néztávolság

Néztávolság is a term used to describe the maximum distance from which a given observer can clearly discern a target under specified viewing conditions. It is a perceptual measure influenced by factors such as the observer’s visual acuity, the size and contrast of the target, illumination, atmospheric clarity, and potential obstructions in the line of sight. The concept is related to the more common term látótávolság, which is often used in meteorology and road safety to indicate visibility distance under weather conditions.

Determinants of néztávolság include the observer’s eyesight, the physical properties of the target (size, brightness, contrast against the background), and environmental conditions (lighting, fog, rain, dust, haze). The measurement of néztávolság is not fixed; it varies with context and is often expressed for standard conditions or with specific qualifiers such as time of day, weather, and target characteristics. In practice, it can be estimated through geometric reasoning, empirical data, or tests that assess the resolvable detail and visibility thresholds for a given observer group.

Applications of néztávolság appear in fields such as urban planning, road design, signage placement, and architectural layout, where ensuring visibility of important features along lines of sight is essential for safety and functionality. Limitations arise because it depends on subjective human factors and variable conditions, making it a conditional rather than absolute distance.

See also: látótávolság, látásélesség, megfigyelési távolság, látótér. Etymology: néz- meaning “to look” and távolság meaning “distance.”