Phosphor particle group and light emitting apparatus using the same

摘要

Provided is a phosphor particle group of divalent europium-activated oxynitride green light emitting phosphor particles each of which is a β-type SiAlON substantially represented by a general formula: EuaSibAlcOdNe, where 0.005≦a≦0.4, b+c=12, d+e=16, wherein 60% or more of the phosphor particle group is composed of the phosphor particles in which a value obtained by dividing a longer particle diameter by a shorter particle diameter is greater than 1.0 and not greater than 3.0. A high-efficiency and stable light emitting apparatus using a β-type SiAlON, which includes a light converter using the phosphor particle group, and a phosphor particle group therefor are also provided.

主权项

1. A white light emitting apparatus comprising:
a light emitting element of a gallium nitride-based semiconductor emitting primary light having a peak wavelength of 430-480 nm; and a light converter absorbing a part of said primary light to emit secondary light having a wavelength longer than a wavelength of said primary light, said light converter including a phosphor particle group of divalent europium-activated oxynitride green light emitting phosphor which is a β-type SiAlON substantially represented by a general formula:
EuaSibAlcOdNe, where 0.005≦a≦0.2, b+c=12, d+e=16, said phosphor particle group of divalent europium-activated oxynitride green light consisting of a columnar particle in which a value obtained by dividing a longer particle diameter by a shorter particle diameter is greater than 1.0 and not greater than 3.0, and the light converter further comprising phosphor particles of a red light emitting phosphor.