The Control Method for Wavelength-Based CCT of Natural Light Using Warm/Cool White LED
Keywords:natural light, spectral power distribution, CCT, short wavelength ratio
Reproducing circadian patterns of natural light through lighting requires technology that can control correlated color temperature (CCT) and short wavelength ratio (SWR) simultaneously. This study proposes a method for controlling wavelength-based CCT of natural light using LED light sources. First, the spectral power distribution (SPD) of each channel of the test lighting (two-channel LED lighting with warm white and cool white) is identified through actual measurement. Next, CCT and SWR are calculated based on the additive mixing of SPD using the mixing ratio from the measured SPD. Finally, the regression equations for mixing ratio-CCT and mixing ratio-SWR are derived through regression analysis. These equations are then utilized to implement a wavelength-based CCT control algorithm. For performance and evaluation purposes, natural light reproduction experiments were conducted, achieving a mean error of 94.5K for CCT and 1.5% for SWR.
M. Cole, M. Dejohn, L. McClure, and S. Rogers, “LED Lighting: Minimizing Ecological Impact Without Compromising Human Safety,” IEEE Industry Applications Magazine, vol. 28, no. 6, pp. 49-59, November-December 2022.
A. Menéndez-Velázquez, D. Morales, and A. B. García-Delgado, “Light Pollution and Circadian Misalignment: A Healthy, Blue-Free, White Light-Emitting Diode to Avoid Chronodisruption,” Environmental Research and Public Health, vol. 19, no. 3, article no. 1849, February 2022.
S. R. Pandi-Perumal, D. P. Cardinali, N. F. W. Zaki, R. Karthikeyan, D. W. Spence, R. J. Reiter, et al., “Timing is Everything: Circadian Rhythms and Their Role in the Control of Sleep,” Frontiers in Neuroendocrinology, vol. 66, article no. 100978, July 2022.
Y. S. Kim, S. Y. Kwon, and J. H. Lim, “Implementation of a Natural Light Chromaticity Coordinates-Based Healthy Lighting System,” International Information Institute (Tokyo). Information, vol. 20, no. 2A, pp. 985-992, February 2017.
L. Xi, Z. Chen, M. Chen, J. Zeng, and F. Zhao, “Evaluation of Subjective Feeling on Dynamic Simulated Sunlight,” Current Science, vol. 2, no. 4, pp. 174-181, 2022.
T. Esposito and K. Houser, “Correlated Color Temperature is Not a Suitable Proxy for the Biological Potency of Light,” Scientific Reports, vol. 12, article no. 20223, 2022.
Y. S. Kim, S. Y. Kwon, J. Hwang, and J. H. Lim, “Smartphone-Based Wavelength Control LED Lighting System According to the Sleep-Wake Cycle of Occupants,” Journal of Internet Computing and Services, vol. 17, no. 1, pp. 35-45, 2016. (In Korean)
S. T. Oh and J. H. Lim, “Development and Effect Analysis of Circadian Rhythm-Assisted LED Lighting for Reproducing Short-Wavelength Ratio Characteristics of Natural Light,” International Journal of Electrical Engineering & Education, in press. https://doi.org/10.1177/0020720920988486
E. R. Stothard, A. W. McHill, C. M. Depner, B. R. Birks, T. M. Moehlman, H. K. Ritchie, et al., “Circadian Entrainment to the Natural Light-Dark Cycle across Seasons and the Weekend,” Current Biology, vol. 27, no. 4, pp. 508-513, February 2017.
C. R. C. Moreno, R. Raad, W. D. P. Gusmão, C. S. Luz, V. M. Silva, R. M. Prestes, et al., “Are We Ready to Implement Circadian Hygiene Interventions and Programs?” Environmental Research and Public Health, vol. 19, no. 24, article no. 16772, December 2022.
G. Wyszecki and W. S. Stiles, “Color Science: Concepts and Methods, Quantitative Data and Formulae,” New York: John Wiley & Sons, 2000.
D. Durmus, “Correlated Color Temperature: Use and Limitations,” Lighting Research & Technology, vol. 54, no. 4, pp. 363-375, June 2021.
C. Perdahci and H. Özkan, “LEDs Colours Mixing Using Their SPD and Developing of the Mathematical Model for CCT Calculation,” Light & Engineering, vol. 27, no. 1, pp. 86-96, February 2019.
G. Peruzzi and V. Roberti, “Helmholtz and the Geometry of Color Space: Gestation and Development of Helmholtz’s Line Element,” Archive for History of Exact Sciences, vol. 77, no. 2, pp. 201-220, March 2023.
L. Xu, Q. Ye, and M. R. Luo, “Estimation of the Perceptual Color Gamut on Displays,” Optics Express, vol. 30, no. 24, pp. 43872-43887, November 2022.
C. D. Elvidge, D. M. Keith, B. T. Tuttle, and K. E. Baugh, “Spectral Identification of Lighting Type and Character,” Sensors, vol. 10, no. 4, pp. 3961-3988, April 2010.
F. K. Yam and Z. Hassan, “Innovative Advances in LED Technology,” Microelectronics Journal, vol. 36, no. 2, pp. 129-137, February 2005.
C. Sun, Z. Jin, Y. Song, Y. Chen, D. Xiong, K. Lan, et al., “LED-Based Solar Simulator for Terrestrial Solar Spectra and Orientations,” Solar Energy, vol. 233, pp. 96-110, February 2022.
M. A. St Hilaire, M. L. Ámundadóttir, S. A. Rahman, S. M. W. Rajaratnam, M. Rüger, G. C. Brainard, et al., “The Spectral Sensitivity of Human Circadian Phase Resetting and Melatonin Suppression to Light Changes Dynamically with Light Duration,” Proceedings of the National Academy of Sciences, vol. 119, no. 51, article no. e2205301119, 2022.
C. B. Swope, S. Rong, C. Campanella, R. Vaicekonyte, A. J. Phillips, S. W. Cain, et al., “Factors Associated with Variability in the Melatonin Suppression Response to Light: A Narrative Review,” Chronobiology International, vol. 40, no. 4, pp. 542-556, 2023.
J. Nie, Z. Chen, F. Jiao, Y. Chen, Z. Pan, C. Deng, et al., “α-Opic Flux Models Based on the Five Fundus Photoreceptors for Prediction of Light-Induced Melatonin Suppression,” Building and Environment, vol. 226, article no. 109767, December 2022.
L. Bellia, U. Błaszczak, F. Fragliasso, and L. Gryko, “Matching CIE Illuminants to Measured Spectral Power Distributions: A Method to Evaluate Non-Visual Potential of Daylight in Two European Cities,” Solar Energy, vol. 208, pp. 830-858, September 2020.
A. A. Dowhuszko and B. G. Guzmán, “Closed Form Approximation of the Actual Spectral Power Emission of Commercial Color LEDs for VLC,” Journal of Lightwave Technology, vol. 40, no. 13, pp. 4311-4320, July 2022.
E. Mochizuki and T. Murakumo, “Effects of Chromaticity Difference from Planckian Locus Duv of Lighting on Tinted Color of Illumination and Brightness in Space (Part 1): Experiment Using a Scale Model with Uniform Luminance Distribution,” Japan Architectural Review, vol. 5, no. 4, pp. 507-516, October 2022.
C. S. McCamy, “Correlated Color Temperature as an Explicit Function of Chromaticity Coordinates,” Color Research & Application, vol. 17, no. 2, pp. 142-144, April 1992.
M. C. Catalbas and M. B. Kobav, “Measurement of Correlated Color Temperature from RGB Images by Deep Regression Model,” Measurement, vol. 195, article no. 111053, May 2022.
How to Cite
Copyright (c) 2023 Yang-Soo Kim, Seung-Taek Oh, Jae-Hyun Lim
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Submission of a manuscript implies: that the work described has not been published before that it is not under consideration for publication elsewhere; that if and when the manuscript is accepted for publication. Authors can retain copyright of their article with no restrictions. Also, author can post the final, peer-reviewed manuscript version (postprint) to any repository or website.
Since Oct. 01, 2015, PETI will publish new articles with Creative Commons Attribution Non-Commercial License, under The Creative Commons Attribution Non-Commercial 4.0 International (CC BY-NC 4.0) License.
The Creative Commons Attribution Non-Commercial (CC-BY-NC) License permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes