the perceived brightness or colour depending on whether the light rays enter the pupil near the centre or the edge. (Sir Walter Stiles (1901-1985), British physicist; Brian H. Crawford, 20th-century British physiologist)
the perceived brightness or colour depending on whether the light rays enter the pupil near the centre or the edge. (Sir Walter Stiles (1901-1985), British physicist; Brian H. Crawford, 20th-century British physiologist)