Accommodation

In German, accommodation means adaptation to different distances. By changing the refractive power of the lens, the eye "focuses" on different distances (similar to the camera).

In near accommodation, the refractive power of the lens is increased. This causes the so-called ciliary muscle, which surrounds the lens circularly, to contract, relaxing the zonula fibres and giving the lens a more rounded shape due to its inherent elasticity.

If the ciliary muscle slackens, the zonula fibers are stretched and the lens becomes flatter. Their refractive power decreases to its lowest value and our eyes are adjusted for distant accommodation: In this way distant objects can be seen clearly.

https://de.wikipedia.org/wiki/Akkommodation_(Eye) _{(Wikipedia CC-by-sa-3.0)}