METHOD FOR VISUALIZING PHASE OPTICAL DENSITY FIELDS IN GASEOUS AND CONDENSED MEDIA AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2021 - IPC G01P5/26 G01B11/24 

FIELD: measurement equipment.

SUBSTANCE: invention relates to measuring technology and can be used in experimental hydro- and gas dynamics, thermophysics, oceanology, as well as in industrial technologies related to the need to study the fields of phase optical density in gas, condensed and reactive media, flames and jets. The claimed method for visualizing the phase optical density fields of gas and condensed media consists in directing a probing light field into the medium under study, forming a space-frequency Fourier spectrum of perturbations induced in the probing light field by the medium under study, sequentially performing isotropic Hilbert filtering of the space-frequency Fourier spectrum of the perturbed field, the inverse Fourier transform, the Hilbert image of light field disturbances is projected onto the video camera’s photo matrix and a frame-by-frame sequence of images is subjected to computer processing. Moreover, the probing field is formed in the studied medium in the form of spatially configured monochromatic or polychromatic Bessel beams. The device implementing the method contains a sequentially arranged light source, a probing light field shaper, a Fourier lens, in the frequency plane of which an isotropic Hilbert filter is placed, and a digital video camera connected to a computer. The light source is a source of configured Bessel beams whose Fourier spectrum is consistent with the phase structure of an isotropic Hilbert filter. The device can be made, for example, so that the shaper of configured Bessel beams is made in the form of a sequentially arranged shaper of concentric ring r, g, b beams and an axicon made in steps.

EFFECT: an increase in accuracy and expansion of functionality for Hilbert visualization of the spatial structure of the optical phase density field in condensed, gaseous and reactive (flame) media.

4 cl, 5 dwg