Which part of the eye helps to focus light onto the retina?

The lens is the part of the eye that plays a crucial role in focusing light onto the retina. It is a transparent, flexible structure located behind the iris and the pupil. The primary function of the lens is to change its shape—a process known as accommodation—in order to focus light rays from objects at varying distances sharply onto the retina. When viewing objects up close, the lens becomes thicker and more curved, allowing for a more precise focus of light; conversely, when looking at distant objects, the lens flattens out.

Understanding the role of the lens is critical for vision professionals, as any issues with the lens, such as cataracts or refractive errors, can significantly affect vision quality. This focusing mechanism is essential for clear sight, as it ensures that the light entering the eye is directed correctly so that images are sharp and distinct when they are transmitted to the brain via the retina.