Multicolor Borogermanate Glass Films for High-Brightness Wide-Color-Gamut Laser-Driven Projection Display

Abstract

The urgent demand for color conversion composites in laser-driven projection display technology has highlighted fluorescent phosphor-in-glass films (PiGF) as a promising material. The newly designed borogermanate glass matrix is proven to be a versatile platform for incorporating various commercial phosphors to create multicolor PiGFs. Notably, the controlled interfacial interaction leads to exceptional luminescent performance, particularly in achieving unprecedented quantum efficiency for rare earth ions activated (oxy)nitrides, which are of critical importance. By conducting comparative analyses in static and rotating excitation modes, the combined effects of thermal quenching and intensity quenching on luminescence saturation under high-power blue laser irradiation are explored. The developed rotating phosphor wheel, featuring an intricate pattern structure, delivers high-brightness high-quality white light with a luminous flux (LF) of 1665 lm @26.8W mm⁻², luminous efficacy (LE) of 84.4 lm W⁻¹, and color rendering index (CRI) of 92. Introducing the four-color “polygon scheme” significantly expands the color gamut of laser displays to 114% NTSC, thereby enhancing the visual experience with superior color reproduction.