Lysfarge

Lysfarge is a term used in Danish and Norwegian to refer to the color of light emitted by a source or perceived in illumination. It denotes the hue of light, which depends on the spectral power distribution of the source, the observer’s adaptation, and the surrounding environment. In color science, lysfarge is described by hue, saturation (chroma), and brightness, and can be quantified by measurements such as correlated color temperature (CCT) and color rendering index (CRI). The spectral power distribution (SPD) of a lamp determines its lysfarge, while human perception of lysfarge can vary with context, including the viewing surroundings and adaptation to other light sources. Physically, it is represented in color spaces such as the CIE 1931 XYZ or CIE 1976 UCS, and standardized illuminants (for example D65 daylight or incandescent A) serve as reference points for comparisons.

In practice, lysfarge guides lighting design and display technology. Warm lysfarger (low CCT, roughly 2700–3000 K) are often used for residential spaces to evoke softness, while cool lysfarger (roughly 4000–6500 K) suit work environments and technical settings. Displays and lighting products aim for accurate lysfarge rendering and consistent white balance across devices through calibration to standards like sRGB or Rec. 709.

Historically, investigation of light color began with early optics experiments and evolved into modern color science, enabling standardized measurement and communication of lysfarge. See also color temperature, chromaticity, CRI, CIE color spaces, SPD.