A closer look shows that the receptors in the retina are not arranged in a uniform grid. The spatial distribution of the cones and rods is not uniform. At one point, called the "blind spot", there are no receptors at all because this is where the bundled optic nerves enter the retina. Contrarily, there is also an area of particularly high receptor density known as the fovea, which is located at the focal point of the lens. This central area contains a highly concentrated number of cones. However, the density of cones decreases sharply towards the periphery. This is where the rods sit, which are completely absent in the fovea.
In contrast to rod vision, the entire field of vision is not perceived uniformly. The focus of perception is in its centre. However, the edge of the field of view is not completely without influence: if interesting phenomena are perceived there the gaze is involuntarily directed to this point, which is then imaged in the fovea to be perceived more precisely. An important reason for this shift in the direction of gaze is the presence of high luminance levels, in addition to movements that occur and noticeable colours or patterns, – people's gaze and attention can therefore be
directed by light.
The photosensitive ganglion cells are distributed across the entire retina. However, these receptors react particularly sensitively in the lower area and towards the nose.
