Beam Shaping System based on Polymer Spherical Gradient Refractive Index Lenses

摘要

A two-element laser beam shaping system based on spherical gradient refractive index (GRIN) lenses has been designed utilizing the optical design package CODE V®. The impetus for this design is the recent development of large diameter (~ 20 mm) layered polymer spherical GRIN lenses that can be fabricated with arbitrary index of refraction profiles between 1.490 and 1.573. A merit function is developed that includes the index range constraint, radius of curvature and thickness fabrication constraints, and a mapping function which maps the Gaussian irradiance profile into a flat-top profile. The designed system features high transmission efficiency, with nearly 100% of the energy transferred to the output beam and a variance of less than 3% in uniformity from the center to the edge of the beam. The adaptability of the lens making process allows for an additional degree of freedom in beam shaping.