The present disclosure discloses a blue fluorescent powder for a three primary color warm white LED and a preparation method thereof. SrCO.sub.3, NH.sub.4Cl, H.sub.3BO.sub.3, Eu.sub.2O.sub.3, and NH.sub.4H.sub.2PO.sub.4 function as raw materials to obtain a chemical formula of a blue fluorescent powder Sr.sub.(2-x)Eu.sub.x(BO.sub.3).sub.y(PO.sub.4).sub.(1-y)Cl in a reducing atmosphere by a solid-state sintering method, wherein 0.001x0.1 and 0.001y0.5. The blue fluorescent powder is mixed with CaAlSiN.sub.3:Eu.sup.2+ red fluorescent powder and (SrBa).sub.2SiO.sub.4:Eu.sup.2+ green fluorescent powder at a certain proportion to emit warm white light with a light efficiency and a color rendering index under a violet light excitation. An application prospect is wide.

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.

To provide a semiconductor light emitting device which is capable of accomplishing a broad color reproducibility for an entire image without losing brightness of the entire image. A light source provided on a backlight for a color image display device has a semiconductor light emitting device comprising a solid light emitting device to emit light in a blue or deep blue region or in an ultraviolet region and phosphors, in combination. The phosphors comprise a green emitting phosphor and a red emitting phosphor. The green emitting phosphor and the red emitting phosphor are ones, of which the rate of change of the emission peak intensity at 1000 C to the emission intensity at 25 C., when the wavelength of the excitation light is 400 nm or 455 nm, is at most 40%.

Provided is a method of manufacturing a light emitting device, comprising: preparing a base body having a concave portion; disposing a light emitting element at the bottom of the concave portion; disposing a first resin containing first phosphor particles having an average particle size of 10 m or more and 30 m or less and a first filler having an average particle size of 5 m or more and 20 m or less to cover the light emitting element; centrifugally precipitating the first phosphor particles and the first filler toward the base body; temporarily curing the first resin; disposing a second resin containing second phosphor particles and a second filler having an average particle size of 5 nm or more and 100 nm or less on the first resin temporarily cured; centrifugally precipitating the second phosphor particles and the second filler toward the first resin; and curing the first and second resins.

A light-emitting device includes a light-emitting element with a peak emission wavelength in a range of 400 nm to 410 nm and a fluorescent member that contains a first phosphor with a peak emission wavelength in a range of 440 nm to 470 nm containing a Eu-activated alkaline-earth phosphate that contains Cl in a composition, a second phosphor with a peak emission wavelength in a range of 500 nm to 530 nm containing a Eu-activated halogen-containing alkaline-earth silicate, a third phosphor with a peak emission wavelength in a range of 530 nm to 600 nm containing a Ce-activated rare-earth aluminate, and a fourth phosphor with a peak emission wavelength in a range of 600 nm to 660 nm containing a Eu-activated silicon nitride containing Al and at least one of Sr and Ca in a composition.

An LED pump light with multiple phosphors is described. LEDs emitting radiation at violet and/or ultraviolet wavelengths are used to pump phosphor materials that emit other colors. The LEDs operating in different wavelength ranges are arranged to reduce light re-absorption and improve light output efficiency.

To provide a semiconductor light emitting device which is capable of accomplishing a broad color reproducibility for an entire image without losing brightness of the entire image. A light source provided on a backlight for a color image display device has a semiconductor light emitting device comprising a solid light emitting device to emit light in a blue or deep blue region or in an ultraviolet region and phosphors, in combination. The phosphors comprise a green emitting phosphor and a red emitting phosphor. The green emitting phosphor and the red emitting phosphor are ones, of which the rate of change of the emission peak intensity at 100 C. to the emission intensity at 25 C., when the wavelength of the excitation light is 400 nm or 455 nm, is at most 40%.

A light emitting device includes a light emitting element having a peak emission wavelength of 410 nm to 440 nm and a phosphor member. The phosphor member includes a first phosphor having a peak emission wavelength of 430 nm to 500 nm and containing an alkaline-earth phosphate, a second phosphor having a peak emission wavelength of 440 nm to 550 nm and containing at least one of an alkaline-earth aluminate and a silicate containing Ca, Mg, and Cl, a third phosphor having a peak emission wavelength of 500 nm to 600 nm and containing a rare-earth aluminate, a fourth phosphor having a peak emission wavelength of 610 nm to 650 nm and containing a silicon nitride containing Al and at least one of Sr and Ca, and a fifth phosphor having a peak emission wavelength of 650 nm to 670 nm and containing a fluorogermanate.

A light-emitting device includes a light-emitting element with a peak emission wavelength in a range of 400 nm to 410 nm and a fluorescent member that contains a first phosphor with a peak emission wavelength in a range of 440 nm to 470 nm containing a Eu-activated alkaline-earth phosphate that contains Cl in a composition, a second phosphor with a peak emission wavelength in a range of 500 nm to 530 nm containing a Eu-activated halogen-containing alkaline-earth silicate, a third phosphor with a peak emission wavelength in a range of 530 nm to 600 nm containing a Ce-activated rare-earth aluminate, and a fourth phosphor with a peak emission wavelength in a range of 600 nm to 660 nm containing a Eu-activated silicon nitride containing Al and at least one of Sr and Ca in a composition.

Provided is a method of manufacturing a light emitting device, comprising: preparing a base body having a concave portion; disposing a light emitting element at the bottom of the concave portion; disposing a first resin containing first phosphor particles having an average particle size of 10 m or more and 30 m or less and a first filler having an average particle size of 5 m or more and 20 m or less to cover the light emitting element; centrifugally precipitating the first phosphor particles and the first filler toward the base body; temporarily curing the first resin; disposing a second resin containing second phosphor particles and a second filler having an average particle size of 5 nm or more and 100 nm or less on the first resin temporarily cured; centrifugally precipitating the second phosphor particles and the second filler toward the first resin; and curing the first and second resins.