Second-level fast sintering enables high-brightness light source for visible light communication

Laser-driven light sources are critically important for lighting, display, and communication systems. However, the traditional phosphor ceramics used in these light sources suffer from low light conversion efficiency, low color rendering index and narrowly tunable color temperature. Here we present a approach of rapid pulsed high-temperature sintering technology to fabricate phosphor ceramics with both dense and grain refined microstructure simultaneously. It results in a 31% improvement in light conversion efficiency, markedly better color mixing uniformity, and 1.5-fold increased fracture toughness for Lu3Al5O12:Ce ceramics. Moreover, this method enables the Lu3Al5O12:Ce–CaAlSiN3:Eu composite ceramics with a 95-fold enhancement in quantum efficiency, showing white light under blue laser excitation with a color rendering index of 93 and good reliability. An accurate emission wavelength prediction model was also established with an interval below 5 nm from 495 to 605 nm, and achieved a broad color temperature range (1996-9803 K). This research enhances the development of high-performance light sources toward lighting and indoor/underwater visible light communication. This study reports a rapid sintering technique with machine-learning-guided design to fabricate phosphor ceramics within only 10 s. Such ceramics show excellent performance in the laser-driven light sources for visible light communication.