Experiments and theoretical analyses of non-diffracting beams interference

The interference pattern and locus of interference fringes of two non-diffracting beams are analyzed. Two non-diffracting beams are generated when an axicon is illuminated by two coherent beams, which are produced by two pinholes illuminated by a monochromatic wave. Based on the non-diffracting property of an axicon in oblique illumination, the interference field is the linear superposition of each non-diffracting field of non-diffracting beam. The locus of interference fringes is analyzed to be hyperbola according to the zero-point formula of zero-order Bessel function. Results show that the distance of the two centers of interference field is proportional to the distance of the two pinholes and the distance between the axicon and interference field. The experimental results are in good agreement with the numerical simulation.