Halophosphate phosphor and white light emitting device

摘要

The present invention provides a blue (blue-green) phosphor that has sufficient emission intensity in the wavelength region around 490 nm and that has high emission luminance at a temperature region reached during LED operation. The present invention also provides a white light-emitting device that uses a high-luminance green phosphor having an emission peak wavelength of 535 nm or greater and that has improved bright blue reproducibility. A phosphor having a chemical composition of general formula [1] has sufficient emission intensity in a wavelength region around 490 nm, and a white light-emitting device that uses such a phosphor has improved bright blue reproducibility. (In general formula [1], X is Cl; c, d and x are numbers satisfying 2.7 ‰¤ c ‰¤ 3.3, 0.9 ‰¤ d ‰¤ 1.1 and 0.3 ‰¤ x ‰¤ 1.2; and a and b satisfy the conditions a+b = 5-x and 0.12 ‰¤ b/(a+b) ‰¤ 0.4.)