Optimal radiant flux selection for multi-channel light-emitting diodes for spectrum-tunable lighting

Abstract

To synthesise a spectrum with a given radiant flux by multi-channel light-emitting diodes, different light-emitting diodes should have different radiant fluxes to maximise the light-emitting diode flux utilisation rate defined by the radiant flux of the light-emitting diode’s contribution to the synthesised spectrum divided by the rated radiant flux of this light-emitting diode. The optimal rating radiant flux algorithm for each light-emitting diode is achieved by applying the norm-reducing process and full-search method to the norm region of the spectra. As a result, light-emitting diodes with a broader full-width half maximum, such as phosphor-converted light-emitting diodes, are usually set at a high power level and the rest of the light-emitting diodes can be set to either medium or low power levels. Furthermore, the high-power light-emitting diode can be decomposed to some low-power light-emitting diodes to reduce both heat generated and light-emitting diode price.