Chromaticity-based real-time assessment of melanopic and luminous efficiency of smartphone displays.

We investigate the spectral power distributions of 54 phones (33 measured experimentally in default text mode and 21 downloaded from the web) and estimate the mean ± std. dev. of the luminous efficiency of radiation, melanopic efficiency of radiation, and melanopic/photopic ratio as 287 ± 13 lm/W, 303 ± 26 blm/W, and 1.06 ± 0.13, respectively. We establish the chromaticity-performance characteristics relation to precisely assess the action efficiency of radiation performance using either RGB gray values or CIE xy values. Our real-time assessment of smartphone displays can aid in reducing energy consumption and improving user health.

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