Research on the detector-based high stable color tunable LED standard source

摘要

A detector-based high stable color tunable LED standard source has been designed in our previous work. In this paper the design is improved to obtain higher luminance stability. Addition to four narrow-band detectors monitoring the light output of the LEDs, a V(λ) detector is also employed to monitor the luminance of the source. A general controller controls the drive currents of the four LEDs according to the feedback signals of the five detectors. The temperature of the detectors is controlled at 40±0,1 °C with their stability within 0,01%. The temperature of the LEDs is also controlled constant. The details in the design of the standard source are introduced.