title: Wide-area scanner for high-speed atomic force microscopy.
abstract: High-speed atomic force microscopy (HS-AFM) has recently been established. The dynamic processes and structural dynamics of protein molecules in action have been successfully visualized using HS-AFM. However, its maximum scan ranges in the X- and Y-directions have been limited to ~1 μm and ~4 μm, respectively, making it infeasible to observe the dynamics of much larger samples, including live cells. Here, we develop a wide-area scanner with a maximum XY scan range of ~46 × 46 μm(2) by magnifying the displacements of stack piezoelectric actuators using a leverage mechanism. Mechanical vibrations produced by fast displacement of the X-scanner are suppressed by a combination of feed-forward inverse compensation and the use of triangular scan signals with rounded vertices. As a result, the scan speed in the X-direction reaches 6.3 mm/s even for a scan size as large as ~40 μm. The nonlinearity of the X- and Y-piezoelectric actuators' displacements that arises from their hysteresis is eliminated by polynomial-approximation-based open-loop control. The interference between the X- and Y-scanners is also eliminated by the same technique. The usefulness of this wide-area scanner is demonstrated by video imaging of dynamic processes in live bacterial and eukaryotic cells.
authors.affiliation: Department of Physics, College of Science and Engineering, Kanazawa University, Kanazawa 920-1192, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Watanabe
authors.forename: Takayuki
authors.initials: T
authors.lastname: Uchihashi
authors.forename: Toshihide
authors.initials: T
authors.lastname: Kobashi
authors.forename: Mikihiro
authors.initials: M
authors.lastname: Shibata
authors.forename: Jun
authors.initials: J
authors.lastname: Nishiyama
authors.forename: Ryohei
authors.initials: R
authors.lastname: Yasuda
authors.forename: Toshio
authors.initials: T
authors.lastname: Ando
mesh_terms: D000199:Actins / Q000378:metabolism; D001412:Bacillus subtilis / Q000166:cytology; D001433:Bacteriolysis; D004705:Endocytosis; D006367:HeLa Cells; D006801:Humans; D018625:Microscopy, Atomic Force / Q000295:instrumentation*; D009113:Muramidase / Q000378:metabolism
chemical_list: D000199:Actins; D009113:Muramidase