] That is, in an electronic device of one embodiment of the present invention (e.g., electronic device 80 or electronic device 80a), when a user's finger touches display unit 81b or 81c, calculation unit 91 can perform fingerprint authentication operation using a fingerprint image obtained by capturing light reflected by the finger using a light receiving element included in display unit 81b or 81c. This allows the authentication operation to be performed without the user's knowledge, thereby realizing an electronic device that is both convenient and highly secure.

[0342] The above is a description of an example of the configuration and operation of a system according to one aspect of the present invention.

[0343] (Embodiment 3) In this embodiment, a structure of a pixel that can be applied to a display device of one embodiment of the present invention will be described with reference to drawings.

[0344] A display panel according to one embodiment of the present invention includes a first pixel circuit having a light-receiving element and a second pixel circuit having a light-emitting element, and the first pixel circuit and the second pixel circuit are arranged in a matrix.

[0345] FIG. 16A shows an example of a first pixel circuit having a light receiving element, and FIG. 16B shows an example of a second pixel circuit having a light emitting element.

[0346] 16A includes a light receiving element PD, a transistor M1, a transistor M2, a transistor M3, a transistor M4, and a capacitance element C1. Here, an example is shown in which a photodiode is used as the light receiving element PD.

[0347] The cathode of the light-receiving element PD is electrically connected to the wiring V1, and the anode is electrically connected to one of the source and drain of the transistor M1. The gate of the transistor M1 is electrically connected to the wiring TX, and the other of the source and drain is electrically connected to one electrode of the capacitor C1, one of the source and drain of the transistor M2, and the gate of the transistor M3. The gate of the transistor M2 is electrically connected to the wiring RES, and the other of the source and drain is electrically connected to the wiring V2. The source and drain of the transistor M3 is electrically connected to the wiring V3, and the other of the source and drain is electrically connected to one of the source and drain of the transistor M4. The gate of the transistor M4 is electrically connected to the wiring SE, and the other of the source and drain is electrically connected to the wiring OUT1.

[0348] A constant potential is supplied to the wiring V1, wiring V2, and wiring V3. When the light-receiving element PD is driven with a reverse bias, a potential lower than the potential of the wiring V1 is supplied to the wiring V2. The transistor M2 is controlled by a signal supplied to the wiring RES and has the function of resetting the potential of the node connected to the gate of the transistor M3 to the potential supplied to the wiring V2. The transistor M1 is controlled by a signal supplied to the wiring TX and has the function of controlling the timing at which the potential of the node changes depending on the current flowing through the light-receiving element PD. The transistor M3 functions as an amplifying transistor that outputs according to the potential of the node. The transistor M4 is controlled by a signal supplied to the wiring SE and functions as a selection transistor that reads the output according to the potential of the node to an external circuit connected to the wiring OUT1.

[0349] 16B includes a light-emitting element EL, transistors M5, M6, and M7, and a capacitor C2. Here, an example is shown in which a light-emitting diode is used as the light-emitting element EL. In particular, it is preferable to use an organic EL element as the light-emitting element EL.

[0350] The transistor M5 has a gate electrically connected to the wiring VG, one of its source or drain electrically connected to the wiring VS, and the other of its source or drain electrically connected to one electrode of the capacitor C2 and the gate of the transistor M6. One of the source or drain of the transistor M6 is electrically connected to the wiring V4, and the other is electrically connected to the anode of the light-emitting element EL and one of the source or drain of the transistor M7. The transistor M7 has a gate electrically connected to the wiring MS, and the other of its source or drain electrically connected to the wiring OUT2. The cathode of the light-emitting element EL is electrically connected to the wiring V5.

[0351] A constant potential is supplied to the wiring V4 and the wiring V5. The anode side of the light-emitting element EL can be set to a high potential, and the cathode side can be set to a lower potential than the anode side. The transistor M5 is controlled by a signal supplied to the wiring VG and functions as a selection transistor for controlling the selection state of the pixel circuit PIX2. The transistor M6 also functions as a drive transistor that controls the current flowing through the light-emitting element EL depending on the potential supplied to its gate. When the transistor M5 is in a conductive state, the potential supplied to the wiring VS is supplied to the gate of the transistor M6, and the light emission brightness of the light-emitting element EL can be controlled depending on the potential. The transistor M7 is controlled by a signal supplied to the wiring MS and has the function of outputting the potential between the transistor M6 and the light-emitting element EL to the outside via the wiring OUT2.

[0352] In the display panel of this embodiment, an image may be displayed by pulsating the light-emitting elements. By shortening the driving time of the light-emitting elements, it is possible to reduce the power consumption and heat generation of the display panel. In particular, organic EL elements are suitable because of their excellent frequency characteristics. The frequency can be, for example, 1 kHz or more and 100 MHz or less.

[0353] Here, it is preferable that the transistors M1, M2, M3, and M4 in the pixel circuit PIX1, and the transistors M5, M6, and M7 in the pixel circuit PIX2 are transistors that use a metal oxide (oxide semiconductor) in the semiconductor layer in which the channel is formed.

[0354] A transistor using a metal oxide, which has a wider band gap and a lower carrier density than silicon, can achieve an extremely small off-state current. Therefore, the small off-state current allows the charge stored in the capacitor connected in series with the transistor to be held for a long period of time. Therefore, it is preferable to use transistors including an oxide semiconductor for the transistor M1, the transistor M2, and the transistor M5, which are connected in series with the capacitor C1 or the capacitor C2. Furthermore, by using transistors including an oxide semiconductor for other transistors as well, manufacturing costs can be reduced.

[0355] Alternatively, the transistors M1 to M7 may be transistors in which silicon is used as a semiconductor in which a channel is formed. In particular, using silicon with high crystallinity, such as single crystal silicon or polycrystalline silicon, is preferable because high field-effect mobility can be achieved and higher-speed operation is possible.

[0356] Alternatively, a structure may be used in which at least one of the transistors M1 to M7 includes an oxide semiconductor and the remaining transistors include silicon.

[0357] Although the transistors are shown as n-channel transistors in FIGS. 16A and 16B, p-channel transistors can also be used.

[0358] The transistors of the pixel circuit PIX1 and the transistors of the pixel circuit PIX2 are preferably formed side by side on the same substrate. In particular, it is preferable that the transistors of the pixel circuit PIX1 and the transistors of the pixel circuit PIX2 are mixed and periodically arranged in one region.

[0359] It is also preferable to provide one or more layers having a transistor and / or a capacitor at a position overlapping the light receiving element PD or the light emitting element EL, thereby reducing the effective area occupied by each pixel circuit and realizing a high-definition light receiving section or display section.

[0360] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0361] (Fourth embodiment) In this embodiment, electronic devices to which the display device of one embodiment of the present invention can be applied will be described with reference to drawings.

[0362] The electronic device of this embodiment includes the display device of one embodiment of the present invention. The display device has a function of detecting light, and therefore, biometric authentication can be performed in the display portion, and touch or near-touch can be detected. The electronic device of one embodiment of the present invention is difficult to be illegally used and has an extremely high level of security. Furthermore, the functionality, convenience, and the like of the electronic device can be improved.

[0363] Examples of electronic devices include electronic devices with relatively large screens such as television sets, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and sound playback devices.

[0364] The electronic device of this embodiment may have a sensor (including the function of sensing, detecting, or measuring force, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared light).

[0365] The electronic device of the present embodiment can have various functions, such as a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, time, etc., a function to execute various software (programs), a wireless communication function, a function to read out programs or data recorded on a recording medium, etc.

[0366] Electronic device 6500 shown in FIG. 17A is a portable information terminal that can be used as a smartphone.

[0367] The electronic device 6500 includes a housing 6501, a display portion 6502, a power button 6503, a button 6504, a speaker 6505, a microphone 6506, a camera 6507, and a light source 6508. The display portion 6502 has a touch panel function.

[0368] The display device of one embodiment of the present invention can be applied to the display portion 6502.

[0369] FIG. 17B is a schematic cross-sectional view including the end of the housing 6501 on the microphone 6506 side.

[0370] A light-transmitting protective member 6510 is provided on the display surface side of the housing 6501, and a display panel 6511, optical members 6512, a touch sensor panel 6513, a printed circuit board 6517, a battery 6518, etc. are arranged in the space surrounded by the housing 6501 and the protective member 6510.

[0371] A display panel 6511, an optical member 6512, and a touch sensor panel 6513 are fixed to the protective member 6510 by adhesive layers (not shown).

[0372] In an area outside the display unit 6502, a part of the display panel 6511 is folded back, and an FPC 6515 is connected to the folded back part. An IC 6516 is mounted on the FPC 6515. The FPC 6515 is connected to a terminal provided on a printed circuit board 6517.

[0373] The flexible display of one embodiment of the present invention can be applied to the display panel 6511. Therefore, an extremely lightweight electronic device can be realized. In addition, since the display panel 6511 is extremely thin, a large-capacity battery 6518 can be mounted thereon while keeping the thickness of the electronic device small. Furthermore, by folding back a part of the display panel 6511 and arranging a connection portion with the FPC 6515 on the back side of the pixel portion, an electronic device with a narrow frame can be realized.

[0374] 18A shows an example of a television device. A television device 7100 has a display unit 7000 built into a housing 7101. Here, the housing 7101 is supported by a stand 7103.

[0375] The display device of one embodiment of the present invention can be applied to the display portion 7000.

[0376] 18A can be operated using an operation switch provided on the housing 7101 or a separate remote control 7111. Alternatively, a touch sensor may be provided in the display unit 7000, and the television unit 7100 may be operated by touching the display unit 7000 with a finger or the like. The remote control 7111 may have a display unit that displays information output from the remote control 7111. Using the operation keys or touch panel provided on the remote control 7111, the channel and volume can be controlled, and the video displayed on the display unit 7000 can be operated.

[0377] The television device 7100 is configured to include a receiver, a modem, and the like. The receiver can receive general television broadcasts. In addition, by connecting to a wired or wireless communication network via the modem, it is possible to perform one-way (from sender to receiver) or two-way (between sender and receiver, or between receivers, etc.) information communication.

[0378] 18B shows an example of a laptop personal computer 7200. The laptop personal computer 7200 includes a housing 7211, a keyboard 7212, a pointing device 7213, an external connection port 7214, and the like. A display portion 7000 is incorporated in the housing 7211.

[0379] The display device of one embodiment of the present invention can be applied to the display portion 7000.

[0380] 18C and 18D show an example of digital signage.

[0381] 18C includes a housing 7301, a display unit 7000, and a speaker 7303. The digital signage 7300 may further include an LED lamp, operation keys (including a power switch or an operation switch), a connection terminal, various sensors, a microphone, and the like.

[0382] 18D shows a digital signage 7400 attached to a cylindrical pillar 7401. The digital signage 7400 has a display unit 7000 provided along the curved surface of the pillar 7401.

[0383] 18C and 18D, the display device of one embodiment of the present invention can be applied to the display portion 7000.

[0384] The larger the display unit 7000, the more information can be provided at one time. Also, the larger the display unit 7000, the more easily it will attract people's attention, which can increase the advertising effectiveness of, for example, advertisements.

[0385] Applying a touch panel to the display unit 7000 is preferable because it not only displays images or videos on the display unit 7000 but also allows the user to intuitively operate it. Furthermore, when used to provide information such as route information or traffic information, intuitive operation can improve usability.

[0386] 18C and 18D, it is preferable that the digital signage 7300 or the digital signage 7400 can be linked via wireless communication with an information terminal 7311 or an information terminal 7411 such as a smartphone carried by a user. For example, advertising information displayed on the display unit 7000 can be displayed on the screen of the information terminal 7311 or the information terminal 7411. Furthermore, the display on the display unit 7000 can be switched by operating the information terminal 7311 or the information terminal 7411.

[0387] Furthermore, it is also possible to run a game on the digital signage 7300 or the digital signage 7400 using the screen of the information terminal 7311 or the information terminal 7411 as an operation means (controller), thereby allowing an unspecified number of users to simultaneously participate in and enjoy the game.

[0388] The electronic device shown in Figures 19A to 19F has a housing 9000, a display unit 9001, a speaker 9003, operation keys 9005 (including a power switch or an operation switch), a connection terminal 9006, a sensor 9007 (including the function of detecting, detecting, or measuring force, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays), a microphone 9008, etc.

[0389] 19A to 19F have various functions. For example, they may have a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, or time, a function to control processing using various software (programs), a wireless communication function, a function to read and process programs or data recorded on a recording medium, etc. Note that the functions of the electronic device are not limited to these, and the electronic device may have various other functions. The electronic device may have multiple display units. Furthermore, the electronic device may have a function to include a camera or the like to capture still images or videos and store them on a recording medium (external or built-in to the camera), a function to display the captured images on the display unit, etc.

[0390] The electronic device shown in FIGS. 19A to 19F will be described in detail below.

[0391] FIG. 19A is a perspective view showing a mobile information terminal 9101. The mobile information terminal 9101 can be used as, for example, a smartphone. The mobile information terminal 9101 may be provided with a speaker 9003, a connection terminal 9006, a sensor 9007, and the like. The mobile information terminal 9101 can display text or image information on multiple surfaces. FIG. 19A shows an example in which three icons 9050 are displayed. Information 9051, indicated by a dashed rectangle, can also be displayed on another surface of the display unit 9001. Examples of the information 9051 include notifications of incoming emails, SNS messages, phone calls, etc., the title of the email or SNS message, the sender's name, the date and time, the remaining battery level, and the strength of antenna reception. Alternatively, the icon 9050 or the like may be displayed in the position where the information 9051 is displayed.

[0392] 19B is a perspective view showing a mobile information terminal 9102. The mobile information terminal 9102 has a function of displaying information on three or more sides of the display unit 9001. Here, an example is shown in which information 9052, information 9053, and information 9054 are displayed on different sides. For example, while the user holds the mobile information terminal 9102 in a breast pocket of their clothes, the user can check information 9053 displayed in a position that can be observed from above the mobile information terminal 9102. The user can check the display without taking the mobile information terminal 9102 out of their pocket and decide, for example, whether to answer a call.

[0393] 19C is a perspective view showing a wristwatch-type mobile information terminal 9200. The display surface of the display unit 9001 is curved, and a display can be displayed along the curved display surface. The mobile information terminal 9200 can also perform hands-free conversations by communicating with, for example, a headset capable of wireless communication. The mobile information terminal 9200 can also perform data transmission and reception with another information terminal or charge itself via a connection terminal 9006. Note that charging may be performed by wireless power supply.

[0394] 19D, 19E, and 19F are perspective views showing a foldable mobile information terminal 9201. FIG. 19D shows the mobile information terminal 9201 in an unfolded state, FIG. 19F shows it in a folded state, and FIG. 19E is a perspective view showing a state in the process of changing from one of FIG. 19D and FIG. 19F to the other. The mobile information terminal 9201 is highly portable when folded, and has a seamless, wide display area when unfolded, providing excellent viewability of the display. A display unit 9001 of the mobile information terminal 9201 is supported by three housings 9000 connected by hinges 9055. For example, the display unit 9001 can be bent with a curvature radius of 0.1 mm or more and 150 mm or less.

[0395] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification. [Example]

[0396] In this example, a display device according to one embodiment of the present invention was manufactured, and the results of imaging veins will be described.

[0397] [Photodetector] The characteristics of the fabricated photodetector are shown in Figure 20. In Figure 20, the vertical axis represents external quantum efficiency (EQE [%]) and the horizontal axis represents wavelength (Wavelength [nm]). As shown in Figure 20, it was confirmed that the fabricated photodetector exhibits high sensitivity from ultraviolet light to infrared light (400nm-900nm).

[0398] [Light-emitting element] FIG. 21A shows a schematic diagram of a light-emitting element that emits infrared light and is used in a display device. Two types of light-emitting elements were fabricated here. One is a light-emitting element (labeled Ref.) that has one light-emitting unit between an anode and a cathode, as shown on the left side of FIG. 21A. The other is a light-emitting element (labeled Sample 1) that has two light-emitting units stacked between an anode and a cathode, as shown on the right side of FIG. 21A. The one light-emitting unit in Ref. and the two light-emitting units in Sample 1 each have the same configuration, and each has a light-emitting layer containing a light-emitting material that emits infrared light.

[0399] Figure 21B shows the emission spectra of the two types of light-emitting devices fabricated. In Figure 21B, the vertical axis represents normalized emission intensity (Intensity [au]) and the horizontal axis represents wavelength (Wavelength [nm]). As shown in Figure 21B, it was found that both types of light-emitting devices emit light in the wavelength range of 700 nm to 950 nm, and have a peak at a wavelength of around 800 nm. Furthermore, there was almost no difference in the shape of the spectra between the two types of light-emitting devices.

[0400] FIG. 22A shows the measurement results of the external quantum efficiency-current density characteristics of the two types of light-emitting devices, and FIG. 22B shows the measurement results of the current density-voltage characteristics.

[0401] In FIG. 22A, the vertical axis represents the external quantum efficiency, and the horizontal axis represents the current density (mA / cm 2 ]). In FIG. 22B, the vertical axis represents current density, and the horizontal axis represents voltage (Voltage [V]). As shown in FIGS. 22A and 22B, Sample 1, which has a stacked structure, has a higher driving voltage than Ref., but the external quantum efficiency is increased, reaching a value approximately twice as high.

[0402] [Image results] A display panel was fabricated using the above-described light-emitting element and light-receiving element. The configuration of the display panel can be the same as that of the display device 100B (FIG. 4B) illustrated in Embodiment 1. The above-described light-receiving element was used as the light-receiving element 110 in the display device 100B, and either Ref. or Sample 1 was used as the light-emitting element 160. The light-emitting element that emits infrared light was a bottom-emission type light-emitting element, and of the pair of electrodes, the electrode on the formation surface side (display surface side) (electrode 161 in FIG. 4B) was used as the cathode, and the other electrode (electrode 163t) was used as the anode.

[0403] First, as shown in FIG. 23A, an image was taken in a state where a light emitting element that emits infrared light, which the display panel has, was turned on.

[0404] Figure 23B shows the imaging results when the Ref. element is used as the light-emitting element that emits infrared light. The dashed line in Figure 23B schematically shows the outline of the finger. As shown in Figure 23B, although the contrast is low, it is clear that the shape of the blood vessels in the finger can be recognized.

[0405] 23C shows the imaging results when Sample 1 element is used as a light-emitting element that emits infrared light. When Sample 1 element with a layered structure is used, it can be seen that the shape of blood vessels can be clearly confirmed.

[0406] 23D, an image was taken with a light-emitting diode (LED) emitting infrared light with a wavelength of 850 nm from above the finger, while the light-emitting element on the display panel that emits the infrared light was turned off.

[0407] The imaging results are shown in Figure 23E. As shown above, it was confirmed that the shape of blood vessels can be clearly imaged not only when using reflected light but also when using transmitted light. [Explanation of symbols]

[0408]

Claims

[Claim 1] a first light-emitting element, a second light-emitting element, a light-receiving element, and a light-shielding layer; the first light-emitting element and the light-receiving element are arranged side by side on the same plane, the light-shielding layer is provided above the first light-emitting element and the light-receiving element, the second light-emitting element is provided above the light-shielding layer, the first light-emitting element has a function of emitting visible light upward, the second light-emitting element has a function of emitting invisible light upward, the light receiving element is a photoelectric conversion element sensitive to the visible light and the invisible light, In plan view, the light-shielding layer has a portion located between the first light-emitting element and the light-receiving element, the second light-emitting element overlaps the light-shielding layer and is located inside the outline of the light-shielding layer; Display device.

Images