Final answer:
The cornea and lens of the eye bend light to focus a sharp image on the retina, with the fovea providing the clearest vision. The lens's ability to alter its shape enables clear vision at varying distances, and the optic nerve transmits visual information to the brain.
Step-by-step explanation:
The bending of the light by the cornea and lens focuses a sharp image onto the retina. When light enters the eye, it first goes through the cornea, which acts as the eye's outermost lens. It significantly contributes to the eye's focusing power since the speed of light changes abruptly when it travels from air into the cornea. The lens, which is clear and curved, adjusts its shape to fine-tune the focusing of light rays, allowing us to see both near and distant objects clearly. This capability is due to the lens's flexibility, which is controlled by ciliary fibers, enabling it to change its radius of curvature and hence the focal length. The lens and cornea combined can be approximated as a single thin lens system that focuses light onto the retina, forming a real image.
The retina contains the fovea, the area with the densest concentration of photoreceptor cells, which is responsible for sharp vision. The optic nerve, which is not sensitive to light and thus creates a blind spot, transmits the visual information collected by the retina to the brain, where it is processed to allow us to perceive objects in the visual field.