What role do ciliary muscles play in vision?

Ciliary muscles play a crucial role in the process of accommodation, which is the adjustment of the lens's shape to focus light properly onto the retina for clear vision. When viewing objects that are close, the ciliary muscles contract, causing the lens to become more rounded. This increased curvature allows the lens to bend light more sharply for viewing near objects.

Conversely, when looking at distant objects, the ciliary muscles relax, allowing the lens to flatten, which reduces its curvature. This adjustment is essential for maintaining visual clarity at varying distances, making the ciliary muscles integral to the ability to see well both up close and far away. Their direct influence on the lens's shape is the key reason why this answer accurately reflects their role in vision.