Abstract: Embodiments of the present invention provide a phosphor improved in the emission intensity maintenance ratio without impairing the emission intensity and further a light-emitting device employing that phosphor. The phosphor is activated by manganese and has a basic structure comprising at least one element selected from the group consisting of potassium, sodium and calcium; at least one element selected from the group consisting of silicon and titanium; and fluorine. In an IR absorption spectrum of the phosphor, the intensity ratio of the peak in 3570 to 3610 cm?1 to that in 1200 to 1240 cm?1 is 0.1 or less.

Abstract: A red-light emitting phosphor is provided, having a basic composition represented by Ka(Si1-x,Mnx)Fb and also having a particular Raman spectrum, wherein the intensity ratio I1/I0, which is a ratio of (I1) the peak in a Raman shift of 600±10 cm?1 assigned to Mn—F bonds in the crystal to that (I0) in a Raman shift of 650±10 cm?1 assigned to Si—F bonds in the crystal, is 0.09 to 0.22. This phosphor is produced by bringing a silicon source in contact with an aqueous reaction solution containing potassium permanganate and hydrogen fluoride, wherein a molar ratio of hydrogen fluoride to potassium permanganate is 87 to 127.

Abstract: A phosphor comprising: a chemical composition expressed by the following formula (K1-p, Mp)a(Si1-y, Mny)Fb (M is at least one element selected from the group consisting of Na and Ca, and p satisfies 0?p?0.01, a satisfies 1.5?a?2.5, b satisfies 5.5?b?6.5, and y satisfies 0<y?0.1), Wherein the phosphor satisfies I (2,500-3,000)/I (1,200-1,240)<0.04, when I (1,200-1,240) is an intensity of a highest peak in a range of 1,200-1,240 cm?1 and I (2,500-3,000) is an intensity of a highest peak in a range of 2,500-3,000 cm?1 in an infrared spectrum.

Abstract: A phosphor comprising: a chemical composition expressed by the following formula (K1-p, Mp)a(Si1-y, Mny)Fb (M is at least one element selected from the group consisting of Na and Ca, and p satisfies 0?p?0.01, a satisfies 1.5?a?2.5, b satisfies 5.5?b?6.5, and y satisfies 0<y?0.1), Wherein the phosphor satisfies I (2,500-3,000)/I (1,200-1,240)<0.04, when I (1,200-1,240) is an intensity of a highest peak in a range of 1,200-1,240 cm?1 and I (2,500-3,000) is an intensity of a highest peak in a range of 2,500-3,000 cm?1 in an infrared spectrum.

Abstract: Embodiments of the present invention provide a phosphor improved in the emission intensity maintenance ratio without impairing the emission intensity and further a light-emitting device employing that phosphor. The phosphor is activated by manganese and has a basic structure comprising at least one element selected from the group consisting of potassium, sodium and calcium; at least one element selected from the group consisting of silicon and titanium; and fluorine. In an IR absorption spectrum of the phosphor, the intensity ratio of the peak in 3570 to 3610 cm?1 to that in 1200 to 1240 cm?1 is 0.1 or less.

Abstract: A light-emitting device of an embodiment includes a light-emitting element emitting blue excitation light and a first phosphor excited by the blue excitation light and emitting fluorescence. A peak wavelength of the fluorescence is not shorter than 520 nm and shorter than 660 nm and the peak wavelength of the fluorescence shifting in the same direction when a peak wavelength of the blue excitation light shifts. The first phosphor is one of a yellow phosphor emitting yellow fluorescence, a green phosphor emitting green fluorescence, a yellow-green/yellow phosphor emitting yellow-green/yellow fluorescence and a red phosphor emitting red fluorescence.

Abstract: To provide a red-light emitting phosphor having high luminous efficacy, also a light-emitting device, and further a manufacturing method of the phosphor. Disclosed is a red-light emitting phosphor having a basic composition represented by Ka(Si1-x,Mnx)Fb and also having a particular Raman spectrum. In the spectrum, the intensity ratio of the peak in a Raman shift of 600±10 cm?1 assigned to Mn—F bonds in the crystal to that in a Raman shift of 650±10 cm?1 assigned to Si—F bonds in the crystal is 0.09 to 0.22. This phosphor can be produced by bringing a silicon source in contact with a reaction solution containing potassium permanganate and hydrogen fluoride in such amounts that the molar ratio of hydrogen fluoride to potassium permanganate is 87 to 127.

Abstract: A light emitting device according to embodiments includes a light emitting element emitting light with a peak wavelength of 420˜445 nm, a first phosphor emitting light with a peak wavelength of 485˜530 nm, a second phosphor emitting light with a peak wavelength of 530˜580 nm, and a third phosphor emitting light with a peak wavelength of 600˜650 nm. The device emits light having an emission spectrum that has a local minimum value of light intensity between a wavelength of 450˜470 nm or less, the local minimum value being 60% or less of a maximum value of light intensity at a longer wavelength side from the local minimum value, and the device emits light having a color temperature of 4600 K or higher and 5400 K or less.

Abstract: A light emitting device of an embodiment includes a light emitting element emitting near-ultraviolet light or blue light as exciting light; and a yellow color conversion layer including a yellow phosphor and a resin, the yellow phosphor represented by formula (1) and being capable of converting the exciting light to yellow light, the resin surrounding the yellow phosphor, the yellow color conversion layer containing the yellow phosphor at a volume concentration of at most 7%, the yellow color conversion layer having a region whose cross section parallel to a light emitting surface of the light emitting element has an area larger than the light emitting surface, (Sr1-x1Cex1)a1AlSib1Oc1Nd1 ??(1) wherein x1, a1, b1, c1, and d1 satisfy following relations: 0<x1?0.1, 0.6<a1<0.95, 2.0<b1<3.9, 0<c1<0.45, and 4.0<d1<5.0.

Abstract: The embodiment of the present disclosure provides a phosphor exhibiting an emission peak in the wavelength range of 565 to 600 nm under excitation by light having a peak in the wavelength range of 250 to 500 nm. The emission peak has a half width of 115 to 180 nm inclusive. This phosphor has a crystal structure of Sr2Si7Al3ON13, and is activated by cerium.

Abstract: The embodiment of the present disclosure provides a yellow light-emitting phosphor represented by the formula (1): ((SrpM1-p)1-xCex)2yAlzSi10-zOuNw. In the formula, M is at least one of the alkaline earth metals, and p, x, y, z, u and w are numbers satisfying the conditions of 0?p?1, 0<x?1, 0.8?y?1.1, 2?z?3.5, 0<u?1, 1.8?z?u and 13?u+w?15. The emission peak of the phosphor shifts within a range of less than 15 nm when the peak of exciting light is changed in the range of 350 to 475 nm.

Abstract: A light emitting device according to embodiments includes a light emitting element emitting light with a peak wavelength of 420˜445 nm, a first phosphor emitting light with a peak wavelength of 485˜530 nm, a second phosphor emitting light with a peak wavelength of 530˜580 nm, and a third phosphor emitting light with a peak wavelength of 600˜650 nm. The device emits light having an emission spectrum that has a local minimum value of light intensity between a wavelength of 450˜470 nm or less, the local minimum value being 60% or less of a maximum value of light intensity at a longer wavelength side from the local minimum value, and the device emits light having a color temperature of 4600 K or higher and 5400 K or less.

Abstract: According to one embodiment, the luminescent material shows a luminescence peak in a wavelength range of 570 to 670 nm when excited with light having an emission peak in a wavelength range of 250 to 520 nm. The luminescent material includes a host material having a crystal structure substantially same as the crystal structure of Sr2Si7Al3ON13. The host material is activated by Eu, and includes Sr and Ca to satisfy a relationship of 0.008?MCa/(MSr+MCa)?0.114, where MCa is a number of moles of Ca and MSr is a number of moles of Sr.

Abstract: A light emitting device according to one embodiment includes a board; a light emitting element mounted on the board, emitting light having a wavelength of 250 nm to 500 nm; a red fluorescent layer formed on the element, including a red phosphor expressed by equation (1), having a semicircular shape with a diameter r; (M1?x1Eux1)aSibAlOcNd??(1) (In the equation (1), M is an element that is selected from IA group elements, IIA group elements, IIIA group elements, IIIB group elements except Al (Aliminum), rare-earth elements, and IVB group elements), an intermediate layer formed on the red fluorescent layer, being made of transparent resin, having a semicircular shape with a diameter D; and a green fluorescent layer formed on the intermediate layer, including a green phosphor, having a semicircular shape. A relationship between the diameter r and the diameter D satisfies equation (2): 2.0r(?m)?D?(r+1000)(?m).

Abstract: A white light emitting device includes a light emitting element having a peak wavelength at from 430 nm to 460 nm; and a fluorescent layer on the light emitting element containing a red fluorescent material and a green-yellow fluorescent material. The white light emitting device achieves high color rendering properties, a high average color rendering index Ra and a high luminescent efficiency, or a high white efficiency.

Abstract: The present embodiments provide a yellow light-emitting fluorescent substance of high luminous efficiency and also a production method thereof. This substance is represented by the formula (1): (M1-xREx)2yAlzSi10-zOuNw ??(1) (in the formula, M is at least one element selected from the group consisting of Ba, Sr, Ca, Mg, Li, Na and K), and emits luminescence with a peak within 500 to 600 nm when excited by light of 250 to 500 nm. In the emission spectrum of the substance, the emission band with the above peak has a half-width corresponding to an energy difference of 0.457 eV or less. The substance can be obtained by pulverizing a material mixture so that the D90 value may be 5 ?m or less and then by firing the pulverized mixture.

Abstract: The embodiment of the present disclosure provides a phosphor having such high luminous efficiency as to be capable of realizing a light-emitting device suffering less from color drift even when working with high power. This phosphor is a Ce-activated phosphor having a crystal structure of Sr2Si7Al3ON13, and emitting luminescence with a peak wavelength of 500 to 600 nm under excitation by light with a peak wavelength of 250 to 500 nm. The XRD profile of the phosphor measured with Cu—K? line radiation according to Bragg-Brendano method shows diffraction lines having the intensities I0 and I1 at diffraction angles 2?s in the ranges of 31.55-31.85° and 24.75-250.5°, respectively, on the condition that the ratio of I1/I0 is 0.24 or less.

Abstract: A white light emitting device according to an embodiment includes: a light emitting element having a peak wavelength in a wavelength range of 430 nm or more and 470 nm or less; a first fluorescent material emits light with a first peak wavelength of 525 nm or more and 560 nm or less; a second fluorescent material emits light with a second peak wavelength longer than the first peak wavelength; and a third fluorescent material emits light with a third peak wavelength of 620 nm or more and 750 nm or less, which is longer than the second peak wavelength. The first fluorescent material and the second fluorescent material has a composition of MSi?O?N?, and when the first peak wavelength is denoted by ?1 (nm), whereas the second peak wavelength is denoted by ?2 (nm), 1100??1+?2 and ?2??1?60 are satisfied.

Abstract: A light-emitting device of an embodiment includes a light-emitting element emitting blue excitation light and a first phosphor excited by the blue excitation light and emitting fluorescence. A peak wavelength of the fluorescence is not shorter than 520 nm and shorter than 660 nm and the peak wavelength of the fluorescence shifting in the same direction when a peak wavelength of the blue excitation light shifts. The first phosphor is one of a yellow phosphor emitting yellow fluorescence, a green phosphor emitting green fluorescence, a yellow-green/yellow phosphor emitting yellow-green/yellow fluorescence and a red phosphor emitting red fluorescence.

Abstract: The embodiment provides a process for production of an oxynitride fluorescent substance. An compound containing In or Ga is adopted in the process as a material thereof. The red fluorescent substance produced by the process can be combined with a semiconductor light-emitting element, so as to be used in a light-emitting device or a light-emitting module.