METHOD OF DETERMINING SMALL-SCALE DEFORMATIONS OF WAVE FRONT OF LIGHT BEAM Russian patent published in 2024 - IPC G01M11/02 

FIELD: optics.

SUBSTANCE: invention relates to optics and quality control of optical systems or elements. Method involves directing a light beam with wavelength λ on the optical system and determining the position of the plane P_max, for which the peak intensity of the light beam has a maximum value I_max. Distance L_max from the plane P_max to the plane P in contact with the last surface of the optical system, and the beam diameter D in the plane P are measured. Light beam intensity distribution is measured in coordinates of planes remote from the plane P_max, which is determined for each interval of spatial frequencies Δv_i, obtained as a result of dividing the range from v_min to v_max into m consecutive intervals of spatial frequencies Δv_i. Determining the value w'_i(x,y) for each interval Δv_i by numerical solution of equation. By selecting from w'_i(x,y) Fourier series terms containing harmonics satisfying the conditions when one harmonic ordinal number (μ_ix,μ_iy) exceeds value μ_i-1 and both (μ_ix,μ_iy) do not exceed the value μ_i, a component w*_i(x,y) is made from the sum of the selected terms of the Fourier series. Wave front deformations w(x,y) are determined by summing up all components.

EFFECT: higher accuracy and reliability.

1 cl, 3 dwg