By changing its curvature, the eye’s lens causes light rays to converge so that they focus on the retina – a process known as accommodation. You can observe this by dragging the candle along the optic axis. This focusing is only possible beyond a limit called the "punctum proximum" or "near point". Otherwise, the image is formed behind the retina and so is blurre.
The diagram is not drawn to scale!
Click on the different parts of the eye to show the labels.
Click and drag the object along the optic axis.