American Board of Ophthalmology (ABO) Practice Exam

The primary function of the lens in the eye is to focus light onto the retina. The lens is a transparent, flexible structure located behind the iris and the pupil. Its ability to change shape, through a process called accommodation, allows it to adjust the focus for objects at varying distances, ensuring that light rays are accurately directed onto the retina. This precise focusing is crucial for creating clear images, which are essential for effective vision.

The lens works in conjunction with the cornea, which also plays a role in refracting light, but the lens's unique ability to alter its curvature enables fine-tuning of focus for different distances. This adaptability is particularly important for activities such as reading or driving, where different focal lengths are required.