A feedback paradigm for achieving high resolution positioning for applications requiring repetitive motions such as image scanning in atomic force microscopy (AFM) is presented. The feedback scheme achieves very high resolution by compromising on the bandwidth of the device, even at high speeds, by making the device equivalent to a low bandwidth band pass filter with the central frequency corresponding to scan frequency. Application of this scheme on a flexure based stacked piezoactuated AFM scanner has demonstrated subnanometer resolution enabling atomic scale stick-slip images on mica, impossible otherwise. Experiments at high scan speeds using this scheme improved the positioning resolution by 96%.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)