METHOD OF MEASUREMENT OF DISPLACEMENT Russian patent published in 2018 - IPC G01B11/14 G01S17/32 

FIELD: measuring equipment.

SUBSTANCE: invention relates to the field of precision instrumentation. Method for measuring nanodisplacement is that the object is irradiated with laser radiation, the radiation reflected from the object interfering with the laser is registered with an integrated photodetector. Convert the laser radiation into an electrical autodyne signal. Wavelength of the laser radiation is modulated by a current of power supply of a given frequency and amplitude. Amplitude is changed according to the harmonic law. Detected signal is decomposed into a Fourier spectral series and a series of Bessel functions. Amplitude of the 2n^th (S_2n) and 2n+2-th (S_2n+2) harmonics of the spectrum or 2n+1-th (S_2n+1) and 2n+3-th (S_2n+3) of the harmonics of the spectrum of the autodyne signal, with respect to S_2n/S_2n+2=(J_2n(σ)/(J_2n+2(σ)) or S_2n+1/S_2n+3=(J_2n+1(σ)/(J_2n+3(σ)), respectively, the value of the amplitude parameter of the phase modulation σ. Magnitude of the stationary phase of the autodyne signal is determined by the formula θ=arctg(S_2n+1/S_2n(J_2n(σ)/(J_2n+1(σ)), nanooperation ΔL reflectors are found by the formula: , where ω₀ – frequency of laser radiation, c – speed of light, J_2n, J_2n+2, J_2n+1 and J_2n+3 – Bessel functions.

EFFECT: technical result consists in providing the possibility of increasing the accuracy of measuring the movements of the micro- and nanometer range.

1 cl, 4 dwg