Laser-based surface multistructuring using optical elements and the Talbot effect

Abstract

We present a laser based technique combined with the Talbot effect for microstructuring surfaces. The use of the Talbot effect is introduced as a solution to avoid damage of the periodic object used for micropattering different surfaces during the ablation process. The fabrication of two periodic objects (a mask and a microlens array) for micropattering surfaces and the identification of their Talbot planes is presented. A metal foil is ablated at distances corresponding to selected Talbot planes of the periodic objects. The setup allows us to design the desired pattern and the result is a multistructured surface with a high number of identical microholes, achieving a minimum diameter around 4μm. The different aspect of the periodic object working in direct contact and working at these Talbot distances is shown. These pictures reveal the advantages of working of using Talbot effect for a rapid, repeatable and no-contaminant multistructuring. Some industrial applications are illustrated.