A phosphor in which an element represented by R.sub.δ is solid-solutionized in a phosphor host crystal represented by M.sub.α(L, A).sub.βX.sub.γ, wherein M is at least one type of element selected from Mg, Ca, Sr, Ba and Zn, L is at least one type of element selected from Li, Na and K, A is at least one type of element selected from Al, Ga, B, In, Sc, Y, La and Si, X is at least one type of element selected from O, N, F and Cl (where all of X being N is excluded), R is at least one type of element selected from Mn, Cr, Ti, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho and Yb, α, β, γ and δ satisfy α+β+γ+δ=9, 0.00<α≤1.30, 3.70≤β≤4.30, 3.70≤γ≤4.30, and 0.00<δ≤1.30.

A phosphor powder which is represented by a general formula M.sub.x(Si, Al).sub.2(N, O).sub.3y (where M is Li and one or more alkaline earth metal elements and 0.52x0.9 and 0.06y0.36 are satisfied) and in which a part of M is substituted with a Ce element, in which the phosphor powder includes phosphor particles in which a Si/Al atomic ratio is equal to or more than 1.5 and equal to or less than 6, an O/N atomic ratio is equal to or more than 0 and equal to or less than 0.1, 5 to 50 mol % of M is Li, and 0.5 to 10 mol % of M is Ce, and a diffuse reflectance X1 with respect to light having a wavelength of 700 nm is equal to or more than 88% and equal to or less than 99.9%.

A phosphor in which an element represented by R.sub. is solid-solutionized in a phosphor host crystal represented by M.sub.(L, A).sub.X.sub., wherein M is at least one type of element selected from Mg, Ca, Sr, Ba and Zn, L is at least one type of element selected from Li, Na and K, A is at least one type of element selected from Al, Ga, B, In, Sc, Y, La and Si, X is at least one type of element selected from O, N, F and Cl (where all of X being N is excluded), R is at least one type of element selected from Mn, Cr, Ti, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho and Yb, , , and satisfy +++=9, 0.00<1.30, 3.704.30, 3.704.30, and 0.00<1.30.

The invention provides a lighting unit (100) comprising a light source (10), configured to generate light source light (11) and a luminescent material (20), configured to convert at least part of the light source light (11) into luminescent material light (51), wherein the luminescent material (20) comprises a phosphor (40), wherein this phosphor comprises an alkaline earth aluminum nitride based material having a cubic crystal structure with T5 supertetrahedra, wherein the T5 supertetrahedra comprise at least Al and N, and wherein the alkaline earth aluminum nitride based material further comprises a luminescent lanthanide incorporated therein.

A phosphor is provided, which has a composition of Sr.sub.1-xLiAl.sub.3N.sub.4:Ce.sup.3+.sub.x, wherein 0<x<0.1. Sr.sub.1-xLiAl.sub.3N.sub.4 is a host material, and Ce.sup.3+ is a luminescent center. The phosphor can be collocated with an excitation light source to be applied in an illumination device. On the other hand, the phosphor can be collocated with other phosphors of different colors to be applied in a white light illumination device.

A phosphor is provided, which has a composition of Sr.sub.1-xLiAl.sub.3N.sub.4:Ce.sup.3+.sub.x, wherein 0<x<0.1. Sr.sub.1-xLiAl.sub.3N.sub.4 is a host material, and Ce.sup.3+ is a luminescent center. The phosphor can be collocated with an excitation light source to be applied in an illumination device. On the other hand, the phosphor can be collocated with other phosphors of different colors to be applied in a white light illumination device.

The invention provides a lighting unit (100) comprising a light source (10), configured to generate light source light (11) and a luminescent material (20), configured to convert at least part of the light source light (11) into luminescent material light (51), wherein the luminescent material (20) comprises a phosphor (40), wherein this phosphor comprises an alkaline earth aluminum nitride based material having a cubic crystal structure with T5 supertetrahedra, wherein the T5 supertetrahedra comprise at least Al and N, and wherein the alkaline earth aluminum nitride based material further comprises a luminescent lanthanide incorporated therein.