What change in the eye does accommodation involve?

During accommodation, the shape of the lens in the eye changes to adjust its focal length and bring objects at different distances into clear focus on the retina. The ciliary muscles surrounding the lens contract, causing the lens to become more rounded and increase its curvature. As the lens becomes more convex, its focal length decreases, allowing the eye to focus on nearby objects. When the ciliary muscles relax, the lens returns to its original shape and focal length, shifting the focus back to distant objects. This automatic adjustment in the shape of the lens allows individuals to switch focus effortlessly between objects at different distances.