Fényerkontraszt

Fényerkontraszt is a term used to describe luminance contrast—the difference in brightness between two adjacent areas of a scene or image. It is a fundamental cue for visual discrimination, helping the eye detect edges, shapes, and texture, and it strongly influences legibility in texts and symbols.

Quantifying luminance contrast commonly relies on established formulas. Michelson contrast, suitable for patterns with alternating bright and dark regions, is defined as CM = (Lmax − Lmin) / (Lmax + Lmin), where Lmax and Lmin are the brightest and darkest luminance values in the local pair. Weber contrast applies when a small target sits on a larger background and is written as CW = (L − Lref) / Lref, with Lref representing the background luminance. Perceived contrast can differ from physical luminance differences due to adaptation level, surrounding context, and spatial frequency.

Perception of fényerkontraszt is influenced by viewing conditions, such as ambient illumination, display gamma, and the observer’s visual state. High luminance contrast can improve edge detection and readability, but excessive contrast may cause glare or fatigue, especially in long viewing tasks.

Applications of luminance contrast include display calibration and optimization, photography and printing workflows, medical and scientific imaging, and ophthalmology research. It is distinct from chromatic (color) contrast, though both contribute to overall visibility and perception. Understanding and controlling fényerkontraszt is essential for designing legible interfaces, effective images, and accurate visual assessments.