LIGHT-CONVERSION MATERIAL AND LIGHT-EMITTING DEVICE AND DISPLAY DEVICE INCLUDING THE SAME
A light-conversion material and a light-emitting device and a display device including the same are provided. The light-conversion material is represented by formula (I): M m D d A a C c E e G g :R r (I). Wherein M is Ca, Sr, or Ba; D is Zn, Cd, or a combination thereof; A is B, Al, or Ga; C is Si; E is O, S, or Se; G is N, P, As, Sb, or Bi; and R is Eu, Sm, or Yb. The formula (I) is satisfied by 0.5≤m≤2; 1≤d≤4; 0≤a≤2; 0.1≤c≤3.5; 0.1≤e≤4; 0.5≤g≤5.5; and 0.1≤r≤1.
1 . A light-conversion material, represented by formula (I):
MmDdAaCcEeGg:Rr (I),
wherein:
M is Ca, Sr, or Ba;
D is Zn, Cd, or a combination thereof,
A is B, Al, or Ga;
C is Si;
E is O, S, or Se;
G is N, P, As, Sb, or Bi;
R is Eu, Sm, or Yb;
0.5<m<2;
1<d<4;
0<a<2;
0.1<c<3.5;
0.1<e<4;
0.5<g<5.5; and
0.1<r<1.
2 . The light-conversion material as claimed in claim 1 , wherein c/d<3.
3 . The light-conversion material as claimed in claim 2 , wherein c/d<1.
4 . The light-conversion material as claimed in claim 3 , wherein c/d<0.5.
5 . The light-conversion material as claimed in claim 1 , wherein e/d<2.
6 . The light-conversion material as claimed in claim 5 , wherein e/d<1.5.
7 . The light-conversion material as claimed in claim 6 , wherein e/d<0.83.
8 . The light-conversion material as claimed in claim 1 , wherein d/r>2.
9 . The light-conversion material as claimed in claim 8 , wherein d/r>4.8.
10 . The light-conversion material as claimed in claim 9 , wherein d/r>9.
11 . The light-conversion material as claimed in claim 1 , wherein c/r<6.
12 . The light-conversion material as claimed in claim 11 , wherein c/r<1.2.
13 . The light-conversion material as claimed in claim 1 , wherein c/m<6.
14 . The light-conversion material as claimed in claim 13 , wherein c/m<0.55.
15 . The light-conversion material as claimed in claim 1 , wherein the light-conversion material absorbs a light in a wavelength range above 400 nm and below 480 nm to emit a green light, the green light has an emission peak wavelength in a range above 480 nm and below 580 nm, and the green light has a maximum emission intensity, wherein:
when an emission intensity is 50% of the maximum emission intensity, a difference between a maximum value and a minimum value of an emission wavelength of the light-conversion material is D50,
when an emission intensity is 10% of the maximum emission intensity, a difference between a maximum value and a minimum value of the emission wavelength of the light-conversion material is D10, and 2.5 D50<D10<5.5 D50.
16 . A light-emitting device, comprising:
a light source emitting an excitation light, wherein the excitation light has an emission peak wavelength in a range above 400 nm and below 480 nm; and
a light-conversion material as claimed in claim 1 , wherein the light-conversion material absorbs a portion of the excitation light to emit a green light, the green light has an emission peak wavelength in a range above 480 nm and below 580 nm, and the green light has a maximum emission intensity, wherein:
when an emission intensity is 50% of the maximum emission intensity, a difference between a maximum value and a minimum value of an emission wavelength of the light-conversion material is D50,
when an emission intensity is 10% of the maximum emission intensity, a difference between a maximum value and a minimum value of the emission wavelength of the light-conversion material is D10, and 2.5 D50<D10<5.5 D50.
17 . The light-emitting device as claimed in claim 16 , further comprising a first wavelength conversion portion including the light-conversion material and a second wavelength conversion portion including another light-conversion material, wherein the second wavelength conversion portion covers the light source and the first wavelength conversion portion is on the second wavelength conversion portion.
18 . The light-emitting device as claimed in claim 17 , further comprising a protection layer on the first wavelength conversion portion.
19 . A display device, comprising a light-emitting device as claimed in claim 16 .
20 . The display device as claimed in claim 19 , further comprising another light-conversion material absorbs a portion of the excitation light to emit a red light.