Definitions for "Instantaneous field of view"
A term specifically denoting the narrow field of view designed into detectors, particularly scanning radiometer systems, so that, while as much as 120° may be under scan, only radiation from a small area is being recorded at any one instant. (See pixel, field of view).
Measure of spatial resolution of scanning-type sensors. IFOV is an area on the ground "seen" by a sensor.
A measure of the area viewed by a single detector on a scanning system at a given moment in time.