35 results about "Singlet exciton" patented technology

The invention discloses an organic light-emitting device. According to the organic light-emitting device, a TADF material is used as a first host material of a green light unit to sensitize a green phosphorescent material used as a first guest material. Partial triplet excitons are subjected to reverse intersystem crossing to singlet excitons. The concentration of the triplet excitons decreases to enable a recombination region to become narrow, which avoids the diffusion of the triplet excitons to a blue light layer to emit light so as to realize that the green spectrum does not contain a blue light component. Because the energy level difference between the red light and the blue light is relatively large, and current carriers in the red light are not liable to spread into the blue light, the blue light component is not liable to appear in the red spectrum. Therefore, the red / green subpixel emission spectrum in a blue-light-layer-shared organic light-emitting device does not contain the blue light, which can effectively enlarge the combination selection range of luminescent materials and improve the display performance of the device. In addition, there is no need for providing a hole blocking layer, and the device structure is effectively simplified, so that operating voltage is reduced; and meanwhile, the difficulty of the process is reduced, and product yield is improved, so that production cost is reduced.

An organic electroluminescent device having at least one organic layer containing a light-emitting layer between a pair of electrodes, wherein the organic electroluminescent device contains a compound emitting fluorescence at a time that voltage is applied, and the light emission at the time that voltage is applied is mainly derived from the light emission of a fluorescent compound, and the external quantum efficiency of the device is 6% or more. It is preferable that the organic electroluminescent device contain an amplifying agent performing the function of amplifying the number of singlet excitons generated at the time that voltage is applied, thus amplifying the intensity of the light emission. The amplifying agent is a transition metal complex, in particular, an iridium complex, a platinum complex, a rhenium complex, a ruthenium complex, a palladium complex, a rhodium complex, a copper complex or a rare earth device complex. The compound emitting fluorescence is preferably a fused aromatic compound.

The maximum luminous efficiency of organic light-emitting materials is increased through spin-dependent processing. The technique is applicable to all electro-luminescent processes in which light is produced by singlet exciton decay, and all devices which use such effects, including LEDs, super-radiant devices, amplified stimulated emission devices, lasers, other optical microcavity devices, electrically pumped optical amplifiers, and phosphorescence (Ph) based light emitting devices. In preferred embodiments, the emissive material is doped with an impurity, or otherwise modified, to increase the spin-lattice relaxation rate (i.e., decrease the spin-lattice time), and hence raise the efficiency of the device. The material may be a polymer, oligomer, small molecule, single crystal, molecular crystal, or fullerene. The impurity is preferably a magnetic or paramagnetic substance. The invention is applicable to IR, UV, and other electromagnetic radiation generation and is thus not limited to the visible region of the spectrum. The methods of the invention may also be combined with other techniques used to improve device performance.

The invention discloses a malononitrile substituted aryl anthraphenanthrene organic electroluminescence material and its preparation method and application. The above organic electroluminescent material uses malononitrile substituted aryl anthraphenanthrene as the mother nucleus, and its structural formula As shown in formula (I). The malononitrile-substituted aryl anthraphenanthrene organic electroluminescent material provided by the invention has a simple preparation process, HOMO and LUMO energy level electron clouds can be effectively separated, and the singlet-triplet energy gap (ΔE ST ) is small, the triplet excitons can be transformed into singlet excitons by reverse intersystem jumping (RIST) to emit light, and have thermally activated delayed fluorescence properties; High device efficiency is obtained when applied to OLED light-emitting devices.

To provide a novel fluorescent organic compound (a fluorescent compound). The organic compound is a substance that emits fluorescence and an organic compound (a host material) in which TTA can occur efficiently. In the organic compound, triplet excitons, which do not contribute to light emission, can be efficiently converted into singlet excitons. The use of such an organic compound can increase emission efficiency of a light-emitting element.