A method and a device for correcting the phase between the pixel clock of
a graphics card and the sampling clock of a flat-panel display with an
analog interface in a system including a flat-panel display, graphics
card, and computer. Automatic adjustment of the phase is performed
repeatedly. In the process, the rising edge of a video pulse of a
sufficiently bright image spot in the first image column close to the
back-porch region is determined. The falling edge of a video pulse is
determined at a sufficiently bright image spot in the last image column
close to the front-porch region, and the phase is adjusted such that the
sampling instant is situated approximately at the midpoint between the
rising and falling edges of a video pulse.