Functional glass surface by femtosecond laser texturing

Functionalizing glass surfaces to achieve simultaneous antireflective and antifogging properties is highly desirable for numerous technological applications, ranging from daily device screens and solar windows to optoelectronic, medical and automotive devices. In this study, we present a maskless, coating-free femtosecond laser texturing approach to fabricate nanostructures on soda-lime and BK7 glass substrates. Using a 1030 nm femtosecond fiber laser Jasper X1 (Fluence, Poland), we investigated the influence of laser fluence, pulse accumulation, and repetition rate on the resulting surface morphology. Depending on the applied parameters, the formation of high- and low-spatial-frequency laser-induced periodic surface structures (HSFL, LSFL) and homogeneous cone-like nanostructures were achieved. Optical characterization revealed a significant broadband reduction in specular reflectance in the visible spectrum, decreasing from 8–10% for untreated glass to 1–2.5% for the laser-modified samples. Simultaneously, the textured surfaces exhibited exceptional antifogging performance, effectively suppressing moisture accumulation while preserving structural transparency. Crucially, the functionalized substrates maintained high optical clarity, with diffuse transmittance remaining strictly below 1% for BK7 and below 0.25% for soda–lime glass. These results demonstrate that ultrashort pulse laser processing is a highly effective, single-step method for producing durable, multifunctional optical components.