Modeling of a focal pi-Shaper using the ray-mapping method

Abstract

Subject of study. The modified ray-mapping method for the synthesis of a two-component beam-shaper is studied. These beam-shapers are used to obtain a uniform intensity flat-top profile. Aim of study. The development and approbation of an algorithm for the simultaneous synthesis of a pair of a two-component laser focal pi-Shapers is the aim of the study. Method. The algorithm for calculating the design parameters of a pair of freeform optical surfaces is based on simultaneous ray tracing in the direct and reverse directions by modifying the ray-mapping method. Main results. It is shown that the implemented algorithm works efficiently enough with a significant distance between the components. The calculated model of the beam-shaper has a residual transverse aberration Δymax′<0.82mrad; the mean-square deviation of the intensity distribution of the output radiation from the required one is no more than 1% for the refractive surface tolerance equal to 0.05 µm. The effective conservation length of the output beam is up to 50 mm. Practical significance. The developed algorithm for the synthesis of the optical system of the laser focal pi-Shaper uses a preset distribution of the radiation intensity on the input and output target surfaces. It can be used to design various laser beam-shapers forming intensity distribution profiles, which confirms its versatility.