Measurements of the nanovibration amplitude by a frequency-modulated laser autodyne

A method to measure the reflector nanovibration amplitudes from the low-frequency spectrum of a signal from a frequency-modulated laser autodyne is suggested. The frequency-modulated autodyne signal at the harmonic vibrations of the reflector is theoretically described, and relationships for the autodyne signal spectral components are derived using expansions into Fourier and Bessel series. The respective experimental setup is considered, and measuring data for the nanovibration amplitudes of the reflector and the autodyne spectra are considered.