Abstract: In an optical amplification characteristics simulation apparatus according to the present invention, using spectrums of a signal light input to an optical amplifier and a characteristic parameter for amplification medium, gain wavelength characteristics of the amplification medium are calculated. A calculating formula for the above has a parameter corresponding to a gain fluctuation portion due to a gain spectral hole burning (GSHB) phenomenon, and this parameter is defined by a function obtained by modeling a physical phenomenon in which a population inversion rate is reduced due to the GSHB, based on that electron occupation numbers in each Stark level on the end level side are increased. Then, based on the calculated gain wavelength characteristics, the output power of the signal light is obtained, to thereby perform the optical amplification characteristics simulation on the optical amplifier.

Abstract: In an optical amplification characteristics simulation apparatus according to the present invention, using spectrums of a signal light input to an optical amplifier and a characteristic parameter for amplification medium, gain wavelength characteristics of the amplification medium are calculated. A calculating formula for the above has a parameter corresponding to a gain fluctuation portion due to a gain spectral hole burning (GSHB) phenomenon, and this parameter is defined by a function obtained by modeling a physical phenomenon in which a population inversion rate is reduced due to the GSHB, based on that electron occupation numbers in each Stark level on the end level side are increased. Then, based on the calculated gain wavelength characteristics, the output power of the signal light is obtained, to thereby perform the optical amplification characteristics simulation on the optical amplifier.

Abstract: Phosphor 8 is attached to window portion 6 of housing vessel 7 in light-emitting diode 20. Blue excitation light 9 emitted from blue light-emitting diode chip 4 is irradiated on phosphor 8, and part of excitation light 9 is absorbed by phosphor 8, which converts its wavelength and produces yellow fluorescence 9a to be emitted outward from light-emitting diode 20. In addition, part of excitation light 9 also passes through phosphor 8 and becomes transmitted excitation light 9b, which is then emitted outward from light-emitting diode 20. Yellow fluorescence 9a and blue transmitted excitation light 9b blend to become white light 10.

Abstract: Disclosed is a light-emitting device comprising a semiconductor excitation light source emitting blue-violet light and a solid material illuminant having an absorbent for the blue-violet light containing samarium (Sm). With such a constitution, the light-emitting device has high efficiency, long life and excellent color rendering properties.

Abstract: An optical amplifying glass comprising a matrix glass and, added thereto, from 0.01 to 10 wt % of Er, characterized in that said matrix glass substantially comprises, as represented by mol %, 20 to 80 of Bi2O3, 0 to 74.89 of B2O3, 0 to 79.99 of SiO2, 0.01 to 10 of CeO2, 0 to 50 of Li2O, 0 to 50 of TiO2, 0 to 50 of ZrO2, 0 to 50 of SnO2, 0 to 30 of WO3, 0 to 30 of TeO2, 0 to 30 of Ga2O3 and 0 to 10 of Al2O3, with the proviso that said matrix glass contains at least one of B2O3 and SiO2.

Abstract: An optical amplifier glass comprising a matrix glass containing Bi2O3 and at least one of Al2O3 and Ga2O3, and Er doped to the matrix glass, wherein from 0.01 to 10% by mass percentage of Er is doped to the matrix glass which has a total content of Al2O3 and Ga2O3 of at least 0.1 mol %, a content of Bi2O3 of at least 20 mol %, a refractive index of at least 1.8 at a wavelength of 1.55 &mgr;m, a glass transition temperature of at least 360° C. and an optical basicity of at most 0.49.

Abstract: An optical amplifying glass comprising a matrix glass and from 0.001 to 10% by mass percentage of Tm doped to the matrix glass, wherein the matrix glass contains from 15 to 80 mol % of Bi2O3 and further contains at least one component selected from the group consisting of SiO2, B2O3 and GeO2.

Abstract: An optical amplifying glass comprising a matrix glass and from 0.001 to 10% by mass percentage of Tm doped to the matrix glass, wherein the matrix glass contains from 15 to 80 mol % of Bi2O3 and further contains at least one component selected from the group consisting of SiO2, B2O3 and GeO2.

Abstract: An optical amplifier glass comprising a matrix glass containing Bi2O3 and at least one of Al2O3 and Ga2O3, and Er doped to the matrix glass, wherein from 0.01 to 10% by mass percentage of Er is doped to the matrix glass which has a total content of Al2O3 and Ga2O3 of at least 0.1 mol %, a content of Bi2O3 of at least 20 mol %, a refractive index of at least 1.8 at a wavelength of 1.55 &mgr;m, a glass transition temperature of at least 360° C. and an optical basicity of at most 0.49.