What is the first refracting body of the eye?

The cornea is the first refracting body of the eye due to its unique shape and the curvature it presents to incoming light. It has a more significant refractive index compared to the air outside the eye, allowing it to bend light rays and focus them onto the retina. This process of refraction starts as light enters the eye through the cornea before it passes through the pupil and the crystalline lens.

While the pupil facilitates the amount of light entering the eye, it does not contribute to the refraction of light itself. The iris is responsible for controlling the size of the pupil and indirectly influences the amount of light that reaches the retina. The crystalline lens also plays a crucial role in focusing light, particularly for fine adjustments and clear vision at varying distances, but it follows the cornea in the pathway of light entering the eye. Therefore, the cornea is recognized as the primary refracting surface where the initial bending of light occurs.