An object of the present invention is to suppress occurrence of vertical streaks and ghosts by realizing complete non-overlap sampling in execution of horizontal driving by a clock drive method. A horizontal driving circuit (17) has a shift register capable of performing a shift operation synchronously with a first clock signal HCK and outputting shift pulses sequentially from respective shift stages thereof; a first switch group for extracting a second clock signal DCK in response to the shift pulses; and a second switch group for sequentially sampling an input video signal in response to the second clock signal DCK extracted by the switches of the first switch group, and supplying the sampled signal to each signal line (12). An external clock generating circuit (18) is provided outside a panel (33) and supplies the second clock signal DCK externally. Further an internal clock generating circuit (19) is formed in the panel (33) and supplies the first clock signal HCK to the horizontal driving circuit (17) in accordance with the second clock signal DCK.