[USNBandit]

Field of view is how much the sensor can see at one time without moving. Field of regard is when you combine the mechanical movement of the sensor with the field of view.

For example, the current generation of night vision goggle has a forty degree field of view, how much you see without moving your head. The field of regard is how much you can see limited by the field of you, plus how far you can move your head.

[Gene Eric]

Thanks!

[andyk]

Great explanation!