central region of the fovea which contains no blood vessels in the inner retinal layers
Note 1 to entry: The foveola subtends an angle of about 0,017 rad (1º) in the field of vision.
Note 2 to entry: The central area of the foveola, subtending an angle of about 0,003 rad (0,2º), contains no blue cones.
Note 3 to entry: This entry was numbered 845-02-06 in IEC 60050-845:1987.
Note 4 to entry: This entry was numbered 17-473 in CIE S 017:2011.