A display apparatus, that includes current driving type luminescent
elements, has a driving system that takes the conduction types of TFTs to
control the emission of the luminescent elements into consideration. In
order to reduce driving voltage and improve display quality
simultaneously, the arrangement is provided such that if the second TFT
which performs the "on-off" function of the current for the luminescent
element is of an N channel type, the potential of the common power supply
line ("com") is lowered below the potential of the opposite electrode
("op") of the luminescent element to obtain a higher gate voltage
("Vgcur"). In this case, if the first TFT connected to the gate of the
second TFT is of a P channel type, when using the potential of the
potential-holding electrode ("st") at the "on" state as a reference,
potentials of the scanning signal ("Sgate") at the lower potential and
the common power supply line ("com") are rendered of the same polarities
with respect to this potential of the potential-holding electrode ("st").
Therefore, the potential of the image signal ("data") to turn "on" can be
shifted within the range of the driving voltage in the display apparatus
in the direction to reduce resistances at the "on" states of the first
TFT and the second TFT to reduce driving voltage and improve display
quality.