On the fundamental possibility of creating a laser reference for a local acoustic pressure in a fluid

The possibility of establishing an unambiguous relation between the amplitude of a local acoustic pressure in a fluid and the parameter laser radiation scattered on microparticles located in this region has been studied. The fundamental difficulty of the problem, which has not been overcome in preceding works, is due to the uncontrollable phase taper of probe laser beams even in the simplest case of a harmonic acoustic wave. It has been shown that the inclusion of nonlinear components of the phase taper makes it possible to unambiguously express the amplitude of the local excess pressure in the region of interference of two crossing laser beams in terms of the parameters of the medium and the parameters of scattered radiation. This indicates the fundamental possibility of creating a laser reference for acoustic pressure in fluids.