How does light travel through the eye?

Light travels through the eye by first entering through the cornea, which is the clear outer layer at the front of the eye that helps to focus the light. The cornea provides a significant amount of the eye's total optical power due to its curvature.

After passing through the cornea, light then travels through the pupil, which is the opening in the center of the iris that regulates the amount of light entering the eye. The size of the pupil can change depending on lighting conditions and focus needs, allowing more or less light to pass through.

Next, the light is refracted by the lens. The lens is a transparent structure that further focuses the light onto the retina. The lens can change shape (a process known as accommodation) to focus on objects at various distances.

Finally, the light reaches the retina, which is the light-sensitive layer of tissue lining the back of the eye. The retina contains photoreceptor cells (rods and cones) that convert the light into electrical signals, which are then sent to the brain via the optic nerve for visual processing.

This sequential pathway highlights the importance of each part of the eye in the vision process, illustrating how light is gathered, focused, and converted into signals that the brain can interpret.