Display device using semiconductor light emitting devices having different structures
A display device using semiconductor light emitting devices is disclosed. The display device includes a substrate, a plurality of first electrodes disposed on the substrate, a light emitting device array comprising a plurality of semiconductor light emitting devices electrically connected to the first electrodes, constituting individual pixels, and having different brightnesses increasing from one side of a current input direction of each of the first electrodes to the other side of the current input direction, and a plurality of second electrodes electrically connected to the semiconductor light emitting devices. Thus, brightness variation caused by power loss may be reduced in a display device of PM type using light emitting device array, thereby reducing load effect that is a problem of the device of PM type using light emitting device array.
1. A display device using a semiconductor light emitting device comprising:
a substrate;
a plurality of first electrodes disposed on the substrate;
a light emitting device array comprising a plurality of semiconductor light emitting devices electrically connected to the first electrodes, constituting individual pixels, and having different brightnesses increasing from one side of a current input direction of each of the first electrodes to the other side of the current input direction, wherein the semiconductor light emitting devices comprise a semiconductor structure including an active layer, a p-type electrode disposed on a surface of the semiconductor structure and an n-type electrode disposed on another surface of the semiconductor structure;
a plurality of second electrodes electrically connected to the semiconductor light emitting devices; and
a wavelength converting layer disposed on the semiconductor light emitting devices,
wherein a distance between the n-type electrode and the p-type electrode of one of the semiconductor light emitting devices is different from a distance between the n-type electrode and the p-type electrode of another semiconductor light emitting device, and
wherein a distance between the n-type electrode and the p-type electrode of the semiconductor light emitting devices decreases from one side of a current input direction of each of the first electrodes to the other side of the current input direction.
2. The display device according to claim 1 , wherein the first electrodes and the second electrodes are aligned to be perpendicular to each other, respectively.
3. The display device according to claim 1 , wherein a brightness of at least some of the semiconductor light emitting devices linearly increases from one side of the current input direction of each of the first electrode to the other side of the current input direction.
4. The display device according to claim 3 , wherein a difference between a brightness of a first semiconductor light emitting device from the current input direction of each of the first electrodes and a brightness of a second semiconductor light emitting device from the current input direction is greater than a linearly increased value.
5. The display device according to claim 1 , wherein the semiconductor structure comprises:
an n-type semiconductor layer electrically connected to the n-type electrode;
the active layer disposed on the n-type semiconductor layer; and
a p-type semiconductor layer disposed on the active layer electrically connected to the p-type electrode.
6. The display device according to claim 5 , wherein a distance between the n-type electrode and the p-type semiconductor layer of each of the semiconductor light emitting devices decreases from one side of a current input direction of each of the first electrodes to the other side of the current input direction.
7. The display device according to claim 6 , wherein the distance between the n-type electrode and the p-type semiconductor layer of some of the semiconductor light emitting devices linearly decreases from one side of the current input direction of each of the first electrodes to the other side of the current input direction.
8. The display device according to claim 7 , wherein a difference between the distance between the n-type electrode and the p-type semiconductor layer of a first semiconductor light emitting device from the current input direction of the first electrode and the distance between the n-type electrode and the p-type semiconductor layer of a second semiconductor light emitting device from the current input direction of the first electrode is greater than a linearly decreased value.
9. The display device according to claim 8 , wherein the p-type semiconductor layers of the semiconductor light emitting devices have the same length.
10. The display device according to claim 1 , wherein the substrate is a transparent flexible substrate.
11. The display device according to claim 1 , wherein:
the semiconductor light emitting devices are blue light emitting devices; and
the wavelength converting layer is a yellow wavelength converting layer.
12. The display device according to claim 11 , further comprising a color filter comprising red, green, and blue color filters repeatedly aligned and disposed on the yellow wavelength converting layer.
13. The display device according to claim 1 , wherein:
the semiconductor light emitting devices are blue light emitting devices; and
the wavelength converting layer comprises a red fluorescent (phosphor) material, a green fluorescent (phosphor) material, and a yellow fluorescent (phosphor) material constituting individual pixels.
14. The display device according to claim 1 , wherein the wavelength converting layer further comprises a black matrix disposed between the fluorescent (phosphor) materials.
15. The display device according to claim 1 , wherein red, green, and blue sub-pixels constitute one pixel, or red, green, blue, and white sub-pixels constitute one pixel.
16. A display device using a semiconductor light emitting device comprising:
a substrate;
a plurality of first electrodes disposed on the substrate;
a light emitting device array comprising a plurality of semiconductor light emitting devices electrically connected to the first electrodes and constituting individual pixels;
a plurality of second electrodes electrically connected to the semiconductor light emitting devices; and
a wavelength converting layer disposed on the semiconductor light emitting devices,
wherein the second electrodes and the semiconductor light emitting devices are electrically connected to each other via connection electrodes protruding from the second electrodes,
wherein a length of one of the connection electrodes is different from a length of another connection electrode, and
wherein a length of the connection electrodes decreases from one side of the current input direction of the first electrode to the other side of the current input direction.
17. The display device according to claim 16 , wherein:
the semiconductor light emitting devices are aligned in plural rows; and
the second electrodes are disposed between the rows of the semiconductor light emitting devices.
18. The display device according to claim 16 , wherein:
a thickness or width of each of the first electrodes increases from one side of a current input direction of each of the first electrodes to the other side of the current input direction.
19. The display device according to claim 16 , wherein:
the semiconductor light emitting devices are blue light emitting devices; and
the wavelength converting layer is a yellow wavelength converting layer.
20. The display device according to claim 19 , further comprising a color filter comprising red, green, and blue color filters repeatedly aligned and disposed on the yellow wavelength converting layer.