Spectral effects of AFM tip geometry

摘要

It is known that tactile measurement systems like AFM, besides their resolution limit in spatial frequency, introduce distortions in the measured surface functions. Usually the distortion process is described by morphological operations, which are also used for reconstruction approaches. These operations do not deliver analytical information on the spectral consequences of the distortion process. Since the measurement and signal chain are time dependent systems and the signal processing is often based on time resp. spatial frequency analysis, such analytical estimations are highly desirable. The paper describes a method to characterize the distortion process in the spectral domain, leading to a spectral description of the resulting signal. The presented approach is neither based on morphological image processing nor convolution and can be utilized to determine the obtainable quality of AFM measurements and the limits of surface reconstruction.