LED ILLUMINATION DEVICE WITH LAYERED PHOSPHOR PATTERN

摘要

A method of applying at least two phosphors to an LED (32), wherein a first phosphor material (42) having a lower absorption, shorter luminescence decay time, and/or lower thermal quenching than a second phosphor material (44) is positioned closer to the LED than the second phosphor. Such an arrangement provides a light emitting device (30) with improved lumen output and color stability over a range of drive currents.