The present invention discloses a display panel, which includes a display unit. The display unit includes an anode layer, a hole injection layer, a hole transport layer, a luminescent material layer, an electron transporting layer, an electron injection layer, a cathode layer. The luminescent material layer includes the first luminescent material block, the second luminescent material block, and the third luminescent material block. The first luminous material block and the second luminous material block are partially overlapped, and the second luminous material block and the third luminescent material block are partially overlapped. The present invention is beneficial to producing a pixel having a smaller dimension in the display panel.

A compound of Chemical Formula 1:

##STR00001##

and an organic light emitting device including the same.

Provided a light emitting device including a first metal reflection layer including a phase modulation surface configured to magnetically resonate incident light, a color conversion layer provided on the phase modulation surface of the first metal reflection layer and including a photoluminescent material, a first electrode provided on the color conversion layer opposite to the first metal reflection layer, a white organic light emitting layer provided on the first electrode opposite to the color conversion layer, and a second electrode provided on the white organic light emitting layer opposite to the first electrode.

The present invention discloses an organic compound and an organic electroluminescence device using the organic compound as a material in the light emitting layer of the organic electroluminescence device. The organic compound may be for lowering a driving voltage, power consumption or increasing a current efficiency or 90% life time of the organic electroluminescence device. ##STR00001## The same definition as described in the present invention.

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.

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##

A white light emitting device and a light emitting display device including the same, in which the relationship between the triplet energy levels of dopants of emission layers is appropriately adjusted so as to improve the efficiency of the white light emitting device and the light emitting display device, thereby increasing a color temperature and enabling rich color representation.

A display apparatus including a light-emitting layer is provided. The light-emitting layer may be disposed between a first electrode and a second electrode. The light-emitting layer may include a first emission stack and a second emission stack on the first emission stack. The first emission stack may include a blue emission material layer. The second emission stack may include an emission buffer layer, a first phosphorescent emission material layer and a second phosphorescent emission material layer, which are sequentially stacked. The emission buffer layer may include a host having an electron transporting properties and a red dopant. The content of the red dopant in the emission buffer layer may decrease as a distance from the first charge generation layer increases. Thus, in the display apparatus, a color change at low-current may be improved.

Provided is a compound of Chemical Formula 1: ##STR00001## wherein: each X is independently N or CH, with the proviso that at least one X is N; Y is O or S; L.sub.1 and L.sub.2 are each independently a single bond, a substituted or unsubstituted C.sub.6-60 arylene, or a substituted or unsubstituted C.sub.2-60 heteroarylene containing at least one heteroatom selected from the group consisting of N, O, and S; Ar.sub.1 and Ar.sub.2 are each independently a substituted or unsubstituted C.sub.6-60 aryl, or a substituted or unsubstituted C.sub.2-60 heteroaryl containing at least one heteroatom selected from the group consisting of N, O, and S; and Ar.sub.3 is a substituted or unsubstituted C.sub.6-60 aryl, or a substituted or unsubstituted C.sub.2-60 heteroaryl containing at least one heteroatom selected from the group consisting of N, O, and S; and to an organic light emitting device including the same.

The present invention relates to a light-emitting layer B comprising a first emitter compound (a) having a non-exited state S0(a), a first excited singlet state S1(a) and a first excited triplet state T1(a); a second emitter compound (b) having a non-exited state S0(b), a first excited singlet state S1(b) and a first excited triplet state T1(b), wherein the energy level of S1(a) is higher than that of S1(b), the energy level of S1(b) is higher than that of T1(b) and wherein the rate of reverse intersystem crossing from T1(a) to S1(a) is higher than the rate of excitation energy transfer from S1(a) to S1(b) and/or the rate of excitation energy transfer from T1(a) to T1(b), and/or wherein the energy level of T1(b) is higher than that of T1(a). Further, the present invention also refers to an opto-electronic device comprising such light-emitting layer B and use thereof.