An Optical–Electrical Decoupling Strategy for Fabricating Wood‐Waste‐Derived Laser‐Driven Diffusers for Specialized Lighting Inspired by Atmospheric Sunlight Scattering

ABSTRACT Conventional lighting devices exhibit low brightness and safety hazards (including short circuits and electrical sparks), limiting their use in specialized environments like historic buildings, ammunition depots, and underground mines. To overcome these challenges, laser‐driven wood fiber diffusers (LWFD) were developed using renewable, low‐cost wood waste. This eco‐friendly approach involves a simple, low‐energy process with delignified wood fibers, polyethylene glycol diacrylate (PEGDA), and yttrium aluminum garnet phosphor, followed by photocuring. The refractive index mismatch between the fibers (n ≈ 1.53) and PEGDA (n ≈ 1.42) induces Mie scattering, converting laser beams into uniform light. The isotropic structure ensures angle‐independent irradiation and uniform 3D illumination. With optimized phosphor content (0.2 wt.%) and fiber loading (2.5 g), LWFDs achieve a coefficient of illumination variation (CIV) of 4.10%, ensuring excellent uniformity. LWFDs remain stable from 100°C to −20°C and maintain a surface temperature of about 30°C during prolonged laser exposure. They emit stable white light (CIE coordinates: 0.33, 0.33), with photoluminescence intensity increasing linearly with laser power. LWFDs enable long‐distance wireless lighting, eliminating voltage drops, high wiring costs, and safety hazards, making them ideal for railways, historic buildings, and underground mines. The use of wood waste also supports sustainable resource recycling.