Fast microstructuring of silica glasses surface by NIR laser radiation

• We demonstrated the new laser technology for glass microstructuring.
• We created and investigated diffraction phase gratings and random phase plate.
• We used glass with different composition.

The glass surface microstructuring technology using laser radiation with NIR wavelength (λ=1.064 μm) was revealed in this work. Glass plates were placed on the cellular graphite surface. Focused laser radiation passed through the glass plate and interacted with cellular graphite. The radiation heated the graphite surface and thus the high temperature influenced the back side of the glass plate. After consecutive laser scans, having certain periods and interruptions of laser radiation, the microstructures with depth ~0.5 μm were formed. Besides, in this work we suggested the method to calculate optical characteristics of formed elements. It was experimentally shown that these microstructures could be used to form phase diffraction gratings (PDGs) and random phase plates (RPPs). We experimentally demonstrated the possibility of these elements being used as RPPs which are suitable for multimode laser radiation homogenization and as PDGs which are suitable for laser simultaneous processing of metal films.