Abstract: The present invention provides a white light source comprising a light emitting diode having a light emission peak wavelength of 350 to 490 nm and a phosphor that emits visible light upon excitation by a light emitted from the light emitting diode; wherein, with respect to an arbitrary local maximum value of light-emission intensity between 350 and 780 nm of a light emission spectrum of the white light source, a ratio of a local minimum value of light-emission intensity that is closest on a long wavelength side to the local maximum value is such that, when the local maximum value is taken as 1, the local minimum value is 0.5 or more.

Abstract: The present invention provides a white light source comprising: a blue light emitting diode (blue LED) having a light emission peak wavelength in a range of 421 to 490 nm; and a phosphor layer including phosphor and resin, wherein the white light source satisfies a relational equation of ?0.2?[(P(?)×V(?))/(P(?max1)×V(?max1))?(B?)×V(?))/(B(?max2)×V(?max2))]?+0.2, assuming that: a light emission spectrum of the white light source is P(?); a light emission spectrum of black-body radiation having a same color temperature as that of the white light source is B(?); a spectrum of a spectral luminous efficiency is V(?); a wavelength at which P(?)×V(?) becomes largest is ?max1; and a wavelength at which B(?)×V(?) becomes largest is ?max2, and wherein an amount of chromaticity change on CIE chromaticity diagram from a time of initial lighting up of the white light source to a time after the white light source is continuously lighted up for 6000 hours is less than 0.010.

Abstract: The present invention provides a white light source comprising: a light emitting diode (LED) having a light emission peak wavelength in a range of 350 or more and 420 nm or less; and a phosphor layer including four or more types of phosphors and resin, wherein the white light source satisfies a relational equation of: ?0.2?[(P(?)×V(?))/(P(?max1)×V(?max1))?(B(?)×V(?))/(B(?max2)×V(?max2))]?+0.2, assuming that: a light emission spectrum of the white light source is P(?); a light emission spectrum of black-body radiation having a same color temperature as that of the white light source is B(?); a spectrum of a spectral luminous efficiency is V(?); a wavelength at which P(?)×V(?) becomes largest is ?max1; and a wavelength at which B(?)×V(?) becomes largest is ?max2, and wherein an amount (difference) of chromaticity change on CIE chromaticity diagram from a time of initial lighting up of the white light source to a time after the white light source is continuously lighted up for 6000 hours is less than 0.010.

Abstract: In one embodiment, an LED light bulb includes an LED module, a base part on which the LED module is disposed, and a globe attached to the base part. The LED module includes an ultraviolet to violet light-emitting LED chip mounted on a substrate. A lighting circuit and a bayonet cap are provided at the base part. A phosphor screen emitting white light by absorbing the ultraviolet to violet light emitted from the LED chip is provided on an inner surface of the globe. The phosphor screen has a color in which a* is ?10 or more and +10 or less, b* is 0 (zero) or more and +30 or less, and L* is +40 or more when a body color thereof is represented by an L*a*b* color system.

Abstract: In one embodiment, an aqueous dispersion liquid contains at least one particles selected from tungsten oxide particles and tungsten oxide composite particles. A mean primary particle diameter (D50) of the particles is in the range of 1 nm to 400 nm. In the aqueous dispersion liquid, concentration of the particles is in the range of 0.1 mass % to 40 mass %, and pH is in the range of 1.5 to 6.5. The aqueous dispersion liquid excels in dispersibility of particles and capable of maintaining good liquidity for a long period.

Abstract: A semiconductor light emitting element emits ultraviolet light or blue light that impinges upon a light emitting cover portion including a blue phosphor, a green phosphor, a red phosphor and a deep red phosphor to emit white light by mixing the light emission colors from the phosphors. The deep red phosphor has a main emission peak in a longer wavelength region than a main emission peak of the red phosphor. The red phosphor includes at least one component selected from: a europium-activated SiAlON phosphor and a europium-activated CASN phosphor each having a predetermined composition. The deep red phosphor includes a manganese-activated magnesium florogermanate phosphor having a predetermined composition. The white light emitting lamp is excellent in both high luminance and high color rendering properties.

Abstract: In one embodiment, an aqueous dispersion liquid contains at least one particles selected from tungsten oxide particles and tungsten oxide composite particles. A mean primary particle diameter (D50) of the particles is in the range of 1 nm to 400 nm. In the aqueous dispersion liquid, concentration of the particles is in the range of 0.1 mass % to 40 mass %, and pH is in the range of 1.5 to 6.5. The aqueous dispersion liquid excels in dispersibility of particles and capable of maintaining good liquidity for a long period.

Abstract: The present invention provides a white light source comprising a blue light emitting LED having a light emission peak of 421 to 490 nm and satisfying a relational equation of ?0.2?[(P(?)×V(?))/(P(?max1)×V(?max1))?(B(?)×V(?))/(B(?max2)×V(?max2))]?+0.2, assuming that: a light emission spectrum of the white light source is P(?); a light emission spectrum of black-body radiation having a same color temperature as that of the white light source is B(?); a spectrum of a spectral luminous efficiency is V(?); a wavelength at which P(?)×V(?) becomes largest is ?max1; and a wavelength at which B(?)×V(?) becomes largest is ?max2. According to the above white light source, there can be provided a white light source capable of reproducing the same light emission spectrum as that of natural light.

Abstract: In a embodiment, a white LED for a backlight of a liquid crystal display device conforming to the EBU standard includes an ultraviolet (purple) light-emitting element, and a phosphor layer which contains 1 to 10 wt % of a green phosphor including a divalent europium-activated silicate phosphor, 40 to 80 wt % of a blue phosphor including at least one selected from a divalent europium-activated halo-phosphate phosphor and a divalent europium-activated aluminate phosphor, and 10 to 50 wt % of a red phosphor including at least one selected from a europium-activated lanthanum oxysulfide phosphor and a europium-activated yttrium oxysulfide phosphor.

Abstract: The present invention provides a phosphor comprising a europium-activated sialon crystal having a basic composition represented by the following formula (1) [Formula 1] formula: (Sr1-x, Eux)?Si?Al?O?N???(1) (wherein x is 0<x<1, ? is 0<??4 and ?, ?, ? and ? are numbers such that converted numerical values when ? is 3 satisfy 9<??15, 1???5, 0.5???3 and 10???25), and the sialon crystal includes at least one non-Eu rare earth element selected from Sc, Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu in a proportion of 0.1% by mass or more and 10% by mass or less, and the phosphor emitting green light by being excited by ultraviolet light, violet light or blue light.

Abstract: A white light emitting device includes a blue light emitting diode chip that emits blue light in a specific wavelength band, a first resin layer that seals the blue light emitting diode chip and includes a cured product of silicone resin, and a second resin layer that covers the first resin layer and includes phosphor powder, which absorbs the blue light and emits light in a specific wavelength band, and a cured product of transparent resin. The phosphor powder has a composition represented by the following Formula (1): (Sr1-x-yBaxEuy)2SiO4??(1) (in Formula (1), x and y satisfy a condition that 0.05<x<0.5 and 0.05<y<0.3.) The first resin layer has thickness within a range of 200 ?m to 2000 ?m. The white light emitting device has high luminance for a long period.

Abstract: The present invention provides a white light source satisfying a relational equation of ?0.2?[(P(?)×V(?))/(P(?max1)×V(?max1))?(B(?)×V(?))/(B(?max2)×V(?max2))]?+0.2, assuming that: a light emission spectrum of the white light source is P(?); a light emission spectrum of black-body radiation having a same color temperature as that of the white light source is B(?); a spectrum of a spectral luminous efficiency is V(?); a wavelength at which P(?)×V(?) becomes largest is ?max1; and a wavelength at which B(?)×V(?) becomes largest is ?max2. According to the above white light source, there can be provided a white light source capable of reproducing the same light emission spectrum as that of natural light.

Abstract: The present invention provides a semiconductor light emitting device comprising a light intensity difference reducing layer provided between an ultraviolet semiconductor light emitting element and a wavelength converting material layer, and a backlight and a display device comprising the semiconductor light emitting device. The semiconductor light emitting device is an LED light emitting device which has improved uniformity of emitted light and reduced non-uniformity of brightness and chromaticity of emitted light.

Abstract: An LED light emitting device is provided that has high color rendering properties and is excellent color uniformity and, at the same time, can realize even luminescence unattainable by conventional techniques. A phosphor having a composition represented by formula: (Sr2-X-Y-Z-?BaXMgYMnZEu?)SiO4 wherein x, y, z, and ? are respectively coefficients satisfying 0.1<x<1, 0<y<0.5, 0<z<0.1, y>z, and 0.01<?<0.2 is provided. The phosphor is used in combination with ultraviolet and blue light emitting diodes having a luminescence peak wavelength of 360 to 470 nm to form an LED light emitting device.

Abstract: A white LED lamp including: a conductive portion; a light emitting diode chip mounted on the conductive portion, for emitting a primary light having a peak wavelength of 360 nm to 420 nm; a transparent resin layer including a first hardened transparent resin, for sealing the light emitting diode chip; and a phosphor layer covering the transparent resin layer, the phosphor layer being formed by dispersing a phosphor powder into a second hardened transparent resin, and the phosphor powder receiving the primary light and radiating a secondary light having a wavelength longer than that of the primary light. An energy of the primary light contained in the radiated secondary light is 0.4 mW/lm or less. In the white LED lamp, a backlight, and an illumination device using the white LED lamp an amount of UV light to be contained in the released light and an amount of heat to be generated from the lamp are decreased to be small.

Abstract: A linear white light source 1 includes a base, a plurality of light emitting diode chips linearly disposed on the base and each generating ultraviolet light having a wavelength of not less than 330 nm nor more than 410 nm, and a phosphor layer continuously formed on the base to cover the plurality of light emitting diode chips and containing a red light emitting phosphor, a green light emitting phosphor, and a blue light emitting phosphor.

Abstract: In one embodiment, an LED light bulb includes an LED module, a base portion on which the LED module is disposed, and a glove attached to the base portion. The LED module includes an ultraviolet to violet light-emitting LED chip mounted on a substrate. A lighting circuit and a bayonet cap are provided in and on the base portion. A fluorescent film is provided on an inner surface of the glove, and emits white light by absorbing ultraviolet to violet light emitted from the LED chip. The fluorescent film has a film thickness in a range of 80 to 800 ?m. In the LED light bulb, an amount of ultraviolet light which leaks from the glove is 0.1 mW/nm/lm or less.

Abstract: A white light emitting lamp 1 includes a phosphor layer 5 which emits white light by being excited by light emitted from a semiconductor light emitting element 2. A transparent resin layer 4 is interposed between the semiconductor light emitting element 2 and the phosphor layer 5. The phosphor layer 5 contains, as a green phosphor, a rare earth borate phosphor activated by trivalent cerium and terbium.

Abstract: A positive electrode active material for use in a non-aqueous electrolyte secondary cell comprises a powdery metal oxide (LiCoO2, LiNiO2, LiMn2O4 or the like). When the positive electrode active material is classified with a classification precision index ? of 0.7 or greater so as to obtain a coarse powder having a classification ratio in a range of 0.1% to 5%, a ratio (B/A) of the content (B) of an impurity metal element in the coarse powder obtained by the classification to the content (A) of the impurity metal element in the powder before the classification is 1.5 or less. The contents of the impurity metal elements are compared with respect to Ca, Mn, Fe, Cr, Cu, Zn and the like (exclusive of the metal element constituting the powdery metal oxide). The positive electrode active material for a secondary cell serves to improve cell performance capabilities and production yields.

Abstract: An object of the invention is to provide a photocatalyst material having a higher catalyst effect than conventional photocatalyst materials. The photocatalyst material of the invention contains, as its major component, a tungsten oxide powder excited by a light source which emits light having a wavelength of 430 to 500 nm, the photocatalyst material having a decomposition ability of 50% or more wherein the decomposition ability is given by the following equation based on the following test: [Test for decomposition ability]: 1 g of a tungsten oxide powder and 20 ppm of acetaldehyde (amount A) are poured into a 3-liter glass container, and acetaldehyde (amount B) is measured after light having a peak wavelength of 460 nm±10 nm is irradiated to the mixture for 2 hours to measure the decomposition ability (%): Decomposition ability (%)=[(acetaldehyde amount A?acetaldehyde amount B)/acetaldehyde amount A]×100.