Light emitting device
AssigneeNichia Corporation
InventorsShigeyuki SUZUKI, Hiroyuki WATANABE, Shoji HOSOKAWA
Life of this patent
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Abstract
Provided is a light emitting device which includes a light emitting element having a peak emission wavelength in a range of 400 nm to 500 nm, and a fluorescent member containing a fluorescent material having a peak emission wavelength in a range of 630 nm to 670 nm, and a composition represented by the formula. CasSrtEuuSivAlwNx. In the formula, s, t, u, v, w, and x satisfy 0.25≤s≤0.5, 0.4≤t≤0.75, 0.01≤u≤0.04, 0.8≤s+t+u≤1.1, 0.8≤v≤1.2, 0.8≤w≤1.2, 1.8≤v+w≤2.2, and 2.5≤x≤3.2. The light emitting device emits light having an x value of CIE 1931 chromaticity coordinates of 0.640 or more.
Claims14
A light emitting device comprising:
- a light emitting element having a peak emission wavelength in a range of 400 nm to 500 nm, and
- a fluorescent member containing a fluorescent material having a peak emission wavelength in a range of 630 nm to 670 nm and a composition represented by formula (I):
- CasSrtEuuSivAlwNx (I)
- wherein s, t, u, v, w, and x satisfy 0.25≤s≤0.5, 0.4≤t≤0.75, 0.01≤u≤0.04, 0.8≤s+t+u≤1.1, 0.8≤v≤1.2, 0.8≤w≤1.2, 1.8≤v+w≤2.2, and 2.5≤x≤3.2 and,
- emitting light having an x value of CIE 1931 chromaticity coordinates of 0.640 or more.
A light emitting device comprising:
- a light emitting element having a peak emission wavelength in a range of 400 nm to 500 nm, and
- a fluorescent member containing a fluorescent material having a peak emission wavelength in a range of from 630 nm to 670 nm, and a composition represented by formula (I):
- CasSrtEuuSivAlwNx (I)
- wherein s, t, u, v, w, and x satisfy 0.25≤s≤0.5, 0.4≤t≤0.75, 0.01≤u≤0.04, 0.8≤s+t+u≤1.1, 0.8≤v≤1.2, 0.8≤w≤1.2, 1.8≤v+w≤2.2, and 2.5≤x≤3.2 and,
- emitting light with chromaticity coordinates (x, y) within a chromaticity range defined by an area determined by connecting points (0.500, 0.280), (0.540, 0.340), (0.625, 0.375), (0.735, 0.262), and (0.600, 0.200) with straight lines in a CIE 1931 chromaticity diagram.
Dependencies are inferred from the claim text.