Flat-top beam profile generated using a fiber-bundle prism-coupled beam shaper

In this paper, an optical beam shaping system is theoretically and experimentally investigated. The optical system design software ZEMAX is used to simulate and analyze the reported beam shaping design. By using this software ray tracing diagrams are presented with the aim of studying the direct beam propagation, total reflection rays, and the lost rays. The prism duct output beam shape and radiance profiles in both position space and angle space are also studied. For experimental investigation, a two-stage beam shaping design including a fiber-bundle and a prism duct is used. A source light is used for the fiber-bundle illumination and the photograph image of the output beam is taken by a digital camera. The fiber-bundle output beam cross section is a rectangular shape with a dimension of 25.65 mm width and 2.44 mm height. In another experiment, the prism output beam is captured by a CCD camera. The prism output beam shape depends on the prism exit face, which is a rectangle (4.15 mm × 3.55 mm) for this case. The image date of the prism output beam is converted to a response curve, which is approximately a flat-top profile. The experimental image profiles are compared with the simulated image profiles and there is a good agreement between the observed results.

Research Highlights
► Theoretical and experimental investigations for a beam shaping system reported.
► Ray tracing and image formation concerning the shape of final output beam are given.
► An extended beam shape converges into a small-sized cross section with a flat-top profile.
► Experimental intensity profiles are obtained by using captured images and results are in agreement with the predictions.
► Potential applications of device are in optical pumping, power transmission, image formation, and modification.