Lichtness

Lichtness is a term sometimes used in art, design, and philosophy to describe the degree to which a scene or object appears to emit or reflect light, or to the perceptual quality of light in a space. It is not widely standardized and is often treated as a synonym for brightness or luminance in casual usage.

The term appears to be derived from the German Licht (light) with the English -ness suffix, and it has no formal definition in physics.

In perceptual psychology, Lichtness refers to perceived intensity of light in a field, determined by luminance, adaptation, contrast, and glare, and it may differ from objectively measured luminance.

In design and art, Lichtness influences mood, readability, and spatial perception. High Lichtness spaces feel open and energetic; low Lichtness spaces feel intimate or moody. It can be influenced by color temperature and reflectance.

Measurement is not standardized for Lichtness. It is typically approximated by luminance (candela per square meter) and illuminance (lux) and by subjective rating scales; modern photography and architectural lighting use high dynamic range imaging to map perceived Lichtness.

Criticism and usage: Because it overlaps with established terms, guidance often avoids it in formal texts; some sources reserve Lichtness for a phenomenological attribute, separate from objective luminance.

See also: brightness, luminance, illuminance, photometry, color appearance.