The Spectral Optimization of a Commercializable Multi-Channel LED Panel With Circadian Impact

Yi Jiau Saw,Chee Pin Tan,Vineetha Kalavally

doi:10.1109/access.2020.3010339

Yi Jiau Saw, Chee Pin Tan + Show 1 more

Open Access

https://doi.org/10.1109/access.2020.3010339

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Abstract

There exists a need for the design of light emitting diode (LED) luminaires which can deliver both visual and non-visual benefits of light to humans. In this work, we introduce an optimization approach based on spectral shaping for a minimalistic and practical design of a circadian-tunable multi-channel luminaire which also outputs white light with high quality and luminous efficacy of radiation (LER). The spectral optimization approach utilizes Multi-objective Genetic Algorithm to maximize circadian tunability, light quality and LER while minimizing the number of channels. Solution sets are constrained using the non-visual quality metric, Melanopic Efficacy of Luminous Radiation (MELR) from the Melanopic Equivalent Daylight Illuminance (MEDI) approach and the more stringent visual quality metric TM-30 in addition to conventional Color Rendering Index (CRI). By matching theoretically optimized LED parameters to commercially available LED parameters for commercialization purposes, we establish the maximum MELR tunability that is achievable with 4 and 5 LED channels and the resulting trade-off in efficacy and light quality. Based on the results and analysis in this work, we detail a spectral optimization approach to propel the field of indoor lighting towards human-centric lighting.

Highlights

In addition to light being an effective regulator of visual perception, it has been established that it regulates the biological clock or the circadian rhythm of humans [1]
The spectral optimization of light emitting diode (LED) channels approach proposed in this study allows a wide range of circadian tunability which satisfies the non-visual design requirements of a tunable luminaire and simultaneously accounts for optimal visual quality using up-to-date metrics for both visual and nonvisual quality
Metrics used to quantify the non-visual effects of light are in accordance with CIE standards and used in conjunction with the figures of merit for vision performance such as the luminous efficacy of radiation (LER), Duv, Color Rendering Index (CRI) and TM-30

Summary

Introduction

In addition to light being an effective regulator of visual perception, it has been established that it regulates the biological clock or the circadian rhythm of humans [1]. Having filtered the solution sets which do not satisfy the K, CRI and Duv constraints, the algorithm runs through the database containing a comprehensive list of commercially available LED parameters from established brands and selects the closest match in terms of wavelength and FWHM of the channels from the optimization output.

Results

Conclusion