Patent ID: 8065908

Claim:
A scanning probe microscope for oscillating a cantilever and performing relative scanning between said cantilever and a sample, comprising: exciting means for exciting said cantilever; a sensor for detecting displacement of said cantilever; reference wave generating means for generating a reference wave signal that has a frequency based on an excitation signal of said cantilever and is of fixed phase difference with respect to said excitation signal; trigger pulse generating means for generating a trigger pulse signal whose pulse position changes dependent on the phase of oscillation of said cantilever, on the basis of the displacement of said cantilever; and phase signal generating means for generating a signal dependent on the magnitude of said reference wave signal at said pulse position as a phase signal of said cantilever oscillation, on the basis of said reference wave signal and said trigger pulse signal; wherein said reference wave generating means generates a signal having the same frequency as said excitation signal and of fixed phase difference with respect to said excitation signal as said reference wave signal; wherein said trigger pulse generating means generates, as said trigger pulse signal, a pulse signal that expresses the position on a time axis of an oscillation waveform obtained from the displacement of said cantilever; and wherein said trigger pulse generating means generates said trigger pulse signal at a position on the oscillation waveform corresponding to the timing of contact or closest approach of said cantilever to said sample.