The Effects Of Correlated Color Temperature And Illuminance On Color Discrimination

The effects of both illuminance and correlated color temperature (CCT) on people's (aged 20-25) performance of color discrimination were investigated. FM 100-hue test was used as a task under the combined conditions with 3 CCTs( 3000K, 6500K and 8000K) and 3 illuminance levels (101x, 1001x, 10001x). The results showed that people's performance of color discrimination improved with increasing illuminance, as well as increasing CCT. It was also proved that color rendering index (CRI) of the light sources cannot reflect the effect of spectral power distribution (SPD) on color discrimination. At low illuminance(101x), CCT had significant effects on people's performance and preference, that is, the performance increased with increased CCT, though preference decreased. The study appeals for a complete consideration in lighting design for the effects of both illuminance and CCT, and people's need for performance and preference, especially meaningful for a field with low light levels, such as cockpit, military working places, etc.