Research on LED Light Sources Capable of Regulating Circadian Rhythms

Abstract

The model was implemented using the CIE 1931 color matching function, the CIECAM02 color appearance model, and the ANSI/IES TM-30 method. The calculation results indicate that the light source has a CCT of 3903.7 K, Duv=−0.001045, Rf=96.96, Rg=106.40, and mel-DER=0.0880, exhibiting characteristics of medium-low color temperature, extremely high color rendering fidelity, slightly expanded color gamut, and minimal impact on circadian rhythms.

For the daytime lighting scenario, with the objective of maximizing Rf, high-fidelity lighting with an Rf as high as 97.91 was achieved under the constraints of CCT = 6000 ± 500 K and Rg = 95–105. For the nighttime sleep-promoting scenario, with the objective of minimizing mel-DER, we successfully reduced mel-DER to an extremely low level of 0.0043 under the constraints of CCT=3000500 K and Rf≥80, effectively reducing interference with circadian rhythms.

An optimization model was constructed with dual objectives: spectral shape fitting accuracy and consistency of circadian rhythm effect parameters (mel-DER). Experimental results indicate that this method achieved low spectral similarity error (average DTW distance of 0.2270) and circadian effect deviation (average mel-DER error of 0.0126) at most time points, validating that the proposed model can effectively simulate dynamic spectra and reproduce the circadian effects of natural light.

To comprehensively evaluate the impact of different lighting conditions on sleep quality, a multi-criteria evaluation model based on the Entropy-Weighted TOPSIS method was constructed. This model assessed sleep quality across six dimensions—total sleep time (TST), sleep efficiency (SE), sleep latency (SOL), deep sleep percentage (N3%), rapid eye movement (REM) percentage (REM3%), and number of nighttime awakenings. The evaluation scores indicate that Environment C (dim light)>Environment A (sleep-promoting light) > Environment B (standard LED), suggesting that optimized lighting can improve sleep quality to a certain extent.