Subjective preferences and colour quality metrics of LED light sources

  title={Subjective preferences and colour quality metrics of LED light sources},
  author={Rajendra Dangol and Md Kafiul Islam and M Hyv{\"a}rinen LiSc and Pramod Bhusal and Marjukka Puolakka and Liisa Halonen},
  journal={Lighting Research \& Technology},
  pages={666 - 688}
To understand people's judgement of the naturalness of object colours and preference for the lit environment, lighting booth experiments were conducted. Seven different LED spectral power distributions, all at correlated colour temperatures of 2700 K, 4000 K and 6500 K, were simulated for high CIE colour rendering index (Ra), high colour quality scale (CQS) colour preference scale (Qp) keeping Ra = 80, high feeling of contrast index (FCI) keeping Ra = 80, high CQS relative gamut area scale (Qg… 

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