Multi-focal laser processing in transparent materials using an ultrafast tunable acoustic lens

Fast and versatile alteration of focal positions is critical for applications including selective volumetric modification and parallel laser processing. In this Letter, we implement and characterize an ultrafast, variable focal system using a tunable acoustic gradient of index lens to achieve multi-focal laser processing. We apply our method to the femtosecond laser-induced intra-volumetric modification in glass to show the flexibility in controlling focal positions. Based on this understanding, we exploit the multi-focal nature of the system to demonstrate laser machining on both surfaces of a transparent glass slide in a single lateral scan. (C) 2022 Optica Publishing Group

Automated summary

In this Letter, the authors introduce a fast and versatile variable focal system using a tunable acoustic gradient of index lens for multi-focal laser processing. They demonstrate its application in femtosecond laser-induced volumetric modification in glass and laser machining on both surfaces of a transparent glass slide.