(N/A) The light rays in the visible wavelength focused on the retina through the cornea and lens generate potentials (impulses) in rods and cones.
Photosensitive compounds (photopigments) in the human eyes are composed of opsin (a protein) and retinal (an aldehyde of vitamin $A$).
Light induces the dissociation of the retinal from the opsin,resulting in changes in the structure of opsin. This causes membrane permeability changes. As a result,potential differences are generated in the photoreceptor cells.
This produces a signal that generates action potentials in the ganglion cells through the bipolar cells.
These action potentials (impulses) are transmitted by the optic nerves to the visual cortex area of the brain.
Neural impulses are analyzed,and the image formed on the retina is recognized based on earlier memory and experience.