Watch Dr Chauhan explaining how the eye works
Eyes are the organs of vision. They detect light and convert it into electro-chemical impulses in nerves. The eye is a complex optical system that collects light from the surrounding environment, controls the amount of light entering it through a diaphragm (iris) and focuses it through the cornea and lens to form an image. This image is converted into a set of electrical signals in the retina and these are transmitted to the brain through the optic nerves and pathways to the areas of the brain that process vision.
Strictly speaking, it is the brain that ‘sees’ and the eyes merely capture the images.