Provided are a light-emitting device including a heterocyclic compound represented by Formula 1 below and an electronic apparatus including the light-emitting device. The detailed description of Formula 1 is the same as described in the present specification.

##STR00001##

An light emitting device of the present embodiments includes oppositely disposed first electrode and second electrode, and a plurality of organic layers disposed between the first electrode and the second electrode, wherein at least one among the plurality of organic layers includes a fused polycyclic compound represented by Formula 1 below, thereby showing improved emission efficiency:

##STR00001##

A light-emitting element having high emission efficiency is provided. The light-emitting element includes a first organic compound, a second organic compound, and a third organic compound. The first organic compound has a function of converting triplet excitation energy into light emission. The second organic compound is preferably a TADF material. The third organic compound is a fluorescent compound. Light emitted from the light-emitting element is obtained from the third organic compound. Triplet excitation energy in a light-emitting layer is transferred to the third organic compound by reverse intersystem crossing caused by the second organic compound or through the first organic compound.

An embodiment of the present disclosure provides an organic light emitting diode comprising a first electrode; a second electrode facing the first electrode; and a first emitting material layer including a first delayed fluorescent dopant and a first phosphorescent dopant and disposed between the first and second electrodes, wherein a percentage by weight of the first phosphorescent dopant with respect to the first delayed fluorescent dopant is equal to or less than 5.

Provided is a new composition of matter for boron containing organic molecules which can be used as hosts or emitters in OLED devices. The compound can have a structure of Formula I ##STR00001##

Disclosed is an organometallic compound represented by a following Chemical Formula 1. The organometallic compound acts as a dopant of a light-emitting layer of an organic light-emitting diode. Thus, operation voltage of the diode is lowered, and luminous efficiency and lifespan thereof are improved:

Ir(L.sub.A).sub.m(L.sub.B).sub.n  [Chemical Formula 1] where in the Chemical Formula 1, L.sub.A represents a main ligand, and is one selected from a group consisting of Chemical Formula 2-1, Chemical Formula 2-2, and Chemical Formula 2-3, L.sub.B denotes an ancillary ligand represented by a Chemical Formula 3, each of m and n denotes a number of the ligands bound to Ir (iridium), and m is 1, 2 or 3, and n is 0, 1 or 2, and a sum of m and n is 3.

This organic electroluminescence element includes an anode, a cathode, and an organic layer disposed between the anode and the cathode. The organic layer includes a light-emitting layer and at least one layer disposed between the light-emitting layer and the anode. The light-emitting layer includes a compound represented by formula (1), and the at least one layer disposed between the light-emitting layer and the anode includes a compound represented by formula (2). ##STR00001##

An organometallic compound represented by Formula 1:

M.sub.1(L.sub.11).sub.n11(L.sub.12).sub.n12   Formula 1

wherein, in Formula 1, M.sub.1 is a first-row transition metal of the Periodic Table of Elements, a second-row transition metal of the Periodic Table of Elements, or a third-row transition metal of the Periodic Table of Elements, L.sub.11 is a ligand represented by Formula 1-1, L.sub.12 is a monodentate ligand or a bidentate ligand, n11 is 1, and n12 is 0, 1, or 2:

##STR00001##

wherein the other substituents are as described in the detailed description.

A light emitting element according to an embodiment includes a first electrode, a second electrode disposed on the first electrode, and an emission layer disposed between the first electrode and the second electrode. The emission layer comprises a first compound, a second compound, and a third compound, which are different from each other, and the first compound is a polycyclic compound represented by Formula 1, thereby achieving a light emitting element having high emission efficiency.

##STR00001##

Provided is an organic light-emitting device including: a first electrode; a second electrode facing the first electrode; and an emission layer between the first electrode and the second electrode and including a host and a phosphorescent dopant, wherein a photoluminescence (PL) spectrum of the emission layer may include a first peak (I.sub.max) having a maximum intensity and a second peak (I.sub.2nd) having a second highest intensity, and a rate of change of an intensity of the second peak of the emission layer may be greater than 0 percent (%) of an intensity of a second peak of a PL spectrum of the phosphorescent dopant.