To provide a bright, high-image-quality image display apparatus, in an
overlap scanning mode in which two scan-wiring lines are selected
simultaneously in each horizontal scanning period, high-frequency
emphasis filtering is performed on a video signal so that a gain at a
spatial frequency corresponding to 1/2 of a vertical critical resolution
is within the range of 0 dB to +6 dB. It is even preferable that a gain
of this high-frequency emphasis filtering at a spatial frequency
corresponding to 7/10 of the vertical critical resolution be higher than
or equal to +3 dB. For example, this high-frequency emphasis filtering
can be implemented by a 3-tap FIR filter having filter coefficients (h1,
h2, h3)=(-x/2, 1+x, -x/2).