A light emitting device capable of reducing degradation caused by dispersion
of
impurities such as moisture, oxygen, an alkaline metal, and an alkaline earth metal
is provided. Specifically, a flexible light emitting device with an OLED formed
on a plastic substrate is provided. In a light emitting device using a substrate,
a circular polarizing plate has a single layer or two or more layers of barrier
films formed of a compound or compounds selected from AlNXOY,
AlXNY, and Al2O3, which is (are) capable
of preventing oxygen and moisture from seeping into an organic light emitting layer
of an OLED as well as preventing an alkaline metal, an alkaline earth metal, and
other impurities from penetrating an active layer of a TFT.
