A light emitting device that achieves long life, and which is capable of
performing high duty drive, by suppressing initial light emitting element
deterioration is provided. Reverse bias application to an EL element
(109) is performed one row at a time by forming a reverse bias electric
power source line (112) and a reverse bias TFT (108). Reverse bias
application can therefore be performed in synchronous with operations for
write-in of an image signal, light emission, erasure, and the like.
Reverse bias application therefore becomes possible while maintaining a
duty equivalent to that of a conventional driving method.