Display device
A display device including a substrate and a plurality of pixels in a display region of the substrate. Each of the pixels includes first and second sub-pixels, and each of the first and second sub-pixels has a light emitting region for emitting light. The first sub-pixel includes a first light emitting element in the light emitting region and configured to emit visible light. The second sub-pixel includes a second light emitting element in the light emitting region and configured to emit infrared light and a light receiving element configured to receive the infrared light emitted from the second light emitting element to detect a user's touch. The second light emitting element and the light receiving element in the second sub-pixel are electrically insulated from and optically coupled to each other to form a photo-coupler.
1. A display device comprising:
a substrate having a display region and a non-display region; and
a plurality of pixels in the display region of the substrate, each of the pixels comprising first and second sub-pixels, each of the first and second sub-pixels having a light emitting region for emitting light,
wherein the first sub-pixel comprises a first light emitting element in the light emitting region, the first light emitting element being configured to emit visible light,
wherein the second sub-pixel comprises:
a second light emitting element in the light emitting region, the second light emitting element being configured to emit infrared light; and
a light receiving element configured to receive the infrared light emitted from the second light emitting element to detect a user's touch, and
wherein the second light emitting element and the light receiving element in the second sub-pixel are electrically insulated from and optically coupled to each other to form a photo-coupler.
2. A display device comprising:
a substrate having a display region and a non-display region; and
a plurality of pixels in the display region of the substrate, each of the pixels comprising first and second sub-pixels, each of the first and second sub-pixels having a light emitting region for emitting light,
wherein the first sub-pixel comprises a first light emitting element in the light emitting region, the first light emitting element being configured to emit visible light,
wherein the second sub-pixel comprises:
a second light emitting element in the light emitting region, the second light emitting element being configured to emit infrared light; and
a light receiving element configured to receive the infrared light emitted from the second light emitting element to detect a user's touch,
wherein the second light emitting element and the light receiving element in the second sub-pixel are electrically insulated from and optically coupled to each other to form a photo-coupler, and
wherein the second light emitting element comprises a rod-like light emitting diode configured to emit the infrared light, and the light receiving element comprises a photo diode configured to receive the infrared light.
3. The display device of claim 2 , wherein the first light emitting element emits light of one of red, green, blue, and white colors light.
4. The display device of claim 2 , wherein each of the first and second sub-pixels comprises a transistor on the substrate.
5. The display device of claim 4 , wherein the transistor comprises:
a semiconductor layer on the substrate;
a gate electrode on the semiconductor layer with a gate insulation layer therebetween; and
source and drain electrodes connected to the semiconductor layer.
6. The display device of claim 2 , wherein the light receiving element is configured to detect the infrared light emitted from the second light emitting element that is reflected from a user's finger and to convert the detected light into an electric signal.
7. The display device of claim 6 , wherein the second sub-pixel further comprises a read-out line for receiving the electric signal of the light receiving element.
8. The display device of claim 6 , wherein each of the first light emitting element, the second light emitting element, and the light receiving element comprises:
a first conductive semiconductor layer doped with a first conductive dopant;
a second conductive semiconductor layer doped with a second conductive dopant; and
an active layer between the first conductive semiconductor layer and the second conductive semiconductor layer.
9. The display device of claim 8 , wherein each of the first light emitting element and the second light emitting element comprises a light emitting diode having a cylindrical column or a polygonal column shape on a microscale or nanoscale size.
10. The display device of claim 2 , further comprising:
an insulation layer on the substrate, the second light emitting element, and the light receiving element; and
an overcoat layer on the insulation layer.
11. The display device of claim 10 , further comprising a light blocking pattern on the insulation layer in the second sub-pixel, the light blocking pattern having a first opening exposing a portion of the insulation layer corresponding to the second light emitting element and a second opening exposing a portion of the insulation layer corresponding to the light receiving element.
12. The display device of claim 11 , wherein the light blocking pattern blocks the infrared light emitted from the second light emitting element from being incident on the first sub-pixel that is adjacent to the second sub-pixel.
13. The display device of claim 12 , further comprising a light extracting layer on the overcoat layer and configured to focus light incident on the light receiving element.
14. The display device of claim 13 , wherein the light extracting layer comprises a lens portion corresponding to the light receiving element.
15. The display device of claim 10 , further comprising a light blocking pattern on the overcoat layer in the second sub-pixel, the light blocking pattern having a first opening exposing a portion of the overcoat layer corresponding to the second light emitting element and a second opening exposing a portion of the overcoat layer corresponding to the light receiving element.
16. The display device of claim 10 , wherein a light blocking pattern is not in the first sub-pixel.
17. The display device of claim 16 , wherein each of the second light emitting element and the light receiving element has a first end and a second end in a longitudinal direction, and
wherein the second end of the second light emitting element and the first end of the light receiving element face each other on the substrate.
18. The display device of claim 17 , further comprising:
a (1-1)th electrode on the substrate and adjacent to the first end of the second light emitting element;
a second electrode on the same plane as the (1-1)th electrode and between the second end of the second light emitting element and the first end of the light receiving element;
a (1-2)th electrode on the same plane as the second electrode and adjacent to the second end of the light receiving element;
a (1-1)th contact electrode electrically connected to the (1-1)th electrode and the first end of the second light emitting element;
a (1-2)th contact electrode electrically connected to the (1-2)th electrode and the second end of the light receiving element; and
a second contact electrode electrically connected to the second end of the second light emitting element and the first end of the light receiving element.
19. The display device of claim 18 , wherein the second contact electrode is in a layer different from the (1-1)th contact electrode and the (1-2)th contact electrode.
20. The display device of claim 19 , wherein the light blocking pattern overlaps the (1-1)th contact electrode, the (1-2)th contact electrode, and the second contact electrode when viewed in a plan view.
21. The display device of claim 17 , further comprising:
a (1-1)th electrode on the substrate and adjacent to the first end of the second light emitting element;
a (2-1)th electrode on the same plane as the (1-1)th electrode and adjacent to the second end of the second light emitting element;
a (2-2)th electrode on the same plane as the (2-1)th electrode and adjacent to the first end of the light receiving element;
a (1-2)th electrode on the same plane as the (2-2)th electrode and adjacent to the second end of the light receiving element;
a (1-1)th contact electrode electrically connected to the (1-1)th electrode and the first end of the second light emitting element;
a (1-2)th contact electrode electrically connected to the (1-2)th electrode and the second end of the light receiving element;
a (2-1)th contact electrode electrically connected to the second end of the second light emitting element and the (2-1)th electrode; and
a (2-2)th contact electrode electrically connected to the first end of the light receiving element and the (2-2)th electrode.
22. The display device of claim 21 , wherein the (2-1)th contact electrode and the (2-2)th contact electrode are spaced apart from each other on the substrate and are on the same layer.
23. A display device comprising:
a substrate having a display region and a non-display region;
a plurality of pixels in the display region of the substrate, each of the pixels comprising first to fourth sub-pixels, each of the first to fourth sub-pixels having a light emitting region for emitting light, each of the first to third sub-pixels comprising a first light emitting element in the corresponding light emitting region and configured to emit visible light, the fourth sub-pixel comprising a second light emitting element in the light emitting region and configured to emit infrared light and a light receiving element configured to receive the infrared light emitted from the second light emitting element to detect a user's touch;
an insulation layer on the first light emitting element, the second light emitting element, and the light receiving element; and
a light blocking pattern on the insulation layer in the fourth sub-pixel and having a first opening exposing a portion of the insulation layer corresponding to the second light emitting element and a second opening exposing a portion of the insulation layer corresponding to the light receiving element,
wherein the second light emitting element and the light receiving element are electrically insulated from and optically coupled to each other to form a photo-coupler.
24. The display device of claim 23 , wherein the second light emitting element comprises a rod-like light emitting diode configured to emit the infrared light, and the light receiving element comprises a photo diode configured to receive the infrared light.
25. The display device of claim 23 , wherein the light blocking pattern blocks the infrared light emitted from the second light emitting element from being incident on the first to third sub-pixels adjacent to the fourth sub-pixel.
26. The display device of claim 25 , wherein the light blocking pattern is not provided in the first to third sub-pixels.