Theoretical modeling of generation of hat-top intensity profile from Gaussian beam by means of a two-stage beam shaper

摘要

Both theoretical and experimental results of an optical beam shaping system are investigated in this report. The described system is a two-stage beam shaping device including a fiber-bundle and a prism-duct. A source light is used to illuminate the fiber-bundle and the image of output beam is captured by a CCD camera. The fiber-bundle output beam shape shows a linear arrangement of circular spots lights, which are placed in a rectangular cross section of about 21.37 mm × 2.44 mm. In another study, the photograph picture of the prism output beam is taken by a digital camera. The prism output beam cross section is a square shape with a dimension of about 4 × 4 mm~2. According to the experimental results, the prism duct converted a Gaussian beam profile with multiple-peak distribution to a hat-top beam profile with the uniform intensity distribution. For theoretical investigations, using ZEMAX software a simulation is performed to analyze the beam shaping design. By proper modeling the output beam shape and radiance profiles in position space and angle space of the fiber-bundle and the prism duct are investigated. Theoretical radiance profiles are obtained by using simulated images and results are in agreement with the experimental results.