Field of view

In the context of human and primate vision, the term "field of view" is typically only used in the sense of a restriction to what is visible by external apparatus, like when wearing spectacles[1] or virtual reality goggles.

Note that eye movements are allowed in the definition but do not change the field of view when understood this way.

If the analogy of the eye's retina working as a sensor is drawn upon, the corresponding concept in human (and much of animal vision) is the visual field.

For example, binocular vision, which is the basis for stereopsis and is important for depth perception, covers 114 degrees (horizontally) of the visual field in humans;[7] the remaining peripheral ~50 degrees on each side[6] have no binocular vision (because only one eye can see those parts of the visual field).

Similarly, color vision and the ability to perceive shape and motion vary across the visual field; in humans color vision and form perception are concentrated in the center of the visual field, while motion perception is only slightly reduced in the periphery and thus has a relative advantage there.

As long as the FOV is less than about 10 degrees or so, the following approximation formulas allow one to convert between linear and angular field of view.

Then, using the small-angle approximation: In machine vision the lens focal length and image sensor size sets up the fixed relationship between the field of view and the working distance.

In for example computed tomography, a volume of voxels can be created from such tomograms by merging multiple slices along the scan range.

In remote sensing, the solid angle through which a detector element (a pixel sensor) is sensitive to electromagnetic radiation at any one time, is called instantaneous field of view or IFOV.

A measure of the spatial resolution of a remote sensing imaging system, it is often expressed as dimensions of visible ground area, for some known sensor altitude.

In photography, the field of view is that part of the world that is visible through the camera at a particular position and orientation in space; objects outside the FOV when the picture is taken are not recorded in the photograph.

For a normal lens focused at infinity, the diagonal (or horizontal or vertical) field of view can be calculated as: where

, the FOV is related to the Field Number (FN) by if other magnifying lenses are used in the system (in addition to the objective), the total