Patent ID: 11076241

Abstract:
The construction has two piezoelectric transducers with radiating apertures shaped as sections of spherical surface one is concave, the second is convex, of sufficient wave sizes D/λ>10, where D is the diameter of the aperture, λ is the wavelength of the emitted pump signal). For each piezoelectric transducers radii of curvature R0, focal lengths F0 and focal spots radii r0 with a wave length of radiated signal are the same and are related by r0×R0=0.61×λ×F0. Piezoelectric transducers with radiating apertures shaped as sections of spherical surface are provided with shielding elements, hydro-, electric- and noise insulation and one of them with convex aperture is made with an open axial hole with radius r=(2÷3)×r0 in the central part of the convex spherical surface of the aperture.