LIGHT-EMITTING DIVICE COMPRISING A DOME-SHAPED CERAMIC PHOSPHOR

摘要

Some embodiments provide a light-emitting device comprising: a light-emitting diode 50; a substantially transparent encapsulating material 80 having a refractive index in the range of about 1.3 to about 1.8; a layer 70 of low refractive index material having a refractive index in the range of about 1 to about 1.2; and a translucent ceramic phosphor 60 having a refractive index in the range of about 1.6 to about 2.7, and which is substantially dome-shaped with substantially uniform thickness. Some embodiments provide a light-emitting device comprising: a substrate 90; a light-emitting diode 50 mounted on a surface of the substrate; and a substantially hemispheric cover mounted on the surface of the substrate so as to enclose the light emitting diode; wherein the substantially hemispheric cover comprises an outer layer 60, a middle layer 70, and an inner layer 80 arranged concentrically, with the inner layer being nearest the light-emitting diode and the outer layer being a translucent ceramic phosphor.