Tunable-spectrum Mn2+ doped garnet transparent ceramics for high-color rendering laser lighting

Laser diodes (LDs) packaged with transparent ceramics show the low thermal expansion coefficient and high thermal conductivity, but there is a problem of the low color render index (CRI) owing to the lack of red component in current transparent ceramics. Mn2+ doped garnet transparent ceramics with adjustable color from yellow to red have been prepared via a solid-state reaction-vacuum sintering process, which have a high transmittance of 78.6% at 800 nm. Two main emission peaks of this ceramic are monitored at 590 and 749 nm, and the gratifying luminous performance improvement is obtained due to the charge compensation effect, electron cloud expansion effect, and efficient energy transfer. LD system fabricated with the obtained ceramics and blue LD shows a high-CRI of 80, low correlated color temperature of 4098 K, and good luminous efficiency of 96.91 m/W.

Automated summary

By doping garnet transparent ceramics with adjustable color, the luminous performance of the laser diode system has been significantly improved, achieving a high color rendering index and good luminous efficiency.