White light emitting device with adapted melatonin secretion

摘要

A light emitting device according to embodiments includes a light emitting diode, emitting light with a peak wavelength of 420 - 445 nm, a first blue phosphor emitting light with a peak wavelength of 485 - 530 nm, a second green phosphor emitting light with a peak wavelength of 530-580 nm, and a third red phosphor emitting light with a peak wavelength of 600 - 650 nm. The device emits light having an emission spectrum that has a local minimum value of light intensity between a wavelength of 450 - 470 nm to reduce altered melatonin secretion. The local minimum value being 60% or less of a maximum value of light intensity at a longer wavelength side from the local minimum value, and the device emits light having a color temperature of 4600 K or higher and 5400 K or less.