Patent ID: 8807776

Claim:
A backlight unit comprising: a plurality of light-emitting devices which are disposed in a plurality of regions on a substrate, wherein the light-emitting devices are controlled with respect to each of the plurality of regions and each of the light-emitting devices comprises a cap and a plurality of light-emitting device chips emitting light having at least two wavelength ranges within the cap, and emits white light by totally reflecting the light having the at least two wavelength ranges and mixing the light having the at least two wavelength ranges within the cap; an image board which has a reference value and analyzes an image signal which is input by an image signal unit by comparing the image signal with the reference value, thereby obtaining position information corresponding to a region having a relatively higher or lower brightness than the reference value; and a control unit which controls a brightness of the light-emitting devices located in the region corresponding to the position information obtained by the image board, wherein light-emitting devices located in a same region are driven together and light-emitting devices located in different regions are separately driven, wherein each of the plurality of light-emitting devices further comprises a base and a plurality of light-emitting device chips disposed on only a periphery of the base, and wherein the plurality of light-emitting device chips disposed on only the periphery of the base include at least two first type light-emitting device chips each having a first wavelength range, at least two second type light-emitting device chips each having a second wave length range and at least two third type light-emitting device chips each having a third wave length.