Abstract: A light-emitting element includes a cathode, an anode, a light-emitting layer, a first layer, a second layer, and a third layer. The first layer is provided between the cathode and the light-emitting layer. The second layer is provided between the light-emitting layer and the third layer and includes a region in contact with the third layer. The third layer is provided between the second layer and the anode and includes a region in contact with the anode. The first layer and the third layer each include an alkali metal or an alkaline earth metal. The second layer includes a material that has a function of transporting an electron.

Abstract: A light-emitting panel including at least a first light-emitting element, each light-emitting element having, between a first conductive film and a second conductive film, a first layer including a metal and a second layer including a light-emitting organic compound. The second layer having the organic compound emits light having a wavelength between 600 nm and 800 nm, and light having a wavelength between 400 nm and 600 nm. The distance between the first conductive film and the second conductive film in one of the light emitting elements being N/2 (where N is a natural number) of a length between 600 nm and 800 nm, and the distance between the first conductive film and the second conductive film in the other one of the light-emitting elements being N/2 (where N is a natural number) of a length between 400 nm and 600 nm.

Abstract: A display panel includes a plurality of light-emitting elements. Light emitted from a first light-emitting element has a CIE 1931 chromaticity coordinate x of greater than 0.680 and less than or equal to 0.720 and a CIE 1931 chromaticity coordinate y of greater than or equal to 0.260 and less than or equal to 0.320. Light emitted from a second light-emitting element has a CIE 1931 chromaticity coordinate x of greater than or equal to 0.130 and less than or equal to 0.250 and a CIE 1931 chromaticity coordinate y of greater than 0.710 and less than or equal to 0.810. Light emitted from a third light-emitting element has a CIE 1931 chromaticity coordinate x of greater than or equal to 0.120 and less than or equal to 0.170 and a CIE 1931 chromaticity coordinate y of greater than or equal to 0.020 and less than 0.060.

Abstract: Emission efficiency of a light-emitting element is improved. The light-emitting element has a pair of electrodes and an EL layer between the pair of electrodes. The EL layer includes a first light-emitting layer and a second light-emitting layer. The first light-emitting layer includes a fluorescent material and a host material. The second light-emitting layer includes a phosphorescent material, a first organic compound, and a second organic compound. An emission spectrum of the second light-emitting layer has a peak in a yellow wavelength region. The first organic compound and the second organic compound form an exciplex.

Abstract: To provide a novel light-emitting element or a novel light-emitting device with high emission efficiency and low power consumption, a light-emitting element having a plurality of light-emitting layers between a pair of electrodes includes a lower electrode, a first light-emitting layer over the lower electrode, a charge-generation layer over the first light-emitting layer, a second light-emitting layer over the charge-generation layer, and an upper electrode over the second light-emitting layer. An emission spectrum of the first light-emitting layer peaks at a longer wavelength than an emission spectrum of the second light-emitting layer. A distance of between a bottom surface of the upper electrode and a bottom surface of the first light-emitting layer is less than or equal to 130 nm.

Abstract: Provided is a light-emitting device that can display an image with a wide color gamut or a novel light-emitting element. The light-emitting device includes a plurality of light-emitting elements each of which includes an EL layer between a pair of electrodes. Light obtained from a first light-emitting element through a first color filter has, on chromaticity coordinates (x, y), a chromaticity x of greater than 0.680 and less than or equal to 0.720 and a chromaticity y of greater than or equal to 0.260 and less than or equal to 0.320. Light obtained from a second light-emitting element through a second color filter has, on chromaticity coordinates (x, y), a chromaticity x of greater than or equal to 0.130 and less than or equal to 0.250 and a chromaticity y of greater than 0.710 and less than or equal to 0.810. Light obtained from a third light-emitting element through a third color filter has, on chromaticity coordinates (x, y), a chromaticity x of greater than or equal to 0.120 and less than or equal to 0.

Abstract: A furopyrazine derivative that is a novel organic compound is provided. The organic compound has a furopyrazine skeleton and is represented by General Formula (G1). In General Formula (G1), Q represents oxygen or sulfur, Ar1 represents a substituted or unsubstituted condensed aromatic ring, R1 and R2 independently represent hydrogen or a group having 1 to 100 total carbon atoms, and at least one of R1 and R2 has a hole-transport skeleton.

Abstract: A novel light-emitting element is provided. A light-emitting element that emits red light with high color purity and has high emission efficiency is provided. A full-color light-emitting device having low power consumption is provided. In the light-emitting element that exhibits white light emission, the emission wavelength range of red light is a specific range on the longer wavelength side than the conventional emission wavelength range of red light that is usually used, and an optical element having a specific transmittance in the specific wavelength range is used.

Abstract: To provide a display device with low power consumption. The display device includes a plurality of pixels each having a light-emitting element having a structure in which light emitted from a light-emitting layer is resonated between a reflective electrode and a light-transmitting electrode, wherein no color filter layers are provided or color filter layers with high transmittance are provided in pixels for light with relatively short wavelengths (e.g., pixels for blue and/or green), and a color filter layer is selectively provided in pixels for light with a long wavelength (e.g., pixels for red), and thereby maintaining color reproducibility and consuming less power.

Abstract: Provided is a light-emitting device which can emit monochromatic light with high purity due to a microcavity effect and which can emit white light in the case of a combination of monochromatic light. Provided is a high-definition light-emitting device. Provided is a light-emitting device with low power consumption. In a light-emitting device with a white-color filter top emission structure, one pixel is formed of four sub-pixels of RBGY, an EL layer includes a first light-emitting substance which emits blue light and a second light-emitting substance which emits light corresponding to a complementary color of blue, and a semi-transmissive and semi-reflective electrode (an upper electrode) is formed so as to cover an edge portion of the EL layer.

Abstract: A novel display device that is highly convenient with low power consumption is provided. The display device includes a display element including a liquid crystal layer, a display element including a light-emitting layer, and a pixel circuit. Electrodes of the display element including the liquid crystal layer and the display element including the light-emitting layer are electrically connected to the pixel circuit. The electrode of the display element including the liquid crystal layer includes a reflective film including an opening. The pixel circuit includes a transistor including a semiconductor film. The number of insulating films in a region overlapping with the opening is smaller than that of insulating films overlapping with the semiconductor film. In addition, the display element including the light-emitting layer includes two light-emitting elements.

Abstract: Provided is a light-emitting device which can emit monochromatic lights with high color purity due to a microcavity effect and which can provide a white light with a broad spectrum when the monochromatic lights are combined. The light-emitting device has a red-, green-, blue-, and yellow-emissive light-emitting elements each of which has a reflective electrode and a semi-transmissive and semi-reflective electrode. The red-, green-, blue-, and yellow-emissive light-emitting elements have the same structure other than the reflective electrode and a layer in contact with the reflective electrode to selectively emit red, green, blue, and yellow lights, respectively. Red, green, and blue color filters are also provided over the red-, green-, blue-, light-emitting elements, respectively. An EL layer is commonly shared by the red-, green-, blue-, and yellow-emissive light-emitting elements, and the semi-transmissive and semi-reflective electrode covers an edge portion of the EL layer.

Abstract: To provide a novel light-emitting device, a light-emitting device that emits light of a plurality of colors includes a first light-emitting element and a second light-emitting element. The first light-emitting element includes a first lower electrode, a first light-emitting layer over the first lower electrode, a second light-emitting layer over the first light-emitting layer, and an upper electrode over the second light-emitting layer. The second light-emitting element includes a second lower electrode, the first light-emitting layer over the second lower electrode, the second light-emitting layer over the first light-emitting layer, and the upper electrode over the second light-emitting layer. An emission spectrum of the first light-emitting layer peaks at a longer wavelength than an emission spectrum of the second light-emitting layer.

Abstract: A light-emitting element with which a reduction in power consumption and an improvement in productivity of a display device can be achieved is provided. A technique of manufacturing a display device with high productivity is provided. The light-emitting element includes an electrode having a reflective property, and a first light-emitting layer, a charge generation layer, a second light-emitting layer, and an electrode having a light-transmitting property stacked in this order over the electrode having a reflective property. The optical path length between the electrode having a reflective property and the first light-emitting layer is one-quarter of the peak wavelength of the emission spectrum of the first light-emitting layer. The optical path length between the electrode having a reflective property and the second light-emitting layer is three-quarters of the peak wavelength of the emission spectrum of the second light-emitting layer.

Abstract: An inverted-structure light-emitting element is provided. One embodiment of the invention disclosed in this specification is a light-emitting element including a cathode, a layer serving as a buffer over the cathode, an electron-injection layer over the layer serving as a buffer, a light-emitting layer over the electron-injection layer, and an anode over the light-emitting layer. The electron-injection layer includes an alkali metal or an alkaline earth metal. The layer serving as a buffer includes an electron-transport material. In the inverted-structure light-emitting element, contact of the alkali metal or alkaline earth metal included in a material of the electron-injection layer with the already formed cathode increases the driving voltage of an EL element and reduces emission efficiency. This problem becomes prominent particularly when the cathode includes an oxide conductive film. To prevent this, the layer serving as a buffer is provided between the cathode and the electron-injection layer.

Abstract: A novel light-emitting element is provided. A light-emitting element that emits red light with high color purity and has high emission efficiency is provided. A full-color light-emitting device having low power consumption is provided. In the light-emitting element that exhibits white light emission, the emission wavelength range of red light is a specific range on the longer wavelength side than the conventional emission wavelength range of red light that is usually used, and an optical element having a specific transmittance in the specific wavelength range is used.

Abstract: A light-emitting element having high external quantum efficiency is provided. A light-emitting element having a long lifetime is provided. A light-emitting element includes a light-emitting layer between a pair of electrodes. The light-emitting layer contains at least a phosphorescent compound, a first organic compound (host material) having an electron-transport property, and a second organic compound (assist material) having a hole-transport property. The light-emitting layer has a stacked-layer structure including a first light-emitting layer and a second light-emitting layer, and the first light-emitting layer contains a higher proportion of the second organic compound than the second light-emitting layer. In the light-emitting layer (the first light-emitting layer and the second light-emitting layer), a combination of the first organic compound and the second organic compound forms an exciplex.

Abstract: Emission efficiency of a light-emitting element is improved. The light-emitting element has a pair of electrodes and an EL layer between the pair of electrodes. The EL layer includes a first light-emitting layer and a second light-emitting layer. The first light-emitting layer includes a fluorescent material and a host material. The second light-emitting layer includes a phosphorescent material, a first organic compound, and a second organic compound. An emission spectrum of the second light-emitting layer has a peak in a yellow wavelength region. The first organic compound and the second organic compound form an exciplex.

Abstract: A technique of manufacturing a display device with high productivity is provided. In addition, a high-definition display device with high color purity is provided. By adjusting the optical path length between an electrode having a reflective property and a light-emitting layer by the central wavelength of a wavelength range of light passing through a color filter layer, the high-definition display device with high color purity is provided without performing selective deposition of light-emitting layers. In a light-emitting element, a plurality of light-emitting layers emitting light of different colors are stacked. The closer the light-emitting layer is positioned to the electrode having a reflective property, the shorter the wavelength of light emitted from the light-emitting layer is.

Abstract: Provided is a light-emitting device which can emit monochromatic light with high purity due to a microcavity effect and which can emit white light in the case of a combination of monochromatic light. Provided is a high-definition light-emitting device. Provided is a light-emitting device with low power consumption. In a light-emitting device with a white-color filter top emission structure, one pixel is formed of four sub-pixels of RBGY, an EL layer includes a first light-emitting substance which emits blue light and a second light-emitting substance which emits light corresponding to a complementary color of blue, and a semi-transmissive and semi-reflective electrode (an upper electrode) is formed so as to cover an edge portion of the EL layer.