Oxynitride fluorescent material and light-emitting device
AssigneeNational Institute for Materials Science
InventorNaoto Hirosaki
Life of this patent
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Abstract
Sialon fluorescent materials with activated Eu or other rare earth ions have been known as fluorescent materials capable of being excited by blue light to emit yellow light. An oxynitride fluorescent material can emit light having a far wider range of wavelengths than ever before, and can be included in a light-emitting device. A fluorescent material contains as a main component a crystal phase having a general formula La3Si8N11O4 or La3Si8−xAlxN11−xO4+x where 0<x≦4, to which an optically active element (M) including one or more elements selected from Mn, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu is added and contained as a luminescence center component.
Claims20
An oxynitride fluorescent material, which contains as a main component a crystal phase represented by a general formula La3Si8N11O4, with an optically active element (M) added thereto as a luminescence center, wherein said optically active element (M) comprises one or more elements selected from Mn, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb and Lu.
An oxynitride fluorescent material, which contains as a main component a crystal phase represented by a general formula La3Si8−xAlxN11−xO4+x, where 0<x≦4, with an optically active element (M) added thereto as a luminescence center.
An oxynitride fluorescent material, which comprises an optically active element (M) and elements La, Si, Al, N and O, wherein M is one or more elements selected from Mn, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb and Lu, has a compositional formula MaLabSicAldNeOf provided that a+b=3, and satisfies all conditions (i) (ii), (iii), (iv) and (v):
- 0.00001≦a≦2.5 (i)
- 4≦c≦10 (ii)
- 0≦d≦4 (iii)
- 7≦e≦14 (iv)
- 2≦f≦8 (v).
Dependencies are inferred from the claim text.