Display apparatus

1. A display apparatus comprising:

an organic light emitting diode (OLED) structure comprising at least one blue light-emitting unit configured to emit blue incident light, and at least one green light-emitting unit configured to emit green incident light, which are stacked and to provide incident light in which the blue incident light and the green incident light are mixed;

a first pixel, a second pixel, and a third pixel disposed on the OLED structure, and respectively configured to emit a first color light, a second color light, and a third color light;

at least two color conversion layers each separately disposed on at least two of the first, the second, or the third pixels, and including quantum dots for converting the incident light from the OLED structure into light of a predetermined color; and

first, second, and third color filters disposed on the first, the second, and the third pixels, respectively, to absorb or block light of a predetermined wavelength band, wherein

a conversion value of an area of a spectrum in a wavelength region of 380 nanometers to 780 nanometers of the green incident light with respect to a difference between a maximum transmittance wavelength of the second color filter and the medial wavelength of the green incident light (Δλ) is about 3.6 or greater and about 13 or less,

wherein the area of the spectrum is determined according to Equation 1 below,

Area

=

∫

380

780

⁢

f

⁡

(

x

)

⁢

⁢

dx

≈

∑

n

=

1

n

-

1

⁢

1

2

⁢

(

x

n

+

1

-

x

n

)

⁡

[

f

⁡

(

x

n

+

1

)

+

f

⁡

(

x

n

)

]

⁢

⁢

⁢

(

x

1

=

380

⁢

⁢

nm

,

x

n

=

780

⁢

⁢

nm

)

Equation

⁢

⁢

1

wherein in Equation 1, f(x) is a spectrum of the green incident light in which the maximum value of the light intensity is normalized to 1, and the medial wavelength is a wavelength that divides the area of the spectrum of the green incident light into two equal halves, and

the conversion value R is determined according to Equation 3 below.

R =Area/Δλ  Equation 3

2. The display apparatus of claim 1 , wherein the OLED structure has a tandem structure.

3. The display apparatus of claim 1 , wherein

the OLED structure comprises a first blue light-emitting unit, a green light-emitting unit, and a second blue light-emitting unit sequentially stacked, wherein

the green light-emitting unit is disposed between the first and second blue light-emitting units.

4. The display apparatus of claim 3 , further comprising:

a first charge generation layer disposed between the first blue light-emitting unit and the green light-emitting unit, and

a second charge generation layer disposed between the green light-emitting unit and the second blue light-emitting unit.

5. The display apparatus of claim 1 , wherein the green light-emitting unit comprises an organic material-based green light-emitting layer, and the green light-emitting layer comprises a thermally activated delayed fluorescence (TADF) dopant.

6. The display apparatus of claim 1 , wherein the green light-emitting unit comprises an organic material-based green light emitting layer, and the green light-emitting layer comprises a phosphorescent dopant, wherein

the phosphorescent dopant satisfies T1(dopant)≤S1(dopant)≤T1(dopant)+0.5 eV, where T1 (dopant) is a triplet energy level in eV and S1 (dopant) is a singlet energy level in eV of the phosphorescent dopant.

7. The display apparatus of claim 6 , wherein the phosphorescent dopant is an organometallic compound including iridium Ir.

8. The display apparatus of claim 6 , wherein the phosphorescent dopant is an organometallic compound including platinum Pt, osmium Os, titanium Ti, zirconium Zr, hafnium Hf, europium Eu, terbium Tb, thulium Tm, rhodium Rh, ruthenium Ru, rhenium Re, beryllium Be, magnesium Mg, aluminum Al, calcium Ca, manganese Mn, cobalt Co, copper Cu, zinc Zn, gallium Ga, germanium Ge, rhodium Rh, palladium Pd, silver Ag, or gold Au.

9. The display apparatus of claim 6 , wherein the phosphorescent dopant is an organometallic compound having a square-planar coordination structure.

10. The display apparatus of claim 6 , wherein the phosphorescent dopant comprises a metal and an organic ligand, wherein the metal and the organic ligand form one, two, or three cyclometallated rings.

11. The display apparatus of claim 6 , wherein

the phosphorescent dopant comprises a metal and a four-coordinate organic ligand capable of forming 3 or 4 cyclometallated rings,

the metal comprises platinum Pt, osmium Os, titanium Ti, zirconium Zr, hafnium Hf, europium Eu, terbium Tb, thulium Tm, rhodium Rh, ruthenium Ru, rhenium Re, beryllium Be, magnesium Mg, aluminum Al, calcium Ca, manganese Mn, cobalt Co, copper Cu, zinc Zn, gallium Ga, germanium Ge, rhodium Rh, palladium Pd, silverAg, or gold Au, and

the four-coordinate organic ligand includes a benzimidazole group or a pyridine group.

12. The display apparatus of claim 1 , wherein the first color filter is a blue and green cut filter, and the second color filter is a blue cut filter.

13. The display apparatus of claim 1 , wherein the first color filter is an absorption-type red color filter, and the second color filter is an absorption-type green color filter.

14. The display apparatus of claim 1 , wherein the third color filter is a green cut filter or an absorption type blue color filter.

15. The display apparatus of claim 1 , wherein the display apparatus further comprises a fourth pixel configured to emit light of a color different from that of the first, second, or third pixels.

16. The display apparatus of claim 15 , wherein the fourth pixel is a blank region.