An active-matrix display device includes rows of gate lines, columns of signal lines, and a matrix of liquid-crystal pixels provided in the region where the gate lines and the signal lines intersect. Vertical scanners sequentially scan each gate line during one vertical period, and select one row of liquid-crystal pixels. A horizontal scanner samples video signal for each signal line, and writes the video signal in the one row of liquid-crystal pixels selected within one horizontal period. A voltage applying means applies to each signal line a voltage equal to or less than the minimum level of the video signal in one horizontal period excluding a time assigned for writing the video signal in one row of liquid-crystal pixels. The repeated application of the voltage during one vertical period approximately equalizes signal leakages from all the pixels, whereby vertical crosstalk can be suppressed.