Range-gated active TV system tradeoffs

Abstract

Range-gated TV cameras used in conjunction with pulsed scene irradiators offer distinct advantages over their passive counterparts for night-time viewing of terrestrial scenes at long range. Besides being independent of natural scene lighting, active TV cameras can be considered for use with very small fields of view without need of the large objective lenses required by passive systems. Since any camera f-number increases with viewfield decrease may be offset by increase in scene irradiation if source and sensor viewfields are matched.