Machining of optical microstructures with 157 nm laser radiation

The precision machining of glass by laser ablation has been expanded with the short wavelength of the 157 rim of the F2 excimer laser. The high absorption of this wavelength in any optical glass, especially in UV-grade fused silica, offers a new approach to generate high quality surfaces, addressing also micro-optical components. In this paper, the machining of basic diffractive and refractive optical components and the required machining and process technology is presented. Applications that are addressed are cylindrical and rotational symmetrical micro lenses and diffractive optics like phase transmission grating and diffractive optical elements (DOEs). These optical surfaces have been machined into bulk material as well as on fibre end surfaces, to achieve compact (electro) - optical elements with high functionality and packaging density. The short wavelength of 157 rim used in the investigations require either vacuum or high purity inert gas environments. The influence of different ambient conditions is presented.