The determinist behavior of the femtosecond ablation process allows morphing features well under the diffraction limit by utilizing the thresholding effect, down to the nanometer scale. Because there are a vast range of applications where scaling down the size of the features is a major concern, we investigate the use of superresolving pupil plane filters. As is well known, these filters redistribute the focused optical intensity for a narrower bright spot and, as a trade-off, increase the sidelobes. However, this drawback can be rendered insignificant if all the outer optical power is kept under the determinist threshold value. Two types of pure absorbing binary filter have been tried, giving credence to a size reduction of the ablations in fused silica.
© 2007 Optical Society of America
Lasers and Laser Optics
Original Manuscript: April 3, 2007
Manuscript Accepted: May 26, 2007
Published: July 25, 2007
Michele Merano, Gilbert Boyer, Alexandre Trisorio, Gilles Chériaux, and Gérard Mourou, "Superresolved femtosecond laser ablation," Opt. Lett. 32, 2239-2241 (2007)