Qualities of NASLI light

The Fullspectrum NASLI light has the following qualities:

  • Colour Rendering Index Ra = 91-100 - colours similar to daylight
  • Chromatic temperature Tc = 5500-6500 K - cold daylight similar to afternoon light
  • Circadian Activation Index Ac = 75-115 - effect on the nervous system similar to sunlight

The Qualities of Light

Tcp Correlated Colour Temperature

(Overseas called CCT.) Represents the warm or cold tone (chromaticity) of white light. Defined as the temperature of the body emitting only thermal radiation most similar to the light of the given light source.

Ra General Colour Rendering Index

(Overseas called CRI.) Represents the similarity between ideal and given light. Calculated 100 less as an average of colour shift of eight colour samples (R1…R8).

Ri Special Indices of Colour Rendering

These provide more detailed information on rendering of particular colours. The first eight samples are tints used to calculate Ra. Rendering of saturated colours represent indices R9 to R12. In particular, R9 (deep red) is often poor in mainstream fluorescent lamps with red objects appearing darker and less colourful in such light.

GAI Gamut Area Index

"A Colour Space Coverage Index." Represents the verity of colours regarding their saturation. In Japan, it is often used along Ra. The average of Ra a GAI is one of the best predictions on how people will perceive the verity of colours of a given light source.

Ac Circadian Activation Index

Represents the content of activating blue components in a given light, compared to D65 daylight under the same illuminance. This component of light is responsible for stimulating the brain.