Color conversion element and display device including the same

1. A color conversion element, comprising:

a base substrate in which a first region and a second region are defined;

a color conversion layer on the base substrate, in the first region, and comprising color conversion particles configured to convert a wavelength of incident light;

a color light transmitting layer on the base substrate in the second region;

a color filter layer between the color conversion layer and the base substrate, on which light emitted from the color conversion layer is incident, and which is configured to block a part of the light;

a first capping layer and a second capping layer disposed between the color filter layer and the color conversion layer;

a first low refractive layer disposed between the first capping layer and the second capping layer;

a third capping layer and a fourth capping layer disposed on the color conversion layer; and

a second low refractive layer disposed between the third capping layer and the fourth capping layer;

wherein each of the color conversion particles comprises a compound represented by Formula 1:

A m B n X l   (1)

in Formula 1, A is Cs, Rb, or an alloy thereof; B is at least one selected from the group consisting of Cu, Sb, Ge, Sn, Bi, and an alloy thereof; m, n, and l are each an integer of 1 to 9; and X is at least one selected from the group consisting of F, Cl, Br, I, and a mixture thereof,

wherein the compound is free of Pb,

the first, second, third and fourth capping layer include inorganic insulating material, and

the first and second low refractive layer include organic insulating material.

2. The color conversion element of claim 1 ,

wherein each of the color conversion particles has a polygonal or linear structure.

3. The color conversion element of claim 2 ,

wherein a length of the color conversion particle measured in a first direction is longer than a length of the color conversion particle measured in a second direction perpendicular to the first direction, and the length of the color conversion particle measured in the second direction perpendicular to the first direction is greater than a thickness of the color conversion particle.

4. The color conversion element of claim 3 ,

wherein the length of the color conversion particle measured in the first direction is in a range of 2 nm to 300 nm, and the thickness of the color conversion particle is in a range of 0.5 nm to 5 nm.

5. The color conversion element of claim 1 ,

wherein the color conversion layer comprises a light transmitting resin that does not absorb the incident light.

6. The color conversion element of claim 5 ,

wherein the color conversion particles are dispersed in the light transmitting resin in a state where at least one particle is aggregated with another particle adjacent thereto.

7. The color conversion element of claim 5 ,

wherein the low refractive layer has a lower refractive index than the light transmitting resin of the color conversion layer.

8. The color conversion element of claim 1 , wherein the color conversion layer comprises a first color conversion layer comprising first color conversion particles on which a first light having a center wavelength band of a first wavelength is incident and which convert the first light into a second light having a center wavelength band of a second wavelength longer than the first wavelength.

9. The color conversion element of claim 8 ,

wherein the color filter layer comprises a first color filter layer between the first color conversion layer and the base substrate, and the first color filter layer is configured to transmit the second light and to block the first light.

10. The color conversion element of claim 9 ,

wherein the color conversion layer further comprises a second color conversion layer comprising second color conversion particles configured to convert the first light into third light having a center wavelength band of a third wavelength longer than the second wavelength, and

the color filter layer further comprises a second color filter layer between the second color conversion layer and the base substrate.

11. The color conversion element of claim 10 ,

wherein, in Formula 1, the Xs of the first color conversion particles and the second conversion particles are different from each other.

12. The color conversion element of claim 10 ,

wherein the second color filter layer is configured to transmit the third light and to block the first light and the second light.

13. The color conversion element of claim 10 ,

wherein the second color conversion layer further comprises a quantum dot material.

14. The color conversion element of claim 10 ,

wherein when the first light is emitted, the first light is incident on the color light transmitting layer, the color filter layer further comprises a third color filter layer between the color light transmitting layer and the base substrate, the color light transmitting layer configured to emit the first light to the third color filter layer, and the third color filter layer is configured to transmit the first light and to block the second light and the third light.

15. The color conversion element of claim 1 , further comprising:

an optical filter layer on a surface other than an outer surface of the color conversion layer, contacting the base substrate, and configured to reflect light emitted from the color conversion layer.

16. The color conversion element of claim 15 ,

wherein the optical filter layer is configured to transmit at least a part of light incident on the color conversion layer or emitted from the color conversion layer, and configured to reflect other parts of the light.

17. A display device comprising:

a display element; and

a color conversion element on the display element,

wherein the color conversion element comprises:

a base substrate in which a first region and a second region are defined;

a color conversion layer on the base substrate, in the first region, and comprising color conversion particles configured to convert a wavelength of incident light;

a color light transmitting layer on the base substrate and in the second region;

a color filter layer between the color conversion layer and the base substrate, on which light emitted from the color conversion layer is incident, and which is configured to block a part of the light;

a first capping layer and a second capping layer disposed between the color filter layer and the color conversion layer;

a first low refractive layer disposed between the first capping layer and the second capping layer;

a third capping layer and a fourth capping layer disposed on the color conversion layer; and

a second low refractive layer disposed between the third capping layer and the fourth capping layer;

wherein each of the color conversion particles comprises a compound represented by Formula 1:

A m B n X l   (1)

in Formula 1, A is Cs, Rb, or an alloy thereof; B is at least one selected from the group consisting of Cu, Sb, Ge, Sn, Bi, and an alloy thereof; m, n, and l are each an integer of 1 to 9; and X is at least one selected from the group consisting of F, Cl, Br, I, and a mixture thereof,

wherein the compound is free of Pb,

the first, second, third and fourth capping layer include inorganic insulating material, and

the first and second low refractive layer include organic insulating material.

18. The display device of claim 17 ,

wherein each of the color conversion particles has a polygonal or linear structure.

19. The display device of claim 18 ,

wherein a length of the color conversion particle measured in a first direction is longer than a length of the color conversion particle measured in a second direction perpendicular to the first direction, and the length of the color conversion particle measured in the second direction perpendicular to the first direction is greater than a thickness of the color conversion particle.

20. The display device of claim 19 ,

wherein the length of the color conversion particle measured in the first direction is in a range of 2 nm to 300 nm, and the thickness of the color conversion particle is in a range of 0.5 nm to 5 nm.

21. The display device of claim 17 ,

wherein the color conversion layer includes a light transmitting resin configured not to absorb the incident light.

22. The display device of claim 21 ,

wherein the color conversion particles are dispersed in the light transmitting resin in a state where at least one particle is aggregated with another particle adjacent thereto.

23. The display device of claim 17 ,

wherein the color conversion layer comprises:

a first color conversion layer comprising first color conversion particles on which first light having a center wavelength band of a first wavelength is to be incident and which are configured to convert the first light into second light having a center wavelength band of a second wavelength longer than the first wavelength; and

a second color conversion layer including second color conversion particles configured to convert the first light into third light having a center wavelength band of a third wavelength longer than the second wavelength.

24. The display device of claim 23 ,

wherein, in Formula 1, the Xs of the first color conversion particles and the second conversion particles are different from each other.

25. The display device of claim 17 ,

wherein the display element comprises:

a first substrate;

a second substrate facing the first substrate;

a liquid crystal layer between the first substrate and the second substrate; and

a light source located opposite to the light conversion element with respect to the liquid crystal layer.

26. The display device of claim 17 ,

wherein the display element comprises:

a first electrode;

a hole transporting layer on the first electrode;

a light emitting layer on the hole transporting layer; and

a second electrode on the light emitting layer.