Abstract: 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>PI(90)/PI(MAX)>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.

Abstract: A headlamp includes a semiconductor laser for emitting laser beams having a bluish purple oscillation wavelength, a light emitting section for emitting light while being irradiated with the laser beams emitted from the semiconductor laser, and a transmission filter for shielding coherent components included in the laser beams whereas transmitting incoherent components included in the laser beams.

Abstract: A headlamp includes (i) a semiconductor laser for emitting laser beams, (ii) a light emitting section that includes a first fluorescent material having a peak of emission spectrum which peak falls within a range from 450 nm to 500 nm, and that emits white fluorescence while being irradiated with exciting light emitted from the semiconductor laser, and (iii) a transmission filter for shielding the laser beams and transmitting the fluorescence emitted from the light emitting section.

Abstract: A JEM phase phosphor having superior luminous efficiency is obtained, and a light emitting device is provided, which includes first and second phosphors and in which fluorescence from the first phosphor is not much absorbed by the second phosphor, with the JEM phase phosphor used as a first phosphor. The first phosphor is the JEM phase phosphor having optical absorption of at most 30% at a wavelength in a relation of complementary color to the emission wavelength of the first phosphor. In the light emitting device having a combination of the first phosphor and the second phosphor emitting fluorescence of longer wavelength than the first phosphor, the first phosphor has optical absorption at the emission wavelength of the second phosphor of at most 30%.

Abstract: The present invention provides an oxynitride phosphor represented by a composition formula M(1)1-jM(2)jSibAlcOdNe (composition formula I) or a composition formula M(1)1-a-jM(2)jCeaSibAlcOdNe (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.

Abstract: The invention provides an oxynitride phosphor represented by a composition formula M1?aCeaSibAlcOdNe, 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?a?1; the b that represents a composition ratio of Si is a real number satisfying b=(6?z)×f; the c that represents a composition ratio of Al is a real number satisfying c=(1+z)×g; the d that represents a composition ratio of O is a real number satisfying d=z×h; the e that represents a composition ratio of N is a real number satisfying e=(10?z)×i; the z is a real number satisfying 0.1?z?3; the f is a real number satisfying 0.7?f?1.3; the g is a real number satisfying 0.7?g?3; the h is a real number satisfying 0.7?h?3; the i is a real number satisfying 0.7?i?1.

Abstract: 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 ?-type Si3N4 crystal structure, an amount of oxygen in the crystals being not higher than 0.8 mass %.

Abstract: The present invention provides an oxynitride phosphor represented by a composition formula M(1)1?jM(2)jSibAlcOdNe (composition formula I) or a composition formula M(1)1?a?jM(2)jCeaSibAlcOdNe (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.

Abstract: The invention provides an oxynitride phosphor represented by a composition formula M1-aCeaSibAlcOdNe, 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?a?1; the b that represents a composition ratio of Si is a real number satisfying b=(6?z)×f; the c that represents a composition ratio of Al is a real number satisfying c=(1+z)×g; the d that represents a composition ratio of O is a real number satisfying d=z×h; the e that represents a composition ratio of N is a real number satisfying e=(10?z)×i; the z is a real number satisfying 0.1?z?3; the f is a real number satisfying 0.7?f?1.3; the g is a real number satisfying 0.7?g?3; the h is a real number satisfying 0.7?h?3; the i is a real number satisfying 0.7?i?1.

Abstract: 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.

Abstract: 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<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.

Abstract: 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<x.ltoreq.1), where each of the layers has a thickness of several molecular layers or less;optical guiding layers consisting of Al.sub.y Ga.sub.1-y As (x.ltoreq.y.ltoreq.1) sandwiching the quantum well region, where the AlAs mole fraction varies continuously; andcladding layers covering the optical guiding layers.

Abstract: 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.

Abstract: A method for the production of semiconductor devices comprising: subjecting a GaAs substrate with an oxidized film thereon to a degasification treatment, heating the substrate during a radiation treatment by a molecular beam within a pre-treatment chamber to remove the oxidized film from the substrate, and growing a phosphorous compound semiconductor layer on the substrate by molecular beam epitaxy within a growth chamber connected to the pre-treatment chamber.

Abstract: A semiconductor laser device comprising a multi-layered semiconductor crystal containing an active region for laser oscillation, wherein the extended portions of said active region which are adjacent to both sides of one facet having the width of a selected value of said device constitute light-absorbing regions by which light in a high-order transverse mode is absorbed to a greater extent than that in a fundamental transverse mode, thereby achieving laser oscillation in a stable fundamental transverse mode up to a high output power.

Abstract: A semiconductor device having a superlattice composed of two kinds of semiconductor materials, wherein the lattice unit of said superlattice is composed of periodically laminated layers consisting of four or more kinds of thin layers which are different from each other in the combination of materials and thickness.

Abstract: A semiconductor laser device comprising a single or a plurality of quantum well regions formed by a superlatticed structure which is composed of alternate layers consisting of thin GaAs layers and thin Al.sub.x Ga.sub.1-x As (0<x<1) layers, each of said layers having a thickness of five molecular layers or less and each of said quantum well regions having a thickness in the range of 100 .ANG. to 150 .ANG..

Abstract: A semiconductor laser device comprising a laser oscillation-operating area containing a first cladding layer, an active layer, an optical guiding layer and a second cladding layer in that order, wherein a striped impurity-diffusion region is formed into said second cladding layer from one facet to the other facet and a plurality of narrow strips of GaAs with a spaced pitch are formed in parallel with both facets in the region, except for the region corresponding to said striped diffusion region, which is positioned at the interface between the optical guiding layer and the second cladding layer.

Abstract: An optical semiconductor device comprising a GaAs substrate and a lamination of molecular layer units formed on said GaAs substrate, said molecular layer units being composed of binary compound semiconductors of InP, GaP and AlP.

Abstract: An active layer for laser oscillation and optical guiding layers for guiding laser light sandwiching the active layer therebetween are included in the device. At least one of the optical guiding layers is formed by a superlattice, the optical refractive index of which is lower than that of the active layer. Further, the optical refractive index is gradually decreased in the direction from the portion of the optical guiding layer adjacent to the active layer, to the outside of the optical guiding layer.