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PROBLEM TO BE SOLVED : To provide a red fluorophor having an intense excitation band in a near-ultraviolet region of near-400 nm wavelength to accomplish the high color rendering and high outputting of a three-wavelength type white LED as a combination of red, green and blue fluorophors with an In-Ga-N-based ultraviolet LED, and also to add a red component to a white LED as a combination of a yellow fluorophor with a blue LED to enable high color rendering and good color tone control as a light source for illumination.
SOLUTION : The red fluorophor comprises a composition represented by the formula : M(LxEu1-x)4(SiyGe1-y)3O13 (wherein, M is an alkaline earth metal atom; L is a rare earth metal atom; and 0≤x≤1 and 0≤y≤1) with the Eu3+ ion as the emission center, being e.g. CaEu4Si3O13 or CaEu(Al0.7Ga0.3)3O7. This fluorophor has excitation peaks near 395 nm and 465 nm wavelengths, being an Eu self-activation type red fluorophor with an emission peak near 615 wavelength, exhibiting red-color emission under excitation by an In-Ga-N-based ultraviolet LED and a blue LED, thus accomplishing the high outputting of a three-wavelength type white LED and the high color rendering of a conventional-type white LED.