Color measurement for RGB white LEDs in solid-state lighting using a BDJ photodetector

Color measurement and white balancing for RGB white LEDs was demonstrated by a blue-violet enhanced BDJ photodetector, which can simultaneously determine the centroid wavelength and the radiant power of LEDs from 380 nm to 780 nm. This BDJ photodetector directly gave the chromatic coordinates of a LED that was approximated as a monochromatic stimulus due to its narrow spectrum compared with the CIE color-matching functions. Maximal simulated and experimental errors Δu′v′ to the target white point of the white balanced RGB LEDs was 0.0154 and 0.0214. The BDJ photodetector also performed to be sensitive to the spectrum variation characterized by CCT, and was preferable as a sensor for monitoring the white point.