contrastu

Contrastu is a term used in design, photography, and vision science to describe the degree to which two or more visual elements differ in luminance, color, texture, or pattern. The concept underpins perceptual separation, visual hierarchy, and readability, influencing how viewers detect, distinguish, and interpret information.

In quantitative terms, contrasti can be measured using several established formulas. Michelson contrast, often applied to periodic patterns, is defined as (Imax − Imin)/(Imax + Imin). Weber contrast describes the difference between a target and a uniform background as (Is − Ib)/Ib. These measures help designers predict how elements will appear under different lighting conditions and on various displays.

Applications of contrastu span many fields. In user interface and graphic design, higher contrasti generally improves legibility and guides attention, while excessive contrast can create visual strain. In photography and cinema, contrastu shapes mood and emphasis by balancing light and shadow. Accessibility standards, such as the Web Content Accessibility Guidelines, specify minimum contrast ratios to ensure readable text for people with visual impairment.

Examples include black text on a white page (high contrastu) versus light gray text on an off-white background (low contrastu). In practice, designers adjust contrasti to optimize clarity, emphasis, and accessibility across devices and environments.

Related topics include contrast, color theory, visual ergonomics, and perceptual psychology.