The present invention is a fluorescent material characterized by being represented by a composition of the following formula (1) and having a crystal lattice distortion obtained from a Williamson-Hall plot by X-ray diffraction within the range of 0.0005 to 0.0020.
(Sr,Ca,M).sub.3-xMgSi.sub.2O.sub.8:Eu.sub.xformula (1)
wherein M is at least one rare earth metal elements selected from the group consisting of Sc, Y, Gd, Tb and La, and 0.01x0.10. Also, the present invention is a light-emitting device including the fluorescent material, and a light source that emits light by irradiating the fluorescent material with excitation light. Furthermore, the present invention is a method for producing the fluorescent material, including the steps of: obtaining an aqueous slurry of a raw material; and spray-drying the aqueous slurry with hot air at 80 to 300 C.

Embodiments of the invention include a semiconductor light emitting device with a light emitting layer disposed between an n-type region and a p-type region. The light emitting layer emits first light. The device further includes AE.sub.1-xLi.sub.2Be.sub.4O.sub.6:Eu.sub.x, wherein AE=one or more of Sr, Ba, Ca, disposed in the path of the first light. The AE.sub.1-xLi.sub.2Be.sub.4O.sub.6:Eu.sub.x absorbs first light and emits second light. In some embodiments, the first light and second light may be blue.

In a phosphor according to an aspect, an emission site has a perovskite crystal structure expressed by ABX.sub.3, in which A and B are each a cation and X is an anion, and an emission element is located at a B site serving as a body center of the perovskite crystal structure.

Provided is a wavelength conversion member that is less decreased in luminescence intensity with time by irradiation with light of an LED or LD and a light emitting device using the wavelength conversion member. A wavelength conversion member is formed of an inorganic phosphor dispersed in a glass matrix, wherein the glass matrix contains, in % by mole, 30 to 85% SiO.sub.2, 0 to 20% B.sub.2O.sub.3, 0 to 25% Al.sub.2O.sub.3, 0 to 3% Li.sub.2O, 0 to 3% Na.sub.2O, 0 to 3% K.sub.2O, 0 to 3% Li.sub.2O+Na.sub.2O+K.sub.2O, 0 to 35% MgO, 0 to 35% CaO, 0 to 35% SrO, 0 to 35% BaO, 0.1 to 45% MgO+CaO+SrO+BaO, and 0 to 4% ZnO, and the inorganic phosphor is at least one selected from the group consisting of an oxide phosphor, a nitride phosphor, an oxynitride phosphor, a chloride phosphor, an oxychloride phosphor, a halide phosphor, an aluminate phosphor, and a halophosphate phosphor.

A white light emitting device, a light bar and a light apparatus. A relative spectrum of the white light emitting device is (). A relative spectrum of a black body radiation with a corresponding color temperature is S(). An area normalization is performed on () and S() to convert an equal energy spectrum () of the white light emitting device and an equal energy spectrum S() of the black body radiation with the corresponding color temperature. A degree of similarity R of the equal energy spectrum of the white light emitting device and the equal energy spectrum of the black body radiation satisfies the following formula: $R=1-\frac{{}_i^n.Math.S^{}\left(\right)-{}^{}\left(\right).Math.}{{}_i^n{S}^{}\left(\right)},$
when i is 380 nm, n is 680 nm, R85%.

A nitride phosphor having a composition containing Eu, Si, Al, N, and a group 2 element including at least one selected from the group consisting of Mg, Ca, Sr, and Ba. In the composition, a ratio of a total molar content of the group 2 element and Eu to a molar content of Al is 0.8 or more and 1.1 or less, a molar ratio of Eu is 0.002 or more and 0.08 or less, a molar ratio of Si is 0.8 or more and 1.2 or less, and a total molar ratio of Si and Al is 1.8 or more and 2.2 or less. The nitride phosphor has a first peak in a range of 17 2 or more and 19 2 or less and a second peak in a range of 34 2 or more and 35.5 2 or less in a CuK powder X-ray diffraction pattern.

A white light emitting package (20) comprises: a solid-state excitation source (LED 30) for generating excitation light with a dominant wavelength in a range 440 nm to 470 nm; and a layered photoluminescence structure. The layered photoluminescence structure comprises a first photoluminescence layer (32) comprising from 75 wt % to 100 wt % of a manganese-activated fluoride photoluminescence material of the total photoluminescence material content of the first photoluminescence layer, and a second photoluminescence layer (34) comprising photoluminescence material for generating light with a peak emission wavelength in a range from 500 nm to 650 nm. The second photoluminescence layer is disposed on the first photoluminescence layer and the first photoluminescence layer is in closer proximity to the solid-state excitation source than the second photoluminescence layer.

Embodiments of the invention include a semiconductor light emitting device with a light emitting layer disposed between an n-type region and a p-type region. The light emitting layer emits first light. The device further includes AE.sub.1-xLi.sub.2Be.sub.4O.sub.6:Eu.sub.x, wherein AE=one or more of Sr, Ba, Ca, disposed in the path of the first light. The AE.sub.1-xLi.sub.2Be.sub.4O.sub.6:Eu.sub.x absorbs first light and emits second light. In some embodiments, the first light and second light may be blue.

A white light emitting device includes a blue LED chip having a dominant emission wavelength of about 440-465 nm, and a phosphor layer configured to be excited by the dominant emission wavelength of the blue LED chip. The phosphor layer includes a first phosphor having a peak emission wavelength of about 480-519 nm, a second phosphor having a peak emission wavelength of about 520-560 nm, and a third phosphor having a peak emission wavelength of about 620-670 nm. The first phosphor and the second phosphor both have a garnet structure as represented by A.sub.3B.sub.5O.sub.12:Ce, A is selected from the group consisting of Y, Lu, and a combination of thereof, and B is selected from the group consisting of Al, Ga, and a combination of thereof.

A display backlight, comprises: an excitation source, LED (146), for generating blue excitation light (148) with a peak emission wavelength in a wavelength range 445 nm to 465 nm; and a photoluminescence wavelength conversion layer (152). The photoluminescence wavelength conversion layer (152) comprises a mixture of a green-emitting photoluminescence material with a peak emission in a wavelength range 530 nm to 545 nm, a red-emitting photoluminescence material with a peak emission in a wavelength range 600 nm to 650 nm and particles of light scattering material.