The human eye is delicate tissue and arguably the most important sensory organ of the human body. It is our window to the world around us and any significant change in vision will affect our portrayal of that world. Therefore it's critical to obtain a baseline of the strength of your vision clinically in order to recognize changes in time.


Vision occurs when light is processed by your eye and interpreted by your brain. Light passes through the cornea (transparent eye surface). It continues through the pupil (the black of your eye, which is a hole). The pupil becomes larger or smaller to control the amount of light that enters the eye. The coloured portion of the eye is called the iris. It is a muscle that controls the pupil size. After light passes through your pupil, it reaches the lens. The lens focuses light on your retina (the back of the eye). The retina converts light energy into a nerve signal that is carried by the optic nerve to the brain (occipital lobe) where it is interpreted.