Resonator measurement system having at least MEMS and/or NEMS, comprising: an optomechanical device comprising at least one resonating element at at least one resonance frequency of fr and at least one optical element whose optical index is sensitive to the displacement of the resonating element, excitation circuitry of exciting the resonating element at least at one operating frequency of fm, injection device for injecting a light beam whose intensity is modulated at frequency f1=fm+Δf in the optomechanical device, a photodetection device configured measure the intensity of a light beam coming out of the optomechanical device, the intensity of the measurement beam having at least one component at frequency Δf.