Equivalent Brightness Fitting Calculation Method about White LEDs
White LEDs can show different correlated color temperature (abbreviated as CCT) by adjusting the luminous spectrum peak distribution and relative strength. Recent research results indicate that spectral luminous efficiency function of mesopic vision Vmes(λ) and equivalent brightness are associated with luminous spectra of light sources. A series of white LEDs with different CCT are tested and calculated, it shows white LED with higher CCT has higher mesopic vision equivalent brightness, although the brightness are identical when the tester corrected by traditional photopic vision spectral luminous efficiency V(λ). From the equivalent brightness curve fitting, the curve can be described as a polynomial function, for it excellent correlation, the more value of equivalent brightness could be calculated without complex derivation.
Dongye Sun, Wen-Pei Sung and Ran Chen
Y. Yang et al., "Equivalent Brightness Fitting Calculation Method about White LEDs", Applied Mechanics and Materials, Vols. 121-126, pp. 2721-2725, 2012