A light emitting device which is able to suppress power consumption while
a balance of white light is maintained is provided. According to the
present invention, either the potential level of the Hi video signal or
Lo video signal which is given to a gate electrode of a transistor, and
the potential level of the power source lines are changed by the
respective corresponding colors. Concretely, the potential level at the
side of Lo and the potential level of the power source line are made to
be changed by the respective corresponding colors when a transistor which
controls current supplied to a light emitting element is a p-channel
type. Conversely, the potential level at the side of the Hi and potential
level of the power source line are made to be changed by the respective
corresponding colors when a transistor which controls current supplied to
a light emitting element is an n-channel type.