Sharp Kabushiki Kaisha Corporation

National Institute for Materials Science

National Institute of Advanced Industrial Science and Technology

Phoenix Electric Co., Ltd.

Independent Administrative Institution National Institute for Materials Science

501 Sharp Kabushiki Kaisha

Kohsei Takahashi

Saburo Yamamoto

Toshiro Hayakawa

Takahiro Suyama

Masafumi Kondo

Naoto Hirosaki

Hiroshi Fukunaga

Kenichi Yoshimura

Masamichi Harada

Masatsugu Masuda

Tetsuya Gouda

Takashi Fukuda

Yuta Sakimoto

A light-emitting device including a solid-state light source that emits light having a peak wavelength in the range of 480 nm or less and a fluorescent film that covers the solid-state light source and includes at least one kind of phosphor, wherein the fluorescent film includes at least one kind of near-infrared phosphor that is excited by light from the solid-state light source, has a peak wavelength in the range exceeding 700 nm, and has an emission spectrum with a full width at half maximum of 100 nm or more in a range including the peak wavelength.

Light-emitting device

Provided is a light-emitting device that has a high emission efficiency, excellent stability and temperature properties, and that generates light having a high color rendering property sufficient for practical use. This semiconductor light-emitting device comprises a semiconductor light-emitting element that emits blue light, a green phosphor that absorbs the blue light and emits green light, and an orange phosphor that absorbs the blue light and emits orange light, and is characterized in that the orange phosphor is an Eu-activated &#x3b1;-SiAlON phosphor having an emission spectrum peak wavelength within a range of 595 to 620 nm.

Lighting device with plural fluorescent materials

In a light-emitting device, a 50%-area average diameter of primary particles of a Eu-activated &#x3b2; SiAlON fluorescent material is 10 &#x3bc;m or more, a scattering probability of scattering materials at a peak wavelength of excitation light emitted from an excitation light source is 0.1 mmor more and 0.5 mmor less, and the Eu-activated &#x3b2; SiAlON fluorescent material is entrapped inside a transparent member in a dispersed state together with the scattering materials.

Provided is a light-emitting device that has a high emission efficiency, excellent stability and temperature properties, and that generates light having a high color rendering property sufficient for practical use. This semiconductor light-emitting device () comprises a semiconductor light-emitting element () that emits blue light, a green phosphor () that absorbs the blue light and emits green light, and an orange phosphor () that absorbs the blue light and emits orange light, and is characterized in that the orange phosphor is an Eu-activated &#x3b1;-SiAlON phosphor having an emission spectrum peak wavelength within a range of 595 to 620 nm.

Semiconductor light-emitting device

Provided is a light emitting device with effectively improved color rendering properties. A light emitting deviceincludes: a light sourcethat emits light having the maximum intensity at a predetermined wavelength; a first phosphor (yellow phosphor)that absorbs the light emitted by the light sourceand outputs fluorescent light having the maximum intensity at a first wavelength which is longer than the predetermined wavelength; and a second phosphor (red phosphor)that absorbs the light emitted by the light sourceand outputs fluorescent light having the maximum intensity at a second wavelength which is longer than the first wavelength. An absolute value of wavelength dependency of an optical absorption rate of the second phosphorat the first wavelength is set to not more than 0.6%/nm. Accordingly, the color rendering properties of the light emitted by the light emitting devicecan be effectively improved.

Light emitting device

A method of manufacturing a first phosphor of which emission spectrum shape well matches with a color filter of three primary colors of light, a light-emitting device including the first phosphor, and an image display apparatus including the light-emitting device are provided. The light-emitting device includes a semiconductor light-emitting element emitting excitation light and the first phosphor absorbing the excitation light and emitting green light. The first phosphor contains a solid solution of aluminum element and a metal element M selected from the group consisting of Mn, Ce and Eu in crystals of an oxynitride having a &#x3b2;-type SiNcrystal structure, an amount of oxygen in the crystals being not higher than 0.8 mass %.

Method of manufacturing phosphor, light-emitting device, and image display apparatus

A semiconductor light-emitting device that is high in luminous efficiency and that emits light which is high in color rendering property includes a semiconductor light-emitting element that emits blue light; a green fluorescent substance that absorbs the blue light and emits green light; and an orange fluorescent substance that absorbs the blue light and emits orange light, fluorescence emitted by the green fluorescent substance and the orange fluorescent substance having an emission spectrum that has a peak wavelength of not less than 540 nm and not more than 565 nm and that satisfies the relation of 0.70&#x3e;PI(90)/PI(MAX)&#x3e;0.55, where PI(MAX) represents an emission intensity at the peak wavelength, and PI(90) represents an emission intensity at a wavelength 90 nm longer than the peak wavelength.

There is realized a light-emitting device that emits, with high efficiency, white light with excellent color rendering index. A light-emitting device () of the present invention is a light-emitting device () for emitting white light, including at least a light-emitting element () for emitting blue light, an orange fluorescent material () which absorbs the blue light so as to emit orange light, and a green fluorescent material () which absorbs the blue light so as to emit green light, the orange fluorescent material () being a Ce-activated CaAlSiNfluorescent material in a solid solution crystal form in which Ce and oxygen are dissolved in a crystal having a composition of cCaAlSiN.(1&#x2212;c)LiSiNwhere 0.2&#x2266;c&#x2266;0.8, and the orange fluorescent material () containing 2 weight % or more of Ce.

Disclosed is a light-emitting device that exhibits good color rendering and highly efficiently emits white light in an incandescent bulb color range. The semiconductor light-emitting device () of the present invention includes: a semiconductor light-emitting element () that emits blue light; a green phosphor () that absorbs the blue light and emits green light; and an orange phosphor () that absorbs the blue light and emits orange light. The orange phosphor () produces an emission spectrum having a peak at a wavelength of equal to or greater than 590 nm but equal to or less than 630 nm and having a full width at half maximum of 130 nm or greater at the peak, the full width at half maximum of the emission spectrum of the orange phosphor () being broader than a full width at half maximum of an emission spectrum of the green phosphor (). The orange phosphor () exhibits an absorptance having a peak wavelength of 420 nm or greater. ABS(530) and ABS(MAX) satisfy a relation, ABS(530)/ABS(MAX)&#x3c;0.60, where ABS(MAX) is an absorptance of the orange phosphor () at the peak wavelength thereof, and ABS(530) is an absorptance of the orange phosphor () at a wavelength of 530 nm.

The present invention provides an oxynitride phosphor represented by a composition formula M(1)M(2)SiAlON(composition formula I) or a composition formula M(1)M(2)CeSiAlON(composition formula II) and containing 50% or more of a JEM phase, and a light emitting device including a semiconductor light emitting element emitting an excited light, a first phosphor that is the oxynitride phosphor according to the present invention that absorbs the excited light and emits a fluorescence, and a kind or a plurality of kinds of second phosphor(s) that absorb(s) the excited light and emit(s) a fluorescence having a longer wavelength than the fluorescence emitted by the first phosphor. Thereby, a novel oxynitride phosphor being capable of highly efficiently emitting mainly a light having a wavelength of 510 nm or less and a light emitting device using the same can be provided.

Oxynitride phosphor and light emitting device

The invention provides an oxynitride phosphor represented by a composition formula MCeSiAlON, wherein M denotes La or a compound of which main component is La and sub-component is at least one kind of element selected from the group consisting of Pr, Nd, Sm, Eu, Gd, Th, Dy, Ho, Er, Tm, Yb and Lu; the a that represents a composition ratio of Ce is a real number satisfying 0.1&#x2266;a&#x2266;1; the b that represents a composition ratio of Si is a real number satisfying b=(6&#x2212;z)&#xd7;f; the c that represents a composition ratio of Al is a real number satisfying c=(1+z)&#xd7;g; the d that represents a composition ratio of O is a real number satisfying d=z&#xd7;h; the e that represents a composition ratio of N is a real number satisfying e=(10&#x2212;z)&#xd7;i; the z is a real number satisfying 0.1&#x2266;z&#x2266;3; the f is a real number satisfying 0.7&#x2266;f&#x2266;1.3; the g is a real number satisfying 0.7&#x2266;g&#x2266;3; the h is a real number satisfying 0.7&#x2266;h&#x2266;3; the i is a real number satisfying 0.7&#x2266;i&#x2266;1.3; and a JEM phase is contained in an amount of 50% or more, and a semiconductor light-emitting device that uses the oxynitride phosphor.

Oxynitride phosphor and semiconductor light-emitting device

A double-heterostructure multilayered crystal structure in a semiconductor laser device contains an active layer for laser oscillation. A striped etching-protective thin layer is formed on the double-heterostructure multilayered crystal. A striped-mesa multilayered crystal is formed on the striped etching-protective thin layer. A burying layer is formed on the double-heterostructure multilayered crystal outside of both the striped thin layer and striped-mesa multilayered crystal. This provides refractive index distributions within the active layer corresponding to the inside and the outside of the striped-mesa multilayered crystal. Further, it provides a striped structure which functions as a current path composed of the striped-mesa multilayered crystal.

Semiconductor laser device

In a semiconductor laser device comprising In(Ga.sub.1-x Al.sub.x)P cladding layers and an active region which has one or more In(Ga.sub.1-y Al.sub.y)P (y&lt;x) quantum well layers and which is sandwiched by said cladding layers, superlatticed structures having an altervative lamination of In(Ga.sub.1-x Al.sub.x)P layers and In(Ga.sub.1-y Al.sub.y)P layers are disposed in contact with said cladding layers and/or said quantum well layers.

Quantum well semiconductor laser device

A semiconductor laser device containing a laser oscillation-operating area comprising a superlatticed quantum well region which is composed of layers of GaAs alternating with layers of Al.sub.x Ga.sub.1-x As (0&lt;x.ltoreq.1), where each of the layers has a thickness of several molecular layers or less;

Semiconductor laser device having a graded index waveguide

A semiconductor device is formed by sequentially forming a first clad layer, active layer, second clad layer, and cap layer from, for example, an AlGaAs layer with an AlAs mixing ratio of .gtoreq.0.4, on a substrate made of GaAs or the like by MBE, MOCVD or another high precision growth process. Then AlGaAs layer is selectively removed only in the vicinity of formed ridges, and in this part, grooves on two stripes are formed from the cap layer surface, leaving the second clad layer with an intact thickness of, for example, only 3000 .ANG.. An insulation layer made of, for example, SiN is then formed in the groove area and the AlGaAs layer region, thereby creating a current stripe structure, in which only two grooves provide for current passages, that is, the light-emitting regions. In this structure, the thickness of the mesa pattern (ridge part) between the two grooves may be a minimum limit and the processing precision may be improved, while by properly selecting the thickness of the AlGaAs layer, a sufficiently large distance may be set between the mount surface and the active layer, so that the problem of solder climbing-up along the device end surface may be prevented. When the AlAs mixing ratio is controlled at 0.4 in the AlGaAs layer, it is possible to easily remove portions thereof selectively, by using hydrogen fluoride.

Growing community of inventors

Tenri, Japan

Kohsei Takahashi