Parallel beam splitting and controlling system based on cascaded acousto-optic modulators

Abstract

In recent years, ultrashort pulse lasers (lasers) have been already widely used for providing excellent laser machining quality for the electronics industry, replication tools, and other applications. However, the major drawback of this processing is low efficiency, especially for a large number of laser ablation demands. In this paper, a beam-splitting approach based on cascaded acousto-optic modulators (AOMs) is proposed and analyzed in detail. The cascaded AOMs can split a laser beam into several beamlets with the same propagation direction. These beamlets can be switched on and off individually, and the beam pitch can be changed independently. At the same time, the experimental setup of three cascaded AOM beam splittings is built up to verify the capability of the high-speed control (switching rate:1 MHz), high-energy utilization rate (>96% at three AOMs), and high-energy splitting uniformity (nonuniformity: 3.3%). This scalable approach enables the processing of arbitrary surface structures with high quality and efficiency.