Light emitting device and light emitting module having the same
A light emitting device and a light emitting module having the same are provided. A light emitting device includes: a first conductivity type semiconductor layer; a second conductivity type semiconductor layer; and an active layer disposed between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer, in which, upon operation, the active layer emits light of a first peak wavelength and light of a second peak wavelength in which the first peak wavelength may be within a range of about 400 nm to about 415 nm, and the second peak wavelength may be greater than or equal to about 440 nm.
1 . A light emitting device, comprising:
a first conductivity type semiconductor layer;
a second conductivity type semiconductor layer;
an active layer disposed between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer; and
a protection material covering the second conductivity type semiconductor layer, wherein the protection material includes a wavelength conversion material,
wherein:
upon operation, the active layer emits light of a first peak wavelength and light of a second peak wavelength,
the first peak wavelength is less than 500 nm, and
the second peak wavelength is greater than or equal to 500 nm, and
a combination of the first peak wavelength and the second peak wavelength emitted by the active layer causes a radiated light passing through the protection material to include CIE coordinates (x, y) in a range of 0.2<x<0.48, and 0.15<y<0.4.
2 . The light emitting device of claim 1 ,
wherein the first peak wavelength is in a range of 400 nm to 500 nm.
3 . The light emitting device of claim 1 ,
wherein the second peak wavelength is in a range of 500 nm to 600 nm.
4 . The light emitting device of claim 1 ,
wherein a difference between the first peak wavelength and the second peak wavelength is greater than or equal to 30 nm.
5 . The light emitting device of claim 1 ,
wherein an intensity at the first peak wavelength is different from an intensity at the second peak wavelength.
6 . The light emitting device of claim 5 ,
wherein a peak intensity at the first peak wavelength is greater than a peak intensity at the second peak wavelength.
7 . The light emitting device of claim 1 ,
wherein an area of a spectrum of light of the first peak wavelength is different from that of a spectrum of light of the second peak wavelength.
8 . The light emitting device of claim 1 ,
wherein a full width at half maximum of a spectrum of light of the first peak wavelength is different from that of the spectrum of light of the second peak wavelength.
9 . The light emitting device of claim 1 ,
the active layer, comprising:
a lower multi-quantum well structure;
an upper multi-quantum well structure; and
a spacer layer disposed between the lower multi-quantum well structure and the upper multi-quantum well structure.
10 . The light emitting device of claim 9 , wherein:
the lower multi-quantum well structure and the upper multi-quantum well structure include a plurality of grooves, respectively, and
the plurality of grooves of the lower multi-quantum well structure and the plurality of grooves of the upper multi-quantum well structure overlap each other.
11 . The light emitting device of claim 9 , wherein:
the spacer layer is formed of AlGaN or AlInGaN, and
the spacer layer includes a greater Al content than that of a barrier layer in the lower multi-quantum well structure.
12 . The light emitting device of claim 9 , further comprising:
a step coverage layer disposed between the upper multi-quantum well structure and the second conductivity type semiconductor layer,
wherein the step coverage layer is formed of AlGaN or AlInGaN, and
wherein a content of Al in the step coverage layer decreases as a distance from the upper multi-quantum well structure increases.
13 . The light emitting device of claim 1 ,
wherein light of the first peak wavelength and light of the second peak wavelength are simultaneously emitted.
14 . A light emitting module, comprising:
a circuit board;
light emitting devices disposed on the circuit board; and
a protection material covering the light emitting devices and adhering the light emitting devices to the circuit board, wherein the protection material includes a wavelength conversion material and a light diffuser that mixes light emitted from the light emitting devices,
at least one of the light emitting devices, comprising:
a first conductivity type semiconductor layer;
a second conductivity type semiconductor layer; and
an active layer disposed between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer, wherein:
upon operation, the active layer emits light of a first peak wavelength and light of a second peak wavelength,
the first peak wavelength is less than 500 nm, and
the second peak wavelength is greater than or equal to 500 nm, and
a combination of the first peak wavelength and the second peak wavelength emitted by the active layer causes a radiated light passing through the protection material to include CIE coordinates (x, y) in a range of 0.2<x<0.48, and 0.15<y<0.4.
15 . The light emitting module of claim 14 ,
wherein the protection material includes a wavelength conversion material.
16 . The light emitting module of claim 15 , wherein:
the at least one light emitting device has a surface with concave grooves, and
the wavelength conversion material includes a plurality of wavelength conversion materials that are concentrated in the concave grooves.
17 . The light emitting module of claim 14 ,
wherein an intensity of light of the first peak wavelength is greater than that of light of the second peak wavelength.
18 . The light emitting module of claim 14 ,
the active layer, comprising:
a lower multi-quantum well structure;
an upper multi-quantum well structure; and
a spacer layer disposed between the lower multi-quantum well structure and the upper multi-quantum well structure.
19 . The light emitting module of claim 18 , wherein:
the lower multi-quantum well structure and the upper multi-quantum well structure include a plurality of grooves, and
the plurality of grooves of the lower multi-quantum well structure and the plurality of grooves of the upper multi-quantum well structure overlap each other.