Abstract: A light-emitting apparatus including a first light-emitting device and a second light-emitting device is provided. The first light-emitting device includes a first electrode, a second electrode, a first light-emitting layer positioned between the first electrode and the second electrode, a first layer positioned between the first electrode and the first light-emitting layer, and a second layer positioned between the first layer and the first light-emitting layer. The second light-emitting device includes a third electrode, a fourth electrode, a second light-emitting layer positioned between the third electrode and the fourth electrode, a third layer positioned between the third electrode and the second light-emitting layer, a fourth layer positioned between the third layer and the second light-emitting layer, and a fifth layer positioned between the third electrode and the second light-emitting layer. The first light-emitting layer includes a first light-emitting substance.

Abstract: A light-emitting apparatus with high emission efficiency is provided. A light-emitting apparatus including a light-emitting device A and a light-emitting device B is provided. The light-emitting device A includes a first electrode A, a second electrode A, a light-emitting layer A between the first electrode A and the second electrode A, and a first layer A between the first electrode A and the light-emitting layer A. The light-emitting device B includes a first electrode B, a second electrode B, a light-emitting layer B between the first electrode B and the second electrode B, a first layer B between the first electrode B and the light-emitting layer B, and a second layer B between the first electrode B and the light-emitting layer B. The light-emitting layer A contains a light-emitting substance A. The light-emitting layer B contains a light-emitting substance B. An emission peak wavelength of the light-emitting substance A is shorter than an emission peak wavelength of the light-emitting substance B.

Abstract: A light-emitting apparatus including a light-emitting device A and a light-emitting device B is provided. The light-emitting device A includes a first electrode A, a second electrode A, a light-emitting layer A interposed between the first electrode A and the second electrode A, a first layer A interposed between the first electrode A and the light-emitting layer A, and a second layer A interposed between the first layer A and the light-emitting layer A. The light-emitting device B includes a first electrode B, a second electrode B, a light-emitting layer B interposed between the first electrode B and the second electrode B, a first layer B interposed between the first electrode B and the light-emitting layer B, a second layer B positioned between the first layer B and the light-emitting layer B, and a third layer B interposed between the first electrode B and the light-emitting layer B. The light-emitting layer A contains a light-emitting substance A.

Abstract: A light-emitting apparatus with high emission efficiency is provided. The light-emitting apparatus includes light-emitting devices A and B each including an anode, a cathode, and an EL layer. An EL layer A includes a first layer A to a third layer A and a light-emitting layer A. An EL layer B includes a first layer B to a fourth layer B and a light-emitting layer B. The light-emitting layer A includes a light-emitting substance A and the light-emitting layer B includes a light-emitting substance B. An emission peak wavelength (wavelength A) of the light-emitting substance A is shorter than an emission peak wavelength (wavelength B) of the light-emitting substance B. The first layers A and B have similar structures, the second layers A and B have similar structures, and the third layers A and B have similar structures. The ordinary refractive index (no) of each of the first layer A and the third layer A is lower than the no of the second layer A at the wavelength A.

Abstract: A display apparatus having a function of emitting visible light and infrared light and a light detection function is provided. The display apparatus includes a first light-emitting device, a second light-emitting device, and a light-receiving device in a display portion. The first light-emitting device emits both visible light and infrared light and the second light-emitting device emits visible light. The light-receiving device has a function of absorbing at least part of visible light and infrared light. The first light-emitting device includes a first pixel electrode, a first light-emitting layer, a second light-emitting layer, and a common electrode. The second light-emitting device includes a second pixel electrode, a third light-emitting layer, and the common electrode. The light-receiving device includes a third pixel electrode, an active layer, and the common electrode. The first light-emitting layer includes a light-emitting material emitting infrared light.

Abstract: A light-emitting element with high emission efficiency. The light-emitting element includes a first organic compound, a second organic compound, and a guest material. The LUMO level of the first organic compound is lower than the LUMO level of the second organic compound. The HOMO level of the first organic compound is lower than the HOMO level of the second organic compound. The HOMO level of the guest material is higher than the HOMO level of the second organic compound. The energy difference between the LUMO level of the guest material and the HOMO level of the guest material is larger than the energy difference between the LUMO level of the first organic compound and the HOMO level of the second organic compound. The guest material has a function of converting triplet excitation energy into light emission. The first organic compound and the second organic compound form an exciplex.

Abstract: To provide a novel arylamine compound with a low refractive index. The provided arylamine compound includes at least one aromatic group. The aromatic group includes a first benzene ring, a second benzene ring, a third benzene ring, and at least three alkyl groups. The first benzene ring, the second benzene ring, and the third benzene ring are directly bonded in this order. The first benzene ring is bonded to nitrogen of amine. The first benzene ring may further include a substituted or unsubstituted phenyl group. The second benzene ring or the third benzene ring may further include an alkylated phenyl group. Each of first positions and third positions of two or more of the first to third benzene rings is independently bonded to another benzene ring, a benzene ring of the alkylated phenyl group, any of the at least three alkyl groups, or the nitrogen of the amine.

Abstract: A novel light-emitting device that is highly convenient, useful, or reliable is provided. The light-emitting device includes a first electrode, a second electrode, a first layer, a second layer, and a third layer. The first layer is interposed between the first electrode and the second electrode. The second layer is interposed between the second electrode and the first layer. The third layer is interposed between the second layer and the first layer. The first layer contains a first light-emitting material. The first light-emitting material has an emission spectrum having a peak at a wavelength ?1. The first layer has an ordinary refractive index n1 at the wavelength ?1. The second layer contains a second light-emitting material. The second light-emitting material has an emission spectrum having a peak at a wavelength ?2. The second layer has an ordinary refractive index n2 at the wavelength ?2.

Abstract: An electronic device with high outcoupling efficiency or a high light-trapping effect is provided. The electronic device includes a first layer and a second layer between a first electrode and a second electrode, the first layer is included between the first electrode and the second layer, the first layer includes a first organic compound and a first substance, the refractive index of a thin film of the first organic compound is higher than or equal to 1 and lower than or equal to 1.75, the first substance has an electron-accepting property, and the second layer has a function of emitting or absorbing light.

Abstract: Provided is a light-emitting element which has an anode, a light-emitting layer over the anode, an electron-transport layer over and in contact with the light-emitting layer, an electron-injection layer over and in contact with the electron-transport layer, and a cathode over and in contact with the electron-injection layer. The light-emitting layer has an electron-transport property, and the electron-transport layer includes an anthracene derivative. The light-emitting layer further includes a phosphorescent substance. This device structure allows the formation of a highly efficient blue-emissive light-emitting element even though the phosphorescent substance has higher triplet energy than the anthracene derivative which directly contacts with the light-emitting layer.

Abstract: A tandem light-emitting device that can be suitably used for a high-resolution display device is provided. The light-emitting device includes a first electrode, a second electrode facing the first electrode, a first light-emitting layer, a second light-emitting layer, and a first layer. The first light-emitting layer and the second light-emitting layer are between the first electrode and the second electrode. The first layer is between the first light-emitting layer and the second light-emitting layer. GSP_slope (mV/nm) of the first layer and GSP_slope (mV/nm) of the first light-emitting layer are denoted by signs of opposite polarities. Note that the GSP_slope (mV/nm) is a parameter represented by V/d when a surface potential and a thickness of a film are represented by V (mV) and d (nm), respectively.

Abstract: A display device that has a function of emitting visible light and infrared light and a function of detecting light. The display device is a display device including a first light-emitting device, a second light-emitting device, and a light-receiving device, in a display portion. The first light-emitting device includes a first pixel electrode, a first optical adjustment layer, a first light-emitting layer, a second light-emitting layer, and a common electrode. The second light-emitting device includes a second pixel electrode, a second optical adjustment layer, the first light-emitting layer, the second light-emitting layer, and the common electrode. The light-receiving device includes a third pixel electrode, an active layer, and the common electrode. The active layer includes an organic compound. The first light-emitting device emits infrared light emitted by the first light-emitting layer. The second light-emitting device emits visible light emitted by the second light-emitting layer.

Abstract: A light-emitting device with high emission efficiency is provided. The light-emitting device includes a first electrode, a second electrode, and an EL layer positioned between the first electrode and the second electrode. The EL layer includes at least a light-emitting layer, a first layer, a second layer, and a third layer. The first layer is positioned between the first electrode and the light-emitting layer. The third layer is positioned between the first layer and the light-emitting layer. The second layer is positioned between the first layer and the third layer. The first layer includes a first organic compound. The second layer includes a second organic compound. The third layer includes a third organic compound. The ordinary refractive index of the second organic compound is higher than the ordinary refractive index of the first organic and the ordinary refractive index of the third organic compound.

Abstract: A light-emitting device with high outcoupling efficiency is provided. In the light-emitting device including a light-emitting layer between a pair of electrodes, a low refractive index layer containing an organic compound and an inorganic compound is provided between the light-emitting layer and an anode or between the light-emitting layer and a cathode, and the low refractive index layer has a refractive index of less than or equal to 1.80 at a wavelength of light extracted from the light-emitting layer.

Abstract: A light-emitting element having low driving voltage and high emission efficiency is provided. In the light-emitting element, a combination of a guest material and a host material forms an exciplex. The guest material is capable of converting triplet excitation energy into light emission. Light emission from the light-emitting layer includes light emission from the guest material and light emission from the exciplex. The percentage of the light emission from the exciplex to the light emission from the light-emitting layer is greater than 0 percent and less than or equal to 60 percent. The energy after subtracting the energy of light emission from the exciplex from the energy of light emission from the guest material is greater than 0 eV and less than or equal to 0.23 eV.

Abstract: A novel organic compound is provided. A novel organic compound having a carrier-transport property is provided. A novel organic compound having a hole-transport property is provided. An organic compound having a low refractive index is provided. An organic compound having a low refractive index and a carrier-transport property is provided. An organic compound having a low refractive index and a hole-transport property is provided. An organic compound represented by the following general formula (G1) is provided.

Abstract: A light-emitting element with high emission efficiency. The light-emitting element includes a first organic compound, a second organic compound, and a guest material. The LUMO level of the first organic compound is lower than the LUMO level of the second organic compound. The HOMO level of the first organic compound is lower than the HOMO level of the second organic compound. The HOMO level of the guest material is higher than the HOMO level of the second organic compound. The energy difference between the LUMO level of the guest material and the HOMO level of the guest material is larger than the energy difference between the LUMO level of the first organic compound and the HOMO level of the second organic compound. The guest material has a function of converting triplet excitation energy into light emission. The first organic compound and the second organic compound form an exciplex.

Abstract: An organic compound with an electron-injection property and low water solubility is provided. An organic compound represented by General Formula (G1) is provided. In General Formula (G1), Ar is an aromatic skeleton represented by General Formula (Ar-1); L represents an alkylene group or an arylene group; n represents an integer of 0 to 3; m represents an integer of 1 to 4; and each of R1 to R12 independently represents hydrogen or an alkyl group. In General Formula (Ar-1), each of rings A, B, C, and D independently represents a benzene ring, a naphthalene ring, or a phenanthrene ring; any m carbon atoms on the rings A, B, C, and D each include a bond in General Formula (G1); X1 represents C, Si, or Ge; and ai represents a single bond, O, S, C including a substituent, Si including a substituent, or Ge including a substituent.

Abstract: A display apparatus having a function of emitting visible light and infrared light and a light detection function is provided. The display apparatus includes a first light-emitting device, a second light-emitting device, and a light-receiving device in a display portion. The first light-emitting device emits both visible light and infrared light and the second light-emitting device emits visible light. The light-receiving device has a function of absorbing at least part of visible light and infrared light. The first light-emitting device includes a first pixel electrode, a first light-emitting layer, a second light-emitting layer, and a common electrode. The second light-emitting device includes a second pixel electrode, a third light-emitting layer, and the common electrode. The light-receiving device includes a third pixel electrode, an active layer, and the common electrode. The first light-emitting layer includes a light-emitting material emitting infrared light.

Abstract: A novel light-emitting device that is highly convenient, useful, or reliable is provided. The light-emitting device includes a first electrode, a second electrode, a first unit, and a first layer. The first unit is positioned between the first electrode and the second electrode and contains a first light-emitting material. The first layer is positioned between the second electrode and the first unit and contains a first organic compound and a second organic compound. The first organic compound has an acid dissociation constant pKa larger than or equal to 8, and the second organic compound has no pyridine ring, no phenanthroline ring, or one phenanthroline ring.