Definition
In the context of night vision, resolution is the eye's ability to distinguish fine detail and separate small or closely spaced objects as distinct from one another. Visual resolution decreases significantly at night because the rod cells used in low-light vision cannot perceive detail as sharply as the cone cells used in daylight.
Plain English
How clearly your eyes can see small details and tell two close-together objects apart. At night, this ability drops off — things look fuzzier and harder to pick out.
Context Anchor
Seen in night vision discussions about how well a pilot can identify objects, terrain, lights, and other aircraft in low light.
Derivation
From the Latin resolvere, meaning 'to loosen' or 'to separate into parts.' In vision, it refers to the eye's power to separate one detail from another rather than seeing them blurred together.
Why Pilots Care
At night, reduced resolution makes it harder to spot terrain, traffic, runway features, and obstacles. Pilots compensate by using off-center viewing, scanning techniques, and giving the eyes time to adapt to darkness.
Grounding Statement
On a dark night, two lights that are very close together may look like one light until your eyes have enough detail to separate them.
Intuition Check
Resolution here does not mean solving a problem or making a decision. It means the sharpness of what your eyes can separate and identify.
Example Sentence 1
Because visual resolution drops at night, the pilot scanned slowly across the horizon rather than relying on a quick glance.
Example Sentence 2
The pilot noted reduced resolution when trying to identify distant runway lights against the dark background.