Many applications utilizing lasers require shaping of the laser into a thin flat top line with good uniformity, especially in fields such as microscopy, wafer inspection and laser lift off. Often, multimode lasers are used, due to their lower cost per watt compared to single mode lasers, requiring shaping that is based on diffusers and lens arrays.

In the PhotonicsViews article, the authors present a method for improving the narrow-axis integrated intensity uniformity in laser line beam shaping for partially coherent laser sources. The proposed approach involves utilizing a tailored anamorphic diffuser (TAD) to create a controlled mixing of the coherence in both line dimensions, enabling improved uniformity. This method is compared to existing solutions for specific examples. Furthermore, the article addresses the manufacturing feasibility of the proposed method, highlighting potential fabrication techniques and their practicality.

The comparative analysis demonstrated the advantage of the proposed diffuser. The TAD offers enhanced control over intensity distribution, enabling uniform laser line profile, by considering specific laser beam quality factor value. This theoretical improvement was observed in real experimental result of double sided lens arrays incorporating TAD which showed an integrated intensity profile that has a significantly improved uniformity (peak to average ~15 %) compared to a standard double sided lens array.

The findings of this study open up new possibilities for the development of high-performance laser systems with enhanced precision and efficiency in a wide range of applications, including laser lift-off, laser inspection and detection, and biomedical imaging applications.

Read the interactive issue in the Adobe Cloud, or download the PDF – Alexander Brodsky, Natan Kaplan, and Tamir Amrani (all: Holo/Or): Line beam shaping with a tailored anamorphic diffuser, PhotonicsViews, E-Special 1, 2025, published 23 January 2025