Abstract
The invention concerns a microscopic system with atomic force, comprising a probe tip placed on one end of a lever arm (2), oscillating means (1) adapted to oscillate said probe tip substantially based on the fundamental frequency of said lever arm, said system including control means (7) for controlling said oscillating means to vary the oscillation frequency of said tip based on a plurality of harmonics of said lever arm. The invention is characterized in that said control means comprise an input receiving a parameter representing an operating threshold of said system, to vary the oscillation frequency of said tip based on at least one harmonic of said lever arm when said signal corresponds to a state of said system higher than said operating threshold.