Light emitting device, display, imaging apparatus, and electronic apparatus

Abstract

To provide a light emitting device that can reduce a reduction in display quality due to reflection of light from a display on an infrared light emitting unit.SOLUTION: A light emitting device has, on a substrate, a first light emitting element emitting visible light and a second light emitting element emitting infrared light. The first light emitting element has a first luminous layer and a first reflecting layer between the substrate and the first luminous layer. The second light emitting element has a second luminous layer and a second reflecting layer between the substrate and the second luminous layer. The average reflectance for the visible light on the second reflecting layer is smaller than the average reflectance for the visible light on the first reflecting layer.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a light-emitting device, a display device, an imaging device, and an electronic device. [Background technology]

[0002] An organic light-emitting device is a device that emits light by applying a voltage to a light-emitting layer that has an organic compound layer. Because organic light-emitting devices are self-emitting devices, they do not require a separate light source and display control such as a shutter, as is the case with liquid crystal display devices. This has the advantage of enabling them to be thinner and consume less power than liquid crystal display devices. For this reason, they have attracted attention as image display devices for camera viewfinders, head-mounted displays, wearable devices known as smart glasses, and other applications.

[0003] Among such display devices, there are some that detect the user's line of sight toward the display device, thereby detecting the user's gaze point, and reflect the detected gaze information in driving the display device. Patent Document 1 discloses a device that detects the gaze by irradiating infrared light onto the eyeball of a user looking into a viewfinder and capturing the light reflected from the eyeball with a detector. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-15731 Summary of the Invention [Problem to be solved by the invention]

[0005] In the display device of Patent Document 1, light from the display unit of the viewfinder enters the infrared light-emitting unit, and the visibility of the display unit may be reduced by the light reflected from the infrared light-emitting unit. The present invention has been made in consideration of the above-mentioned problem, and its purpose is to provide a light-emitting device that can reduce the degradation of display quality caused by light from the display unit being reflected by the infrared light-emitting unit. [Means for solving the problem]

[0006] One embodiment of the light-emitting device is a light-emitting device having a first light-emitting element that emits visible light and a second light-emitting element that emits infrared light on a substrate, wherein the first light-emitting element has a first light-emitting layer and a first reflective layer between the substrate and the first light-emitting layer, and the second light-emitting element has a second light-emitting layer and a second reflective layer between the substrate and the second light-emitting layer, and the average reflectance of the second reflective layer for visible light is smaller than the average reflectance of the first reflective layer for visible light. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a light emitting device that can reduce degradation of display quality caused by light from a display section being reflected by an infrared light emitting section. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram illustrating an example of a light-emitting device according to an embodiment of the present invention. [Figure 2] 1 is a plan view illustrating an example of a light emitting device according to an embodiment of the present invention. [Figure 3] 1 is a cross-sectional view illustrating an example of a light-emitting device according to an embodiment of the present invention. [Figure 4] 1 is a cross-sectional view illustrating an example of a light-emitting device according to an embodiment of the present invention. [Figure 5] 1 is a cross-sectional view illustrating an example of a light-emitting device according to an embodiment of the present invention. [Figure 6] FIG. 10 is a diagram illustrating an example of reflectance according to an embodiment of the present invention. [Figure 7] 1 is a cross-sectional view illustrating an example of a light-emitting device according to an embodiment of the present invention. [Figure 8] 1 is a cross-sectional view illustrating an example of a light-emitting device according to an embodiment of the present invention. [Figure 9] 1 is a cross-sectional view illustrating an example of a light-emitting device according to an embodiment of the present invention. [Figure 10]1 is a cross-sectional view illustrating an example of a light-emitting device according to an embodiment of the present invention. [Figure 11] 1 is a cross-sectional view illustrating an example of a light-emitting device according to an embodiment of the present invention. [Figure 12] 1 is a schematic diagram illustrating an example of a display device according to an embodiment of the present invention. [Figure 13] 1A is a schematic diagram showing an example of an imaging device according to an embodiment of the present invention; FIG. 1B is a schematic diagram showing an example of an electronic device according to an embodiment of the present invention; [Figure 14] 1A and 1B are schematic diagrams showing an example of a wearable device according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0010] FIG. 1 is a schematic diagram showing the configuration and line-of-sight detection operation of a display device according to one embodiment of the present invention. In the display device 1, a display unit 3 and an infrared light emitter 4 are arranged on an insulating layer 2 provided on a substrate. The display unit forms a display image by emitting display light 7. Meanwhile, the infrared light emitter 4 emits infrared light 8 toward the eyeball 6 of a user gazing at the display image. An imaging unit 5 having a light receiving element detects the reflected light of the emitted infrared light 8 from the eyeball, thereby obtaining an image of the eyeball.

[0011] The gaze detection can be performed by detecting the user's gaze toward the displayed image from an image of the eyeball captured using infrared light. Any known method can be used for gaze detection using an image of the eyeball. One example is a gaze detection method based on the Purkinje image formed by the reflection of irradiated light on the cornea.

[0012] More specifically, gaze detection processing is performed based on the pupil-corneal reflex method. Using the pupil-corneal reflex method, a gaze vector representing the direction (rotation angle) of the eyeball is calculated based on the pupil image and Purkinje image included in the captured image of the eyeball 6, thereby detecting the user's gaze.

[0013] At this time, light from the display unit is incident on the infrared light-emitting unit for line-of-sight detection, and reflected light is emitted. The path along which light from the display unit is incident on the infrared light-emitting unit is, for example, the path along which light from the display unit is reflected by the eyeball and incident on the infrared region.

[0014] (First embodiment) Next, a detailed description will be given of an example of the configuration of the display element and the infrared light-emitting element in the display device according to this embodiment. Reflected light emitted when light from the display unit enters the infrared light-emitting unit for line-of-sight detection according to this embodiment can be reduced by setting the reflectance in the visible light region of the lower reflective layer of the infrared light-emitting unit lower than the reflectance in the visible light region of the lower reflective layer of the display unit that emits visible light.

[0015] FIG. 2 is a plan view schematic diagram of a display device according to this embodiment, in which a display section 3 and an infrared light-emitting section 4 are disposed on an insulating layer 2 to form a display region 9. The display section 3 has a display element capable of emitting visible light. In this specification, a display element is also referred to as a light-emitting element, since it emits visible light. The display section may have an organic light-emitting element having, in this order from an insulating layer, a first electrode, an organic compound layer including a light-emitting layer, and a second electrode. The light emitted from the display section may be of any color, and may emit white light. Furthermore, each light-emitting pixel may emit a different color. The region in which the display section 3 is disposed is a first light-emitting region that emits visible light.

[0016] The infrared light-emitting unit 4 is not particularly limited in type as long as it has an infrared light-emitting element capable of emitting infrared light, and may be, for example, an organic light-emitting element, an LED element, or a light-emitting element containing a perovskite material or a quantum dot (QD) material. The region in which the infrared light-emitting unit 4 is arranged is referred to as the second light-emitting region. If the infrared light-emitting element is an organic light-emitting element, this is convenient because the organic light-emitting element and the infrared light-emitting element can be manufactured using the same process. If the infrared light-emitting element is an organic light-emitting element, it may have, similar to the display unit 3, a first electrode, an organic compound layer including a light-emitting layer, and a second electrode, in this order from the insulating layer.

[0017] The imaging unit 5 having a light receiving element may have an imaging element sensitive to the infrared region, such as a photodiode, an organic photoelectric conversion element, or an inorganic photoelectric conversion element. The imaging unit may be formed on the same substrate 2 as the display unit 3 and the infrared light emitting unit 4, or may be formed on a different substrate and be a separate member. In order to reduce false detection due to the incidence of visible light, an infrared filter that transmits only infrared light may be provided on the imaging element.

[0018] FIG. 3 shows an example of the configuration of an image observation device according to this embodiment. The device is configured with a display device 1 and a display lens 21 as an eyepiece optical system, and display light 7 is projected onto the user's eyeball 6, allowing the observer to observe the displayed image. Furthermore, infrared light reflected by the user's eyeball 6 is converted into electrical information by the imaging unit 5, and the line of sight can be detected based on this information. In another example configuration, as shown in FIG. 4, the display light 7 and infrared light 8 from the display device 1 may reach the user's eyeball 6 through the same display lens 21.

[0019] Fig. 5 is a cross-sectional schematic diagram taken along the line A-A' in Fig. 2. The light-emitting element 100 in Fig. 5 is configured, in this order, on an insulating layer 2, with a lower reflective layer 11A, a functional layer 12 including a light-emitting layer, an upper electrode 13, and a protective layer 14. Here, the lower reflective layer 11A can function as a lower electrode. Furthermore, as shown in Fig. 5, an insulating layer 15 is provided to cover both ends of the lower reflective layer 11A. The insulating layer 15 is also called a pixel separation film or a bank.

[0020] The functional layer may be in contact with a portion of the lower reflective layer that is not in contact with the insulating layer. The region where the lower reflective layer and the functional layer are in contact is the light-emitting region 16 that emits light when an electric field is applied between the lower reflective layer and the upper electrode. The light-emitting region may be identified by measuring the distance from the edge of the first insulating layer 15 covering the left edge of one lower reflective layer 11A in FIG. 5 to the edge of the second insulating layer 15 covering the right edge of the lower reflective layer 11A. The edge of the insulating layer 15 may be the point where the insulating layer and the lower reflective layer contact each other.

[0021] Like the light-emitting element 100, the infrared light-emitting element 101 is also composed of a lower reflective layer 11B, a functional layer 12 including a light-emitting layer, an upper electrode 13, and a protective layer 14, in this order. Here, the lower reflective layer 11B can function as a lower electrode. Also, like the light-emitting element 100, an insulating layer 15 is provided to cover both ends of the lower reflective layer 11, and the insulating layer 15 is also called a pixel separation film or a bank.

[0022] The functional layer 12 may be composed of multiple layers. When the functional layer is an organic compound layer, the multiple layers may include a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer. The light-emitting layer emits light when holes injected from the anode and electrons injected from the cathode recombine in the organic compound layer. The light-emitting layer may be composed of a single layer or multiple layers.

[0023] Any of the light-emitting layers may contain a red light-emitting material, a green light-emitting material, a red light-emitting material, and an infrared light-emitting material. White light can also be obtained by mixing the respective light-emitting colors. Any of the light-emitting layers may contain light-emitting materials of complementary colors, such as a blue light-emitting material and a yellow light-emitting material. Different colors may be emitted by changing the materials or configurations contained in the light-emitting layers for each light-emitting pixel.

[0024] When the functional layer 12 can emit light in the wavelength range from the visible to the infrared region, the light emitting element 100 and the infrared light emitting element 101 may have one light emitting layer. That is, a plurality of light emitting elements and a plurality of infrared light emitting elements may share one light emitting layer. Alternatively, a light emitting layer may be provided for each of the light emitting elements and the infrared light emitting elements. In this case, the light emitting layer may be patterned for each of the light emitting elements 100 and the infrared light emitting element 101.

[0025] Furthermore, the upper electrode 13 may be shared by a plurality of light-emitting elements 100 and a plurality of infrared light-emitting elements 101. That is, a common upper electrode may be formed over the entire surface of the display region 9 in FIG.

[0026] Furthermore, the light-emitting element 100 and the infrared-light-emitting element 101 of this embodiment may have a so-called microcavity structure. That is, when the optical distance from the upper surfaces of the lower reflective layers 11A and 11B to the light-emitting position of the functional layer 12 is Lr and the phase shift when light of wavelength λ is reflected at the interface between the lower reflective layers 11A and 11B is Φr, the following formula (1) holds: Lr=(2m-(Φr / π))×(λ / 4) ···(1) Here, m is an integer equal to or greater than 0. The optical path length of the functional layer 12 can be optimized for each color so as to satisfy the above formula (1).

[0027] If the wavelength λ satisfies formula (1), the light of each color emitted by the light-emitting element 100 is intensified. However, even if a wavelength λ within a range of values ​​shifted by ±λ / 12 is used, the light emitted by the light-emitting element 100 and the infrared-emitting element 101 can be intensified. That is, in this embodiment, the optical distance Lr may be set based on a relationship with the wavelength λ of light so as to satisfy the following formula (2). Lr=(2m-(Φr / π))×(λ / 4)±λ / 12 ···(2)

[0028] If the optical distance from the light-emitting position of the functional layer 12 to the reflecting surface of the upper electrode 13 is Ls and the phase shift when light of wavelength λ is reflected at the interface of the upper electrode 13 is Φs, the following equation (3) holds for the optical distance Ls and the wavelength λ, where m' is an integer equal to or greater than 0.

[0029] Ls=(2m'-(Φs / π))×(λ / 4)=-(Φs / π)×(λ / 4) ···(3) As with formula (1), if the wavelength λ satisfies formula (3), the light emitted by the light emitting element 100 is intensified.

[0030] Here, with respect to formula (3), even if the wavelength λ is within a range of values ​​deviated by ±λ / 12, it is possible to intensify the light emitted by the light-emitting element 100. That is, in this embodiment, the relationship between the optical distance Ls and the wavelength λ may be set to satisfy the following formula (4). Ls=(2m'-(Φs / π))×(λ / 4)±λ / 12 =-(Φs / π)×(λ / 4)±λ / 12 ···(4)

[0031] Therefore, the total layer interference L due to the optical distance Lr and the optical distance Ls approximately satisfies the following equation (5). When the following equation (5) holds, the light of wavelength λ is intensified. L1=Lr+Ls=(2m-Φ / π)×(λ / 4) ···(5) Here, Φ is the sum of the phase shifts Φr+Φs when light of wavelength λ is reflected at the interface between the lower reflective layers 11A and 11B and the interface between the upper electrode 13.

[0032] Furthermore, although the wavelength λ of light that satisfies the formula (5) is intensified, it is also possible to intensify the light emitted by the light-emitting element 100 and the infrared-light-emitting element 101 even if the wavelength λ is within a range of values ​​that are shifted by ±λ / 12. That is, in this embodiment, the wavelength λ that satisfies the following formula (6) may be adopted. L1=Lr+Ls=(2m-Φ / π)×(λ / 4)±λ / 12 (6)

[0033] The optical distances of the display element and the infrared light-emitting element may be different. By adopting such a configuration, the display element can be set to a distance that intensifies visible light, and the infrared light-emitting element can be set to a distance that intensifies infrared light emission. By adopting the above configuration, the light-emitting element 100 and the infrared light-emitting element 101 can be configured to mainly emit visible light and emit infrared light, while sharing the functional layer 12.

[0034] Next, a method for reducing reflected light emitted when light from the display unit is incident on the infrared light emitting unit for detecting the line of sight in this embodiment will be described in detail with reference to Fig. 3. Here, the average reflectance of each of the lower reflective layer 11A and the lower reflective layer 11B at a certain wavelength is defined as RA. A , R.A. B Let's say.

[0035] The average reflectance RA may be the average value of reflectances measured at n positions every γ nm for light wavelengths of α nm to β nm for a given material. Here, the average value of reflectances can be calculated from the integral of the reflectance R(λ) of the reflective layer in the specified wavelength range of α nm to β nm in increments of γ nm using equation (7). TIFF2025164567000002.tif1697...(7) Here, the average reflectance of each of the lower reflective layers 11A and 11B is RA A , R.A. B Let's say.

[0036] In order to prevent the deterioration of visibility due to reflected light from the lower reflective layer 11B, it is effective to reduce the average reflectance in the visible light region of the lower reflective layer 11B. Here, the wavelength of the visible light region is set to 450 nm to 700 nm. Specifically, when the average reflectance in the visible light region of the lower reflective layer 11A and the lower reflective layer 11B in FIG. 3 is RA A >RA B By satisfying the above relationship, it is possible to reduce reflected light in the visible light range that is emitted when light from the display unit is incident on the infrared light emitting unit, and therefore it is possible to reduce degradation in display quality.

[0037] The average reflectance RA of the lower reflective layer 11B for light in the wavelength range of 400 nm to 600 nm is B The average reflectance RA from 600nm to 900nm B It is also preferable that the reflectance for light with a wavelength of 550 nm is smaller than RA A >RA B By making the reflectance have such a relationship, it is possible to reduce reflected light emitted when light from the display unit is incident on the infrared light emitting unit.

[0038] Also, R.A. B Regarding the reflectance, it is preferable that the reflectance for light in the wavelength range of 450 nm to 550 nm is 70% or less. B The reflectance should be greater than 70% in the range of 600nm to 900nm. B By setting the reflectance to the above values ​​for light wavelengths of 450 nm to 550 nm and 600 nm to 900 nm, deterioration of display quality can be suppressed and highly efficient infrared light emission is possible. As an example of a material that can be used for the reflective layer, the lower reflective layer 11A can be made of a metal containing at least one of Ag and Al, and the lower reflective layer 11B can be made of a metal containing at least one of Cu and Au, thereby making it possible to achieve appropriate reflectance for the reflective layer.

[0039] Second Embodiment In addition to the first embodiment, FIG. 7 shows color filters 19a-d formed on protective layer 15. A planarization layer may be provided between color filters 19a-d and protective layer 15. A pixel including color filters 19a-c is considered a sub-pixel, and three sub-pixels can be considered as one main pixel. Red, green, and blue are particularly preferred for the sub-pixels, and additive color mixing of these sub-pixels enables full-color display. Light emitted from light-emitting region 16 passes through color filter 19, thereby increasing color purity.

[0040] (Third embodiment) In addition to the first embodiment, Fig. 8 shows an infrared light emitting element 101 having a color filter 19d formed thereon. Also, in addition to the second embodiment, Fig. 9 shows an infrared light emitting element 101 having a color filter 19d formed thereon. The color filter 19d has absorption at 550 nm and can suppress reflected light around 550 nm, where visibility is high, and can suppress a decrease in visibility due to reflected light.

[0041] (Fourth embodiment) 10 differs from the first embodiment in that the lower reflective layer 11A and the lower reflective layer 11B do not have an electrode function, and an optical adjustment layer 17 and a transparent electrode 18 are formed on the upper layer of the lower reflective layer 11B. This embodiment can also be applied to the second and third embodiments.

[0042] Fifth Embodiment 11 shows that microlenses 20 are formed in addition to the first embodiment. Here, they are formed in both the display section and the infrared light emitting section, but they may be formed in only one of them. This embodiment can also be applied to the second to fourth embodiments.

[0043] [Configuration of organic light-emitting element] The organic light-emitting element of this embodiment is provided by forming an insulating layer, a lower electrode, a functional layer including a light-emitting layer, and an upper electrode on a substrate. A protective layer, a color filter, a microlens, etc. may be provided on the upper electrode. When a color filter is provided, a planarizing layer may be provided between the protective layer. The planarizing layer may be made of an acrylic resin, etc. The same applies when a planarizing layer is provided between the color filter and the microlens.

[0044] [substrate] The substrate constituting the organic light-emitting element may be made of at least one of quartz, glass, silicon, resin, and metal. Furthermore, the substrate may be provided with a switching element such as a transistor and wiring, and an insulating layer may be provided thereon. Any material can be used for the insulating layer, as long as it allows for the formation of contact holes so that wiring can be formed between the first electrode and the insulating layer, and ensures insulation from unconnected wiring. For example, resins such as polyimide, silicon oxide, silicon nitride, etc. can be used.

[0045] [electrode] A pair of electrodes can be used for the organic light-emitting element. The pair of electrodes may be an anode and a cathode. When an electric field is applied in the direction in which the organic light-emitting element emits light, the electrode with a higher potential is the anode, and the other is the cathode. It can also be said that the electrode that supplies holes to the light-emitting layer is the anode, and the electrode that supplies electrons is the cathode.

[0046] The anode material should have as high a work function as possible. For example, simple metals such as gold, platinum, silver, copper, nickel, palladium, cobalt, selenium, vanadium, and tungsten, or mixtures containing these metals, can be used for the anode. Alternatively, alloys combining these simple metals, or metal oxides such as tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), and zinc indium oxide can be used for the anode. Conductive polymers such as polyaniline, polypyrrole, and polythiophene can also be used for the anode.

[0047] These electrode materials may be used alone or in combination of two or more materials. The anode may be composed of one layer or multiple layers.

[0048] When the electrode of an organic light-emitting element is configured as a reflective electrode, the electrode material can be, for example, chromium, aluminum, silver, titanium, tungsten, molybdenum, or an alloy or laminate thereof. The above materials can also function as a reflective film without functioning as an electrode. Furthermore, when used as a transparent electrode, a transparent conductive oxide layer such as indium tin oxide (ITO) or indium zinc oxide can be used, but is not limited to these. Photolithography technology can be used to form the electrode.

[0049] On the other hand, materials with a low work function are preferable for the cathode. Examples include alkali metals such as lithium, alkaline earth metals such as calcium, and metals such as aluminum, titanium, manganese, silver, lead, and chromium, as well as mixtures containing these metals. Alloys combining these metals can also be used. Examples include magnesium-silver, aluminum-lithium, aluminum-magnesium, silver-copper, and zinc-silver. Metal oxides such as indium tin oxide (ITO) can also be used.

[0050] These electrode materials may be used alone or in combination of two or more. The cathode may have a single layer or a multi-layer structure. Among these, silver is preferably used, and a silver alloy is more preferable to reduce silver aggregation. The alloy ratio is not important as long as it can reduce silver aggregation. For example, the silver:other metal ratio may be 1:1, 3:1, etc.

[0051] The cathode may be a top-emission element using an oxide conductive layer such as ITO, or a bottom-emission element using a reflective electrode such as aluminum (Al), and is not particularly limited. The method for forming the cathode is not particularly limited, but DC and AC sputtering methods are preferred because they provide good film coverage and make it easier to reduce resistance.

[0052] [Pixel isolation layer] The pixel separation layer is formed of a silicon nitride (SiN) film, a silicon oxynitride (SiON) film, or a silicon oxide (SiO) film formed using a chemical vapor deposition (CVD) method. To increase the in-plane resistance of the organic compound layer, it is preferable that the organic compound layer, particularly the hole transport layer, be thinly deposited on the sidewalls of the pixel separation layer. Specifically, the thickness of the sidewalls can be thinned by increasing the taper angle of the sidewalls of the pixel separation layer or the thickness of the pixel separation layer, thereby increasing vignetting during deposition.

[0053] On the other hand, it is preferable to adjust the sidewall taper angle and film thickness of the pixel separation layer to such an extent that voids are not formed in the protective layer formed thereon. Since voids are not formed in the protective layer, the occurrence of defects in the protective layer can be reduced. Since the occurrence of defects in the protective layer is reduced, deterioration of reliability such as the occurrence of dark spots and poor conduction of the second electrode can be reduced.

[0054] According to this embodiment, charge leakage to adjacent pixels can be effectively suppressed even if the taper angle of the sidewall of the pixel separation layer is not steep. As a result of research by the present inventors, it was found that a taper angle in the range of 60 degrees to 90 degrees can sufficiently reduce charge leakage. The thickness of the pixel separation layer is preferably 10 nm to 150 nm. Similar effects can also be achieved even if the pixel electrode is composed only of a pixel electrode without a pixel separation layer. However, in this case, it is preferable to make the thickness of the pixel electrode half or less of the organic layer, or to make the edge of the pixel electrode forward tapered at less than 60 degrees, since this reduces short circuits in the organic light-emitting element.

[0055] [Organic compound layer] The organic compound layer of the organic light-emitting element may be formed as a single layer or multiple layers. When multiple layers are included, they may be called hole injection layer, hole transport layer, electron blocking layer, light-emitting layer, hole blocking layer, electron transport layer, or electron injection layer depending on their functions. The organic compound layer is mainly composed of organic compounds but may also contain inorganic atoms or inorganic compounds. For example, it may contain copper, lithium, magnesium, aluminum, iridium, platinum, molybdenum, zinc, etc. The organic compound layer may be disposed between the first electrode and the second electrode, or may be disposed in contact with the first electrode and the second electrode.

[0056] [Protective layer] In the organic light-emitting device of this embodiment, a protective layer may be provided on the second electrode. For example, by adhering glass provided with a moisture absorbent on the second electrode, it is possible to reduce the intrusion of water and the like into the organic compound layer and reduce the occurrence of display defects. In another embodiment, a passivation film such as silicon nitride may be provided on the cathode to reduce the intrusion of water and the like into the organic compound layer. For example, after forming the cathode, the cathode may be transferred to another chamber without breaking the vacuum, and a silicon nitride film with a thickness of 2 μm may be formed by CVD to serve as a protective layer. After the film formation by CVD, a protective layer may be provided using atomic layer deposition (ALD).

[0057] The material of the film formed by the ALD method is not limited, and may be silicon nitride, silicon oxide, aluminum oxide, etc. Silicon nitride may be further formed on the film formed by the ALD method by the CVD method. The film formed by the ALD method may have a smaller thickness than the film formed by the CVD method. Specifically, it may be 50% or less, or even 10% or less.

[0058] [Color Filter] In the organic light-emitting element of this embodiment, a color filter may be provided on the protective layer. For example, a color filter taking into account the size of the organic light-emitting element may be provided on a separate substrate and then bonded to the substrate on which the organic light-emitting element is provided, or a color filter may be patterned on the protective layer described above using photolithography technology. The color filter may be made of a polymer.

[0059] [Planarization layer] The organic light-emitting element of this embodiment may have a planarization layer between the color filter and the protective layer. The planarization layer is provided for the purpose of reducing unevenness of the underlying layer. When the purpose is not limited, the planarization layer may also be called a resin layer. The planarization layer may be composed of an organic compound, and may be either a low molecular weight compound or a high molecular weight compound, but is preferably a high molecular weight compound.

[0060] The planarizing layer may be provided above or below the color filter, and may be made of the same or different materials, such as polyvinyl carbazole resin, polycarbonate resin, polyester resin, ABS resin, acrylic resin, polyimide resin, phenol resin, epoxy resin, silicone resin, and urea resin.

[0061] [Microlens] The organic light-emitting element may have an optical component such as a microlens on its light-emitting side. The microlens may be made of acrylic resin, epoxy resin, or the like. The microlens may be intended to increase the amount of light extracted from the organic light-emitting element and control the direction of the extracted light. The microlens may have a hemispherical shape. When the microlens has a hemispherical shape, among the tangents to the hemisphere, there is a tangent that is parallel to the insulating layer, and the point of contact between the tangent and the hemisphere is the vertex of the microlens. The vertex of the microlens can be determined in the same way in any cross-sectional view.

[0062] In other words, among the tangents to the semicircle of the microlens in the cross-sectional view, there is a tangent that is parallel to the insulating layer, and the point of contact between this tangent and the semicircle is the vertex of the microlens. It is also possible to define the midpoint of the microlens. In the cross-section of the microlens, a line segment can be imagined from the point where an arc shape ends to the point where another arc shape ends, and the midpoint of this line segment can be called the midpoint of the microlens. The cross-section used to determine the vertex and midpoint may be a cross-section perpendicular to the insulating layer.

[0063] The microlens has a first surface having a convex portion and a second surface opposite the first surface. The second surface is preferably disposed closer to the functional layer than the first surface. To achieve this configuration, the microlens must be formed on the light-emitting element. When the functional layer is an organic layer, it is preferable to avoid processes that result in high temperatures during the manufacturing process. Furthermore, when the second surface is disposed closer to the functional layer than the first surface, it is preferable that the glass transition temperatures of all organic compounds that make up the organic layer are 100°C or higher, and more preferably 130°C or higher.

[0064] [Counter substrate] The organic light-emitting element of this embodiment may have an opposing substrate on the planarization layer. The opposing substrate is called an opposing substrate because it is provided at a position corresponding to the aforementioned substrate. The constituent material of the opposing substrate may be the same as that of the aforementioned substrate. When the aforementioned substrate is the first substrate, the opposing substrate can be the second substrate.

[0065] [Organic layer] The functional layers (hole injection layer, hole transport layer, electron blocking layer, light-emitting layer, hole blocking layer, electron transport layer, electron injection layer, etc.) including the light-emitting layer that constitute the organic light-emitting device of this embodiment are formed by the following method. The organic compound layer that constitutes the organic light-emitting device of this embodiment can be formed using a dry process such as vacuum deposition, ionization deposition, sputtering, or plasma. Instead of the dry process, a wet process can also be used in which the compound is dissolved in an appropriate solvent and a layer is formed by a known coating method (e.g., spin coating, dipping, casting, LB method, inkjet method, etc.).

[0066] Here, when a layer is formed by a vacuum deposition method or a solution coating method, crystallization is unlikely to occur and the layer has excellent stability over time. When a film is formed by a coating method, the film can be formed by combining with an appropriate binder resin.

[0067] Examples of binder resins include, but are not limited to, polyvinyl carbazole resin, polycarbonate resin, polyester resin, ABS resin, acrylic resin, polyimide resin, phenolic resin, epoxy resin, silicone resin, and urea resin. These binder resins may be used alone or in combination as homopolymers or copolymers. If necessary, known additives such as plasticizers, antioxidants, and ultraviolet absorbers may be used in combination.

[0068] [Pixel circuit] The light-emitting device having the organic light-emitting element of this embodiment may have a pixel circuit connected to the organic light-emitting element. The pixel circuit may be an active matrix type that controls the light emission of the first organic light-emitting element and the second organic light-emitting element independently. The active matrix type circuit may be voltage-programmed or current-programmed. The drive circuit has a pixel circuit for each pixel. The pixel circuit may have an organic light-emitting element, a transistor that controls the light emission luminance of the organic light-emitting element, a transistor that controls the light emission timing, a capacitor that holds the gate voltage of the transistor that controls the light emission luminance, and a transistor for connecting to GND without going through the light-emitting element.

[0069] The light-emitting device has a display area and a peripheral area arranged around the display area. The display area has a pixel circuit, and the peripheral area has a display control circuit. The mobility of a transistor constituting the pixel circuit may be smaller than the mobility of a transistor constituting the display control circuit. The slope of the current-voltage characteristics of the transistor constituting the pixel circuit may be smaller than the slope of the current-voltage characteristics of the transistor constituting the display control circuit. The slope of the current-voltage characteristics can be measured by the so-called Vg-Ig characteristics. The transistor constituting the pixel circuit is a transistor connected to a light-emitting element such as a first organic light-emitting element.

[0070] [Pixels] The organic light-emitting element of this embodiment has multiple pixels. Each pixel has sub-pixels that emit different colors. The sub-pixels may each emit RGB colors, for example. The pixel emits light in a region also called a pixel aperture. This region is the same as the first region. The pixel aperture may be 15 μm or less, or 5 μm or more. More specifically, it may be 11 μm, 9.5 μm, 7.4 μm, 6.4 μm, etc. The distance between the sub-pixels may be 10 μm or less, specifically, 8 μm, 7.4 μm, or 6.4 μm.

[0071] The pixels may have a known arrangement in plan view. For example, they may be a stripe arrangement, a delta arrangement, a pentile arrangement, or a Bayer arrangement. The shape of the sub-pixels in plan view may be any known shape. For example, they may be rectangular, quadrilaterals such as diamonds, or hexagons. Note that a sub-pixel shape that is close to a rectangle is considered to be included in the rectangle. Therefore, the shape of the sub-pixels may be a shape that approximates any of the known shapes described above. A pixel can be configured by combining the shape of the sub-pixels and the pixel arrangement.

[0072] (Application of light-emitting devices to equipment) 12 is a schematic diagram illustrating an example in which the light-emitting device according to the above embodiment is applied to a display device, which is an example of an electronic device. The display device 1000 may have a touch panel 1003, a display panel 1005, a frame 1006, a circuit board 1007, and a battery 1008 between an upper cover 1001 and a lower cover 1009. The touch panel 1003 and the display panel 1005 are connected by flexible printed circuits FPCs 1002 and 1004. Transistors are printed on the circuit board 1007. The battery 1008 may not be provided if the display device is not a portable device, and may be provided in a different position even if the display device is a portable device.

[0073] The display device according to this embodiment may have color filters having red, green, and blue colors, which may be arranged in a delta arrangement.

[0074] The display device according to the present embodiment may be used as a display unit of a mobile terminal. In this case, the display device may have both a display function and an operation function. Examples of the mobile terminal include a mobile phone such as a smartphone, a tablet, and a head-mounted display.

[0075] The display device according to this embodiment may be used as a display unit of an imaging device having an optical unit with a plurality of lenses and an imaging element that receives light that has passed through the optical unit. The imaging device may have a display unit that displays information acquired by the imaging element. The display unit may be a display unit exposed to the outside of the imaging device or a display unit disposed within a viewfinder. The imaging device may be a digital camera or a digital video camera.

[0076] 13A is a schematic diagram showing an imaging device as an example of an electronic device according to this embodiment. The imaging device 1100 may include a viewfinder 1101, a rear display 1102, an operation unit 1103, and a housing 1104. The viewfinder 1101 may include a display device to which the light-emitting device according to the above embodiment is applied. In this case, the display device may display not only an image to be captured, but also environmental information, imaging instructions, and the like. The environmental information may include the intensity of external light, the direction of external light, the speed at which the subject is moving, the possibility that the subject will be blocked by an obstruction, and the like.

[0077] Since the optimum timing for capturing an image is very short, it is better to display information as soon as possible. Therefore, it is preferable to use a display device using the organic light-emitting element of the present invention. This is because the organic light-emitting element has a fast response speed. A display device using an organic light-emitting element can be used more preferably than a liquid crystal display device, which requires a high display speed.

[0078] The imaging device 1100 has an optical section (not shown). The optical section has multiple lenses, which form an image on an imaging element housed in a housing 1104. The focus of the multiple lenses can be adjusted by adjusting their relative positions. This operation can also be performed automatically. The imaging device may also be called a photoelectric conversion device. Instead of sequentially capturing images, the photoelectric conversion device can include an imaging method that detects the difference from the previous image, or a method of cutting out an image from a constantly recorded image, etc.

[0079] FIG. 13(b) is a schematic diagram illustrating an example of an electronic device according to this embodiment. The electronic device 1200 has a display unit 1201, an operation unit 1202, and a housing 1203. The light-emitting device according to the above embodiment can be applied to the display unit 1201. The housing 1203 may have a circuit, a printed circuit board having the circuit, a battery, and a communication unit. The operation unit 1202 may be a button or a touch panel type reaction unit. The operation unit may be a biometric recognition unit that recognizes a fingerprint to unlock the device, etc. An electronic device having a communication unit can also be called a communication device. The electronic device may further have a camera function by including a lens and an image sensor. An image captured by the camera function is displayed on the display unit. Examples of the electronic device include a smartphone and a laptop computer.

[0080] An application example of the display device of each of the above-described embodiments will be described with reference to Fig. 14. The display device can be applied to a system that can be attached as a wearable device, such as smart glasses, an HMD, or a smart contact lens. An image capturing and displaying device used in such an application example includes an image capturing device capable of photoelectrically converting visible light and a displaying device capable of emitting visible light.

[0081] 14(a) illustrates glasses 1600 (smart glasses) according to one application example. An imaging device 1602 such as a CMOS sensor or SPAD is provided on the front side of a lens 1601 of the glasses 1600. Furthermore, a display device employing a light-emitting device according to any of the above embodiments is provided on the back side of the lens 1601.

[0082] The glasses 1600 further include a control device 1603. The control device 1603 functions as a power source that supplies power to the image capture device 1602 and the display device according to each embodiment. The control device 1603 also controls the operations of the image capture device 1602 and the display device. The lens 1601 is formed with an optical system for focusing light onto the image capture device 1602.

[0083] FIG. 14(b) illustrates glasses 1610 (smart glasses) according to one application example. The glasses 1610 have a control device 1612. The control device 1612 is equipped with an imaging device corresponding to the imaging device 1602 and a display device. The light-emitting device according to each of the above embodiments can be applied to the display device. An optical system for projecting light emitted by the display device in the control device 1612 is formed in the lens 1611, and an image is projected onto the lens 1611. The control device 1612 functions as a power source that supplies power to the imaging device and the display device, and controls the operation of the imaging device and the display device. The control device may have a gaze detection unit that detects the gaze of the wearer. Infrared rays may be used to detect the gaze.

[0084] The infrared light emitting unit emits infrared light toward the eyeball of a user gazing at a displayed image. An imaging unit having a light receiving element detects the reflected light of the emitted infrared light from the eyeball, thereby obtaining an image of the eyeball. By including a reduction unit that reduces the light from the infrared light emitting unit to the display unit in a planar view, degradation of image quality is reduced.

[0085] The gaze of the user relative to the displayed image is detected from an image of the eyeball obtained by capturing infrared light. Any known method can be used for gaze detection using the image of the eyeball. As an example, a gaze detection method based on the Purkinje image formed by reflection of irradiated light on the cornea can be used.

[0086] More specifically, gaze detection processing is performed based on the pupil-corneal reflex method, which calculates a gaze vector representing the direction (rotation angle) of the eyeball based on the pupil image and Purkinje image included in the captured image of the eyeball, thereby detecting the user's gaze.

[0087] A display device according to one embodiment of the present invention may include an imaging device having a light receiving element, and may control the display image of the display device based on user line-of-sight information from the imaging device. Specifically, the display device determines a first display area on which the user gazes and a second display area other than the first display area based on the line-of-sight information. The first display area and the second display area may be determined by a control device of the display device, or may be determined by an external control device and received. In the display area of ​​the display device, the display resolution of the first display area may be controlled to be higher than the display resolution of the second display area. In other words, the resolution of the second display area may be lower than the resolution of the first display area.

[0088] Furthermore, the first display area and the first display region may be determined based on gaze information. Note that AI may be used to determine the first display area and the high-priority area. The AI ​​may be a model configured to estimate the gaze angle and the distance to the object in the gaze from the image of the eyeball, using the image of the eyeball and the actual gaze direction of the eyeball in the image as training data. The AI ​​program may be included in the display device, the imaging device, or an external device. If included in the external device, it is transmitted to the display device via communication.

[0089] When display control is performed based on visual recognition detection, the smart glasses can be preferably applied to smart glasses that further include an imaging device for capturing images of the outside world. The smart glasses can display captured external information in real time.

[0090] (Other embodiments) (Item 1) A light emitting device having a first light emitting element that emits visible light and a second light emitting element that emits infrared light on a substrate, the first light-emitting element has a first light-emitting layer and a first reflective layer between the substrate and the first light-emitting layer; the second light-emitting element has a second light-emitting layer and a second reflective layer between the substrate and the second light-emitting layer; an average reflectance of the second reflective layer for visible light that is lower than an average reflectance of the first reflective layer for visible light; A light-emitting device characterized by: (Item 2) 2. The light-emitting device according to item 1, wherein a light-receiving element is provided on the substrate. (Item 3) 3. The light emitting device according to item 1 or 2, wherein the average reflectance of the second reflective layer for light with a wavelength of 450 nm to 550 nm is smaller than the average reflectance of the second reflective layer for light with a wavelength of 600 nm to 900 nm. (Item 4) 4. The light emitting device according to any one of items 1 to 3, wherein the average reflectance of the second reflective layer for light with a wavelength of 450 nm to 550 nm is 70% or less, and the average reflectance of the second reflective layer for light with a wavelength of 600 nm to 900 nm is greater than 70%. (Item 5) 5. The light emitting device according to any one of items 1 to 4, wherein the reflectance of the second reflective layer for light with a wavelength of 550 nm is smaller than the reflectance of the first reflective layer for light with a wavelength of 550 nm. (Item 6) 6. The light emitting device according to any one of items 1 to 5, wherein a filter that absorbs light with a wavelength of 550 nm is provided on the side from which light from the second light emitting element is extracted. (Item 7) 7. The light emitting device according to any one of items 1 to 6, wherein a microlens is disposed on the light extraction side of at least one of the first light emitting element and the second light emitting element. (Item 8) 8. The light emitting device according to any one of items 1 to 7, wherein at least one of the first light emitting layer and the second light emitting layer contains an organic compound. (Item 9) A light emitting device having a first light emitting element that emits visible light and a second light emitting element that emits infrared light on a substrate, the first light-emitting element has a first light-emitting layer and a first reflective layer between the substrate and the first light-emitting layer; the second light-emitting element has a second light-emitting layer and a second reflective layer between the substrate and the second light-emitting layer; the first reflective layer contains at least one of silver and aluminum, and the second reflective layer contains at least one of copper and gold; Light-emitting device. (Item 10) 10. The light emitting device according to item 9, wherein a light receiving element is provided on the substrate. (Item 11) 11. The light-emitting device according to item 9 or 10, wherein the first reflective layer and the second reflective layer are electrodes that apply a voltage to the first light-emitting layer and the second light-emitting layer, respectively. (Item 12) 12. The light emitting device according to any one of items 9 to 11, further comprising a filter for absorbing light of a wavelength of 550 nm on the side from which light of the second light emitting element is extracted. (Item 13) 13. The light emitting device according to any one of items 9 to 12, wherein a microlens is arranged on the side from which light is extracted in at least one of the first light emitting element and the second light emitting element. (Item 14) 14. The light emitting device according to any one of items 9 to 13, wherein at least one of the first light emitting layer and the second light emitting layer contains an organic compound. (Item 15) 15. An imaging device comprising: an optical unit having a plurality of lenses; an imaging element that receives light that has passed through the optical unit; and a display unit that displays an image captured by the imaging element, wherein the display unit comprises a light-emitting device according to any one of items 1 to 14. (Item 16) 15. A display device comprising: a display unit having the light-emitting device according to any one of items 1 to 14; and a housing in which the display unit is provided. (Item 17) 15. An electronic device comprising: a display unit having the light-emitting device according to any one of items 1 to 14; a housing in which the display unit is provided; and a communication unit provided in the housing for communicating with the outside. (Item 18) 1. A wearable device having a display device for displaying an image, A wearable device characterized in that the display device has the light-emitting device described in any one of items 1 to 14.

[0091] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, the appended items are provided to publicize the scope of the invention. [Explanation of symbols]

[0092] 1 display device, 2 insulating layer, 3 display section, 4 infrared light emitting section, 5 imaging section, 6 user's eyeball, 7 display light, 8 infrared light, 11 lower reflective layer, 12 functional layer, 13 upper electrode, 14 protective layer, 15 insulating layer, 16 light emitting region, 100 light emitting element, 101 infrared light emitting element

Claims

1. A light emitting device having a first light emitting element that emits visible light and a second light emitting element that emits infrared light on a substrate, the first light-emitting element has a first light-emitting layer and a first reflective layer between the substrate and the first light-emitting layer; the second light-emitting element has a second light-emitting layer and a second reflective layer between the substrate and the second light-emitting layer, an average reflectance of the second reflective layer for visible light that is smaller than an average reflectance of the first reflective layer for visible light; A light emitting device characterized by:

2. 2. The light emitting device according to claim 1, wherein a light receiving element is provided on the substrate.

3. 2. The light emitting device according to claim 1, wherein the average reflectance of the second reflective layer for light with a wavelength of 450 nm to 550 nm is smaller than the average reflectance of the second reflective layer for light with a wavelength of 600 nm to 900 nm.

4. 2. The light-emitting device of claim 1, wherein the average reflectance of the second reflective layer for light with a wavelength of 450 nm to 550 nm is 70% or less, and the average reflectance of the second reflective layer for light with a wavelength of 600 nm to 900 nm is greater than 70%.

5. 2. The light emitting device according to claim 1, wherein the reflectance of the second reflective layer for light with a wavelength of 550 nm is smaller than the reflectance of the first reflective layer for light with a wavelength of 550 nm.

6. 2. The light emitting device according to claim 1, further comprising a filter for absorbing light of a wavelength of 550 nm provided on the side from which light from the second light emitting element is extracted.

7. 2. The light emitting device according to claim 1, wherein a microlens is disposed on a side from which light is extracted from at least one of the first light emitting element and the second light emitting element.

8. 2. The light-emitting device according to claim 1, wherein at least one of the first light-emitting layer and the second light-emitting layer contains an organic compound.

9. A light emitting device having a first light emitting element that emits visible light and a second light emitting element that emits infrared light on a substrate, the first light-emitting element has a first light-emitting layer and a first reflective layer between the substrate and the first light-emitting layer; the second light-emitting element has a second light-emitting layer and a second reflective layer between the substrate and the second light-emitting layer, the first reflective layer contains at least one of silver and aluminum, and the second reflective layer contains at least one of copper and gold; Light-emitting device.

10. 10. The light emitting device according to claim 9, wherein a light receiving element is provided on the substrate.

11. 10. The light emitting device according to claim 9, wherein the first reflective layer and the second reflective layer are electrodes for applying a voltage to the first light emitting layer and the second light emitting layer, respectively.

12. 10. The light emitting device according to claim 9, further comprising a filter for absorbing light of a wavelength of 550 nm on the side from which light of the second light emitting element is extracted.

13. 10. The light emitting device according to claim 9, wherein a microlens is disposed on a side from which light is extracted from at least one of the first light emitting element and the second light emitting element.

14. 10. The light emitting device according to claim 9, wherein at least one of the first light emitting layer and the second light emitting layer contains an organic compound.

15. 15. An imaging device comprising: an optical section having a plurality of lenses; an imaging element that receives light that has passed through the optical section; and a display section that displays an image captured by the imaging element, wherein the display section comprises a light-emitting device according to any one of claims 1 to 14.

16. A display device comprising: a display portion having the light-emitting device according to claim 1; and a housing in which the display portion is provided.

17. 15. An electronic device comprising: a display unit having the light-emitting device according to claim 1; a housing in which the display unit is provided; and a communication unit provided in the housing for communicating with an external device.

18. 1. A wearable device having a display device for displaying an image, A wearable device, wherein the display device comprises the light-emitting device according to claim 1 .

Images