cone of vision definition

The cone of vision is the visual region displayed by a drawing that relates to a person’s normal vision without his/her peripheral vision.  In a nutshell, the cone of vision is the area of sight – or the angle of sight.  For example, if a person wanted to see the entire theatre stage, usually a cone of vision is 60 degrees is required, so a person would need to sit far enough back to achieve this degree of vision.