Field of view is the angular extent of what can be seen with the eye. Various animals have different visual fields. Predators generally have more forward facing with binocular oriented vision, whereas prey have side facing visual fields with greater range (for defensive vision). Eyes positioned on the sides of the head is common in prey species, and increases an animal’s total field of view, but it’s often at the expense of sharper binocular vision.
A deer’s field of view can reach 280 degrees, a Rabbit’s field of view can be 360 with just a small blind spot for a short distance behind their head, but with limited binocular vision. A cat has a 200 degree field of view, but with an amazing 140 degrees of binocular vision. Nature has evolved and found advantage in many variations.
Human’s have general static view of about 135 to 180 degrees horizontally, with about 120 degrees of binocular vision. Ho ever, with eyeball rotation (about 90 degrees) the field of view extends to 270 degrees. In addition, vertical field of vision for humans is about 50 degrees in the upper visual field and 70 degrees in the lower visual field.
Peripheral vision is a part of vision that occurs outside the very center of gaze. There is a broad set of non-central points in the visual field that is included in the notion of peripheral vision.
In addition field of view is, in a way, limited by the fovea, the part of human eye responsible for sharp central vision (the only part of the retina that permits 100% visual acuity), which is only about two degrees of field. Our wide, 120 degree field of view for binocular vision is the basis for stereopsis and is important for depth perception, he remaining peripheral 60–70 degrees does not provide binocular vision.
Web Development Application
Currently the applying knowledge of field of view for Web development is only of minimal importance, understanding the limits of a foveal view is more important. But as our use and understanding of virtual technology increases, it will doubtless require a significant understanding of field of view.