The force apply on the surface is directly correlated to the spring constant of the cantilever : lowest spring constant = lowest force
Contact mode : A probe of nanometric size scans the surface using piezoelectric motors. Laser detection maintains a constant bending of the cantilever during the measurement. The movements of the vertical piezoelectric motor are recorded vertical to reconstruct the surface. Mapping of friction is performed with the torsion of the cantilever (LFM).