Summary
This paper presents an indirect measurement model for the circadian action factor (CAF) of phosphor-converted white LEDs (PC-WLEDs) as a function of temperature, drive current, and excitation wavelength, enabling LED system designers to assess circadian impact without costly spectrometers. The model offers a practical, low-complexity tool for human-centric lighting design and control of artificial light sources.
Key Findings
- Maximum relative error between indirect CAF measurements and direct calculations does not exceed 2.6%
- Mean relative error does not exceed 0.9%, demonstrating strong consistency of the proposed model
- Spectral power distribution of PC-WLEDs is modeled as an extended Gaussian function of a double-color (blue-yellow) spectrum, capturing the key features relevant to circadian action factor estimation
Categories
The Science of Light: Develops a measurement model for the circadian action factor (CAF) of phosphor-converted white LEDs based on photometric, electrical, and thermal properties, directly addressing quantification of non-visual biological effects of light sources.
Sleep & Circadian Health: The circadian action factor quantified by this model relates to non-visual biological effects relevant to circadian entrainment and melatonin suppression.
Author(s)
X Shen, H Chen, M Xu, X Ji, Q Qin
Publication Year
2024
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