LIGHT EMITTING DEVICE AND ILLUMINATOR USING IT

摘要

PROBLEM TO BE SOLVED: To provide a light emitting device, and an illuminator using it, in which variation of color tone is controlled by improving a light emitting device arranged to emit a visible light through combination of an LED and a phosphor.

SOLUTION: A GaN based LED 1 is combined with a phosphor 2 being excited with light L1 emitted from the LED 1 to emit fluorescence (visible light) L2 thus constituting a light emitting device emitting the fluorescence L2. The LED 1 and the phosphor 2 are selected and combined such that variation in the chromaticity of the output light falls within 0.05 on the x-y chromaticity chart when the quantity of driving current being injected into the LED 1 is varied from 0.1 (A/cm2) to 70.0 (A/cm2) per unit emission area. A white lighting fixture in which variation of color tone is controlled can be obtained by employing a high efficiency InGaN based ultraviolet LED as the LED 1 and a white phosphor as the phosphor 2.

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