Changing the Intensity on the Caustic of Autofocusing Chirp Beams Depending on the Incident Beam Amplitude

Abstract

We have obtained an expression for the amplitude and intensity of the field along the caustic line, which is formed during autofocusing when the generalized lens is illuminated. Two types of the incident beam amplitude are considered: the product of a power and generalized exponential function; fractional-rational amplitude without singularities. With different ratios between the parameters, the dependence of intensity on distance will have a diverse form – increasing, decreasing, with a maximum, with a minimum. At the same time, the edge values can also be different: zero, positive number, infinity.