Current Optics and Photonics

Optical Society of Korea (한국광학회)
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Improving CRI and Scotopic-to-Photopic Ratio Simultaneously by Spectral Combinations of CCT-tunable LED Lighting Composed of Multi-chip LEDs

  • Kim, Jong-Oh (Interdisciplinary Program of LED and Solid-State Lighting Engineering, Pukyong National University) ;
  • Jo, Hyeong-Seob (Interdisciplinary Program of LED and Solid-State Lighting Engineering, Pukyong National University) ;
  • Ryu, Uh-Chan (Interdisciplinary Program of LED and Solid-State Lighting Engineering, Pukyong National University)
  • Received : 2020.03.04
  • Accepted : 2020.04.18
  • Published : 2020.06.25
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Abstract

Important determinants for selecting outdoor lighting are the color-rendering index (CRI) and scotopic-to-photopic (S/P) ratio of the lighting units. The higher the S/P ratio, the better energy savings and visual performance. In this study, CCT-tunable LED lighting units were optimized and fabricated by spectral combination of red, green, blue, and yellow LEDs. The measured results for RGB LEDs provided S/P ratios of 1.55~2.58 and those of RGBY LEDs gave 1.46~2.46 to the correlated color temperatures (CCTs) ranging from 2700 K to 6500 K, with CRI values of over 80 at the same time.

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References

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