Some basic problems concerning vision test charts, such as size progression and target selection are discussed. It is suggested to use a chart containing on one side different, possibly non-homogeneous, alphabetic letters, on the other side some “gratings” such as the Bessel distributions suggested by Kelly. In this way the classical estimate of visual acuity, complicated by pattern recognition and by multiple discriminations, might be compared to the estimate of the “cut-off” frequency. The difference between these two estimates is expected to depend on the degree of sophistication of the subject. As far as target progression in size is concerned, the use of a constant increment in spatial frequency (say, 3 cpd or 6 cpd) is suggested, according to the linear decay of the transfer function of the visual system. However, this progression does not correspond to the geometrical progression usually recommended.