Optical model of porous glasses using genetic algorithms

Porous surfaces on glasses have been proved to be effective in suppressing light reflection due to the continuous variation in the refractive index with thickness. The porous structures were fabricated on BK7 glass by neutral-solution leaching process, and broadband transmittance was measured by a spectrometer. An optical model was applied to determine gradient refractive index profiles of porous glasses using a genetic algorithm. Scanning electron microscopy (SEM) analysis of the nanostructure variants will be shown, along with spectral transmittance that is matched to theoretical models. This model has potential applications in tracking optical properties according to the depth of nanostructures measured by SEM, or obtaining gradient refractive index profiles of porous glasses by the measured transmittance. Therefore, it is useful to optimize experimental condition for special optical properties of porous glass.