The most commonly used chart for testing the acuity of distant VISION. The chart comprises rows of capital letters, with the letters in each row being smaller than those in the one above. The top line of large letters can be seen by a normally sighted person standing 60 metres away. The subject under test sits 6 metres from the screen and, if he or she can read the 6-metre line of letters, his or her visual acuity is normal at 6/6.