Fabrication of microstructures by picosecond laser

Microstructures assume crucial role in preparation of functional surfaces, such as self-cleaning, anti-icing and drag reduction. In the paper, picosecond laser is used for the fabrication of the microstructures by the balanced photothermal and photochemical action. In order to improve the controllability of structural dimensions, we reported on fabrication of smooth swelling by picosecond laser irradiation of two-layer substrate. The upper layer is swelling doped PMMA; the lower layer is black acrylic. This work first obtained different microlines by tuning the scanning speed through focusing on the interface. Then, different swelling structures were fabricated by adjustment of laser irradiation time. Further, the dependence of swelling morphology on irradiation time and laser power were studied. For the different swellings, the microlens array was obtained by replication and the imaging performance was tested. This demonstrated the possibility of the method for preparation of the microlens array and other functional microstructures.