värintoistokyvyllä

Värintoistokyvyllä, often translated as color rendering index (CRI), is a measure of a light source's ability to reveal the colors of various objects faithfully compared to an ideal or natural light source. It is particularly important in applications where accurate color perception is crucial, such as photography, interior design, and retail.

The CRI scale ranges from 0 to 100. A CRI of 100 indicates that the light source renders colors identically to a reference source, typically a black-body radiator or daylight, at the same correlated color temperature. As the CRI value decreases, the light source's ability to accurately reproduce colors diminishes. For example, a light source with a CRI of 80 will reproduce colors reasonably well, while a CRI of 90 or above is considered excellent.

The calculation of CRI involves comparing the spectral power distribution of the light source in question to that of the reference source across several standard color samples. Differences in how the two sources illuminate these samples are used to derive the CRI values. Different lighting applications may have different CRI requirements. For instance, art galleries and museums often require light sources with very high CRI values to ensure the true colors of the artworks are displayed. In contrast, general office lighting might have a slightly lower CRI requirement, though still sufficient for most tasks. Understanding CRI helps in selecting lighting that best suits the visual needs of a particular environment.