2012 Volume 51 Issue 6 Pages 613-621
Nowadays LED lights have been spread rapidly in use for efficiency and life time. However, sometimes LED lights obviously degrade color appearances between different spectral conditions because of the several times bigger spectral color difference than traditional light sources i.e. fluorescent lights. CRI (Color Rendering Index) defined by CIE (Commission Internationale de l'Eclairage) is one of the available means, whereas it is not suitable for nowadays practical color data interchanges between different lighting conditions together with different color reproductions. Quantitative evaluations of light sources and color reproductions are needed urgently to solve the problems. In this study, we introduce a Hyper Spectral Sensor featured with excellent performances for spectral measurements and propose an index to show the quality of color appearances based on the values of CIE L*a*b* uniform color space transferred from the obtained data. The experimental results are confirmed by additional subjective evaluations. It was confirmed that the proposed quantitative evaluations are effective and we also found that it is effective to reduce the problem by minimizing the transitions of spectral distribution of light sources and color reproductions.
