Provided is a light emitting element includes a polycyclic compound in which an electron donor substituent, which may increase the photoluminescence quantum yield (PLQY) and oscillator strength (f), is introduced at the para-position of a boron atom, thereby exhibiting high efficiency and long service life characteristics.

A light emitting diode of an embodiment includes a first electrode, a second electrode, and at least one functional layer between the first electrode and the second electrode, wherein the at least one functional layer includes at least one selected from among a polycyclic compound represented by Formula 1 and a compound represented by Formula E-1.

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An organic light-emitting diode and a preparation method therefore, a display panel and a display device. The organic light-emitting diode comprises an anode (300); a light-emitting layer (200); and a cathode (100), wherein the light-emitting layer (200) is internally provided with a doping material and at least two types of host materials, and a horizontal alignment factor of the light-emitting layer (200) is not less than 65%.

Discussed is a light-emitting device including a first light-emitting layer so that a dopant having a hole trapping property is adjacent to a hole transport layer, and a second light-emitting layer that comes into contact with the first light-emitting layer to induce main light emission, thereby widening an emission zone and improving the efficiency and lifespan of the light-emitting layer. Also discussed is a light-emitting display including the light-emitting device. The first and second blue light-emitting layers can include a same host BH and different first and second blue dopants, respectively, and the first blue dopant can have a higher highest occupied molecular orbital (HOMO) energy level than a HOMO energy level of the hole transport layer.

A light emitting device and a light emitting display including the same. The light emitting device includes an anode and a cathode facing each other, a first stack and a second stack disposed between the anode and the cathode, the first stack including a first electron transport layer comprising a first material represented by Formula 1, a first blue light emitting layer containing a boron-based compound emitting light having a wavelength of 430 nm to 480 nm, and a first electron-blocking layer including a second material including a spirofluorene group, and at least one hydrogen atom on at least one side of the spirofluorene group is substituted by deuterium, and the second stack including at least two phosphorescent light emitting layers emitting light having a longer wavelength than that of the light emitted by the first blue light emitting layer, and a charge generation layer.

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Disclosed is a light emitting device that is capable of reducing lateral leakage current and a driving voltage by improving a structure for connecting a plurality of stacks to one another in a structure using the plurality of stacks, and a light emitting display device including the same. The light emitting device includes a first electrode and a second electrode facing each other, a plurality of stacks provided between the first electrode and the second electrode, and a charge generation layer including an electron generation layer and a hole generation layer stacked between the stacks, wherein the electron generation layer contains a first host of Formula 1 and a metal dopant, and the hole generation layer contains a second host and an organic dopant.

A light emitting element includes a first electrode, a second electrode, and an emission layer between the first electrode and the second electrode and includes a compound represented by Formula 1 below, thereby exhibiting a long service life characteristic.

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Embodiments provide an organometallic compound, a light-emitting device including the organometallic compound, and an electronic apparatus including the light-emitting device. The light-emitting device includes a first electrode, a second electrode facing the first electrode, an interlayer between the first electrode and the second electrode and including an emission layer, and the organometallic compound, which is represented by Formula 1.

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The description of Formula 1 is provided in the specification.

Provided are organometallic compounds having a structure of

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Also provided are formulations that include these organometallic compounds. Further provided are OLEDs and related consumer products that utilize these organometallic compounds.

Provided are a polycyclic compound represented by Formula 1, an organic light-emitting device including the polycyclic compound, and an electronic apparatus including the organic light-emitting device:

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Formula 1 may be understood by referring to the description of Formula 1 provided herein.