The science of vision is a very intricate and complicated topic that demands much patience and a comprehensive research for an in-depth understanding of the material. Due to the fact that the make-up of the human eye is so complex it would be nearly impossible for a person to truly understand all of the functionalities concerning the eye without thoroughly studying the topic at hand. Almost like an actual camera, the eyeball receives light through an opening (whereas the light receives camera). It then has a specific lens in order to focus the membrane that is sensitive at the back of the eyeball completely.
A circular and radial muscle within the iris that unwinds and contracts in order to adjust the size of the pupil controls the light that gets to the eyeball itself. Firstly, the light must pass through what is called the cornea, which in simple term is a tissue put in place for protection of the eyeball. Given its flexibility and adjustability the cornea is able to reflect the light in order to centre it towards the retina, which is located at the back of the eyeball. The retina, being covered in thousands, and millions of light-sensitive receptors, which are known as “rods” and “cones”, contain pigment molecules that change shape when hit by light.
These are just the basic functionalities of the eyeball but there is more than can be found and said about this topic, through in-depth research. Information about the eyeball can be found on the Internet but also within textbooks found on amazon or provided by professors. Thehigh index 1.74 can usually be found at the back of most ophthalmology textbooks. In the event that satisfactory information is not found within a textbook one can also look online or better yet, watch documentaries about the eye and site for better understanding.