Brief description of working of Human Eye

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                        It is part of "Cornea" called "Pupil" which is responsible for focusing light on lens. This light when falls on retina it changes the orientation of the same likely in upside down and from left to right. The nerve signals present on retina after chemical reaction sends these signals to optic nerve which are then passed to "Visual Cortex" of brain where further processing takes place and object is identified in genuine orientation.
                        When light enters "Cornea", there is found considerable change in position of "Object" when seen closing one eye. This difference is usually limited by "Nose". Hence, when object is projected on retina, it is divided into two parts with "Fovia" as the centre which actually is the centre of "Macula".


                           
        Diagram illustrating how ray of light travels via pupil and is processed by brain.



                          This actually creates two parts of retina, namely "Left half" and "Right half".Generally, these parts are referred to as "Nasal Hemiretina" and "Temporal Hemiretina". 
                          In the right eye, "Nasal Hemiretina" from the "Right" side of the eye and "Temporal Hemiretina:" from the left side of the eye together experiences "Right" side view of object whereas "Nasal Hemiretina" from the "Left" side of the eye and "Temporal" Hemiretina from the "Right" side of the eye together experiences the "Left" side view of the object.  Here, most emphasis is kept upon "Object" or "Subject", and hence theory can likely be considered for that "Object" or "Subject" because of minimal attention which we experience to the surrounding. (Where focusing is considered as "Macular Vision". )
                           When "Object" or "Subject" is focused on retina, neural signals processed on retina travel via the axons of the "Ganglion Cells" through the optic nerves and crosses each other constituting a structure which is referred to as "Optic Chiasm". These axons then travel via optic tract to the "Lateral Geniculate Nuclues" , from where they reach to "Primary Visual Cortex", where further processing take place and "Object" or "Subject" is identified with its own genuineness. 






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