Light-emitting element

Abstract

To provide a novel light-emitting element, or to achieve both high efficiency and long lifespan. We provide a novel light-emitting element. [Solution] A light-emitting element having a light-emitting layer between a pair of electrodes, wherein the light-emitting element has a first light-emitting layer It has a first light-emitting layer and a second light-emitting layer, the first light-emitting layer having a fluorescent material and the second light-emitting layer having phosphorus A light material is provided, and a first emission spectrum is emitted from a first light-emitting layer, and from a second light-emitting layer... The difference in peak values ​​between the second emitted emission spectrum and the first one is within 30 nm.

Description

[Technical Field]

[0001] One aspect of the present invention provides a light-emitting layer between a pair of electrodes, which generates light when an electric field is applied. This relates to a light-emitting element. It also relates to a light-emitting device, display device, electronic device, and having the above-mentioned light-emitting element. Regarding lighting devices.

[0002] Furthermore, one aspect of the present invention is not limited to the above-mentioned technical field. One aspect of the technical field relates to a product, method, or method of manufacture. One aspect of the invention is a process, machine, manufacture, or composition. This relates to (of matter). Therefore, the disclosures disclosed in this specification more specifically are as follows: One aspect of the technology described is semiconductor devices, display devices, liquid crystal display devices, light-emitting devices, and lighting. Examples include devices, energy storage devices, memory devices, methods for driving them, or methods for manufacturing them. It can be listed. [Background technology]

[0003] A light-emitting element (organic EL) has an organic compound, which is a light-emitting material, between a pair of electrodes. Electroluminescence (EL) elements (also called electroluminescent elements) With characteristics such as being thin, lightweight, fast response, and low voltage drive, it is the next generation of flat panel displays. It is attracting attention for this reason. In addition, displays using organic EL elements have improved contrast and image quality. It also boasts superior quality and a wide viewing angle.

[0004] In the case of such organic EL elements, electrons are supplied from the cathode and holes from the anode. The electrons and holes are injected into the EL layer, and an electric current flows. Then, the injected electrons and holes recombine. Therefore, the luminescent organic compound enters an excited state, and light emission can be obtained.

[0005] Excited states of organic compounds include singlet excited states (S * ) and triplet excited state (T * )but Yes, the emission from the singlet excited state is called fluorescence, and the emission from the triplet excited state is called phosphorescence. And the statistical generation ratio in the light-emitting element is S * :T * Considering the ratio to be 1:3 It is being obtained.

[0006] Materials that emit light from a singlet excited state (hereinafter referred to as fluorescent materials) typically exhibit the following characteristics at room temperature: No luminescence (phosphorescence) was observed from the triplet excited state, but no luminescence (fluorescence) was observed from the singlet excited state. A small amount is observed. Therefore, the internal quantum efficiency (injection) in a light-emitting device using a fluorescent material is The theoretical limit of the ratio of photons generated to the number of carriers is S * :T * = 1:3 The figure is set at 25% based on the following reasoning.

[0007] On the other hand, if a material that emits light from a triplet excited state (hereinafter referred to as a phosphorescent material) is used, Luminescence (phosphorescence) from the excited state is observed. Furthermore, phosphorescent materials are prone to intersystem crossing. Therefore, the internal quantum efficiency can theoretically reach 100%. In other words, the light-emitting element using phosphorescent material This method achieves higher luminescence efficiency than light-emitting devices using fluorescent materials. For this reason, In recent years, there has been a surge in the development of light-emitting devices using phosphorescent materials in order to achieve highly efficient light-emitting devices. (See, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2012-186461 [Overview of the project] [Problems that the invention aims to solve]

[0009] Light-emitting devices using phosphorescent materials can achieve higher luminescence efficiency than light-emitting devices using fluorescent materials. On the other hand, light-emitting devices using phosphorescent materials have a shorter lifespan than light-emitting devices using fluorescent materials. In particular, phosphorescent materials whose emission wavelength is on the short wavelength side, or in other words, those that emit light in the blue wavelength region. In light-emitting devices using phosphorescent materials with spectral peaks, both high efficiency and long lifespan are possible. It is difficult to obtain characteristics that fully satisfy the requirements.

[0010] In view of the above problems, one aspect of the present invention aims to provide a novel light-emitting element. Alternatively, in one aspect of the present invention, a new mechanism is available that can achieve both high efficiency and extended lifespan. One of the objectives is to provide a standard light-emitting element.

[0011] Alternatively, in another aspect of the present invention, a light-emitting device, electronic device, and lighting device having the above-mentioned light-emitting element. One of the objectives is to provide a lighting device.

[0012] Furthermore, the description of these problems does not preclude the existence of other problems. One approach does not require that all of these issues be resolved. The title will become clear from the description in the specification, drawings, claims, etc. It is possible to extract other issues from the descriptions in the drawings, claims, etc. [Means for solving the problem]

[0013] One aspect of the present invention is a light-emitting element having a light-emitting layer between a pair of electrodes, wherein the light-emitting element is It has a first light-emitting layer and a second light-emitting layer, the first light-emitting layer having a fluorescent material and the second light-emitting layer The layer has a phosphorescent material and emits a first emission spectrum from the first emission layer and a second emission The difference in peak values ​​between the second emission spectrum emitted from the photolayer and the first emission spectrum is within 30 nm. It is an optical element.

[0014] Furthermore, in the above embodiment, the fluorescent material and the phosphorescent material emit light of the same color or a similar color. Preferably. Also, in the above embodiment, the first emission spectrum and the second emission spectrum Preferably, it has a peak value in the blue wavelength region.

[0015] Another aspect of the present invention is a light-emitting element having a light-emitting layer between a pair of electrodes, wherein light emission The element has a first EL layer and a second EL layer, and the first EL layer has a first light-emitting layer. The device has a second light-emitting layer, the first light-emitting layer has a fluorescent material, and the second light-emitting layer has a first phosphorus The optical material is present, and the second EL layer has a third light-emitting layer, and the third light-emitting layer is a second phosphorescent material It has a first emission spectrum emitted from the first emission layer and a second emission spectrum emitted from the second emission layer. This is a light-emitting element in which the difference between the peak values ​​of the second emission spectrum and the first emission spectrum is within 30 nm.

[0016] Furthermore, in the above embodiment, the fluorescent material and the first phosphorescent material emit light of the same color or a similar color. This is preferable. Also, in the above embodiment, the first emission spectrum and the second emission spectrum Preferably, the torque has a peak value in the blue wavelength region.

[0017] Another aspect of the present invention is a light-emitting element having a light-emitting layer between a pair of electrodes, wherein light emission The element has a first EL layer and a second EL layer, and the first EL layer has a first light-emitting layer. The device has a second light-emitting layer, the first light-emitting layer has a fluorescent material, and the second light-emitting layer has a first phosphorus The optical material has a second EL layer which has a third light-emitting layer and a fourth light-emitting layer, and the third light-emitting layer The layer has a second phosphorescent material, the fourth light-emitting layer has a third phosphorescent material, and the first light-emitting layer The first emission spectrum emitted from the first emission layer and the second emission spectrum emitted from the second emission layer This is a light-emitting element in which the difference between the peak values ​​of and is within 30 nm.

[0018] Furthermore, in the above embodiment, the fluorescent material and the first phosphorescent material emit light of the same color or a similar color. This is preferable. Also, in the above embodiment, the first emission spectrum and the second emission spectrum Preferably, the torque has a peak value in the blue wavelength region.

[0019] Another aspect of the present invention is a light-emitting element having the above-described element and a color filter. It is a device. Another aspect of the present invention is a light-emitting element of the above aspect or the light-emitting device of the above aspect. The present invention is an electronic device having a touch sensor. Another aspect of the present invention is the present invention This is a lighting device having an optical element or an electronic device of the above embodiment and a housing. [Effects of the Invention]

[0020] According to one aspect of the present invention, a novel light-emitting element can be provided. Or, according to one aspect of the present invention Depending on the configuration, this invention provides a novel light-emitting element that can achieve both high efficiency and long lifespan. It is possible. Alternatively, according to one aspect of the present invention, a light-emitting device having the above-mentioned light-emitting element, an electronic device We can provide a device and a lighting device.

[0021] Furthermore, the description of these effects does not preclude the existence of other effects. One embodiment does not necessarily have to possess all of these effects. Furthermore, other effects may be considered. This will become clear from the description in the specification, drawings, claims, etc., and the specification, drawings It is possible to extract effects other than those mentioned above from the descriptions in the surfaces, claims, etc. [Brief explanation of the drawing]

[0022] [Figure 1] A schematic cross-sectional diagram illustrating a light-emitting element. [Figure 2] A schematic cross-sectional diagram illustrating a light-emitting element. [Figure 3] A schematic cross-sectional diagram illustrating a light-emitting element. [Figure 4] A diagram illustrating the element characteristics of light-emitting element 1 and light-emitting element 2. [Figure 5] A diagram illustrating the emission spectra of light-emitting element 1 and light-emitting element 2. [Figure 6] A diagram illustrating the brightness degradation of light-emitting elements 1 and 2. [Figure 7] A diagram illustrating the brightness degradation of light-emitting elements 1 to 3. [Figure 8] A schematic cross-sectional diagram illustrating the light-emitting element, and a diagram illustrating the correlation of energy levels in the light-emitting layer. [Figure 9] A schematic cross-sectional diagram illustrating the light-emitting element, and a diagram illustrating the correlation of energy levels in the light-emitting layer. [Figure 10] A schematic cross-sectional diagram illustrating the light-emitting element, and a diagram illustrating the correlation of energy levels in the light-emitting layer. [Figure 11] A schematic cross-sectional diagram illustrating a light-emitting element. [Figure 12] A schematic cross-sectional diagram illustrating a light-emitting element. [Figure 13] A schematic cross-sectional diagram illustrating a light-emitting element. [Figure 14] Block diagrams and circuit diagrams illustrating the display device. [Figure 15] A circuit diagram illustrating the pixel circuitry of a display device. [Figure 16] A circuit diagram illustrating the pixel circuitry of a display device. [Figure 17] A perspective view showing an example of a touch panel. [Figure 18] A cross-sectional view showing an example of a display panel and touch sensor. [Figure 19] A cross-sectional view showing an example of a touch panel. [Figure 20] Block diagram and timing chart of the touch sensor. [Figure 21] Circuit diagram of a touch sensor. [Figure 22] A perspective view illustrating the display module. [Figure 23] A diagram illustrating electronic devices. [Figure 24] Perspective and cross-sectional views illustrating the light-emitting device. [Figure 25] A cross-sectional view illustrating the light-emitting device. [Figure 26] A diagram illustrating lighting equipment and electronic devices. [Modes for carrying out the invention]

[0023] The embodiments of the present invention will be described in detail below with reference to the drawings. However, one embodiment of the present invention The description below is not limited to the form, and the invention may be described in any form without departing from the spirit and scope of the present invention. And the details can be changed in various ways. Therefore, one aspect of the present invention is as shown below. This should not be interpreted as being limited to the form of implementation or the content of the examples provided.

[0024] For the sake of ease of understanding, the position, size, and scope of each component shown in the drawings, etc., are as follows: The actual location, size, and range may not be represented. Therefore, one of the disclosed inventions The embodiments are not necessarily limited to the location, size, scope, etc., disclosed in drawings, etc.

[0025] Furthermore, the ordinal numbers used in this specification, etc., as "1st," "2nd," etc., are used for convenience only. It does not indicate the order of processes or stacking order. Therefore, for example, "the first" is not "the second." This can be appropriately replaced with "" or "the third," etc., in the explanation. The ordinal numbers used and the ordinal numbers used to specify one aspect of the present invention do not coincide. There is a match.

[0026] Furthermore, in this specification and other documents, when describing the structure of the invention using drawings, the same thing is used The symbols used are consistent across different drawings.

[0027] Furthermore, in this specification, the terms "membrane" and "layer" are interchangeable. It is possible to change the term. For example, the term "conductive layer" can be changed to the term "conductive film." It may be possible to change it. Or, for example, change the term "insulating film" to "insulating layer". In some cases, it may be possible to change the terminology to this.

[0028] (Embodiment 1) In this embodiment, a light-emitting element according to one aspect of the present invention will be described with reference to Figures 1 to 7. ru.

[0029] <1-1. Configuration of light-emitting element 1> Figures 1(A) and 1(B) are schematic cross-sectional diagrams illustrating a light-emitting element 100 according to one embodiment of the present invention.

[0030] The light-emitting element 100 shown in Figure 1(A) has a first electrode 104 and a second electrode 114 between them. It has a first light-emitting layer 110 and a second light-emitting layer 112. Also, in Figure 1(A) In addition to the first light-emitting layer 110 and the second light-emitting layer 112, the light-emitting element 100 also has a hole injection layer 1 31, it has a hole transport layer 132, an electron transport layer 133, and an electron injection layer 134.

[0031] More specifically, the light-emitting element 100 has a first electrode 104 on the substrate 102 and a first electrode 104 hole injection layer 131, hole transport layer 132 on hole injection layer 131, hole transport layer A first light-emitting layer 110 on 132, a second light-emitting layer 112 on the first light-emitting layer 110, and a second The electron transport layer 133 on the light-emitting layer 112, and the electron injection layer 134 on the electron transport layer 133, It has a second electrode 114 on the sub-injection layer 134.

[0032] Note that the layers between the pair of electrodes (here, hole injection layer 131, hole transport layer 132, 1 The first light-emitting layer 110, the second light-emitting layer 112, the electron transport layer 133, and the electron injection layer 134) Let's group them together as EL layer 108.

[0033] The first light-emitting layer 110 has at least a fluorescent material. In addition to the fluorescent material, the system may also contain other materials such as a host material or an assist material. For example, in the first light-emitting layer 110, the host material is present in the largest amount by weight, and the fluorescent material The material is dispersed in the host material. The S1 level of the host material in the first light-emitting layer 110 is the fluorescent material. The T1 level of the host material is greater than the S1 level of the material, and the T1 level of the host material is smaller than the T1 level of the fluorescent material. It is preferable.

[0034] Furthermore, the second light-emitting layer 112 has at least a phosphorescent material. 2. Even if it has other materials such as a host material or assist material in addition to the phosphorescent material, Good. For example, in the second light-emitting layer 112, the host material is present in the largest amount by weight. The phosphorescent material is dispersed in the host material. The T1 level of the host material in the second light-emitting layer 112 is It is preferable that the level is greater than the T1 level of the fluorescent material.

[0035] Furthermore, the fluorescent material of the first light-emitting layer 110 is particularly light-emitting in the blue wavelength region. A material having a peak is preferred. Also, the phosphorescent material of the second light-emitting layer 112 and In particular, materials having a peak in the emission spectrum in the blue wavelength region are preferred. The wavelength range is preferably 400 nm to 500 nm, and more preferably 420 nm. It is between m and 480 nm.

[0036] The first emission spectrum emitted from the first light-emitting layer 110 and the second light-emitting layer 112 The difference in peak values ​​between the emitted second emission spectrum and the first emission spectrum is within 30 nm, preferably 25 nm. It is within m, more preferably within 20 nm. In other words, it is emitted from the first light-emitting layer 110. The emitted light color and the light color emitted from the second light-emitting layer 112 are the same color or of the same color family. It would be desirable to have it.

[0037] For example, a blue fluorescent material is used in the first light-emitting layer 110, and a blue phosphorus is used in the second light-emitting layer 112. By using optical materials, the light-emitting element 100 can achieve both high efficiency and a long lifespan. It becomes possible.

[0038] Furthermore, in Figure 1(A), the first light-emitting layer 110 and the second light-emitting layer 112 are mutually... While examples of contact configurations have been given, the system is not limited to these. For example, as shown in Figure 1(B) A buffer layer 140 may be provided between the first light-emitting layer 110 and the second light-emitting layer 112. .

[0039] The buffer layer 140 is a host material or phosphorescent material generated in the second light-emitting layer 112. From the excited state, a dexter mechanism is used to convert to the host material or fluorescent material in the first light-emitting layer 110. It is provided to prevent energy transfer (especially triplet energy transfer). Therefore, The buffer layer 140 only needs to be a few nanometers thick. Specifically, 0.1 nm to 20 nm thick. It is less than or equal to m, or between 1 nm and 10 nm, or between 1 nm and 5 nm.

[0040] The buffer layer 140 may be composed of a single material, but it may also consist of a hole transport material and an electron transport material. Both types of materials may be included. When composed of a single material, the bipolar material is used. It may be used. Here, a bipolar material is one in which the ratio of electron-to-hole mobility is 100 or less. This refers to a material that transports holes or electrons. The material contained in buffer layer 140 is a hole transport material or an electron transport material. Materials can be used. For hole-transporting materials or electron-transporting materials, see below. Furthermore, the material contained in the buffer layer 140 is the host material of the second light-emitting layer 112. It is preferable to form it from the same material. This makes it easier to manufacture the light-emitting element 100. Alternatively, the driving voltage of the light-emitting element 100 is reduced.

[0041] For example, if the buffer layer 140 is the same as the host material and assist material of the second light-emitting layer 112 When formed from the material, the first light-emitting layer 110 and the second light-emitting layer 112 are, the second light-emitting layer The structure consists of 112 layers that do not contain phosphorescent material (buffer layer 140) stacked on top of each other. This configuration allows the buffer layer 140 and the second light-emitting layer 112 to be made of phosphorescent material. It becomes possible to perform deposition without any additives. To put the above configuration in other words, the buffer layer 140 is a phosphorescent material The first light-emitting layer 112 has a region that does not contain the phosphorescent material, and the second light-emitting layer 112 has a region that contains the phosphorescent material.

[0042] Furthermore, the material contained in the buffer layer 140 is different from the host material of the second light-emitting layer 112. A high T1 level is acceptable.

[0043] For example, if the buffer layer 140 has a hole transport material and an electron transport material, By adjusting the mixing ratio of transportable material and electron transportable material, the carrier recombination region can be improved. The first electrode 104 and the second electrode 114 can be adjusted. In the case of anode and cathode, increasing the proportion of hole transport material in buffer layer 140 allows The rear recombination region can be shifted from the first electrode 104 side to the second electrode 114 side. This allows for an increase in the contribution of light emission from the second light-emitting layer 112. Therefore, by increasing the proportion of electron transport material in buffer layer 140, the carrier recombination region is increased. The second electrode 114 can be shifted from the side of the first electrode 104, and the first light-emitting layer 11 This allows for an increase in the contribution of light emission from zero.

[0044] Furthermore, in the buffer layer 140, the hole transport material and the electron transport material form an excited complex. It may be formed, which effectively prevents the diffusion of excitons. Specifically, From the excited state of the host material or phosphorescent material of the second light-emitting layer 112, the first light-emitting layer 110 This can prevent energy transfer to the host material or fluorescent material.

[0045] Furthermore, in Figures 1(A) and 1(B), the first light-emitting layer 110 is located on the side of the first electrode 104. And, although an example was given of a configuration in which the second light-emitting layer 112 is located on the side of the second electrode 114, It is not limited to this. For example, as shown in Figures 2(A) and 2(B), the first light-emitting layer 110 is the second The configuration is such that the second light-emitting layer 112 is located on the electrode 114 side and the second light-emitting layer 112 is located on the first electrode 104 side. That's good too.

[0046] <1-2. Characteristics of light-emitting elements and brightness degradation> Here, the characteristics and brightness inferiority of a light-emitting element having a fluorescent material and a light-emitting element having a phosphorescent material are discussed. Let's explain the process. First, a light-emitting element (light-emitting element 1) having a fluorescent material, and a phosphorescent material A light-emitting element (light-emitting element 2) having the characteristics of light-emitting element 1 and light-emitting element 2 is fabricated, and the characteristics of light-emitting element 1 and light-emitting element 2 and their brightness are determined. We evaluated the degree of degradation.

[0047] Schematic cross-sectional diagrams of light-emitting element 1 and light-emitting element 2 are shown in Figures 3(A) and 3(B), respectively. Table 1 shows the detailed structure of the second device, and the structures and abbreviations of the compounds used are shown below. (See Figure 3) (A) is a schematic cross-sectional view of the light-emitting element 1, and Figure 3(B) is a schematic cross-sectional view of the light-emitting element 2.

[0048] [ka]

[0049] [ka]

[0050] [Table 1]

[0051] <1-3. Method for fabricating the light-emitting element 1> On the substrate 102, the first electrode 104 is made of silicon, indium, and tin oxide The material (abbreviated as ITSO) was deposited by sputtering. Note that the film of the first electrode 104 The thickness is set to 70 nm, and the area of ​​the first electrode 104 is 4 mm². 2 (2mm x 2mm)

[0052] Next, as a pretreatment before the deposition of the organic compound layer, the first electrode 104 side of the substrate 102 was washed with water and baked at 200 °C for 1 hour. Then, UV ozone treatment was performed on the surface of the first electrode 104 for 370 seconds.

[0053] After that, the substrate 102 was introduced into a vacuum evaporation apparatus whose internal pressure was reduced to about 1×10 -4 Pa. In the heating chamber of the vacuum evaporation apparatus, vacuum baking was performed at 170 °C for 60 minutes, and then the substrate 102 was allowed to cool for about 30 minutes.

[0054] Next, the substrate 102 was fixed to a holder provided in the vacuum evaporation apparatus so that the surface on which the first electrode 104 was formed faced downward. In this embodiment, by the vacuum evaporation method, a hole injection layer 131, a hole transport layer 132, a light-emitting layer 116, an electron transport layer 133, an electron injection layer 134(1 ), an electron injection layer 134(2), and a second electrode 114 were sequentially formed.

[0055] First, after reducing the pressure in the vacuum evaporation apparatus to about 1×10 -4 Pa, on the first electrode 104, as the hole injection layer 131, 3-[4-(9-phenanthryl)-phenyl]-9-phenyl -9H-carbazole (abbreviation: PCPPn) and molybdenum oxide were co-evaporated so that PCPPn: molybdenum oxide = 2:1 (weight ratio). The film thickness of the hole injection layer 131 was set to 20 nm.

[0056] Next, a hole transport layer 132 was formed on the hole injection layer 131. As the hole transport layer 132 , PCPPn was evaporated. The film thickness of the hole transport layer 132 was set to 20 nm.

[0057] ​​​Next, a light-emitting layer 116 was formed on the hole transport layer 132. As the light-emitting layer 116, 7-[4 -(10-phenyl-9-anthryl)phenyl]-7H-dibenzo[c,g]carbazo (abbreviation: cgDBCzPA) and N,N'-bis(3-methylphenyl)-N,N' -Bis[3-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6 -Diamine (abbreviation: 1,6mMemFLPAPrn) and cgDBCzPA:1,6m Co-deposition was performed so that MemFLPAPrn = 1:0.03 (weight ratio). Note that the luminescent layer 1 The film thickness of layer 16 was set to 20 nm. In addition, in the light-emitting layer 116, cgDBCzPA is host The material is 1,6mMemFLPAPrn, and the guest material is 1,6mMemFLPAPrn.

[0058] Next, a 10 nm thick cgDBCzPA layer is added as an electron transport layer 133 on the light-emitting layer 116. The layer was deposited. Next, an electron injection layer 134(1) with a thickness of 15 nm was applied to the electron transport layer 133. Bathophenanthroline (abbreviated as Bphen) was deposited. Next, electron injection layer 134(1) A 1 nm thick layer of lithium fluoride (LiF) was deposited on top as an electron injection layer 134(2). .

[0059] Next, aluminum (Al) is used as the second electrode 114 on the electron injection layer 134(2). The film was deposited. The film thickness of the second electrode 114 was set to 200 nm.

[0060] The light-emitting element on the substrate 102 prepared as described above, and the encapsulating substrate (not shown) are exposed to the atmosphere. To prevent leakage, the glove box was sealed by bonding the parts together in a nitrogen atmosphere. (Apply a sealing material around the element and expose it to 365nm ultraviolet light at 6J / cm² during sealing.) 2 Irradiate, (Heat-treated at 80°C for 1 hour).

[0061] The light-emitting element 1 was fabricated through the above process.

[0062] <1-4. Method for fabricating the light-emitting element 2> ITSO was deposited on the substrate 102 as the first electrode 104 by sputtering. Furthermore, the film thickness of the first electrode 104 is set to 70 nm, and the area of ​​the first electrode 104 is set to 4 mm². 2 ( (2mm x 2mm)

[0063] Next, as a pretreatment before deposition of the organic compound layer, the first electrode 104 side of the substrate 102 is treated with water. After washing and firing at 200°C for 1 hour, the surface of the first electrode 104 is subjected to UV ozone treatment. I did that for 370 seconds.

[0064] Then, 1 × 10 -4 The substrate 102 is introduced into a vacuum deposition apparatus where the internal pressure has been reduced to approximately Pa. Then, in the heating chamber of the vacuum deposition apparatus, vacuum firing is performed at 170°C for 60 minutes, and then the substrate I allowed 102 to cool for about 30 minutes.

[0065] Next, the substrate 102 is vacuum deposited so that the surface on which the first electrode 104 is formed faces downwards. It was fixed in a holder provided inside the device. In this embodiment, hole injection was performed by vacuum deposition. Layer 131, hole transport layer 132, light-emitting layer 116(1), light-emitting layer 116(2), electron transport layer 1 33. The electron injection layer 134(1), electron injection layer 134(2), and second electrode 114 are formed sequentially. did.

[0066] First, inside the vacuum deposition apparatus, 1 × 10 -4 After reducing the pressure to Pa, a hole is placed on the first electrode 104. As the injection layer 131, 4,4',4''-(benzene-1,3,5-triyl)tri(di Benzothiophene (abbreviation: DBT3P-II) and molybdenum oxide are combined in DBT3P-I I:Molybdenum oxide was co-deposited in a ratio of 2:1 (by weight). Note that hole injection layer 13 The film thickness of sample 1 was set to 20 nm.

[0067] Next, a hole transport layer 132 was formed on the hole injection layer 131. , 9-phenyl-9H-3-(9-phenyl-9H-carbazole-3-yl)carbaz A layer of plastic (abbreviated as PCCP) was deposited. The thickness of the hole transport layer 132 was set to 20 nm.

[0068] Next, a light-emitting layer 116(1) was formed on the hole transport layer 132. PCCP and 3,5-bis[3-(9H-carbazole-9-yl)phenyl]pyri Zin (abbreviation: 3,5DCzPPy) and Tris{2-[5-(2-methylphenyl)-4 -(2,6-diisopropylphenyl)-4H-1,2,4-triazole-3-yl- [κN2]phenyl-κC}iridium(III) (abbreviation: Ir(mpptz-diPrp) )3) and PCCP:3,5DCzPPy:Ir(mpptz-diPrp)3=1: Co-deposition was performed in a ratio of 0.3:0.06 (by weight). The film thickness of the light-emitting layer 116(1) was The wavelength was set to 30 nm. In addition, in the light-emitting layer 116(1), PCCP is the host material, 3 ,5DCzPPy is the assisting material, and Ir(mpptz-diPrp)3 is the guest material. It is a fee.

[0069] Next, a light-emitting layer 116(2) was formed on the light-emitting layer 116(1). Then, 3,5DCzPPy and Ir(mpptz-diPrp)3 are combined into 3,5DCzP Co-deposited Py:Ir(mpptz-diPrp)3 = 1:0.06 (weight ratio) The film thickness of the light-emitting layer 116(2) was set to 10 nm. Therefore, 3,5DCzPPy is the host material, and Ir(mpptz-diPrp)3 is the gateway material. It is a material.

[0070] Next, an electron transport layer 133 with a film thickness of 10 nm and a 3.5 DC Hz luminescent layer 116(2) is added on top of the light-emitting layer 116(2). PPy was deposited. Next, an electron injection layer 134(1) was applied to the electron transport layer 133, with a film thickness of 1 A 5nm Bphen layer was deposited. Next, an electron injection layer 134(1) was deposited on top of the electron injection layer 134( 2) A 1 nm thick layer of LiF was deposited.

[0071] Next, aluminum (Al) is used as the second electrode 114 on the electron injection layer 134(2). The film was deposited. The film thickness of the second electrode 114 was set to 200 nm.

[0072] The light-emitting element on the substrate 102 prepared as described above, and the encapsulating substrate (not shown) are exposed to the atmosphere. To prevent leakage, the glove box was sealed by bonding the parts together in a nitrogen atmosphere. The sealing method was the same as that used for light-emitting element 1.

[0073] The light-emitting element 2 was fabricated using the above process.

[0074] In addition, in the deposition process of the light-emitting element 1 and light-emitting element 2 described above, the deposition method is resistive deposition. A heat method was used.

[0075] <1-5. Characteristics of Light-Emitting Element 1 and Light-Emitting Element 2> Next, the characteristics of the fabricated light-emitting elements 1 and 2 were measured. Measurements of light-emitting elements 1 and 2 were performed at room temperature (in an atmosphere maintained at 25°C).

[0076] Figure 4(A) shows the current efficiency-current density characteristics of light-emitting element 1 and light-emitting element 2. Figure 4(B) shows the external quantum efficiency-current density characteristics of element 1 and light-emitting element 2. The current density of child 1 and light-emitting element 2 is 5 mA / cm². 2 Main of light-emitting element 1 and light-emitting element 2 at that time The device characteristics are shown in Table 2.

[0077] [Table 2]

[0078] In Table 2, CE stands for Current Efficiency. ) represents the external quantum efficiency (EQE: External Quantum Eff Chromaticity is represented by the chromaticity coordinates in the CIE 1976 chromaticity system. vinegar.

[0079] As shown in Figures 4(A) and 4(B) and Table 2, the light-emitting element (light-emitting element 2) having a phosphorescent material is Compared to a light-emitting element having a fluorescent material (light-emitting element 1), the current efficiency is 4.3 times higher, and external quantity The efficiency is 2.3 times higher. Thus, the light-emitting element (light-emitting element 2) having phosphorescent material is like a firefly. It has higher luminescence efficiency than a light-emitting element (light-emitting element 1) that has an optical material.

[0080] Furthermore, 2.5 mA / cm² is supplied to light-emitting elements 1 and 2. 2 When current flows at this current density The emission spectrum is shown in Figure 5.

[0081] As shown in Figure 5 and Table 2, light-emitting elements 1 and 2 emit light in the blue wavelength region. It has a peak in the light emission color emitted from light-emitting element 1 and light-emitting element 2. The emitted light color is the same color or a similar color. Note the emission spectrum of the light-emitting element 1. The peak of the emission spectrum of light-emitting element 2 was 465 nm, and the peak of the emission spectrum of light-emitting element 2 was 476 nm. In other words, the fluorescent material exhibited shorter wavelength emission than the phosphorescent material, and also, The difference in optical peaks is 11 nm.

[0082] <1-6. Brightness degradation of light-emitting element 1 and light-emitting element 2> Next, the brightness degradation of light-emitting elements 1 and 2 was evaluated. Evaluation of Brightness Degradation The method involves setting the light-emitting element 1 to 36.3 mA / cm². 2 (Initial brightness = 4930 cd / m²) 2 )of The current density of the light-emitting element 2 was 2.03 mA / cm². 2 (Initial brightness = 1270 cd / m²) 2 ) Each was driven with a constant current based on the current density.

[0083] The evaluation results of brightness degradation are shown in Figure 6. In Figure 6, the vertical axis represents the initial brightness as 100%. The horizontal axis represents the normalized brightness (%), and the horizontal axis represents the element's operating time (h).

[0084] As shown in Figure 6, the light-emitting element (light-emitting element 1) having a fluorescent material has a phosphorescent material Compared to the optical element (light-emitting element 2), the normalized brightness degrades more slowly. In other words, it has a fluorescent material. The light-emitting element (light-emitting element 1) has a longer lifespan than the light-emitting element (light-emitting element 2) which has a phosphorescent material. stomach.

[0085] In Figure 6, a light-emitting element (light-emitting element 1) having a fluorescent material and a phosphorescent material are shown. The light-emitting element (light-emitting element 2) was driven with different current densities, in other words, different brightness levels, but When driven at a brightness level, the light-emitting element (light-emitting element 1) having a fluorescent material has a phosphorescent material It can be seen that it has a much longer lifespan than the light-emitting element (light-emitting element 2).

[0086] As described above, light-emitting devices having phosphorescent materials are more efficient than light-emitting devices having fluorescent materials. The price is high but the lifespan is short. Also, light-emitting devices with fluorescent materials are better than light-emitting devices with phosphorescent materials. It's less efficient but has a longer lifespan.

[0087] Therefore, as a light-emitting element according to one aspect of the present invention, a light-emitting layer having a fluorescent material and a phosphorescent material By stacking it with a light-emitting layer, a highly efficient and long-life light-emitting element can be realized. Yes, it is possible. Furthermore, it is preferable that the fluorescent material and the phosphorescent material emit light of the same color or a similar color. For example... For example, the emission spectrum emitted from an emission layer having a fluorescent material, and the emission layer having a phosphorescent material The difference between the emission spectrum emitted from and the peak value of is within 30 nm, preferably 20 nm. The wavelength is within m, more preferably within 15 nm. Also, fluorescent materials emit more light than phosphorescent materials. For reliability reasons, it is preferable that the light wavelength is located on the shorter wavelength side. Furthermore, the difference in emission peak values ​​is... It is preferable that the wavelength is 5 nm or greater.

[0088] <1-7. Calculation results of initial characteristics> Here, an embodiment of the present invention is a light-emitting element, namely a light-emitting layer having a fluorescent material and a phosphorescent material Regarding the initial characteristics of a light-emitting element (hereinafter referred to as light-emitting element 3) in which a light-emitting layer having a material is laminated: Then, the calculation was performed.

[0089] The calculations were performed under the following three assumptions: (1) A light-emitting layer having a fluorescent material and (2) The exciton generation ratio in the light-emitting layer having a phosphorescent material and the exciton generation ratio in the other layer was set to 0.8:0.2. The lifetime of a light-emitting element with a fluorescent material is inversely proportional to the 1.8 power of its initial brightness, while the lifetime of a light-emitting element with a phosphorescent material is inversely proportional to the 1.8 power of its initial brightness. The lifetime of an optical element is assumed to be inversely proportional to the square of its initial brightness (however, in many cases, this is the case). Since the luminance acceleration coefficient is larger for phosphorescent materials, in one embodiment of the present invention, the luminance acceleration coefficient is (It is preferable that the phosphorescent material is larger than the fluorescent material.) (3) The shape of the brightness degradation curve is The initial brightness was assumed to be the same regardless of the initial brightness. Furthermore, the exciton generation ratio was limited to the above ratio. This does not mean that the ratio is fixed, and the implementer can adjust it to the optimal ratio as appropriate.

[0090] The calculation results are shown in Table 3. Table 3 shows the calculation results for the main element characteristics of the light-emitting element 3.

[0091] [Table 3]

[0092] The element characteristics of the light-emitting element 3 are based on the element characteristics of light-emitting elements 1 and 2 shown in Table 2. The calculation was performed as follows. Furthermore, the efficiency of the light-emitting element 3 (current efficiency and external quantum efficiency) is determined by the following formula. It is possible.

[0093]

number

[0094] The brightness of the light-emitting element 3 can also be calculated in the same way. That is, the brightness shown in Table 3 The brightness of the light element 3 is equal to the brightness of the light-emitting element 1 (700 cd / m²). 2 The brightness (56) is obtained by multiplying ) by 0.8. 0 cd / m 2 ) and the brightness of the light-emitting element 2 (3000 cd / m²) 2 The brightness (6) is obtained by multiplying ) by 0.2. 00 cd / m 2 ) plus the value (1160 cd / m²) 2 ) Furthermore, in Table 3, The brightness of the light-emitting layer having a fluorescent material is defined as the fluorescence brightness, and the brightness of the light-emitting layer having a phosphorescent material is defined as the phosphorescent brightness. Each is expressed as luminance.

[0095] From the results shown in Tables 2 and 3, the current efficiency of light-emitting element 3 is 1.7 compared to light-emitting element 1. It can be seen that the external quantum efficiency improves by a factor of 1.3.

[0096] <1-8. Calculation results of brightness degradation> Next, the light-emitting elements 1 to 3 described above are emitting 1160 cd / m² 2 Degradation when driven by The curve was calculated. The calculation results are shown in Figure 7.

[0097] The brightness degradation curve of the light-emitting element 1 shown in Figure 7 is obtained by subtracting the brightness degradation curve of the light-emitting element 1 shown in Figure 6 from (4 930 / 1160) 1.8 The brightness degradation curve of the light-emitting element 2 shown in Figure 7 is doubled, and is shown in Figure 6. The brightness degradation curve of light-emitting element 2 is (1270 / 1160). 2 It was doubled. Also, the brightness of the light-emitting element 3 The degradation curve is 560 cd / m² for light-emitting element 1. 2 The brightness degradation curve assuming it was driven by, and Optical element 2 at 600 cd / m² 2 The brightness degradation curve assuming it was driven by the same method as above The calculation was performed using [the specified method], and these two brightness degradation curves were added together.

[0098] As shown in Figure 7, the brightness is 80% of the initial brightness, i.e., 928 cd / cm². 2 Until The operating times are approximately 6000h for light-emitting element 1, approximately 220h for light-emitting element 2, and for light-emitting element 3. This is approximately 2000 hours. In other words, the lifespan of the light-emitting element 3 is approximately 1 / It is 3, which is approximately 9 times greater than that of light-emitting element 2.

[0099] Here, Table 4 shows the results when the device characteristics of the light-emitting element 1 and the light-emitting element 2 are normalized by the light-emitting element 3 ( normalized CE, normalized EQE, and normalized lifetime). In Table 4, the normalized lifetime (LT80) is the time when the luminance becomes 80% of the initial luminance when the initial luminance is 100%.

[0100]

Table 4

[0101] As shown in Table 4, it can be seen that the light-emitting element 3, which is one aspect of the present invention, is more efficient than the light-emitting element 1 and has a longer lifetime than the light-emitting element 2. Particularly regarding the lifetime of the light-emitting element 3, it has a lifetime 9 times longer than that of the light-emitting element 2 using only the phosphorescent material. Although the luminous efficiency decreases by only about 60% in terms of CE and 45% in terms of EQE, it can be seen that the effect of extending the lifetime is significant. This can be said to be an unexpected effect, and the reason is considered to be that the differences in the luminance (current) acceleration coefficients between phosphorescence and fluorescence and the differences in current efficiency affect each other. Also, the luminous efficiency is higher than that of the light-emitting element 1 using only the fluorescent material at least. That is, the light-emitting element of one aspect of the present invention can obtain a higher luminous efficiency in principle than the light-emitting element using only the fluorescent material while sufficiently ensuring the lifetime required for the product while using the blue phosphorescent material.

[0102]

[0103] From the calculation results this time, the exciton generation ratio between the fluorescent emission layer and the phosphorescent emission layer is preferably in the range of fluorescence:phosphorescence = 0.9:0.1 or more and 0.5:0.5 or less.

[0103] <1-9. Explanation of the components of the light-emitting element> Next, details of the components of the light-emitting element 100 shown in Figures 1(A)(B) and 2(A)(B) I will explain this.

[0104] [substrate] The substrate 102 is used as a support for the light-emitting element 100. For example, the substrate 102 is... Glass, quartz, or plastic can be used. Furthermore, a flexible substrate can be used. That is also fine. A flexible substrate is a substrate that can be bent (flexible), for example For example, a plastic made of polycarbonate, polyarylate, and polyethersulfone. Examples include substrates, etc. Also, films (polypropylene, polyester, polyvinyl fluoride) Inorganic vapor-deposited films (made of materials such as polyvinyl chloride) can also be used.

[0105] Furthermore, as long as it functions as a support in the manufacturing process of the light-emitting element 100, the above External materials are also acceptable. For example, the light-emitting element 100 can be formed using various substrates. The type of substrate is not limited to a specific type. One example of a substrate is a semiconductor substrate. (For example, single crystal substrates or silicon substrates), SOI substrates, glass substrates, quartz substrates, plastic Bases having stainless steel substrates, metal substrates, stainless steel substrates, and stainless steel foil Plate, tungsten substrate, substrate having tungsten foil, flexible substrate, bonded Examples include film, paper containing fibrous materials, or base film. A glass substrate is one example. These are barium borosilicate glass, aluminoborosilicate glass, or soda-lime glass. Examples include the following: Flexible substrates, laminated films, and base films. Examples include polyethylene terephthalate (PET) and polyethylene naphth. Thalate (PEN), polyethersulfone (PES), polytetrafluoroethylene There are plastics such as PTFE. Alternatively, as an example, acrylic and other alloys... Examples include molded resins, or, for instance, polypropylene, polyester, and polyfluorinated resins. Examples include vinyl or polyvinyl chloride. Alternatively, one example is polyamide, polyimi. These include materials such as d, aramid, epoxy, inorganic vapor-deposited films, or paper.

[0106] Furthermore, a flexible substrate is used as the substrate, and the light-emitting element 100 is formed directly on the flexible substrate. Alternatively, a release layer may be provided between the substrate and the light-emitting element 100. After partially or completely completing the light-emitting element 100 on the substrate, it is separated from the substrate and transferred to another substrate. It can be used for mounting. In this case, even substrates with poor heat resistance or flexible substrates can be used to mount light-emitting elements. Sub-item 100 can be reproduced. The above-mentioned release layer may include, for example, a tungsten film and silica oxide. The structure of a laminated inorganic film with an organic resin film, or a structure in which an organic resin film such as polyimide is formed on a substrate. You can use the suffix, etc.

[0107] In other words, a light-emitting element 100 is formed using one substrate, and then another light-emitting element 10 is formed on another substrate. 0 may be transposed and the light-emitting element 100 may be placed on another substrate. Examples of substrates include, in addition to the substrates mentioned above, paper substrates, cellophane substrates, and aramid film substrates. Substrates: Polyimide film substrates, stone substrates, wood substrates, fabric substrates (natural fibers (silk, cotton, hemp)). ), synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate) (including cupro, rayon, recycled polyester, etc.), leather substrate, or rubber substrate, etc. There are. By using these substrates, a light-emitting element 100 that is difficult to break, a light-emitting element 100 with high heat resistance, a light-emitting element 100 with reduced weight, or a light-emitting element 100 with reduced thickness can be obtained. It can be done.

[0108] [Pair of electrodes] For the first electrode 104 and the second electrode 114, metals, alloys, and electrically conductive compounds, or mixtures thereof can be used. Specifically, oxides having indium and tin (typically, ITO: Indium Tin Oxide), silicon, oxides having indium and tin (ITSO), indium, zinc, tungsten, zinc, oxides having gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), titanium (Ti), and other elements belonging to Group 1 or Group 2 of the periodic table, that is, alkali metals such as lithium (Li) and cesium (Cs), alkaline earth metals such as calcium (Ca) and strontium (Sr), and magnesium (Mg), and alloys containing these (Mg-Ag, Al-Li), rare earth metals such as europium (Eu) and ytterbium (Yb) and alloys containing these, and other materials such as graphene can be used. Note that the first electrode 104 and the second electrode 114 can be formed by, for example, sputtering or vapor deposition (including vacuum vapor deposition).

[0109] In addition, the first electrode 104 and the second electrode 114 have light transmittance for one or both of them so that light emission from the EL layer 108 can be extracted to the outside.

[0110] ​​​​​​​​​​​​​​[First light-emitting layer] The fluorescent material of the first light-emitting layer 110 has a peak in the blue wavelength region of its emission spectrum. It is preferable that the material has the following properties. However, the fluorescent material of the first light-emitting layer 110 may have the following properties. Materials having emission spectral peaks in the green, yellow, or red wavelength range, without limitation. You may use it.

[0111] The fluorescent material for the first light-emitting layer 110 is a pyrene derivative, anthracene derivative, or truffle. phenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, Dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives Examples include conductors, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives. Pyrene derivatives are particularly preferred because they have a high luminescence quantum yield. Specific examples of pyrene derivatives include: N,N'-bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H- Fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemF) LPAPrn), N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H- Fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAP) rn), N,N'-bis(dibenzofuran-2-yl)-N,N'-diphenylpyrene- 1,6-diamine (1,6FrAPrn), N,N'-bis(dibenzothiophen-2- Il)-N,N'-diphenylpyrene-1,6-diamine (abbreviation: 1,6ThAPrn) These are some examples.

[0112] The host material for the first light-emitting layer 110 may be an anthracene derivative or tetracene. Derivatives are preferred because they have a large S1 level and a small T1 level. Specifically, 9-phenyl-3-[4-(10-phenyl-9-antryl)phenyl] -9H-carbazole (PCzPA), 3-[4-(1-naphthyl)-phenyl]-9- Phenyl-9H-carbazole (PCPN), 9-[4-(10-phenyl-9-ant) [Racenyl)phenyl]-9H-carbazole (CzPA), 7-[4-(10-phenyl] -9-Anthryl)phenyl]-7H-dibenzo[c,g]carbazole (cgDBCz PA), 6-[3-(9,10-diphenyl-2-anthryl)phenyl]-benzo[b ]Naphtho[1,2-d]furan (2mBnfPPA), 9-phenyl-10-{4-(9 (-phenyl-9H-fluoren-9-yl)-biphenyl-4'-yl}-anthracene Examples include (FLPPA). Alternatively, 5,12-diphenyltetracene, 5,1 Examples include 2-bis(biphenyl-2-yl)tetracene.

[0113] [Second light-emitting layer] As the phosphorescent material for the second light-emitting layer 112, the emission spectrum peak is in the blue wavelength region. It is preferable that the material has the following properties. However, the phosphorescent material of the second light-emitting layer 112 may have the following properties. Materials having emission spectral peaks in the green, yellow, or red wavelength range, without limitation. You may use it.

[0114] The phosphorescent material for the second light-emitting layer 112 may be iridium, rhodium, or a platinum-based material. Examples include organometallic complexes or metal complexes, among which are organoiridium complexes, such as iridium Mu-type orthometallic complexes are preferred. 4H-triazole is a suitable ligand for orthometallation. Ligand, 1H-triazole ligand, imidazole ligand, triazole ligand, pyr Zin ligands, pyrimidine ligands, pyrazine ligands, triazine ligands, quinoline ligands, Alternatively, isoquinoline ligands can be used. As for metal complexes, porphyrin ligands can be used. Examples include platinum complexes having [specific properties].

[0115] A specific example of an organoiridium complex is tris{2-[5-(2-methylphenyl)- 4-(2,6-dimethylphenyl)-4H-1,2,4-triazol-3-yl-κN 2] Phenyl-κC} Iridium(III) (abbreviation: Ir(mpptz-dmp)3), Tris{2-[5-(2-methylphenyl)-4-(2,6-diisopropylphenyl) -4H-1,2,4-triazole-3-yl-κN2]phenyl-κC}iridium ( III) (abbreviation: Ir(mpptz-diPrp)3), Tris{2-[4-(1-Ada Mantyl)-3-methyl-4H-1,2,4-triazole-5-yl-κN]phenyl -κC} Iridium(III) (abbreviation: Ir(Mptz-Adm1)3), Tris{2- [4-(2-adamantyl)-3-methyl-4H-1,2,4-triazole-5-yl -κN]phenyl-κC}iridium(III) (abbreviation: Ir(Mptz-Adm2)3) ), Tris{2-[4-(2-norbornyl)-3-methyl-4H-1,2,4-tria [Zol-5-yl-κN]phenyl-κC}iridium(III) (abbreviation: Ir(Mpt) Iridium complexes having triazole ligands such as z-Nb)3) are preferred for blue phosphorescent materials. It is suitable. Also, tris{3-(2,4,6-trimethylphenyl)-4H-imidazo Iridium(III) (abbreviation: Ir(tmppi)) m)3) and Tris[1-(3,5-diisopropylphenyl)-2-phenyl-1H- Midazole-C2,N] Iridium(III) (abbreviation: Ir(biprpim)3) Iridium complexes having imidazole ligands can also be used as blue phosphorescent materials. ru.

[0116] As the host material for the second light-emitting layer 112, in addition to zinc and aluminum-based metal complexes, oxy Sadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives Conductors, dibenzoquinoxaline derivatives, dibenzothiophene derivatives, dibenzofuran derivatives Pyrimidine derivatives, triazine derivatives, pyridine derivatives, bipyridine derivatives, phenan Examples include throline derivatives. Other examples include aromatic amines and carbazole derivatives. These are some examples.

[0117] Furthermore, the assist material for the second light-emitting layer 112 can form an excitation complex with the host material. It is preferable that the combination is such that the emission peak of the excited complex is the triplet M of the phosphorescent material. LCT (Metal to Light Charge Transfer) transition The host material and assist material are positioned so that they overlap with the absorption band on the longest wavelength side, or more specifically, with the longest wavelength side. It is preferable to select a phosphorescent material. This dramatically improves the luminescence efficiency. A photonic element can be provided. However, instead of phosphorescent material, thermally activated delayed fluorescence (Ther mally activated delayed fluorescence:TAD F) Materials may be used. TADF materials have limited triplet excitation energy and emission energy. Because they are very close, their behavior in the element is similar to that of phosphorescent materials (for example, phosphorescent materials). For peripheral materials such as the base material, there are cases where blue TADF material is used and cases where blue phosphorescent material is used. (It is necessary to select materials with similarly high triplet excitation energies.) TADF material is used. In such cases, it is preferable that the absorption band on the longest wavelength side is a singlet absorption band. Oh, TADF material is a material that excites a triplet excited state into a singlet excited state with a small amount of thermal energy. Upconversion (reverse intersystem crossing) is possible, and emission (fluorescence) from the singlet excited state can be efficiently performed. This refers to materials that exhibit this phenomenon frequently. Furthermore, the conditions under which thermally activated delayed fluorescence can be efficiently obtained include: The energy difference between the triplet excited level and the singlet excited level is greater than 0 eV and less than or equal to 0.2 eV. A more accurate definition would be a value greater than 0 eV and less than or equal to 0.1 eV.

[0118] [Hole injection layer, hole transport layer] The hole injection layer 131 is transmitted to the first light-emitting layer 110 via a hole transport layer 132 with high hole transport capabilities. This is a layer into which holes are injected, and it is a layer containing a hole transport material and an acceptor material. By including a pore-transporting material and an acceptor material, hole transport is performed by the acceptor material. Electrons are extracted from the material, generating holes, which are then transported through the hole transport layer 132. Holes are injected into the light-emitting layer 110. Alternatively, the hole injection layer 131 is made of a hole transportable material, A laminated structure with an acceptor material may also be used. Note that the hole transport layer 132 is a hole It is formed using transportable materials.

[0119] For example, the hole transport material used in the hole injection layer 131 and the hole transport layer 132 is 4 ,4'-Bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) Or α-NPD) or N,N'-bis(3-methylphenyl)-N,N'-diphenyl- [1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4',4''- Tris(carbazole-9-yl)triphenylamine (abbreviation: TCTA), 4,4', 4''-Tris(N,N-diphenylamino)triphenylamine (abbreviation: TDATA) ,4,4',4''-Tris[N-(3-methylphenyl)-N-phenylamino]tri Phenylamine (abbreviation: MTDATA), 4,4'-bis[N-(spiro-9,9'-bis Aromatic compounds such as fluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB) Aromatic amine compounds, 3-[N-(9-phenylcarbazole-3-yl)-N-phenyl [amino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-( 9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazo (Abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcal [Bazole-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1), etc. Other examples include 4,4'-di(N-carbazolyl)biphenyl (abbreviation: CBP). , 1,3,5-Tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB) ), 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazeo Carbazole derivatives such as CzPA (abbreviated as CzPA) can be used. The materials are mainly 1x10 -6 cm 2 The material has a hole mobility of / Vs or greater. However, Other materials may be used if they have higher hole transport capabilities than these materials.

[0120] Furthermore, poly(N-vinylcarbazole) (abbreviation: PVK), poly(4-vinyl truffle) Phenylamine (abbreviation: PVTPA), poly[N-(4-{N'-[4-(4-diphenyl [phenylamino]phenyl-N'-phenylamino}phenyl)methacrylamide] (Abbreviation: PTPDMA), poly[N,N'-bis(4-butylphenyl)-N,N'-bi By using polymer compounds such as [phenylbenzidine] (abbreviation: Poly-TPD) It can also be done this way.

[0121] Furthermore, as the acceptor material used in the hole injection layer 131, 7,7,8,8-teto Lacyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), Loranyl, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexacyano Xaazatriphenylene (HAT-CN) contains electron-withdrawing groups (halogen groups or cyano groups). Examples of such compounds include those with multiple complex atoms, such as HAT-CN. Compounds in which an electron-withdrawing group is bonded to the aromatic ring are thermally stable and preferred. Examples include metal oxides. Also, gold belonging to groups 4 through 8 of the periodic table. Examples of oxides in this group include vanadium oxide, niobium oxide, and tan oxide. Tal, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, rhenium oxide are It is preferable due to its high electron-accepting ability. In particular, molybdenum oxide is stable even in the atmosphere. It is preferable because it has low hygroscopicity and is easy to handle.

[0122] The hole injection layer 131 is made by mixing the above-mentioned acceptor material alone or with other materials. It may be formed in this way. In this case, the acceptor material extracts electrons from the hole transport layer, Hole injection is possible into the hole transport layer. The acceptor material extracts electrons to the anode. To transport.

[0123] [Electron transport layer] The electron transport layer 133 is a layer containing a material with high electron transport properties. Alq3, Tris(4-methyl-8-quinolinolato)aluminum (abbreviation: Almq3) , bis(10-hydroxybenzo[h]quinolinato)beryllium (abbreviation: BeBq2), BAlq, Zn(BOX)2, bis[2-(2-hydroxyphenyl)benzothiazolat Metal complexes such as zinc (abbreviation: Zn(BTZ)2) can be used. Also, 2-( 4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadia Zole (abbreviation: PBD), 1,3-bis[5-(p-tert-butylphenyl)-1, 3,4-Oxadiazole-2-yl]benzene (abbreviation: OXD-7), 3-(4-te rt-butylphenyl)-4-phenyl-5-(4-biphenylyl)-1,2,4-tri Azole (abbreviation: TAZ), 3-(4-tert-butylphenyl)-4-(4-ethyl Phenyl)-5-(4-biphenylyl)-1,2,4-triazole (abbreviation: p-EtT) AZ), vasophenanthroline (abbreviation: Bphen), vasocuproin (abbreviation: BCP) ), 4,4'-bis(5-methylbenzoxazole-2-yl)stilbene (abbreviation: B Hetero-aromatic compounds such as zOs can also be used. Additionally, poly(2,5-pyridine) can be used. Diyl) (abbreviation: PPy), poly[(9,9-dihexylfluorene-2,7-diyl) -co-(pyridine-3,5-diyl) (abbreviation: PF-Py), poly[(9,9-geo) Ctylfluorene-2,7-diyl)-co-(2,2'-bipyridine-6,6'-diyl) Polymer compounds such as (abbreviated as PF-BPy) can also be used. The materials used were mainly 1x10 -6 cm 2This material has an electron mobility of / Vs or higher. Any material other than those mentioned above can be used as the electron transport layer 133 if it has higher electron transport capabilities than hole transport. You may use it.

[0124] Furthermore, the electron transport layer 133 is not only a single layer, but also consists of two or more layers made of the above material. It may also be considered as a layered structure.

[0125] [Electron injection layer] The electron injection layer 134 is a layer containing a material with high electron injection capacity. Lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF2) , lithium oxide (LiO x Alkali metals, alkaline earth metals, or similar materials such as ) These compounds can be used. Also, rare earth elements such as erbium fluoride (ErF3) Metal compounds can be used. Also, electride can be used in the electron injection layer 134. Good. As the electride, for example, an electrolytic compound of calcium and aluminum is used. Examples include materials to which the substance has been added in high concentrations.

[0126] Furthermore, the electron injection layer 134 is a composite made by mixing an organic compound and an electron donor. Materials may be used. Such composite materials are created when electrons are released from the organic compound by an electron donor. Therefore, it exhibits excellent electron injection and electron transport properties. In this case, as an organic compound... Preferably, the material is one that is excellent at transporting the generated electrons, specifically, for example, the material described above. The electron transport layer 133 can be composed of materials such as metal complexes or heteroaromatic compounds. The electron donor can be any material that exhibits electron-donating properties towards organic compounds. Alkali metals, alkaline earth metals, and rare earth metals are preferred, as are lithium, cesium, Examples include magnesium, calcium, erbium, and ytterbium. Also, alkalis Lithium oxides and alkaline earth metal oxides are preferred, as are lithium oxides and calcium oxides. Examples include barium oxides. Additionally, Lewis bases such as magnesium oxide can be used. It is also possible to use organic compounds such as tetrathiafulvalene (abbreviated as TTF). It can also be done this way.

[0127] Furthermore, the above-mentioned light-emitting layer, hole transport layer, hole injection layer, electron transport layer, and electron injection layer are, These are sputtering, vapor deposition (including vacuum deposition), and printing (e.g., letterpress printing), respectively. (Intaglio printing, gravure printing, lithographic printing, stencil printing, etc.), inkjet printing, coating It can be formed by methods such as weaving.

[0128] The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments. It is possible.

[0129] (Embodiment 2) In this embodiment, the light-emitting mechanism of the light-emitting element 100 shown in Embodiment 1 is shown in Figure This will be explained using Figures 8 through 10.

[0130] <2-1. Light-emitting mechanism of light-emitting elements> First, the light-emitting mechanism of the light-emitting element 100 will be explained below.

[0131] In one aspect of the present invention, the light-emitting element 100 comprises a pair of electrodes (a first electrode 104 and a second electrode 104 and a second electrode 104). By applying a voltage between electrodes 114, electrons are released from the cathode and holes are released from the anode. ) are each injected into the EL layer 108, and current flows. Then, the injected electrons and positive The pores recombine, allowing the guest material in the first light-emitting layer 110 and the second light-emitting layer 112 to... The material (fluorescent material and phosphorescent material) enters an excited state, and light emission is obtained from the excited guest material. It is possible.

[0132] <2-2. Light emission mechanism of the first light-emitting layer 1> Next, the light-emitting mechanism of the first light-emitting layer 110 of the light-emitting element 100 will be described.

[0133] Figure 8(A) is an example of a schematic cross-sectional view of the first light-emitting layer 110. The light-emitting layer 110 comprises a host material 121 and a guest material 122.

[0134] The host material 121 has a singlet excitation energy level and a triplet excitation energy level. It is preferable that the difference is within 0.2 eV. In particular, the host material 121 is heated at room temperature. It is preferable that the material exhibits delayed activation fluorescence. Note that the host material 121 is a single material. It may be composed of multiple materials. Also, guest material 122 As such, a luminescent organic compound can be used, and as such a luminescent organic compound, a fluorescent material It is preferable that it be a material. In the following description, a fluorescent material is used as guest material 122. Let me explain the configuration.

[0135] Furthermore, light emission from guest material 122 is obtained through the following two processes. (α) Direct recombination process (β1) Energy transfer process

[0136] <2-3.(α) Direct recombination process> Carriers (electrons or holes) recombine in guest material 122, Excited state 2 is formed. At this time, the excited state of guest material 122 is a singlet excited state. At this time, fluorescence emission is obtained. On the other hand, when the excited state of guest material 122 is a triplet excited state It is deactivated by heat.

[0137] In the (α) direct recombination process described above, if the fluorescence quantum efficiency of guest material 122 is high This allows for high luminous efficiency.

[0138] <2-4. (β1) Energy Transfer Process> The carriers recombine in the host material 121, and an excited state is formed in the host material 121. This occurs. At this time, when the excited state of the host material 121 is a singlet excited state, the host material 1 The singlet excitation energy level of 21 is higher than the singlet excitation energy level of guest material 122. If the energy is also high, excitation energy is transferred from the host material 121 to the guest material 122, and the guest material The guest material enters a singlet excited state. Fluorescence is emitted from the guest material 122 in the singlet excited state. Luminescence is obtained. Therefore, the singlet excitation energy level of the host material 121 is the guest It is preferable that the level is higher than the singlet excitation energy level of material 122.

[0139] Furthermore, the transition from the singlet excited state of host material 121 to the triplet excited state of guest material 122 is performed. The energy transfer is from the singlet ground state to the triplet excited state in guest material 122. Since direct transitions are prohibited, this is unlikely to become the primary energy transfer process. Omitted. In other words, as shown in the general formula (G1) below, from the singlet excited state of the host material 121 Therefore, energy transfer to the singlet excited state of guest material 122 is important.

[0140] 1 H * + 1G → 1 H+ 1 G * (G1)

[0141] In addition, in the general formula (G1), 1 H * This represents the singlet excited state of the host material 121. 1 G is This represents the singlet ground state of guest material 122. 1 H is in the singlet ground state of host material 121. To express, 1 G * This represents the singlet excited state of guest material 122.

[0142] Next, to explain the energy transfer process between the host material 121 and the guest material 122, Figure 8(B) shows a schematic diagram illustrating the correlation of energy levels. The notation and symbols are as follows: • Host(121): Host material 121 • Guest (122): Guest material 122 (fluorescent material) ·S H : The lowest level of singlet excitation energy of host material 121 ·T H : The lowest level of triplet excitation energy of host material 121 ·S G : The lowest level of singlet excitation energy of guest material 122 (fluorescent material) ·T G : The lowest level of triplet excitation energy for guest material 122 (fluorescent material)

[0143] Even if the excited state of the host material 121 is a triplet excited state, the S of the host material 121 H but , guest material 122 S G If the value is higher than the following, fluorescence emission is obtained through the following two processes. ru.

[0144] As the first step, as shown in route A1 of Figure 8(B), the T of the host material 121 H From inverse interterm crossover (upconversion), S H Excitation energy is transferred to it.

[0145] The second subsequent step is as shown in route E1 of Figure 8(B), host material 1 21 S H From guest material 122 S G The excitation energy is transferred to the guest material 122. It enters a singlet excited state. Fluorescence is obtained from the guest material 122 in the singlet excited state. It can be done.

[0146] The first and second processes described above can be expressed by the following general formula (G2).

[0147] 3 H * + 1 G → (reverse interterm crossover) → 1 H * + 1 G→ 1 H+ 1 G * (G2)

[0148] In addition, in the general formula (G2), 3 H * This represents the triplet excited state of the host material 121. 1 G is This represents the singlet ground state of guest material 122. 1 H * This is the singlet excited state of host material 121. This represents, 1 H represents the singlet ground state of the host material 121. 1 G * Guest material 122 This represents a singlet excited state.

[0149] As shown in the general formula (G2), the triplet excited state of the host material 121 ( 3 H * ) from the inverse term The singlet excited state of the host material 121 due to the crossover ( 1 H * ) is generated, and then the gues Singlet excited state of material 122 ( 1 G * Energy is transferred to ).

[0150] In the (β1) energy transfer process described above, all energy transfer processes occur efficiently. If so, both the triplet excitation energy and the singlet excitation energy of the host material 121 will be efficiently Often, the singlet excited state of guest material 122 ( 1 G * Because it is converted to ), highly efficient light emission is possible. It becomes Noh.

[0151] However, from the singlet excited state and triplet excited state of the host material 121 to the guest material 122 Before the excitation energy is transferred to the singlet excited state, the host material 121 If ghee is deactivated by releasing light or heat, the luminescence efficiency will decrease. Example For example, as shown by the dashed line B1 in Figure 8(B), the triplet excitation energy of the host material 121 is The lowest level is lower than the lowest level of the triplet excitation energy of guest material 122. The substance undergoes the energy transfer process shown in route E3 of Figure 8(B), followed by thermal deactivation. In the case of T H and S H Due to the large energy difference, the reverse interterm crossing of √A1 in Figure 8(B) And the energy transfer process shown in the subsequent route E1 becomes less likely to occur, so guest material The efficiency of generating singlet excited states in material 122 decreases. Therefore, the host material 12 1 T H T is guest material 122 G It is preferable that it is higher than the host material. If 121 is a material that exhibits thermally activated delayed fluorescence, then the thermally activated delayed fluorescence of the host material 121 It is preferable that the luminescence energy of is higher than the phosphorescent luminescence energy of guest material 122. .

[0152] At this time, as shown in the root E2 of Figure 8(B), the T of the host material 121 H From guest materials T G Thermal deactivation also occurs when excitation energy is transferred to the element. Therefore, Figure 8(B The fewer the energy transfer processes shown in route E2, the better the triplet excitation of guest material 122. This is preferable because it can reduce the efficiency of state generation and decrease thermal deactivation. Therefore, it is preferable that the concentration of the guest material 122 relative to the host material 121 be low. Specifically, the concentration of guest material 122 relative to host material 121 is 0 wt%. A value exceeding 5 wt% is preferable, and more preferably exceeding 0 wt% and 1 wt% or less is preferable. It is suitable.

[0153] Furthermore, if the direct recombination process in guest material 122 becomes dominant, the guest material in the emissive layer This results in the generation of numerous triplet excited states (122), which leads to thermal deactivation and a loss of luminescence efficiency. Uh, in other words, the proportion of the (β1) energy transfer process is greater than the (α) direct recombination process mentioned above. A higher amount reduces thermal deactivation that occurs when guest material 122 is in a triplet excited state. This is preferable because it allows for this. For this to happen, the host material 121 is also preferable. A lower concentration of the host material 122 is preferable, specifically, the concentration of the guest material relative to the host material 121. The concentration of material 122 is preferably greater than 0 wt% and less than or equal to 5 wt%, and more preferably The amount is preferably greater than 0 wt% and less than or equal to 1 wt%.

[0154] Next, the governing factors in the energy transfer process between the above-mentioned host material 121 and guest material 122 will be described. As the mechanism of intermolecular energy transfer, there are two proposed mechanisms: the Förster mechanism (dipole-dipole interaction) and the Dexter mechanism (electron exchange interaction).

[0155] <2-5. Förster Mechanism> In the Förster mechanism, energy transfer does not require direct contact between molecules. Energy transfer occurs through the resonance phenomenon of dipole vibrations between the host material 121 and the guest material 122. Due to the resonance phenomenon of dipole vibrations, the host material 121 transfers energy to the guest material 122, the host material 121 returns to the ground state, and the guest material 122 becomes excited. The rate constant k of the Förster mechanism is shown in Equation (1). h*→g h*→g

[0156]

Equation

[0157] In Equation (1), ν represents the frequency, f’(ν) represents the normalized emission spectrum of the host material (when discussing energy transfer from the singlet excited state, it is the fluorescence spectrum; when discussing energy transfer from the triplet excited state, it is the phosphorescence spectrum), ε(ν) represents the molar absorption coefficient of the guest material 122, N represents Avogadro's number, n represents the refractive index of the medium, R represents the intermolecular distance between the host material 121 and the guest material 122, τ represents the measured lifetime of the excited state (fluorescence lifetime or phosphorescence lifetime), and φ represents the emission quantum yield (singlet... h h g g When discussing energy transfer from the singlet excited state, the fluorescence quantum yield, and when discussing energy transfer from the triplet excited state the phosphorescence quantum yield) is represented. K 2 is a coefficient (0 - 4) representing the orientation of the transition dipole moments of the host material 121 and the guest material 122. In the case of random orientation, K 2 = 2 / 3.

[0158] <2-6. Dexter mechanism> In the Dexter mechanism, the host material 121 and the guest material 122 approach the contact effective distance where orbital overlap occurs, and energy transfer occurs through the exchange of electrons between the excited state electrons of the host material 121 and the ground state electrons of the guest material 12 2. The rate constant k of the Dexter mechanism is shown in Equation (2). h*→g is shown in Equation (2).

[0159]

Equation

[0160] In Equation (2), h is Planck's constant, K is a constant with the dimension of energy ν represents the frequency, and f’ h (ν) represents the normalized emission spectrum of the host material 121 (when discussing energy transfer from the singlet excited state, it is the fluorescence spectrum; when discussing energy transfer from the triplet excited state, it is the phosphorescence spectrum), ε’ g (ν) represents the normalized absorption spectrum of the guest material 122, L represents the effective molecular radius, and R represents the intermolecular distance between the host material 121 and the guest material 122.

[0161] Here, the energy transfer efficiency φ from the host material 121 to the guest material 122 ET is It is thought to be expressed by equation (3). k r This is the luminescence process of the host material 121 (singlet excitation state) When discussing energy transfer from states, we discuss energy transfer from fluorescence and triplet excited states. In this case, it represents the rate constant of phosphorescence, and k n This is the non-luminescent process of the host material 121 (thermal deactivation and This represents the rate constant of intersystem crossing, and τ represents the measured lifetime of the excited state of the host material 121. vinegar.

[0162]

number

[0163] From equation (3), the energy transfer efficiency φ ET In order to increase the speed of energy transfer degree constant k h*→g Increase the other competing rate constants k r +k n (=1 / τ) You'll understand that it's better if it's smaller.

[0164] <2-7. Concepts for enhancing energy transfer> In both of the energy transfer processes of the above general equations (G1) and (G2), Singlet excited state of host material 121 ( 1 H * ) from guest material 122 singlet excited state ( 1 G * Since this is an energy transfer to ), the Förster mechanism (equation (1)) and Dexter Energy transfer can occur through both mechanisms (equation (2)).

[0165] First, let's consider energy transfer via the Förster mechanism. From equations (1) and (3) Eliminating τ gives the energy transfer efficiency φ ET The quantum yield φ (energy from singlet excited state) Since we are discussing energy transfer, it can be said that a higher fluorescence quantum efficiency is better. However, in reality, A further important factor is the emission spectrum of the host material 121 (singlet excited state or Since we are discussing their energy transfer, we are comparing the fluorescence spectrum with the absorption spectrum of guest material 122. There is a large overlap with the toll (absorption corresponding to the transition from the singlet ground state to the singlet excited state). This is also necessary. Furthermore, it is preferable that the molar extinction coefficient of guest material 122 is also high. This refers to the emission spectrum of the host material 121 and the longest wavelength side of the guest material 122. This means that the absorption band overlaps with the surrounding area.

[0166] Next, let's consider energy transfer via the Dexter mechanism. According to equation (2), the velocity constant k h*→g To increase the size, the emission spectrum of the host material 121 (from the singlet excited state) Since we are discussing energy transfer, we are comparing the fluorescence spectrum with the absorption spectrum of guest material 122. The greater the overlap with (the absorption corresponding to the transition from the singlet ground state to the singlet excited state) You'll understand the good things.

[0167] From the above, the optimization of energy transfer efficiency is related to the emission spectrum of the host material 121. This is achieved by the overlap of the absorption band that appears on the longest wavelength side of guest material 122. .

[0168] Furthermore, the singlet excitation energy level and the triplet excitation energy level of the host material 121 It is preferable that the difference is within 0.2 eV. With the above configuration, the triple layer of the host material 121 Transitions from singlet excited states to singlet excited states (reverse interterm crossing) are likely to occur. Therefore, The efficiency of generating singlet excited states in the host material 121 can be increased. Furthermore, the host material 121 emission spectra (here, emission of a material having the function of exhibiting thermally activated delayed fluorescence) (spectrum) and appearing on the longest wavelength side of guest material 122, which acts as an energy acceptor. It is preferable that the absorption band and the other overlap. With the above configuration, the singlet excitation of the host material 121 is achieved. Energy transfer from the initial state to the singlet excited state of guest material 122 becomes easier. Therefore, the efficiency of generating singlet excited states of guest material 122 can be increased.

[0169] Furthermore, the triplet excitation energy level of the host material 121 is the triplet excitation energy level of the guest material 122. Because it is higher than the electromotive force level, the host material 121 moves from a triplet excited state to a singlet excited state. Transition to state, and singlet excitation of guest material 122 from the singlet excited state of host material 121. Energy transfer to the state becomes easier. Therefore, thermal deactivation is reduced and luminescence efficiency is increased. It is possible to do so. Furthermore, the host material 121 is a material that exhibits thermally activated delayed fluorescence at room temperature. In this case, the emission energy of the thermally activated delayed fluorescence is equal to the phosphorescence emission energy of the guest material 122. - Because it is higher than - the transition of the host material 121 from the triplet excited state to the singlet excited state, The energy from the singlet excited state of the host material 121 to the singlet excited state of the guest material 122 Energy transfer occurs efficiently. As a result, thermal deactivation is reduced, and luminescence efficiency can be increased. ru.

[0170] <2-8. Light emission mechanism of the first light-emitting layer 2> Next, regarding a light emission mechanism different from <2-2. Light emission mechanism 1 of the first light emission layer>, see Figure 9(A) The following explanation will use (B).

[0171] Figure 9(A) is an example of a schematic cross-sectional view of the first light-emitting layer 110. The light-emitting layer 110 has a host material 121 and a guest material 122. Material 121 comprises a first organic compound 121_1 and a second organic compound 121_2. ru.

[0172] The first organic compound 121_1 and the second organic compound 121_2 form an excited complex (Exc It is preferable that the combination forms an iplex. The excited complex is a singlet complex. The property is that the difference between the excitation energy level and the triplet excitation energy level tends to become very small. Because of this, transitions from triplet excited states to singlet excited states (reverse intersystem crossing) are more likely to occur. i. Also, either the first organic compound 121_1 or the second organic compound 121_2 One of these functions as the host material for the first light-emitting layer 110, and the first organic compound 121_1 also The other half of the second organic compound 121_2 functions as an assisting material for the first light-emitting layer 110. In the following explanation, the first organic compound 121_1 is used as the host material. The explanation will be carried out using the second organic compound 121_2 as an assisting material.

[0173] Furthermore, the first organic compound 121_1 and the second organic compound 121_2 form an excited complex. Even when using host materials that form a combination, the following two conditions apply: Depending on the circumstances, luminescence can be obtained from guest material 122. (α) Direct recombination process (β2) Energy transfer process

[0174] Furthermore, the (α) direct recombination process is the same as the process described in 2-3 above. I will omit the explanation here.

[0175] <2-9. (β2) Energy Transfer Process> A first organic compound 121_1 that forms an excitation complex in the first light-emitting layer 110, and a second The combination with organic compound 121_2 is a combination that can form an excited complex. There are no particular limitations, but one material has hole transport properties and the other has electron transport properties. It is more preferable that the material has a donor-acceptor type excitation state. This makes it easier to form the state, and allows for the efficient formation of excited complexes. By combining a material with pore transport properties and a material with electron transport properties, the first organic compound When constructing a combination of compound 121_1 and a second organic compound 121_2, the mixing ratio This allows for easy control of the carrier balance. Specifically, it has hole transport properties. Materials: Materials with electron transport properties = preferably in the range of 1:9 to 9:1 (by weight). Having this configuration makes it easy to control the career balance, thus reconnecting Control of the overlapping region can also be done easily.

[0176] Furthermore, it is formed by the first organic compound 121_1 and the second organic compound 121_2. The difference between the singlet and triplet excitation energy levels of the excited complex is 0.2 eV. It is preferable that it be within the range described above. With the above configuration, the triplet excitation energy level of the excited complex is Therefore, a transition to the singlet excitation energy level is likely to occur. The efficiency of generating singlet excited states in the host material 121 can be increased. Furthermore, the host material Emission spectrum of material 121 (here, the first organic compound 121_1 and the second organic compound (Emission spectrum of the excited complex formed by substance 121_2 and the guest material 122) It is preferable that the absorption band appearing on the longer wavelength side overlaps with the host material. Energy transfer occurs from the singlet excited state of material 121 to the singlet excited state of guest material 122. This makes it easier. Therefore, to increase the efficiency of generating singlet excited states of guest material 122. This allows for increased luminescence efficiency.

[0177] To explain the energy transfer process of the excited complex, Figure 9(B) shows the energy levels. A schematic diagram illustrating the correlation of the positions is shown. Note that the notation and symbols in Figure 9(B) are as follows: It is. • Host(121): Host material 121 • Guest (122): Guest material 122 (fluorescent material) ·S H : The lowest level of singlet excitation energy of host material 121 ·T H : The lowest level of triplet excitation energy of host material 121 ·S E : The lowest level of singlet excitation energy of the excited complex ·T E : The lowest level of triplet excitation energy of the excited complex ·S G : The lowest level of singlet excitation energy of guest material 122 (fluorescent material) ·T G : The lowest level of triplet excitation energy for guest material 122 (fluorescent material)

[0178] When the carrier is transported to the first light-emitting layer 110, the first organic compound 121_1 and the second The organic compound 121_2 has one side that accepts a hole and the other side that accepts an electron, forming a cation and anion. When they come into close proximity, they quickly form an excited complex. Alternatively, when one enters an excited state, the other... It interacts with the exciton to form an excited complex. Therefore, the exciton in the first light-emitting layer 110 Most of them exist as excited complexes. The excited complexes are the first organic compound 121_1 and Since the band gap will be smaller than that of both of the two organic compounds 121_2, one of the hoses The driving voltage can be lowered by the formation of an excited complex through the recombination of electrons of one electron and the other. can.

[0179] As shown in Figure 9(B), the host material 121 has a first organic compound 121_1 and a second Organic compound 121_2 forms an excited complex with the two organic compounds. In this case, a donor-acceptor type is formed. This allows the excited state of the excited complex to be formed, E and the T of the excited complex E teeth They are in close proximity to each other.

[0180] When the excited state of the excited complex is a singlet excited state, as shown in the root E4 of Figure 9(B), S in excited complex E From guest material 122 S G The excitation energy is transferred to guest material 12 2 enters a singlet excited state. Fluorescence is emitted from guest material 122 in the singlet excited state. It is obtained. In other words, as shown in the general formula (G3) below, from the singlet excited state of the excited complex, the guest Energy transfer occurs to the singlet excited state of material 122.

[0181] 1 [HA] * + 1 G → 1 H+ 1 A+ 1 G * (G3)

[0182] In addition, in the general formula (G3), 1 [HA] * This is the first organic compound 121_1 and the second organic This represents the singlet excited state of the excited complex formed with compound 121_2. 1 G is guest material 1 This represents the singlet ground state of 22, 1H represents the singlet ground state of the first organic compound 121_1. death, 1 A represents the singlet ground state of the second organic compound 121_2, 1 G * Guest material 1 This represents the 22 singlet excited states.

[0183] Furthermore, even if the excited state of the excited complex is a triplet excited state, the S of the excited complex E However, guest material Price 122 S G If the value is higher than the following, fluorescence emission is obtained through the following two processes.

[0184] As the first step, as shown in route A2 of Figure 9(B), the T of the excited complex E From the inverse term Through inter-crossing (upconversion), S E Excitation energy is transferred to it.

[0185] As the second subsequent step, as shown in route E4 of Figure 9(B), the S of the excited complex E From guest material 122 S G The excitation energy is transferred, and guest material 122 undergoes singlet excitation. The system enters an excited state. Fluorescence is obtained from guest material 122, which is in a singlet excited state.

[0186] Furthermore, the processes of Route A2 and Route E4 described above are referred to in this specification, etc., as ExSET. (Exciplex-Singlet Energy Transfer) or Ex The area referred to as EF (Exciplex-Enhanced Fluorescence) There is a match.

[0187] The first and second processes described above can be expressed by the following general formula (G4).

[0188] 3 [HA] * +1 G → (reverse interterm crossing) → 1 [HA] * + 1 G→ 1 H+ 1 A+ 1 G * (G4)

[0189] In addition, in the general formula (G4), 3 [HA] * This is the first organic compound 121_1 and the second organic This represents the triplet excited state of the excited complex formed with compound 121_2. 1 G is guest material 1 This represents the singlet ground state of 22, 1 [HA] * The first organic compound 121_1 and the second organic compound This represents the singlet excited state of the excited complex formed with compound 121_2. 1 H is the first organic This represents the singlet ground state of compound 121_1. 1 A is the singlet form of the second organic compound 121_2. Represents the ground state, 1 G * This represents the singlet excited state of guest material 122.

[0190] As shown in the general formula (G4), the triplet excited state of the excited complex ( 3 [HA] * ) from the inverse term Crossover leads to the singlet excited state of the excited complex ( 1 [HA] * ) is generated, and then, Singlet excited state of material 122 ( 1 G * Energy is transferred to ).

[0191] By configuring the host material 121 as described above, the (β2) energy transfer process described above becomes effective. It occurs efficiently, and both the singlet and triplet excitation energies of the excited complex are efficiently obtained. Because the guest material 122 is converted to a singlet excited state, the guest material of the first light-emitting layer 110 This makes it possible to efficiently obtain light emission from material 122 (fluorescent material).

[0192] However, before the excitation energy is transferred from the excited complex to the guest material 122, the excited complex If the excitation energy is released as light or heat and the element becomes inactive, the luminescence efficiency decreases. There are cases where this occurs. For example, as shown in the root E5 of Figure 9(B), the T of the excited complex E From guests Material 122 T G When excitation energy is transferred to the host material, it undergoes thermal deactivation. Therefore, the host material The preferred concentration of guest material 122 relative to material 121 is greater than 0 wt% and less than or equal to 5 wt%. Suitable, and more preferably, greater than 0 wt% and less than or equal to 1 wt%.

[0193] Furthermore, as shown by the dashed line B2 in Figure 9(B), the T of the host material 121 H , that is, the first The triplet excitation energy levels of organic compound 121_1 or the second organic compound 121_2 are , the T of the excited complex E If it is lower than this, the energy transfer process shown in route E6 in Figure 9(B) After this, it is inactivated by heat. Therefore, the first organic compound 121_1 and the second organic compound The triplet excitation energy level of substance 121_2 is the T of the excited complex. E A higher value is preferable. Furthermore, the excited complex is S E and T E Because they are in close proximity, T E T is a guest material 122 G Lower In that case, S E The energy level of T G It drops significantly to the vicinity or below. As a result, S E From guest material 122 SG Energy transfer to (Route E4) becomes difficult. Therefore, fluorescence from guest material 122 becomes difficult to obtain. Consequently, the T of the excited complex E is, Guess T material 122 G It is preferable that the excited complex is thermally activated at room temperature. If delayed fluorescence is observed, the first organic compound 121_1 and the second organic compound 121_2 The phosphorescence emission energy is higher than the emission energy of the thermally activated delayed fluorescence of the excited complex. This is preferable. Also, the emission energy of the thermally activated delayed fluorescence of the excited complex is the same as that of guest material 122. It is preferable that the phosphorescence emission energy is higher than that of the phosphorescent emission energy.

[0194] The first light-emitting layer 110 is as shown in <2-2. Light-emitting mechanism of the first light-emitting layer 1 >Or use either of the light-emitting mechanisms described in <2-8. Light-emitting mechanism 2 of the first light-emitting layer>. Therefore, it is preferable because it can increase the luminescence efficiency.

[0195] <2-10. Light emission mechanism of the second light-emitting layer> Next, the light-emitting mechanism of the second light-emitting layer 112 of the light-emitting element 100 will be described.

[0196] Figure 10(A) is an example of a schematic cross-sectional view of the second light-emitting layer 112. The second light-emitting layer 112 has a host material 221 and a guest material 222. The material 221 consists of a third organic compound 221_1 and a fourth organic compound 221_2. To possess.

[0197] The second light-emitting layer 112 contains a third organic compound 221_1 and a fourth organic compound 22 1_2 forms an excited complex. Here, the third organic compound 221_1 is used as the host material. Next, we will explain using the fourth organic compound 221_2 as an assisting material.

[0198] The third organic compound 221_1 and the fourth organic compound form an excitation complex in the second light-emitting layer 112. The combination with organic compound 221_2 is a combination that can form an excited complex. It would be ideal if one material had hole transport properties and the other had electron transport properties. It is more preferable that there be a third organic compound 221_1 and the fourth organic compound 22 The combination with 1_2 is the first organic that forms an excitation complex in the first light-emitting layer 110. The combination of compound 121_1 and the second organic compound 121_2 may also have a similar configuration. stomach.

[0199] The third organic compound 221_1 and the fourth organic compound 221 in the second light-emitting layer 112 Figure 10(B) shows the energy level correlation between _2 and guest material 222. Note that Figure 1 The notation and symbols for 0(B) are as follows: • Host(221_1): Host material (third organic compound 221_1) • Assist(221_2): Assist material (4th organic compound 221_2) • Guest (222): Guest material 222 (phosphorescent material) ·S PH : The lowest level of the singlet excited state of the host material (third organic compound 221_1) ·T PH : The lowest level of the triplet excited state of the host material (third organic compound 221_1) ·T PG : The lowest level of the triplet excited state of guest material 222 (phosphorescent material) ·S PE : The lowest level of the singlet excited state of the excited complex ·T PE : The lowest level of the triplet excited state of the excited complex

[0200] As shown in the route E7 of Figure 10(B), the third organic compound 221_1 and the fourth organic compound The lowest level of the singlet excited state of the excited complex is formed by compound 221_2 (S PE ) and the lowest level of the triplet excited state of the excited complex (T PE ) will be adjacent to each other.

[0201] Then, as shown in Figure 10(B) Route E8, the excited complex (S PE ) and (T PE )of The energies of both are set to the lowest level of the triplet excited state of guest material 222 (phosphorescent material) ( T PG Move it to ) to obtain light emission.

[0202] Furthermore, the processes of Route E7 and Route E8 described above are referred to in this specification, etc., as ExTET (Exciplex-Triplet Energy Transfer) There is a match.

[0203] Furthermore, the third organic compound 221_1 and the fourth organic compound 221_2 have a hole in one of them. Then, the other accepts an electron, and they quickly form an excited complex by coming into close proximity. When one of the molecules enters an excited state, it interacts with the other to form an excited complex. Therefore, Most of the excitons in the second light-emitting layer 112 exist as excited complexes. Excited complexes are, Bandgya Because the hole becomes smaller, an excited complex is formed from the recombination of one hole and the electron of the other. This allows the drive voltage to be lowered.

[0204] By configuring the second light-emitting layer 112 as described above, the guest material 22 of the second light-emitting layer 112 This makes it possible to efficiently obtain light emission from 2 (phosphorescent material).

[0205] The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments. It is possible.

[0206] (Embodiment 3) In this embodiment, Figures 11 to 13 show a light-emitting element, which is one aspect of the present invention. Let me explain. Figure 11 is a schematic cross-sectional view illustrating a light-emitting element 150 according to one embodiment of the present invention. Figures 12 and 13 are schematic cross-sectional diagrams illustrating a light-emitting element 150A according to one embodiment of the present invention. ru.

[0207] <3-1. Configuration of light-emitting elements 2> The light-emitting element 150 shown in Figure 11 has multiple electrodes between the first electrode 104 and the second electrode 114. It has several EL layers (first EL layer 141 and second EL layer 142). Either or both of the first and second EL layers 142 are similar to the EL layer 108 shown in Figure 1. It has such a configuration. In other words, the light-emitting element 100 shown in Figure 1 has one EL layer and light-emitting element Child 150 has multiple EL layers. In this specification, the term EL layer refers to at least This is also a layer containing light-emitting material.

[0208] Furthermore, in the light-emitting element 150 shown in Figure 11, the first EL layer 141 and the second EL layer 14 The two layers are stacked, and a charge generation layer is located between the first EL layer 141 and the second EL layer 142. 143 is provided. Note that the first EL layer 141 and the second EL layer 142 have the same configuration. Other configurations are also acceptable.

[0209] The charge generation layer 143 contains a composite material of an organic compound and a metal oxide. For the material, any composite material that can be used in the hole injection layer 131 shown above may be used. Examples of compounds include aromatic amine compounds, carbazole compounds, aromatic hydrocarbons, and polymers. Various compounds can be used, such as oligomers, dendrimers, polymers, etc. Furthermore, as an organic compound, the hole mobility is 1 × 10⁻⁶. -6 cm 2 / Vs or greater It is preferable to apply this. However, if the material has higher hole transport than electron transport, this Other materials may also be used. Composite materials of organic compounds and metal oxides have carrier implantation properties. Because of its excellent carrier transport capabilities, it can achieve low-voltage and low-current operation. Oh, when the anode side of EL layer 141 or EL layer 142 is in contact with charge generation layer 143. This means that the charge generation layer 143 also plays the role of a hole transport layer for the EL layer 141 or EL layer 142. Therefore, it is not necessary to provide a hole transport layer in EL layer 141 or EL layer 142.

[0210] Furthermore, the charge generation layer 143 consists of a layer containing a composite material of an organic compound and a metal oxide, and other materials. It may be formed as a laminated structure by combining layers composed of the following: For example, an organic compound and A layer containing a metal oxide composite material and one compound selected from electron-donating materials and electron transport A layer containing a highly transportable compound may be formed in combination with another layer. A layer containing an oxide composite material may be formed in combination with a transparent conductive film.

[0211] Furthermore, the charge generation layer 143 sandwiched between the first EL layer 141 and the second EL layer 142 is the first When a voltage is applied to the first electrode 104 and the second electrode 114, electrons are injected into one of the EL layers. Any method that injects holes into the other EL layer is acceptable. For example, in Figure 11, the first electric When a voltage is applied such that the potential of electrode 104 is higher than the potential of the second electrode 114 The charge generation layer 143 injects electrons into the first EL layer 141 and holes into the second EL layer 142. Any substance that can be injected will suffice.

[0212] Furthermore, although Figure 11 describes a light-emitting element having two EL layers, there are also three or more. The same method can be applied to light-emitting elements with the upper EL layer stacked on top. As in 150, multiple EL layers are arranged between a pair of electrodes, separated by a charge generation layer 143. This enables high-brightness light emission while maintaining a low current density, and also realizes a long-life element. It is possible to realize a light-emitting device that can be driven at low voltage and consumes low power.

[0213] Furthermore, of the multiple EL layers, at least one EL layer is the EL layer 1 shown in Embodiment 1. Having 08 makes it possible to create a light-emitting element that is highly efficient and has a long lifespan.

[0214] <3-2. Configuration of light-emitting elements 3> Next, a specific example of the light-emitting element 150 shown in Figure 11 will be explained using Figures 12 and 13. To do so.

[0215] The light-emitting element 150A shown in Figure 12 has a first electrode 104 and a second electrode 114 between them. It has a first EL layer 141 and a second EL layer 142. The first EL layer 141 is shown in Figure 12. This has the same configuration as the EL layer 108 shown in Figure 1. Also, the second EL layer 142 shown in Figure 12 This includes a hole injection layer 415, a hole transport layer 416, a third light-emitting layer 444, and an electron transport layer 41 It has 7 and an electron injection layer 418.

[0216] The hole injection layer 415, the hole transport layer 416, the electron transport layer 417, and the electron injection layer 418 are, These are the hole injection layer 131, hole transport layer 132, electron transport layer 133, and electron transport layer, respectively, as shown above. The configuration can be the same as that of the injection layer 134.

[0217] The third light-emitting layer 444 comprises a host material 431 and a guest material 432. The host material 431 consists of a first organic compound 431_1 and a second organic compound 431_2, It possesses. For example, using the first organic compound 431_1 as a host material, and the second organic compound 43 1_2 can be used as an assist material. In this embodiment, the host Material 431 consists of two types of organic compounds (the first organic compound 431_1 and the second organic compound 431_1). Although examples of configurations using item 431_2) have been given, the configuration is not limited to this, and may use one type or three types Materials of a similar or higher grade may also be used.

[0218] As the guest material 432, a phosphorescent material is preferred. Also, as the guest material 432, It is preferable that the first light-emitting layer 110 and the second light-emitting layer 112 have different emission spectral peaks. For example, the first light-emitting layer 110 and the second light-emitting layer 112 and the third light-emitting layer 444 By making the light sources complementary to each other, white light emission can be obtained. For example, The first light-emitting layer 110 and the second light-emitting layer 112 exhibit peaks in their emission spectra in the blue wavelength region. If such a guest material 432 of the third light-emitting layer 444 emits light in the yellow wavelength region. It is preferable to use a material that has spectral peaks.

[0219] Furthermore, the light-emitting element 150A shown in Figure 12 may have the configuration shown in Figure 13.

[0220] The light-emitting element 150A shown in Figure 13 is the second EL layer 14 of the light-emitting element 150A shown in Figure 12. The configuration is different from that of 2. The light-emitting element 150A shown in Figure 13 has a third light-emitting layer 444 on top of it. It has a fourth light-emitting layer 445.

[0221] The fourth light-emitting layer 445 of the second EL layer 142 of the light-emitting element 150A shown in Figure 13 is It comprises a host material 441 and a guest material 442. The host material 441 is a first It comprises an organic compound 441_1 and a second organic compound 441_2. For example, the first Using organic compound 441_1 as the host material and a second organic compound 441_2 as the assist material It can be used in this way.

[0222] As the guest material 442, a phosphorescent material is preferred. Also, as the guest material 442, The first light-emitting layer 110, the second light-emitting layer 112, and the third light-emitting layer 444 are different light-emitting layers It is preferable to have a vector peak. For example, the first light-emitting layer 110 and the second light-emitting layer 11 Layer 2 has an emission spectrum peak in the blue wavelength region, and the third emission layer 444 has a green wavelength. The emission spectrum has peaks in the long wavelength region, and the fourth emission layer 445 emits light in the red wavelength region. It can be configured to have a peak in the vector.

[0223] Furthermore, the third light-emitting layer 444 and the fourth light-emitting layer 445 are the same as the second light-emitting layer 112 shown above. The same materials can be used as those for the light-emitting mechanism and the second light-emitting layer 112.

[0224] The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments. It is possible.

[0225] (Embodiment 4) In this embodiment, a display device having a light-emitting device according to one aspect of the present invention is shown in Figure 14. Then, I will explain.

[0226] <4.Display device> Figure 14(A) is a block diagram illustrating a display device according to one embodiment of the present invention, and Figure 1 4(B) is a circuit diagram illustrating a pixel circuit in a display device according to one aspect of one aspect of the present invention. ru.

[0227] The display device shown in Figure 14(A) has a region having pixels of the display element (hereinafter referred to as the pixel portion 802 and ( ) and a circuit section ( ) which is located outside the pixel section 802 and has a circuit for driving the pixels. Hereinafter referred to as the drive circuit section 804, and a circuit having a function to protect the element (hereinafter referred to as the protection circuit 804) It has a (6) and a terminal section 807. Note that the protection circuit 806 is not provided. That's fine.

[0228] Part or all of the drive circuit section 804 is formed on the same substrate as the pixel section 802. This is desirable. This allows for a reduction in the number of components and terminals. Drive circuit section 804 If part or all of it is not formed on the same substrate as the pixel section 802, the drive cycle Part or all of road section 804 is COG or TAB (Tape Automated B It can be implemented by (onding).

[0229] The pixel section 802 is arranged in X rows (where X is a natural number greater than or equal to 2) and Y columns (where Y is a natural number greater than or equal to 2). It has a circuit for driving multiple display elements (hereinafter referred to as the pixel circuit 801), and the drive cycle The path section 804 is a circuit that outputs a signal (scan signal) for selecting pixels (hereinafter referred to as the gate driver). 804a) is used to supply signals (data signals) for driving the pixel display elements. It has a drive circuit such as the source driver 804b.

[0230] The gate driver 804a has a shift register, etc. The gate driver 804a has, A signal to drive the shift register is input via terminal 807, and the signal is output. For example, the gate driver 804a receives input such as a start pulse signal and a clock signal. The gate driver 804a outputs a pulse signal. The scanning signal is applied to the wiring (and It has the function of controlling the potential of the scan lines (referred to as GL_1 to GL_X) below. Multiple drivers 804a are provided, and multiple gate drivers 804a are used to control the scan line GL_1 The signal to GL_X may be divided and controlled. Alternatively, the gate driver 804a may use an initialization signal. It has the function of supplying, however, the gate driver 80 4a can also supply another signal.

[0231] The source driver 804b has a shift register, etc. The source driver 804b Through terminal 807, in addition to signals for driving the shift register, the data signals are generated. A signal (image signal) is input. The source driver 804b uses the image signal to create a pixel circuit. It has the function of generating data signals to write to 801. Also, source driver 804b The data signal is transmitted according to the pulse signal obtained by inputting the start pulse, clock signal, etc. It has the function of controlling the output of the unit. In addition, the source driver 804b is given a data signal. It has the function of controlling the potential of the wiring (hereinafter referred to as data lines DL_1 to DL_Y). Alternatively, the source driver 804b may have the ability to supply initialization signals. However, this is not limited to the source driver 804b, which may also supply other signals. It is possible.

[0232] The source driver 804b is configured using, for example, multiple analog switches. The source driver 804b sequentially turns on multiple analog switches, The image signal can be time-divided and output as a data signal. It can also use shift registers, etc. You may use this to configure the source driver 804b.

[0233] Each of the multiple pixel circuits 801 receives a scan signal from one of the multiple scan lines GL. A pulse signal is input via one of several data lines DL to which a data signal is supplied. A data signal is input. In addition, each of the multiple pixel circuits 801 is a gate driver. 804a controls the writing and retention of data in the data signal. For example, m rows and n columns. The pixel circuit 801 of the eye is connected to the gate driver via the scan line GL_m (where m is a natural number less than or equal to X). A pulse signal is input from 804a, and the data line DL_n( A data signal is input from the source driver 804b via n (where n is a natural number less than or equal to Y).

[0234] The protection circuit 806 shown in Figure 14(A) is, for example, a gate driver 804a and a pixel circuit 8 It is connected to scan line GL, which is the wiring between 01. Alternatively, protection circuit 806 is connected to source driver It is connected to the data line DL, which is the wiring between the pixel circuit 804b and the pixel circuit 801. The protection circuit 806 is connected to the wiring between the gate driver 804a and the terminal section 807. Yes, it is possible. Alternatively, the protection circuit 806 can provide a connection between the source driver 804b and the terminal section 807. It can be connected to a wire. The terminal 807 is used to supply power and to the display device from an external circuit. This refers to the part equipped with terminals for inputting control signals and image signals.

[0235] The protection circuit 806, when a potential outside a certain range is applied to the wiring to which it is connected, This is a circuit that creates a conductive state between two wires.

[0236] As shown in Figure 14(A), the pixel section 802 and the drive circuit section 804 each have a protection circuit 80 By providing 6, ESD (Electrostatic Discharge: This can improve the resistance of display devices to overcurrents generated by electrostatic discharge, etc. However, the configuration of the protection circuit 806 is not limited to this, for example, the gate driver 804a may be configured as follows: Configuration with protection circuit 806 connected, or with protection circuit 806 connected to source driver 804b. This configuration is also possible. Alternatively, a configuration in which the protection circuit 806 is connected to the terminal 807. It can also be done this way.

[0237] Furthermore, in Figure 14(A), the gate driver 804a and the source driver 804b are Therefore, although an example is shown in which the drive circuit section 804 is formed, the configuration is not limited to this. For example, only the gate driver 804a is formed, and a separately prepared source driver circuit is formed. A substrate (for example, a drive circuit substrate formed from a single-crystal semiconductor film or a polycrystalline semiconductor film) is put into practice. It can also be used as a mounting configuration.

[0238] Furthermore, the multiple pixel circuits 801 shown in Figure 14(A) have, for example, the configuration shown in Figure 14(B). It can be done this way.

[0239] The pixel circuit 801 shown in Figure 14(B) consists of transistors 852 and 854 and a capacitive element 86 It has 2 and a light-emitting element 872.

[0240] One of the source and drain electrodes of transistor 852 is supplied with a data signal. It is electrically connected to the wiring (hereinafter referred to as signal line DL_n). Furthermore, transistor 85 The gate electrode of 2 supplies electrical signals to the wiring to which the gate signal is supplied (hereinafter referred to as scan line GL_m). It connects to the target.

[0241] Transistor 852, by being either on or off, controls the data signal. It has a function to control the writing of data.

[0242] One of the pair of electrodes of the capacitive element 862 is connected to a wiring to which a potential is supplied (hereinafter referred to as the potential supply line VL). It is electrically connected to (a), and the other is the source electrode and drain of transistor 852. It is electrically connected to the other electrode.

[0243] The capacitive element 862 functions as a holding capacitor to retain the written data.

[0244] One of the source and drain electrodes of transistor 854 is connected to the potential supply line VL_a. They are electrically connected. Furthermore, the gate electrode of transistor 854 is connected to the gate electrode of transistor 852. It is electrically connected to the other of the source electrode and drain electrode.

[0245] One of the light-emitting element 872's anode and cathode are electrically connected to the potential supply line VL_b. The other end is electrically connected to the source and drain electrodes of transistor 854. It will be done.

[0246] As the light-emitting element 872, the light-emitting element 100 shown in Embodiment 1 can be used.

[0247] Furthermore, a high power supply potential VDD is supplied to one of the potential supply lines VL_a and VL_b. On the other hand, a low power supply potential VSS is applied.

[0248] In a display device having the pixel circuit 801 shown in Figure 14(B), for example, the ge shown in Figure 14(A) The driver 804a sequentially selects the pixel circuit 801 for each row, and the transistor 852 Turn it on and write the data signal.

[0249] When data is written to the pixel circuit 801, the transistor 852 turns off. It enters a holding state. Furthermore, in accordance with the potential of the written data signal, transistor 854 The amount of current flowing between the source electrode and the drain electrode is controlled, and the light-emitting element 872 controls the amount of current flowing through it. It emits light with brightness corresponding to the flow rate. By performing this sequentially for each row, an image can be displayed.

[0250] Furthermore, the pixel circuit has a function to compensate for the effects of fluctuations in the transistor threshold voltage, etc. This may be done. Figures 15(A)(B) and 16(A)(B) show examples of pixel circuits.

[0251] The pixel circuit shown in Figure 15(A) consists of six transistors (transistors 303_1 to 303_3). It has 03_6), a capacitive element 304, and a light-emitting element 305. Also, Figure 15(A) The pixel circuit shown includes wiring 301_1 to 301_5, as well as wiring 302_1 and wiring 30 2_2 is electrically connected. Regarding transistors 303_1 to 303_6... For example, a P-type polarity transistor can be used.

[0252] The pixel circuit shown in Figure 15(B) is the same as the pixel circuit shown in Figure 15(A), but with transistor 303 This configuration includes the addition of _7. Furthermore, the pixel circuit shown in Figure 15(B) includes wiring 301_6 and Wiring 301_7 is electrically connected. Here, wiring 301_5 and wiring 301_6 These may be electrically connected to each other. Regarding transistor 303_7... For example, a P-type polarity transistor can be used.

[0253] The pixel circuit shown in Figure 16(A) consists of six transistors (transistors 308_1 to 308_3). It has 08_6), a capacitive element 304, and a light-emitting element 305. Also, Figure 16(A) The pixel circuit shown includes wiring 306_1 to 306_3, and wiring 307_1 to 307_ 3 is electrically connected. Here, wiring 306_1 and wiring 306_3 are electrically connected. They may be electrically connected. Regarding transistors 308_1 to 308_6: For example, a P-type polarity transistor can be used.

[0254] The pixel circuit shown in Figure 16(B) consists of two transistors (transistor 309_1 and Rangitator 309_2) and two capacitive elements (capacitive element 304_1 and capacitive element 304_ 2) and a light-emitting element 305 are included. Also, the pixel circuit shown in Figure 16(B) has wiring 3 Wirings 11_1 to 311_3, 312_1, and 312_2 are electrically connected. Furthermore, by using the pixel circuit configuration shown in Figure 16(B), for example, voltage input - power A flow-driven system (also called a CVCC system) can be used. Note that transistor 309_ For 1 and 309_2, for example, a P-type polarity transistor can be used.

[0255] Furthermore, a light-emitting element according to one aspect of the present invention is an active element having an active element in the pixels of a display device. Trix system, or passive matrix system where the pixels of the display device do not have active elements. It can be applied to each method.

[0256] In the active matrix system, the active elements (active elements, nonlinear elements) are, In addition to transistors, various active elements (active elements, nonlinear elements) can be used. This can be done. For example, MIM (Metal Insulator Metal), or T It is also possible to use elements such as FD (Thin Film Diode). Because it involves fewer manufacturing steps, it is possible to reduce manufacturing costs or improve yield. Alternatively, these elements can improve the aperture ratio due to their small size. This allows for lower power consumption and higher brightness.

[0257] Other than the active matrix method, there are active elements (active elements, nonlinear elements) It is also possible to use a passive matrix type that does not use active elements. Because it does not use sub-elements or nonlinear elements, the manufacturing process is simpler, resulting in reduced manufacturing costs or higher yield. This can improve the performance. Alternatively, active elements (active elements, nonlinear elements) can be used. Because it does not exist, the aperture ratio can be improved, leading to lower power consumption or higher brightness. It is possible.

[0258] The configuration shown in this embodiment may be used in appropriate combination with the configurations shown in other embodiments. It is possible.

[0259] (Embodiment 5) In this embodiment, a display panel having a light-emitting device according to one aspect of the present invention, and the display An electronic device with an input device attached to a panel will be explained using Figures 17 to 21. .

[0260] <5-1. Explanation regarding the touch panel 1> In this embodiment, as an example of electronic equipment, a display panel and an input device are combined. This document describes the Touch Panel 2000, which is used in conjunction with the Touch Panel. It also explains the Touch Panel as an example of an input device. The case in which a sensor is used will be explained. Note that the light-emitting device of one embodiment of the present invention is shown on the display panel. It can be used as a base.

[0261] Figures 17(A) and 17(B) are perspective views of the Touch Panel 2000. In section B), for clarity, typical components of the touch panel 2000 are shown.

[0262] The touch panel 2000 has a display panel 2501 and a touch sensor 2595 (Figure See 17(B). Also, the touch panel 2000 is made up of circuit board 2510, circuit board 2570, and It has a substrate 2590. Note that substrates 2510, 2570, and 2590 are all It also has flexibility. However, any of substrates 2510, 2570, and 2590 The configuration may be one or all of which lack flexibility.

[0263] The display panel 2501 has multiple pixels on the substrate 2510 and supplies signals to those pixels. It has multiple wirings 2511 that can do so. The multiple wirings 2511 are located on the outer periphery of the substrate 2510. It is routed to the FPC250, and a portion of it forms terminal 2519. Terminal 2519 is FPC250 Connect electrically to 9(1).

[0264] The circuit board 2590 has a touch sensor 2595 and is electrically connected to the touch sensor 2595. It has multiple wires 2598. The multiple wires 2598 are routed around the outer periphery of the substrate 2590. A portion of it forms a terminal. This terminal is electrically connected to FPC2509(2). The process continues. Note that in Figure 17(B), for clarity, the back side of substrate 2590 (substrate 2510) is shown. The electrodes and wiring of the touch sensor 2595, which is located on the opposite side, are shown with solid lines.

[0265] For example, a capacitive touch sensor can be used as the touch sensor 2595. Capacitive capacitance methods include surface capacitance and projected capacitance.

[0266] Projected capacitance systems are classified into self-capacitance and mutual-capacitance types, mainly based on differences in their driving methods. There are several advantages. Using a mutual capacitance method is preferable because it enables simultaneous multi-point detection.

[0267] Note that the touch sensor 2595 shown in Figure 17(B) is a projected capacitive touch sensor. This configuration applies the "S" principle.

[0268] Furthermore, the touch sensor 2595 can detect the proximity or contact of an object to be detected, such as a finger. Yes, various sensors can be applied.

[0269] The projected capacitive touch sensor 2595 has electrodes 2591 and 2592. Electrode 2591 is electrically connected to one of the multiple wires 2598, and electrode 2592 is Connect electrically to any of the other wires 2598.

[0270] As shown in Figures 17(A) and 17(B), the electrode 2592 is arranged in multiple repeating directions. It has a shape in which the quadrilaterals are connected at their corners.

[0271] Electrode 2591 is quadrilateral and repeats in a direction intersecting the direction in which electrode 2592 extends. It is positioned.

[0272] Wiring 2594 is electrically connected to the two electrodes 2591 that sandwich electrode 2592. A shape that minimizes the area of ​​the intersection between electrode 2592 and wiring 2594 is preferable. This reduces the area where electrodes are not provided, thereby reducing variations in transmittance. Yes, it is possible. As a result, it reduces the variation in brightness of the light transmitted through the touch sensor 2595. It is possible.

[0273] Note that the shapes of electrodes 2591 and 2592 are not limited to these and can take on various shapes. For example, multiple electrodes 2591 are arranged so that there are as few gaps as possible, and an insulating layer is used. Multiple electrodes 2592 are provided spaced apart so that there is a region that does not overlap with electrode 2591. This configuration may also be used. In this case, between the two adjacent electrodes 2592, there is an electrical connection between them. Providing an insulated dummy electrode is preferable because it reduces the area of ​​regions with different transmittances. .

[0274] Note that conductive films such as electrode 2591, electrode 2592, and wiring 2598, i.e., touch panel Materials that can be used for wiring and electrodes that make up the circuit include indium oxide, tin oxide, and acid Examples include transparent conductive films containing zinc oxide (e.g., ITO). Also, touch panels. For example, materials that can be used for the wiring and electrodes that make up the system are preferred if they have a low resistance value. For example, silver, copper, aluminum, carbon nanotubes, graphene, and halogens. Metal halides (such as silver halides) may also be used. Furthermore, extremely thin (for example, Even when using metal nanowires composed of multiple conductors (with a diameter of several nanometers), That's fine. Alternatively, a metal mesh made of conductive material in a network structure may be used. For example, Ag Nanowires, Cu nanowires, Al nanowires, Ag mesh, Cu mesh, Al mesh You may also use materials such as scouring pads. For example, Ag nanowires can be used for the wiring and electrodes that make up a touch panel. When using this, the transmittance in visible light must be 89% or higher, and the sheet resistance must be 40Ω / □ or higher. It can be set to 0Ω / □ or less. Also, the wiring and electrodes that make up the touch panel as described above Examples of materials that can be used include metal nanowires, metal meshes, and carbon nanochips. Tubes, graphene, etc., have high transmittance in visible light, so they are used as electrodes in display elements. For example, it may be used as a pixel electrode or a common electrode.

[0275] <5-2. Explanation of the display panel> Next, we will explain the details of the display panel 2501 using Figure 18(A). A) corresponds to the cross-sectional view between the dashed line X1 and X2 shown in Figure 17(B).

[0276] The display panel 2501 has a plurality of pixels arranged in a matrix. These pixels are used for display It comprises an element and a pixel circuit that drives the display element.

[0277] For example, substrates 2510 and 2570 have a water vapor transmission rate of 10 -5 g / (m 2 (day) or less, preferably 10 -6 g / (m 2 It has flexibility of less than or equal to (day). The material can be suitably used. Alternatively, the thermal expansion coefficient of substrate 2510 and substrate 2570 It is preferable to use a material with a coefficient of thermal expansion that is approximately equal to that of the material. For example, a material with a coefficient of linear expansion of 1 × 10⁻⁶. - 3 / K or less, preferably 5 × 10 -5 / K or less, more comfortable 1×10 -5 / K or less Certain materials can be used suitably.

[0278] The substrate 2510 includes an insulating layer 2510a that prevents the diffusion of impurities to the light-emitting element, and a flexible Adhesive layer 2 for bonding substrate 2510b, insulating layer 2510a, and flexible substrate 2510b It is a laminate having 510c. Furthermore, the substrate 2570 is a substrate that prevents the diffusion of impurities to the light-emitting element. An insulating layer 2570a to prevent leakage, a flexible substrate 2570b, and the insulating layer 2570a and the flexible substrate The laminate has an adhesive layer 2570c that bonds 2570b together.

[0279] Examples of adhesive layers 2510c and 2570c include polyester, polyolefin, etc. Polyamide (nylon, aramid, etc.), polyimide, polycarbonate, or acrylic Materials containing yl resin, polyurethane, epoxy resin, or resin having siloxane bonds. You can use the fee.

[0280] Furthermore, a sealing layer 2560 is provided between substrate 2510 and substrate 2570. (Sealing layer 2560) It is preferable that it has a refractive index greater than that of air. Also, as shown in Figure 18(A), sealing If light is to be extracted to the layer 2560 side, the sealing layer 2560 can also function as an optical element.

[0281] Furthermore, a sealing material may be formed on the outer periphery of the sealing layer 2560. As a result, the region surrounded by substrate 2510, substrate 2570, sealing layer 2560, and sealing material The configuration can include a light-emitting element 2550. Furthermore, the sealing layer 2560 can be... The container may be filled with an active gas (such as nitrogen or argon). Furthermore, a desiccant may be placed inside the inert gas. It may also be configured to adsorb moisture, etc. Furthermore, as the sealing material mentioned above, for example... It is preferable to use epoxy resins or glass frits. Also, the materials used for the sealant For this purpose, it is preferable to use a material that does not permeate moisture or oxygen.

[0282] Furthermore, the display panel 2501 has pixels 2502. Also, pixels 2502 are light-emitting modules. It has a volume of 2580.

[0283] Pixel 2502 is connected to the light-emitting element 2550 and can supply power to the light-emitting element 2550. It has a transistor 2502t. The transistor 2502t is part of the pixel circuit. It functions as a part. In addition, the light-emitting module 2580 consists of a light-emitting element 2550 and a colored layer 25 It has 67R.

[0284] The light-emitting element 2550 has a lower electrode, an upper electrode, and an EL layer between the lower electrode and the upper electrode. It has. As the light-emitting element 2550, for example, the light-emitting element 100 shown in Embodiment 1 is applied. It is possible. However, although only one light-emitting element 2550 is shown in the drawing, Alternatively, the configuration may include two or more light-emitting elements.

[0285] Furthermore, if the sealing layer 2560 is provided on the side from which light is extracted, the sealing layer 2560 is It is in contact with the optical element 2550 and the colored layer 2567R.

[0286] The colored layer 2567R is located in a position that overlaps with the light-emitting element 2550. As a result, the light-emitting element 2 A portion of the light emitted by 550 passes through the colored layer 2567R, and the light emission is directed in the direction of the arrow shown in the figure. It is ejected outside of the Joule 2580.

[0287] Furthermore, the display panel 2501 is provided with a light-shielding layer 2567BM in the direction from which light is emitted. The light-shielding layer 2567BM is provided so as to surround the colored layer 2567R.

[0288] The colored layer 2567R only needs to have the function of transmitting light in a specific wavelength band. For example, a color filter that transmits light in the red wavelength range, and a color filter that transmits light in the green wavelength range. Color filters, color filters that transmit light in the blue wavelength range, color filters that transmit light in the yellow wavelength range Transparent color filters can be used. Each color filter is made from various materials. Using printing methods, inkjet methods, and etching methods using photolithography technology, It can be formed in any way.

[0289] Furthermore, an insulating layer 2521 is provided on the display panel 2501. The insulating layer 2521 is tra It covers the radiator 2502t. The insulating layer 2521 flattens the irregularities caused by the pixel circuit. It has the function to do so. Furthermore, it provides the insulating layer 2521 with a function to suppress the diffusion of impurities. This may be done. This can lead to a decrease in the reliability of transistors such as the 2502t due to the diffusion of impurities. This can suppress it.

[0290] Furthermore, the light-emitting element 2550 is formed above the insulating layer 2521. The lower electrode of 50 is provided with a partition wall 2528 that overlaps the end of the lower electrode. A spacer is formed on the partition wall 2528 to control the distance between substrate 2510 and substrate 2570. You may do so.

[0291] The scan line driving circuit 2503g has a transistor 2503t and a capacitive element 2503c. Furthermore, the drive circuit can be formed on the same substrate using the same process as the pixel circuit.

[0292] Furthermore, wiring 2511 that can supply signals is provided on the circuit board 2510. Furthermore, terminal 2519 is provided on wiring 2511. Also, terminal 2519 has FP C2509(1) is electrically connected. Also, FPC2509(1) receives the video signal. It has the function of supplying clock signals, start signals, reset signals, etc. Note: FPC2 A printed circuit board (PWB) may be attached to 509(1).

[0293] Furthermore, transistors of various structures can be applied to the display panel 2501. Figure 18(A) shows an example of the case where a bottom-gate type transistor is applied. However, it is not limited to this, for example, the top gate type transistor shown in Figure 18(B) The ZISTA may also be configured to be applied to the display panel 2501.

[0294] Furthermore, regarding the polarity of transistors 2502t and 2503t, there are no particular limitations. There is no fixed definition; it is a structure having N-type and P-type transistors, or an N-type transistor or a P-type transistor. A structure consisting of only one of the transistors may also be used. There are no particular limitations on the crystallinity of the semiconductor films used in 502t and 2503t. In addition, amorphous semiconductor films and crystalline semiconductor films can be used as semiconductor materials. Group 13 semiconductors (e.g., semiconductors containing gallium), Group 14 semiconductors (e.g., silicon This method uses semiconductors containing ions, compound semiconductors (including oxide semiconductors), organic semiconductors, etc. This is possible. Either transistor 2502t or transistor 2503t or In both cases, the energy gap is 2 eV or more, preferably 2.5 eV or more, more preferably By using oxide semiconductors with a voltage of 3 eV or higher, the off-current of the transistor can be reduced. This is preferable because it allows for this. Examples of oxide semiconductors include In-Ga oxide and In-M-Zn acid Examples include monoxides (where M represents Al, Ga, Y, Zr, La, Ce, Sn, or Nd). It can be done.

[0295] <5-3. Explanation of Touch Sensors> Next, we will explain the details of the touch sensor 2595 using Figure 18(C). Figure 18 (C) corresponds to the cross-sectional view between the dashed line X3 and X4 shown in Figure 17(B).

[0296] The touch sensor 2595 has electrodes 2591 and electrodes arranged in a staggered pattern on the substrate 2590. 2592, an insulating layer 2593 covering electrodes 2591 and 2592, and adjacent electrodes 25 It has wiring 2594 that electrically connects 91.

[0297] Electrodes 2591 and 2592 are formed using a light-transmitting conductive material. Conductive materials having this property include indium oxide, indium tin oxide, and indium zinc oxide. Conductive oxides such as zinc oxide, zinc oxide, and zinc oxide with added gallium can be used. Furthermore, a film containing graphene can also be used. A film containing graphene is, for example, a film-like structure. A film containing graphene oxide formed on the surface can be reduced to form a new film. Methods such as applying heat can be cited.

[0298] For example, a light-transmitting conductive material is deposited on a substrate 2590 by sputtering. Afterwards, various patterning techniques such as photolithography are used to remove unwanted parts. Electrodes 2591 and 2592 can be formed.

[0299] Furthermore, the materials used for the insulating layer 2593 include, for example, resins such as acrylic and epoxy. In addition to resins containing siloxane bonds, silicon oxide, silicon oxide nitride, aluminum oxide Inorganic insulating materials such as MU can also be used.

[0300] Furthermore, an opening reaching the electrode 2591 is provided in the insulating layer 2593, and the wiring 2594 is adjacent to it. It is electrically connected to electrode 2591. The light-transmitting conductive material increases the aperture ratio of the touch panel. Because it can be done this way, it can be suitably used in wiring 2594. Also, electrode 2591 Furthermore, materials with higher conductivity than electrode 2592 are preferable for wiring 2594 because they can reduce electrical resistance. It can be used appropriately.

[0301] The electrode 2592 extends in one direction, and multiple electrodes 2592 are arranged in a stripe pattern. Furthermore, the wiring 2594 is provided intersecting with the electrode 2592.

[0302] A pair of electrodes 2591 are provided flanking one electrode 2592. Also, the wiring 2594 is A pair of electrodes 2591 are electrically connected.

[0303] Note that the multiple electrodes 2591 are not necessarily arranged in a direction perpendicular to that of a single electrode 2592. It is not necessary to do so; they may be positioned to form an angle greater than 0 degrees but less than 90 degrees.

[0304] Furthermore, wiring 2598 is electrically connected to electrode 2591 or electrode 2592. A portion of the wiring 2598 functions as a terminal. Wiring 2598 can be, for example, made of aluminum. Nium, gold, platinum, silver, nickel, titanium, tungsten, chromium, molybdenum, iron, corn Using metallic materials such as balsamic, copper, or palladium, or alloy materials containing such metallic materials. It is possible.

[0305] Furthermore, an insulating layer is provided to cover the insulating layer 2593 and the wiring 2594, and the touch sensor 2595 It may be protected.

[0306] Furthermore, the connecting layer 2599 electrically connects the wiring 2598 and the FPC2509(2). .

[0307] The connecting layer 2599 is an anisotropic conductive film (ACF: Anisotropic C (conductive film) or anisotropic conductive paste (ACP: Anisotropic) You can use tools such as IC Conductive Paste.

[0308] <5-4. Explanation regarding the touch panel 2> Next, we will explain the details of the touch panel 2000 using Figure 19(A). Figure 19 (A) corresponds to the cross-sectional view between the dashed line X5 and X6 shown in Figure 17(A).

[0309] The touch panel 2000 shown in Figure 19(A) is the same as the display panel 25 described in Figure 18(A). This configuration consists of 01 and the touch sensor 2595 described in Figure 18(C) bonded together.

[0310] Furthermore, the touch panel 2000 shown in Figure 19(A) is shown in Figures 18(A) and 18(C). In addition to the configuration described, it also includes an adhesive layer 2597 and an anti-reflective layer 2567p.

[0311] The adhesive layer 2597 is provided in contact with the wiring 2594. The circuit board 2590 is placed on the circuit board 2570 so that the sensor 2595 overlaps the display panel 2501. They are bonded together. Furthermore, it is preferable that the adhesive layer 2597 is translucent. For 2597, a thermosetting resin or an ultraviolet curing resin can be used. Using acrylic resin, urethane resin, epoxy resin, or siloxane resin. It is possible.

[0312] The anti-reflective layer 2567p is provided in a position that overlaps with the pixel. For example, a circular polarizer can be used.

[0313] Next, for a touch panel with a configuration different from that shown in Figure 19(A), see Figure 19(B). I will use it to explain.

[0314] Figure 19(B) is a cross-sectional view of the touch panel 2001. The touch panel shown in Figure 19(B) Nell 2001 is connected to the touch panel 2000 and the display panel 2501 shown in Figure 19(A). The position of the touch sensor 2595 is different. Here, we will explain the different configurations in detail. Where a similar configuration can be used, refer to the description of Touch Panel 2000.

[0315] The colored layer 2567R is located in a position that overlaps with the light-emitting element 2550. Also shown in Figure 19(B). The light-emitting element 2550 emits light towards the side where the transistor 2502t is located. As a result, some of the light emitted by the light-emitting element 2550 passes through the colored layer 2567R, and in the figure The light is emitted outwards from the light-emitting module 2580 in the direction of the indicated arrow.

[0316] Furthermore, the touch sensor 2595 is provided on the circuit board 2510 side of the display panel 2501. ru.

[0317] The adhesive layer 2597 is located between substrates 2510 and 2590, and is connected to the display panel 2501. Attach the touch sensor 2595.

[0318] As shown in Figures 19(A) and (B), the light emitted from the light-emitting element is directed towards the substrate 2510 and the base It is sufficient if the material is injected through either one or both of the plates 2570.

[0319] <5-5. Explanation of the touch panel operating method> Next, an example of a touch panel driving method will be explained using Figure 20.

[0320] Figure 20(A) is a block diagram showing the configuration of a mutually capacitive touch sensor. (A) shows the pulse voltage output circuit 2601 and the current detection circuit 2602. In Figure 20(A), the electrodes 2621 to which the pulse voltage is applied are denoted as X1-X6, and the current changes... The electrodes 2622 that detect the change are shown as Y1-Y6, each represented by six wires. Furthermore, Figure 20(A) shows the capacitance formed by the superposition of electrode 2621 and electrode 2622. This indicates 2603. Note that electrodes 2621 and 2622 have interchangeable functions. You may do so.

[0321] The pulse voltage output circuit 2601 is a circuit for sequentially applying pulses to the X1-X6 wiring. Therefore, when a pulse voltage is applied to the wiring X1-X6, the capacitance 2603 is formed. An electric field is generated between pole 2621 and electrode 2622. This electric field generated between electrodes is affected by shielding, etc. By causing a change in the mutual capacitance of the 2603 capacitance, the proximity of the detected object, or It can detect contact.

[0322] The current detection circuit 2602 detects changes in the mutual capacitance of capacitor 2603, and the wiring of Y1-Y6 This is a circuit for detecting changes in current. In the wiring of Y1-Y6, proximity of the object to be detected, Alternatively, if there is no contact, the detected current value will not change, but if the object being detected is nearby, When the mutual capacitance decreases due to contact, a change in the current value is detected. Output can be performed using an integrating circuit or similar.

[0323] Next, Figure 20(B) shows the input of the mutual capacitive touch sensor shown in Figure 20(A). The timing chart of the output waveform is shown. Figure 20(B) shows the timing of each matrix in one frame period. The system will detect the object to be detected. Also, in Figure 20(B), the case where no object to be detected is detected ( This shows two cases: one where the object to be detected is not touched, and another where the object to be detected is touched. Regarding the wiring of Y1-Y6, the waveforms shown represent the voltage values ​​corresponding to the detected current values. Yes, they are.

[0324] A pulse voltage is applied sequentially to the wiring of X1-X6, and Y1- The waveform changes in the Y6 wiring. If there is no proximity or contact with the detected object, X1-X6 The waveforms of Y1-Y6 change uniformly in response to changes in the voltage of the wiring. Meanwhile, when the object to be detected is nearby... Alternatively, at the point of contact, the current value decreases, and therefore the waveform of the corresponding voltage value also changes. ru.

[0325] In this way, by detecting changes in mutual capacitance, the proximity or contact of the object being detected can be detected. It is possible.

[0326] <5-6. Explanation of Sensor Circuits> Furthermore, in Figure 20(A), only a capacitor 2603 is provided at the wiring intersection as a touch sensor. The configuration of a passive touch sensor was shown, but an active touch sensor with transistors and capacitors is also shown. It may also be a type of touch sensor. One of the sensor circuits included in an active type touch sensor. An example is shown in Figure 21.

[0327] The sensor circuit shown in Figure 21 consists of capacitor 2603, transistor 2611, and transistor It has transistor 2612 and transistor 2613.

[0328] Transistor 2613 receives a signal G2 at its gate, and either its source or drain... A voltage VRES is applied, and the other side is one electrode of capacitor 2603 and transistor 2611 It is electrically connected to the gate. Transistor 2611 has either the source or the drain Electrically connect either the source or drain of transistor 2612, and apply a voltage VS to the other side. S is given. Transistor 2612 is given a signal G1 at its gate, and source or The other end of the drain is electrically connected to the wiring ML. The other electrode of the 2603 capacitance has a voltage VS. S is given.

[0329] Next, the operation of the sensor circuit shown in Figure 21 will be explained. First, as the signal G2, When a potential is applied that turns on transistor 2613, the gate of transistor 2611 A potential corresponding to the voltage VRES is applied to node n to which the signal G2 is connected. Next, the signal G2 and By applying a potential that turns off transistor 2613, the potential at node n becomes It is retained.

[0330] Next, the mutual capacitance of capacitance 2603 changes due to the proximity or contact of a detected object such as a finger. Consequently, the potential of node n changes from VRES.

[0331] The read operation applies a potential to signal G1 that turns on transistor 2612. The current flowing through transistor 2611, i.e., the current flowing through wiring ML, is determined by the potential of the current n. The current changes. By detecting this current, the proximity or contact of the object to be detected can be detected. It is possible.

[0332] As for transistors 2611, 2612, and 2613, It is preferable to use an oxide semiconductor layer as the semiconductor layer in which the channel region is formed. In particular, By applying such a transistor to the transistor 2613, the potential at node n can be changed. This makes it possible to retain the data for a long period of time, and the operation of resupplying VRES to node n ( This can reduce the frequency of fresh operations.

[0333] The configuration shown in this embodiment may be used in appropriate combination with the configurations shown in other embodiments. It is possible.

[0334] (Embodiment 6) In this embodiment, a display module and electronic device having a light-emitting device according to one aspect of the present invention are provided. This will be explained using Figures 22 and 23.

[0335] <6-1. Display Module> The display module 8000 shown in Figure 22 consists of an upper cover 8001 and a lower cover 8002. In between, touch sensor 8004 connected to FPC8003, and FPC8005 connected The display panel 8006, frame 8009, printed circuit board 8010, and battery 8011 To possess.

[0336] A light-emitting device according to one aspect of the present invention can be used, for example, in a display panel 8006.

[0337] The upper cover 8001 and the lower cover 8002 are the touch sensor 8004 and the display panel. The shape and dimensions can be appropriately modified to match the size of the 8006.

[0338] The touch sensor 8004 is a resistive or capacitive touch panel that can be used as a display panel. It can be used superimposed on 8006. Also, the opposing substrate (sealing substrate) of the display panel 8006 It is also possible to incorporate a touch sensor function into the board. It is also possible to provide an optical touch sensor by installing a light sensor in each pixel of 006.

[0339] Frame 8009 provides protection for the display panel 8006, as well as the movement of the printed circuit board 8010. It has the function of an electromagnetic shield to block electromagnetic waves generated by the operation. The 8009 may also function as a heat sink.

[0340] The printed circuit board 8010 contains power supply circuits and signals for outputting video and clock signals. It has a power processing circuit. The power supply that provides power to the power supply circuit is an external commercial power supply. Alternatively, a separate power source, the battery 8011, may also be used. This can be omitted when using commercial power.

[0341] Furthermore, the display module 8000 includes components such as polarizing plates, phase difference plates, and prism sheets. They may also be provided.

[0342] <6-2.Electronic equipment> Figures 23(A) to 23(G) show electronic devices. These electronic devices are enclosed in a housing. Body 9000, display unit 9001, speaker 9003, operation keys 9005, connection terminals 9006 It may have a sensor 9007, a microphone 9008, etc.

[0343] The electronic devices shown in Figures 23(A) to 23(G) can have a variety of functions. For example, a function that displays various information (still images, videos, text images, etc.) on the display unit, Chiss sensor function, calendar, date or time display function, various software ( The program controls processing, provides wireless communication, and uses wireless communication to perform various tasks. Features include the ability to connect to computer networks and transmit various types of data using wireless communication. Alternatively, it can perform receiving functions, or read programs or data recorded on a recording medium and display them. It can have a function to display on the display unit, etc. Note that Figures 23(A) to 23(G) The functions that the electronic devices shown may have are not limited to these, and may have a variety of functions. This is possible. Also, although not shown in Figures 23(A) to 23(G), electronic devices include: The configuration may have multiple display units. Furthermore, the electronic device may be equipped with a camera or the like to capture still images. Functions for taking photos, recording videos, and recording images on a storage medium (external or built into the camera). It may also have a function to save the image to the display unit, a function to display the captured image on the display unit, etc.

[0344] Details of the electronic equipment shown in Figures 23(A) to 23(G) will be explained below.

[0345] Figure 23(A) is a perspective view showing the personal digital assistant 9100. The display unit 9001 has flexibility. Therefore, it can be used on the curved surface of the curved housing 9000. The display unit 9001 can be incorporated accordingly. Furthermore, the display unit 9001 is a touch sensor. It features a stylus that allows you to operate it by touching the screen with your finger or a stylus. For example, the display By touching the icon displayed on the display unit 9001, you can launch the application. can.

[0346] Figure 23(B) is a perspective view showing the personal digital assistant 9101. The personal digital assistant 9101 is It has one or more functions selected from, for example, a telephone, a notebook, or an information viewing device. Physically, it can be used as a smartphone. Furthermore, the mobile information terminal 9101 is... The speaker 9003, connection terminal 9006, sensor 9007, etc. are omitted from the diagram, but It can be installed in the same position as the portable information terminal 9100 shown in 23(A). The information terminal 9101 can display text and image information on its multiple surfaces. For example, Three operation buttons 9050 (also called operation icons or simply icons) are on the display unit 900. It can be displayed on one side of 1. Also, the information 9051 shown by the dashed rectangle is displayed on the display unit 90 It can be displayed on other sides of 01. For example, information 9051 is an email. A display that notifies you of incoming calls from social networking services (SNS) or phone calls. Subject of email or social media post, sender's name, date and time, time, This includes battery level, antenna signal strength, etc. Alternatively, information 9051 may be displayed. Instead of displaying information 9051, you may also display an operation button 9050 or the like at that location.

[0347] Figure 23(C) is a perspective view showing the personal digital assistant 9102. The personal digital assistant 9102 is The display unit 9001 has the function of displaying information on three or more sides. Here, information 9052, This shows an example where information 9053 and information 9054 are displayed on different sides. For example, The user of the mobile information terminal 9102 stores the mobile information terminal 9102 in the breast pocket of their clothing. In this state, you can check the display (information 9053 in this case). Specifically, when an incoming call is received... The phone number or name of the caller can be observed from above the mobile information terminal 9102. The information is displayed on the device. The user can view the information without taking the portable information terminal 9102 out of their pocket. This allows you to check and decide whether or not to answer the call.

[0348] Figure 23(D) is a perspective view showing the wristwatch-type personal information terminal 9200. Personal information terminal The 9200 is a mobile phone, email, document viewing and creation, music playback, and internet communication. It can run various applications such as computer games. The display unit 9001 has a curved display surface, and displays are performed along the curved display surface. It can do this. Furthermore, the personal information terminal 9200 can perform standardized short-range wireless communication. This is possible. For example, by communicating with a wireless headset, It is also possible to make calls using the free-call function. In addition, the mobile information terminal 9200 has a connection terminal 9006. It has the capability to directly exchange data with other information terminals via a connector. Charging can also be performed via connection terminal 9006. Note that the charging operation is performed via connection terminal 900 This may also be done by wireless power transfer without using 6.

[0349] Figures 23(E),(F), and(G) are perspective views showing a foldable portable information terminal 9201. Furthermore, Figure 23(E) is a perspective view of the mobile information terminal 9201 in an unfolded state, and Figure 23 (F) changes the mobile information terminal 9201 from one state to the other, either unfolded or folded. This is a perspective view of the device in the process of being folded, with Figure 23(G) showing the portable information terminal 9201 in its folded state. This is a perspective view of the device. The 9201 portable information terminal offers excellent portability when folded, and when unfolded... In this configuration, the seamless, wide display area provides excellent readability. (Portable Information Terminal 92) The display unit 9001 of 01 is connected by three housings 9000 via a hinge 9055. It is supported by bending the two housings 9000 via the hinge 9055. Furthermore, the mobile information terminal 9201 can be reversibly transformed from an unfolded state to a folded state. This is possible. For example, the mobile information terminal 9201 can bend with a radius of curvature of 1 mm or more and 150 mm or less. It is possible to do so.

[0350] The electronic device described in this embodiment has a display unit for displaying some kind of information. The present invention is characterized by the following. However, one embodiment of the present invention is an electronic device that does not have a display unit. It can also be applied to the display unit of the electronic device described in this embodiment. In other words, a configuration that is flexible and can display along a curved display surface, or a folding While examples of foldable display unit configurations have been given, the system is not limited to these, and may also include non-flexible, planar displays. The display may also be configured to appear in the section.

[0351] The configuration shown in this embodiment may be used in appropriate combination with the configurations shown in other embodiments. It is possible.

[0352] (Embodiment 7) In this embodiment, a light-emitting device according to one aspect of the present invention will be described with reference to Figure 24.

[0353] <7. Light-emitting device> A perspective view of the light-emitting device 3000 shown in this embodiment is shown in Figure 24(A). Figure 24(B) shows the cross-sectional views corresponding to the section between the dashed lines E and F. In A), some of the components are shown with dashed lines to avoid complexity in the drawing.

[0354] The light-emitting device 3000 shown in Figures 24(A) and (B) consists of a substrate 3001 and a light-emitting device on the substrate 3001. The optical element 3005, the first sealing region 3007 provided on the outer periphery of the light-emitting element 3005, and It has a second sealing region 3009 provided on the outer periphery of the first sealing region 3007.

[0355] Furthermore, the light emitted from the light-emitting element 3005 is emitted from either substrate 3001 or substrate 3003. Or they are emitted from both. In Figures 24(A)(B), the emission from the light-emitting element 3005 This section describes a configuration in which light is emitted downwards (towards the substrate 3001).

[0356] Furthermore, as shown in Figures 24(A) and (B), the light-emitting device 3000 has a light-emitting element 3005. A double sealing structure is arranged surrounded by a first sealing region 3007 and a second sealing region 3007. It is constructed in a double-sealed structure that prevents external impurities from entering the light-emitting element 3005 side (e.g., For example, water, oxygen, etc. can be suitably suppressed. However, the first sealing region 300 7 and the second sealing region 3009 do not necessarily need to be provided. For example, the first sealing region 3 It may also consist solely of 007.

[0357] In Figure 24(B), the first sealing region 3007 and the second sealing region 3009 are , provided in contact with substrates 3001 and 3003. However, it is not limited to this, for example If, then, one or both of the first sealing region 3007 and the second sealing region 3009 are located on the substrate 30 The configuration may also involve providing the insulating film or conductive film formed above 01 in contact with it. Alternatively, one or both of the first sealing region 3007 and the second sealing region 3009 are substrate The 3003 may be configured to be in contact with an insulating film or conductive film formed below it. stomach.

[0358] Substrates 3001 and 3003 are the same as substrate 10 described in Embodiment 1 above. 2. The same configuration as substrate 152 can be used. The light-emitting element 3005 can be the same as in the previous implementation. The configuration may be the same as any one of the first to third light-emitting elements described in the description. .

[0359] The first sealing region 3007 is a material containing glass (e.g., glass frit, glass). A ribbon or similar material can be used. Furthermore, the second sealing region 3009 may be a resin-containing material. This can be used. By using a material containing glass as the first sealing region 3007, Productivity and sealing properties can be improved. In addition, the second sealing region 3009 contains resin. By using this material, impact resistance and heat resistance can be improved. However, the first sealing area 3007 and the second sealing region 3009 are, but are not limited to, the first sealing region 3007 The first part is formed from a resin-containing material, and the second sealing region 3009 is formed from a glass-containing material. That's good too.

[0360] Furthermore, the above-mentioned glass frits include, for example, magnesium oxide, calcium oxide, Strontium oxide, barium oxide, cesium oxide, sodium oxide, potassium oxide, acid Boron oxide, vanadium oxide, zinc oxide, tellurium oxide, aluminum oxide, silicon dioxide Lead oxide, tin oxide, phosphorus oxide, ruthenium oxide, rhodium oxide, iron oxide, copper oxide, diacitates Manganese oxide, molybdenum oxide, niobium oxide, titanium oxide, tungsten oxide, bismoxide Zirconium oxide, lithium oxide, antimony oxide, lead borate glass, tin phosphate Includes glass, vanadate glass, or borosilicate glass, etc. A small amount is used to absorb infrared light. Preferably, the product contains at least one transition metal.

[0361] Furthermore, as for the glass frit mentioned above, for example, by applying frit paste onto a substrate, This is then subjected to heat treatment or laser irradiation. The frit paste contains the above glass frit It contains a stencil and a resin (also called a binder) diluted with an organic solvent. A net containing an absorbent that absorbs light of the wavelength of laser light may also be used. For example, it is preferable to use an Nd:YAG laser or a semiconductor laser. Furthermore, the shape of the laser beam during laser irradiation can be either circular or square.

[0362] Furthermore, examples of materials containing the above-mentioned resins include polyester, polyolefin, and poly Amides (nylon, aramid, etc.), polyimides, polycarbonates, polyurethanes, acrylics Use a material containing yl resin, epoxy resin, or a resin having siloxane bonds. It is possible.

[0363] Furthermore, either one or both of the first sealing region 3007 and the second sealing region 3009 may be used. When using a material containing glass, the thermal expansion coefficient between the glass-containing material and the substrate 3001 It is preferable that they are close together. With the above configuration, the material containing glass or base will be affected by thermal stress. This can prevent cracks from forming in plate 3001.

[0364] For example, a material containing glass is used in the first sealing region 3007, and the second sealing region 3009 When using a material containing resin, the following excellent effects are obtained.

[0365] The second sealing region 3009 extends further outward than the first sealing region 3007 of the light-emitting device 3000. It is located on the side closer to the part. The light-emitting device 3000 is distorted by external forces, etc., as it moves towards the outer circumference. The distortion increases. Therefore, the outer periphery side of the light-emitting device 3000, i.e., the second side, becomes more distorted. The sealing region 3009 is sealed with a resin-containing material, and the second sealing region 3009 is By sealing the first sealing region 3007 provided on the inside with a material including glass, The light-emitting device 3000 becomes less prone to damage even when subjected to external forces or other distortions.

[0366] Furthermore, as shown in Figure 24(B), substrate 3001, substrate 3003, first sealing region 30 The region enclosed by 07 and the second sealing region 3009 becomes the first region 3011. Furthermore, the substrate 3001, substrate 3003, light-emitting element 3005, and the first sealing region 3007 are surrounded The region that was created becomes the second region, 3013.

[0367] The first region 3011 and the second region 3013 are, for example, noble gases or nitrogen gases. It is preferable that the area is filled with an inert gas such as the first region 3011 and the second region For 3013, a reduced pressure state is preferable to an atmospheric pressure state.

[0368] Furthermore, a modified example of the configuration shown in Figure 24(B) is shown in Figure 24(C). Figure 24(C) shows the light emission. This is a cross-sectional view showing a modified example of the apparatus 3000.

[0369] Figure 24(C) shows a recess provided in a part of the substrate 3003, with a desiccant 3018 placed in the recess. This is the configuration. The rest of the configuration is the same as that shown in Figure 24(B).

[0370] Desiccant 3018 is a substance that adsorbs moisture, etc., by chemical adsorption, or by physical adsorption. Therefore, a substance that adsorbs moisture, etc., can be used. For example, it can be used as a desiccant 3018. Substances that can be converted include alkali metal oxides and alkaline earth metal oxides (oxidation). Calcium, barium oxide, etc.), sulfates, metal halides, perchlorates, zeolites, Examples include silica gel.

[0371] Next, regarding a modified example of the light-emitting device 3000 shown in Figure 24(B), see Figures 25(A)(B)( We will explain using C)(D). Note that Figures 25(A)(B)(C)(D) are the same as Figure 24(B). This is a cross-sectional view illustrating a modified example of the light-emitting device 3000 shown.

[0372] The light-emitting device shown in Figure 25(A) does not have a second sealing region 3009, but rather a first sealing region The configuration is 3007. Also, the light-emitting device shown in Figure 25(A) is shown in Figure 24(B). It has region 3014 instead of the second region 3013.

[0373] Examples of materials in area 3014 include polyester, polyolefin, and polyamide (nylon Polyimide, polycarbonate or acrylic resin, polyurethane, (e.g., aramid), polyimide, polycarbonate or acrylic resin, polyurethane Materials containing epoxy resin or resins having siloxane bonds can be used.

[0374] Region 3014, by using the materials described above, is made into a so-called solid-encapsulated light-emitting device. It is possible.

[0375] Furthermore, the light-emitting device shown in Figure 25(B) is on the substrate 3001 side of the light-emitting device shown in Figure 25(A). The configuration involves providing a substrate 3015.

[0376] The substrate 3015 has irregularities as shown in Figure 25(B). By providing this on the side from which the light-emitting element 3005 is extracted, the light-emitting element 3005 This can improve the efficiency of light extraction. Furthermore, the uneven surface shown in Figure 25(B) Instead of having a structure, a substrate that functions as a diffuser may be provided.

[0377] Furthermore, the light-emitting device shown in Figure 25(C) is located on the substrate 3001 side of the light-emitting device shown in Figure 25(A). While the previous structure extracted light from one side, this structure extracts light from the substrate 3003 side.

[0378] The light-emitting device shown in Figure 25(C) has substrate 3015 on the substrate 3003 side. The configuration is the same as that of the light-emitting device shown in Figure 25(B).

[0379] Furthermore, the light-emitting device shown in Figure 25(D) is the substrate 3003 of the light-emitting device shown in Figure 25(C), This configuration involves providing substrate 3016 without providing 3015.

[0380] The substrate 3016 has a first uneven surface located near the light-emitting element 3005, and the light-emitting element 300 It has a second uneven surface located on the far side of 5. By using the configuration shown in Figure 25(D), The efficiency of light extraction from the light-emitting element 3005 can be further improved.

[0381] Therefore, by implementing the configuration shown in this embodiment, impurities such as water and oxygen can be eliminated. This makes it possible to realize a light-emitting device in which the degradation of the light-emitting element is suppressed. Alternatively, this implementation By implementing the configuration shown in the image, it is possible to realize a light-emitting device with high light extraction efficiency. Cut.

[0382] The configuration shown in this embodiment may be combined with the configurations shown in other embodiments or examples as appropriate. They can be combined.

[0383] (Embodiment 8) In this embodiment, a light-emitting device according to one aspect of the present invention is applied to various lighting devices and electronic devices. An example of this will be explained using Figure 26.

[0384] <8. Lighting equipment and electronic devices> A light-emitting device according to one aspect of the present invention is fabricated on a flexible substrate, thereby having a curved surface This enables the realization of electronic devices and lighting devices that have a light-emitting region.

[0385] Furthermore, a light-emitting device to which one aspect of the present invention is applied can also be applied to the lighting of automobiles. For example, lighting can be installed on the dashboard, windshield, ceiling, etc.

[0386] Figure 26(A) shows a perspective view of one side of the multi-function terminal 3500, and Figure 26(B) shows a multi This shows a perspective view of the other side of the functional terminal 3500. The multifunctional terminal 3500 is housed in a casing 350. The display unit 3504, camera 3506, lighting 3508, etc. are incorporated into 2. The light-emitting device of the form can be used for illumination 3508.

[0387] The illumination 3508 functions as a surface light source by using a light-emitting device according to one aspect of the present invention. Therefore, unlike point light sources such as LEDs, it is possible to obtain light emission with less directionality. When using the lighting 3508 and camera 3506 in combination, the lighting 3508 is turned on. Alternatively, it can be made to blink and imaged by camera 3506. The illumination 3508 is as follows: Because it functions as a surface light source, it can take photos that look like they were taken under natural light. Cut.

[0388] Note that the multi-function terminal 3500 shown in Figures 26(A) and (B) is the same as shown in Figures 23(A) to 23( Similar to the electronic devices shown in G), they can have a variety of functions.

[0389] Furthermore, inside the housing 3502 are a speaker and sensors (force, displacement, position, velocity, acceleration, angle). Speed, rotation speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, electric current, Includes functions for measuring voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared radiation. It can have a microphone, etc. Also, inside the multifunction terminal 3500, By providing a detection device that has sensors for detecting tilt, such as gyroscopes and accelerometers, The orientation (portrait or landscape) of the functional terminal 3500 is determined, and the screen display of the display unit 3504 is automatically adjusted. It can be made to switch between modes.

[0390] The display unit 3504 can also function as an image sensor. For example, the display unit 3 By touching the 504 with their palm or fingers, the user can be authenticated by capturing images of their palm print, fingerprints, etc. Furthermore, the display unit 3504 is equipped with a backlight that emits near-infrared light or a sensor that emits near-infrared light. By using a light source for imaging, it is also possible to image finger veins, palmar veins, etc. Note that the display unit 35 A light-emitting device according to one aspect of the present invention may be applied to 04.

[0391] Figure 26(C) shows a perspective view of the security light 3600. The light 3600 is, The housing 3602 has lighting 3608 on its exterior, and the housing 3602 incorporates a speaker 3610, etc. It is incorporated. A light-emitting device according to one aspect of the present invention can be used for illumination 3608.

[0392] Light 3600, for example, grips, grasps, or holds Light 3608. It can emit light by doing so. Also, inside the housing 3602, from light 3600 The device may also include an electronic circuit capable of controlling the method of light emission. For example, the electronic circuit may be one Alternatively, the circuit may be designed to emit light intermittently multiple times, or the current value of the light emission may be controlled. This may result in a circuit that allows the amount of light emitted to be adjusted. Also, the light emitted from the lighting 3608 and At the same time, you could incorporate a circuit that outputs a loud alarm sound from speaker 3610. stomach.

[0393] As for the Light 3600, it can emit light in any direction, so for example, against an assailant It can be used to intimidate animals with light, or light and sound. Additionally, the Light 3600 has digital capabilities. It may also be equipped with a camera or other camera-related functions that allow for shooting.

[0394] As described above, a lighting device and an electronic device are obtained by applying a light-emitting device according to one aspect of the present invention. This is possible. The applicable lighting devices and electronic equipment are those shown in this embodiment. It is applicable to lighting devices and electronic equipment in all fields, not just limited to those areas.

[0395] The configuration shown in this embodiment may be used in appropriate combination with the configurations shown in other embodiments. It is possible to be there. [Explanation of Symbols]

[0396] 100 light-emitting elements 102 circuit boards 104 Electrode 108 EL layer 110 Emitting layer 112 Emitting layer 114 Electrode 116 Emitting layer 121 Host Materials 121_1 Organic compounds 121_2 Organic compounds 122 Guest Materials 131 Hole injection layer 132 Hole transport layer 133 Electron transport layer 134 Electron injection layer 140 buffer layers 141 EL layer 142 EL layer 143 Charge generation layer 150 light-emitting elements 150A Light-emitting element 152 circuit boards 221 Host Materials 221_1 Organic compounds 221_2 Organic compounds 222 Guest Materials 301_1 Wiring 301_5 Wiring 301_6 Wiring 301_7 Wiring 302_1 Wiring 302_2 Wiring 303_1 Transistor 303_6 Transistor 303_7 Transistor 304 Capacitive element 304_1 Capacitive element 304_2 Capacitive element 305 Light-emitting element 306_1 Wiring 306_3 Wiring 307_1 Wiring 307_3 Wiring 308_1 Transistor 308_6 Transistor 309_1 Transistor 309_2 Transistor 311_1 Wiring 311_3 Wiring 312_1 Wiring 312_2 Wiring 415 Hole injection layer 416 Hole transport layer 417 Electron transport layer 418 Electron injection layer 431 Host Materials 431_1 Organic compounds 431_2 Organic compounds 432 Guest Materials 441 Host materials 441_1 Organic compounds 441_2 Organic compounds 442 Guest Materials 444 Emitting layer 445 Emitting layer 801 Pixel Circuit 802 pixel section 804 Drive Circuit Section 804a Gate Driver 804b Source Driver 806 protection circuit 807 Terminal section 852 transistors 854 transistors 862 Capacitive elements 872 Light-emitting element 2000 Touch Panel 2001 Touch Panel 2501 Display Panel 2502 pixels 2502t Transistor 2503c Capacitive element 2503g Scan line drive circuit 2503t Transistor 2509 FPC 2510 circuit board 2510a Insulating layer 2510b flexible substrate 2510c adhesive layer 2511 Wiring 2519 terminal 2521 Insulating layer 2528 Bulkhead 2550 Light-emitting element 2560 Sealing layer 2567BM light shielding layer 2567p anti-reflection layer 2567R colored layer 2570 circuit board 2570a Insulating layer 2570b flexible substrate 2570c adhesive layer 2580 Light-Emitting Module 2590 circuit board 2591 Electrode 2592 Electrode 2593 Insulating layer 2594 Wiring 2595 Touch Sensor 2597 Adhesive layer 2598 Wiring 2599 Connectivity Layer 2601 Pulse voltage output circuit 2602 Current detection circuit 2603 Capacity 2611 Transistors 2612 transistors 2613 Transistors 2621 Electrode 2622 Electrode 3000 Light-emitting devices 3001 circuit board 3003 circuit board 3005 Light-emitting element 3007 Sealing area 3009 Sealing area 3011 area 3013 area 3014 area 3015 circuit board 3016 circuit board 3018 Desiccant 3500 Multifunctional Terminals 3502 enclosure 3504 Display section 3506 Camera 3508 Lighting 3600 Lights 3602 enclosure 3608 Lighting 3610 speaker 8000 Display Module 8001 Top cover 8002 Lower cover 8003 FPC 8004 Touch Sensor 8005 FPC 8006 Display Panel 8009 Frame 8010 Printed Circuit Board 8011 Battery 9000 cabinets 9001 Display section 9003 Speaker 9005 Operation Keys 9006 Connection terminal 9007 Sensor 9008 Microphone 9050 Operation Buttons 9051 Information 9052 Information 9053 Information 9054 Information 9055 Hinge 9100 Mobile Information Terminal 9101 Mobile Information Terminal 9102 Mobile Information Terminal 9200 Mobile Information Terminal 9201 Mobile Information Terminal

Claims

[Claim 1] A light-emitting element having a light-emitting layer between a pair of electrodes, The light-emitting element comprises a first light-emitting layer and a second light-emitting layer. The first light-emitting layer has a fluorescent material, The second light-emitting layer has a phosphorescent material, A light-emitting element in which the difference in peak values ​​between a first emission spectrum emitted from the first light-emitting layer and a second emission spectrum emitted from the second light-emitting layer is within 30 nm.

Images