Apparent slant of moving targets on T.V. screens

When moving a vertical black and white bar pattern horizontally across a T.V. screen there appears to exist a slant of the pattern depending on movement velocity. Subjects were asked to compensate this geometrical distortion by adjusting a potentiometer. Results show a clear difference between theoretical and actual data where apparent slant of the vertical pattern was always smaller than calculated. Further research work should be done in order to investigate the influence of this effect on the perception of electronically generated and displayed scenes.