Comment on "The long range voice coil atomic force microscope" [Rev. Sci. Instrum. 83, 023705 (2012)].

In a recent article Barnard et al. described the use of voice coil actuators to realize a large range scanner for probe microscopy. The results reported are interesting, but the idea is not new. In two preceding papers [1998, 1991] we had described a large coverage, wide dynamic range scanner based on homemade voice coil actuators, while Garcia Cantu and Huerta Garnica [1986] had already used inductive scanners for tunneling microscopy. Lamentably, none of these articles was cited by Barnard et al.