Definitions for "Field of View"
The field of view is the width in feet/meters of the area you can see from a distance of 1000 yards/meters away.
the circular field seen when looking into an optical device.
When talking about Multiple Beam Antennas: The beams produced by exciting each port of the BFN individually span the field of view.
The maximum diameter of the reconstructed image.
The solid cone extending out from the detector within which the effective sensitivity of the detector is at least 50 percent of its on-axis, listed, or approved sensitivity.
Maximum cone or fan of rays subtended by the entrance pupil that is transmitted by the instrument to form a usable image.
Essentially the synthesis of the IFOV from the scanning process of the radiometer.
Keywords:  fluorescence