visual acuity, <quantitatively>
visual resolution, <quantitatively>
measure of spatial discrimination such as the reciprocal of the value of the angular separation in minutes of arc of two neighbouring objects (points or lines or other specified stimuli) which the observer can just perceive to be separate
Note 1 to entry: This entry was numbered 17-1403 (2.) and 17-1415 in CIE S 017:2011.