Field of view
Short definition
Field of view (FOV) is the angular extent of the image that a virtual reality headset shows at once, measured in degrees.
In plain language
The wider the field of view, the less noticeable the dark frame around the image and the greater the sense of being in the environment tends to be. The field of view of VR headsets is narrower than that of natural human vision. Manufacturers do not always measure it in the same way (horizontal, vertical or diagonal), which makes direct comparisons difficult.