A super-high brightness and excellent colour quality laser-driven white light source enables miniaturized endoscopy

Shuxing Li; Linhui Huang; Yunqin Guo; Le Wang; Rong-Jun Xie

doi:10.1039/d3mh01170d

A super-high brightness and excellent colour quality laser-driven white light source enables miniaturized endoscopy

Mater Horiz. 2023 Oct 2;10(10):4581-4588. doi: 10.1039/d3mh01170d.

Authors

Shuxing Li¹, Linhui Huang¹, Yunqin Guo¹, Le Wang², Rong-Jun Xie^{1

3}

Affiliations

¹ Fujian Provincial Key Laboratory of Surface and Interface Engineering for High Performance Materials, College of Materials, Xiamen University, Xiamen 361005, China.
² College of Optical and Electronic Technology, China Jiliang University, Hangzhou 310018, China. calla@cjlu.edu.cn.
³ State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China. rjxie@xmu.edu.cn.

PMID: 37584153
DOI: 10.1039/d3mh01170d

Abstract

A laser-driven white light source promises intrinsic advantages for miniaturized endoscopic illumination. However, it remains a great challenge to simultaneously achieve high brightness and excellent colour rendition due to the shortage of highly efficient and thermally robust red-emitting laser phosphor converters. Here, we designed CaAlSiN₃:Eu@Al (CASN@Al) converters with neglectable efficiency loss by tightly bonding all-inorganic phosphor films on an aluminium substrate. A layer-by-layer phosphor converter (LuAG/CASN@Al), i.e., stacking a green-emitting Lu₃Al₅O₁₂:Ce (LuAG) layer on CASN@Al, was constructed to enhance light conversion efficiency and reduce reabsorption loss under blue laser excitation, which thus produces an excellent white light source with a luminous efficacy of 258 lm W^-1 and a colour rendering index of 91. A miniaturized endoscopy with a coupling efficiency twice that of the commercial white LEDs was demonstrated by using the laser-driven white light and showed a central illuminance as high as 52 730 lx, more vivid images and long-term reliability.