The lens of the eye refers to the clear, convex structure that is responsible for refracting light and focusing it onto the retina. Some common synonyms for the lens of the eye include "ocular lens," "crystalline lens," and simply "the lens." In addition, some medical terms for the lens of the eye include "phakos" and "phacos." The lens works in conjunction with other components of the eye, such as the cornea and iris, to allow for clear and sharp vision. However, as we age, the lens can become cloudy and lead to vision problems such as cataracts.