Display apparatus and light source device thereof with optical dome
According to the disclosure, a display apparatus includes a printed circuit board (PCB), a light emitting diode (LED) chip mounted on the PCB and configured to emit light, an optical dome formed to enclose the LED chip by being dispensed on the LED chip, and a liquid crystal panel configured to block or pass light output from the LED chip, wherein the optical dome may be formed to satisfy 1.70<r1/r0<1.83 where r0 is a straight distance for light vertically emitted from the LED chip to reach a surface of the optical dome and r1 is a straight distance for maximum output light emitted from the LED chip to reach the surface of the optical dome.
1. A display apparatus comprising:
a printed circuit board (PCB) having a mounting surface,
a light emitting diode (LED) chip mounted on the mounting surface, the LED chip having an optical profile that a larger amount of light is emitted from the LED chip in a lateral direction than in a vertical direction, and
an optical dome covering the LED chip and a portion of the mounting surface adjacent to the LED chip, and
wherein the optical dome satisfies 1.70<r1/r0<1.83, where r0 is a straight distance for light vertically emitted from the LED chip to reach a surface of the optical dome and r1 is a straight distance for maximum output light emitted from the LED chip to reach the surface of the optical dome.
2. The display apparatus of claim 1 , wherein the maximum output light is emitted at an angle at which an optical profile of the LED chip has a largest output.
3. The display apparatus of claim 1 , wherein the LED chip comprises:
an n-type semiconductor layer;
a p-type semiconductor layer; and
a light-emitting layer provided between the n-type semiconductor layer and the p-type semiconductor layer and configured to emit light.
4. The display apparatus of claim 3 , wherein r0 is the straight distance for light vertically emitted from a center of the light-emitting layer to reach the surface of the optical dome, and
wherein r1 is the straight distance for maximum output light emitted from the center of the light-emitting layer to reach the surface of the optical dome.
5. The display apparatus of claim 3 , wherein the LED chip further comprises:
a growth substrate covering an upper surface of the n-type semiconductor layer or the p-type semiconductor layer,
a distributed Bragg reflector (DBR) layer provided on an upper surface of the growth substrate, and
a metal reflector layer provided on a lower surface of the light-emitting layer.
6. The display apparatus of claim 5 , wherein the metal reflector layer comprises aluminum (Al) or a distributed Bragg reflector (DBR).
7. The display apparatus of claim 1 , further comprising:
a liquid crystal panel configured to at least partly block or pass light output from the LED chip; and
an optical film provided between the LED chip and the liquid crystal panel,
wherein the optical film comprises a quantum dot sheet configured to enhance color reproducibility changing a wavelength of light.
8. The display apparatus of claim 1 , wherein the LED chip is mounted on the mounting surface in a chip on board (COB) method.
9. The display apparatus of claim 1 , wherein the LED chip has a horizontal side and a vertical side, and each of the horizontal side and the vertical side has a length that is less than or equal to 500 μm.
10. The display apparatus of claim 1 , further comprising a reflecting sheet having a through hole provided attached to the PCB, wherein the optical dome to passes through the through hole.
11. The display apparatus according to claim 1 , wherein the surface of the optical dome has a semi-circular shape in at least two vertical cross-sections that are perpendicular to each other.
12. The display apparatus according to claim 1 , wherein the optical dome maintains the optical profile by 1.70<r1/r0<1.83, where r0 is the straight distance for light vertically emitted from the LED chip to reach the surface of the optical dome and r1 is the straight distance for the maximum output light emitted from the LED chip to reach the surface of the optical dome.
13. The display apparatus according to claim 1 , wherein the surface of the optical dome comprises a semi-circular shape in at least two vertical cross-sections that are perpendicular to each other.