Accommodation reflex

Changes in contraction of the ciliary muscles alter the focal distance of the eye, causing nearer or farther images to come into focus on the retina; this process is known as accommodation.

[1] The reflex, controlled by the parasympathetic nervous system, involves three responses: pupil constriction, lens accommodation, and convergence.

A near object (for example, a computer screen) subtends a large area in the visual field, i.e. the eyes receive light from wide angles.

The pupil constricts in order to prevent strongly diverging light rays hitting the periphery of the cornea and the lens from entering the eye and creating a blurred image.

[2][3] During the accommodation reflex, the pupil constricts to increase the depth of focus of the eye by blocking the light scattered by the periphery of the cornea.

[6] When the eye focuses on distant objects, the lens holds itself in a flattened shape due to traction from the suspensory ligaments.

Light from a single point of a distant object and light from a single point of a near object being brought to a focus.
The pupil constricts when accommodation is initiated