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.