Direct replication of a glass micro Fresnel zone plate array by laser irradiation using an infrared transmissive mold.

It is not yet possible to fabricate micrometer-scale, glass optical components with nanometer-scale precision. Glass thermal imprinting enhances production efficiency. However, dimensional changes caused by shrinkage are inevitable because of phase transitions. Replication is very difficult when high-level pitch precision is essential. We used an infrared-transparent silicon mold and a CO2 laser to perform replica-type, thermal surface texturing at the nanoscale level; we analyzed a glass Fresnel zone plate array to this end. The Fresnel zone plate array was 10 x 10 mm(2) in area and featured a 20 x 20 array. The individual Fresnel zone plate diameter was 500 mu m and had 21 rings of minimum linewidth 2.9 mu m and height 737 nm. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement