Bottom lighting module

1. A bottom lighting module, comprising:

a printed circuit board (PCB) having a first face, a second face opposing to the first face, and at least one opening through the first face and the second face;

a reflection sheet disposed on the first face and having a plurality of holes, wherein the opening corresponds to of the plurality of holes; and

a plurality of light emitting diodes(LEDs) disposed individually in the respective holes and the opening, wherein the opening has a first trough-wall and a second trough-wall for holding the plurality of LEDs, and each LED has a light-emitting portion and an LED-base having at least two electrodes connected to the second face of the PCB.

2. The bottom lighting module according to claim 1 , further comprising a heat sink disposed under the second face so as to contact the LED-base.

3. The bottom lighting module according to claim 2 , further comprising a first combiner and a second combiner, the first combiner being secured on the second face, the heat sink being sandwiched between the first combiner and the second combiner.

4. The bottom lighting module according to claim 3 , wherein the first combiner is secured on the PCB by embedding or welding.

5. The bottom lighting module according to claim 2 , wherein the LED-base has a periphery portion contacting the second face and supporting the PCB.

6. The bottom lighting module according to claim 2 , wherein a heat-dissipation paste is applied between the heat sink and the LED-base.

7. The bottom lighting module according to claim 1 , opening wherein the PCB comprises at least two sub-PCBs separated from each other by the at least one opening.

8. The bottom lighting module according to claim 1 , wherein the PCB is a single PCB and the at least one opening is formed in the PCB.

9. The bottom lighting module according to claim 1 , wherein the PCB has an island shape, a fin shape or an I-shape.

10. A bottom lighting module, comprising:

a PCB having a first face, a second face opposing to the first face, and at least one opening through the first face and the second face;

a plurality of LEDs disposed in the corresponding opening, wherein the opening has a first trough-wall and a second trough-wall for holding the plurality of LEDs, and each LED has a light-emitting portion and an LED-base having at least two electrodes connected to the second face of the PCB;

a first combiner being secured on the second face of the PCB; a second combiner; and

a heat sink disposed under the second face so as to contact the LED-base and sandwiched between the first combiner and the second combiner.

11. The bottom lighting module according to claim 10 , further comprising a reflection sheet being disposed on the first face and having a plurality of holes, wherein the at least one opening corresponds to at least two of the plurality of holes.

12. The bottom lighting module according to claim 10 , wherein the LED-base has a periphery portion contacting the second face and supporting the PCB.

13. The bottom lighting module according to claim 10 , wherein a heat-dissipation paste is applied between the heat sink and the LED-base.

14. The bottom lighting module according to claim 10 , wherein the PCB comprises at least two sub-PCBs separated from each other by the at least one opening.

15. The bottom lighting module according to claim 10 , wherein the PCB is a single PCB and the at least one opening is formed in the PCB.

16. The bottom lighting module according to claim 10 , wherein the first combiner is secured on the PCB by embedding or welding.

17. The bottom lighting module according to claim 10 , wherein the PCB has an island shape, a fin shape or an I-shape.