Randomized metalens array homogenizer for enhanced laser beam shaping

Abstract

We present a beam homogenizer utilizing on a random metalens array (RMA) for enhanced beam shaping. The RMA, comprising 28 × 28 individual metalenses with random sizes, is designed using an improved Gerchberg-Saxton algorithm. As a laser beam traverses the RMA, it is divided into 28 × 28 beams, each exhibiting a unique speckle pattern. These beams overlap in the far field, significantly enhancing beam uniformity. The RMA demonstrates adaptability to various incident light modes and misalignment variations. The numerical simulations indicate over 90% uniformity in the shaped beams, while in experimental results show a reshaped line beam achieving 95.9% uniformity. This beam homogenizer has potential applications in minimizing the size of LiDAR systems or laser engraving systems, offering broader utility across these fields.