We propose a new non-contact AFM scanning method allowing to retrieve on-the-fly, the parameters that define the potential energy curve between the tip and the sample. The underlining theory and methodology are introduced using the Morse potential as a case study. The method involves feedback control that maintains tip sample distance close to the maximum of the force gradient, and measurement of the harmonics of the frequency shift of the cantilever. Both analytical and numerical solutions are shown, with the latter capable of accommodating finite amplitude of drive of the cantilever and a finite range of position modulation of the tip-sample distance. The measurement of the Morse potential was successfully demonstrated on a Si (111) surface. Assigning the Morse parameters to color channels, such as RGB, one would obtain a color image expressing differences in the local potential landscape and/or the species of the atoms.