
THE POSSIBILITY OF FOCUSING THE ACOUSTIC RADIATION INTO A REGION LESS THAN THE DIFFRACTION LIMIT
Author(s) -
Oleg V. Minin,
Igor V. Minin
Publication year - 2019
Publication title -
interèkspo geo-sibirʹ
Language(s) - English
Resource type - Journals
ISSN - 2618-981X
DOI - 10.33764/2618-981x-2019-8-100-103
Subject(s) - optics , diffraction , lens (geology) , focus (optics) , acoustics , limit (mathematics) , cylinder , physics , metamaterial , transverse plane , engineering , mathematics , mechanical engineering , mathematical analysis , structural engineering
Metamaterial lenses are used to achieve sharp focus in the optical range and in acoustics. Recently, an innovative concept called "acoustojet" was proposed, in which it is possible to focus the acoustic energy in an area with transverse dimensions less than λ/2. By numerical simulation and the experiment it is shown that sharp focusing is possible in acoustics. It is demonstrated by choosing the appropriate size of a simple cylindrical lens (a mesoscale particle in the shape of a cylinder) and relative speed of sound between the lens material and the environment. In this case, an acoustic jet with a half-width (FWHM) less than λ/2 can be formed. The results give rise to a new era of obtaining an acoustic image with superresolution. Such devices are necessary in electronics, materials science, medicine, biological science, etc.