Study on optical characteristic variations according to spectrum changes of RGBY multi-chip LEDs

Abstract

Recently, various multi-chip LEDs have been developed as the efficiency of red, green, and blue LED chips is improved. RGBY multi-chip LEDs have a high color rendering index, but there is no research on the change of optical characteristics according to the peak wavelength, peak power and bandwidth of the spectrum. In this study, the spectra of commercially available RGBY LEDs are approximated by the Gaussian model and the effect of the spectral variations of red, green, blue and yellow regions on the color rendering indices was examined. CCT and CRI changes due to peak wavelength shift and change in full width at half maximum (FWHM) were simulated and a CRI higher than 98 at 2500 K to 6000 K color temperature range was resulted.