We have established a non-contact polishing process for thermoplastic, polymeric microlenses and –prisms with dimensions of up to 50 μm, including sharp convex tips and rims with sub-μm details. The required 3D master structures were fabricated using direct laser-writing lithography with two-photon absorption. Master structures were replicated into poly(methyl methacrylate) through a poly(dimethyl siloxane) intermediate copying step and exposed with 172 nm UV light. Due to the reduction of glass transition temperature in a surface-confined layer, roughness in the range of more than 100 nm could subsequently be smoothed-out to below 10 nm by annealing the surface by heating.
Helmut Schift, Nachiappan Chidambaram, Mirco Altana, and Robert Kirchner, "Selective surface smoothening of 3D micro-optical elements," Proc. SPIE 10144, Emerging Patterning Technologies, 101440B (Presented at SPIE Advanced Lithography: February 28, 2017; Published: 21 March 2017); https://doi.org/10.1117/12.2256358.
Conference Presentations are recordings of oral presentations given at SPIE conferences and published as part of the conference proceedings. They include the speaker's narration along with a video recording of the presentation slides and animations. Many conference presentations also include full-text papers. Search and browse our growing collection of more than 12,000 conference presentations, including many plenary and keynote presentations.