Diffraction property of an axicon in quasi-monochromatic light

For analyzing the diffraction property of an axicon in quasi-monochromatic illumination,based on the analyses of the diffraction property of an axicon illuminated by a monochromatic plane wave and the property of quasi-monochromatic light that it can be regarded as superposition of monochromatic components of differential frequencies,the intensity distribution of the diffraction pattern of an axicon in quasi-monochromatic light was deduced.According to the numerical simulation and experimental results,the difference between the diffraction patterns generated by quasi-monochromatic light and monochromatic light was compared.Results show that the intensity distribution of an axicon in quasi-monochromatic light is given by the sum of intensity of individual component,and the diffraction fringes are less than those produced by monochromatic light.Moreover the off-axis intensity attenuates more rapidly than that of monochromatic waves.