Novel electroluminescent devices containing bicarbazole triazine compounds as emissive dopants are described. Devices incorporating this class of compounds exhibit delayed fluorescence characteristics that showed EQE's far exceeding the theoretical limit for a conventional fluorescent device.

Matrix display device (100) having organic electroluminescent layers, successively comprising: a substrate, a first control electrode (101), a first light-emitting assembly comprising at least a first organic electroluminescent layer (104), a second light-emitting assembly comprising at least a second organic electroluminescent layer (106), a second electrode (102) that has opposite polarity to said first electrode and that is at least partially transparent with respect to the light emitted by said electroluminescent layers; said control electrode (101) being structured to form a display matrix; said device being characterized in that the product of the mean refraction index of the organic layers and the distance between the surface opposite the substrate of said control electrode (101) and the surface at the substrate side of said second electrode (102) is between 125 nm and 205 nm.

The present invention relates to organic electroluminescent devices comprising a light-emitting layer B comprising a host material, a phosphorescence material and a emitter material, which exhibits a narrow—expressed by a small full width at half maximum (FWHM)—green emission at an emission maximum of 500 to 560 nm. Further, the present invention relates to a method for generating green light by means of an organic electroluminescent device according to the present invention.

A light emitting device having an anode, a cathode, a first organic layer disposed between the anode and the cathode and a second organic layer disposed between the anode and the cathode is provided. The first organic layer is a layer containing a compound (T) in which the absolute value of the difference between the energy level at the lowest triplet excited state and the energy level at the lowest singlet excited state is 0.5 eV or less and not containing a phosphorescent metal complex. The second organic layer is a layer containing a crosslinked body of a polymer compound containing a crosslink constitutional unit and the energy level at the lowest triplet excited state of the polymer compound is 2.25 eV or more.

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. The light-receiving device has a function of absorbing at least part of visible light and infrared light.

A light-emitting device and an electronic apparatus including the same are provided.

Provided is a light-emitting element which includes a first electrode, a second electrode over the first electrode, and first and second light-emitting layers therebetween. The first light-emitting layer contains a first host material and a first light-emitting material, and the second light-emitting layer contains a second host material and a second light-emitting material. The first light-emitting material is a fluorescent material, and the second light-emitting material is a phosphorescent material. The level of the lowest triplet excited state (T.sub.1 level) of the first light-emitting material is higher than the T.sub.1 level of the first host material. A light-emitting device, an electronic device, and a lighting device including the light-emitting element are further provided.

The present invention relates to organic electroluminescent devices comprising a light-emitting layer B comprising a host material, a phosphorescence material and a emitter material, which exhibits a narrow—expressed by a small full width at half maximum (FWHM)—green emission at an emission maximum of 500 to 560 nm. Further, the present invention relates to a method for generating green light by means of an organic electroluminescent device according to the present invention.

Provided is a light-emitting element including a fluorescence-emitting material with high emission efficiency. The light-emitting element includes a pair of electrodes and an EL layer between the pair of electrodes. The EL layer includes a first organic compound, a second organic compound, and a guest material. The first organic compound has a function of emitting a thermally activated delayed fluorescence at room temperature. The guest material has a function of emitting fluorescence. A HOMO level of the first organic compound higher than or equal to a HOMO level of the second organic compound. A LUMO level of the first organic compound is lower than or equal to a LUMO level of the second organic compound.

Disclosed are an organic light emitting display device and lighting apparatus for vehicles using the same. The organic light emitting display device includes a first layer including a first organic layer and a first emission layer on a first electrode, a second layer including a second emission layer and a second organic layer on the first layer, a second electrode on the second layer, and a third organic layer between the first layer and the second layer. A thickness of the first emission layer is equal to or greater than a thickness of each of the first organic layer and the second organic layer.