A display device capable of switching over between vertical and horizontal display
on a screen without using a frame memory is provided. A display device has a source
signal line driver circuit (102), a first gate signal line driver circuit
(103), and a second gate signal line driver circuit (104). The scanning
direction of the first gate signal line driver circuit (103) is perpendicular
to the scanning direction of the source signal line driver circuit (102),
and the scanning direction of the second gate signal line driver circuit (104)
is perpendicular to the scanning direction of the first gate signal line driver
circuit (103). During normal display, vertical scanning of the screen is
performed by the first gate signal line driver circuit (103). Images are
displayed in a direction that is in accordance with the scanning direction of the
first gate signal line driver circuit (103). On the other hand, vertical
scanning of the screen is performed by the second gate signal line driver circuit
(104) when switching over between vertical and horizontal display. Images
are displayed in a direction that is in accordance with the scanning direction
of the second gate signal line driver circuit (104).