Narrow-Band Green-Emitting RbSr4(BO3)3:Eu2+ Phosphor Glass Composite for Wide-Color-Gamut Laser Displays

Laser phosphor display is promising for next-generation high-quality display technology due to its high brightness, wide color gamut, and low speckle. However, the lack of high performance narrow-band green emitters with robust laser resistance remains a critical bottleneck. Herein, we develop RbSr 4 (BO 3 ) 3 :Eu 2+ (RSBO:Eu 2+ ) as a narrow-band green emitter, which exhibits an emission peak at 526 nm with a narrow full width at half maximum of only 50 nm under blue light excitation. The highly dense and rigid host framework effectively suppresses lattice relaxation and electron–phonon coupling despite Eu 2+ occupying multiple cation sites in RSBO. Highly stable RSBO:Eu 2+ was further embedded into a low-melting P 2 O 5 -Al 2 O 3 -B 2 O 3 -Na 2 O glass matrix to fabricate a phosphor-glass composite (RSBO:Eu-PGC), demonstrating good thermal stability and a high saturation threshold exceeding 40 W/mm 2 . The corresponding rotating phosphor wheel maintained a low surface temperature of 79.9°C under 40 W/mm 2 blue-laser irradiation, effectively mitigating thermal degradation. A prototype laser display system using a rotating wheel integrating RSBO:Eu-PGC and K 2 SiF 6 :Mn 4+ -PGC achieved a wide color gamut of 107% National Television System Committee (NTSC) standard, which highlights the great potential of narrow-band green-emitting RSBO:Eu-PGC for laser phosphor display applications.