What is the name of the transparent structure situated behind the pupil that assists in focusing images on the retina?

The lens is the transparent structure located behind the pupil that plays a crucial role in focusing light onto the retina. It adjusts its shape to change the focal distance, allowing for clear vision at varying distances. This process is known as accommodation, which is essential for seeing objects clearly whether they are close or far away. Unlike the cornea, which provides most of the eye's total optical power, the lens fine-tunes the focus. The iris, on the other hand, is responsible for controlling the size of the pupil and thus the amount of light entering the eye, while the retina is the light-sensitive layer at the back of the eye where images are formed but does not take part in the focusing process.