Development of femtosecond-laser-modulation technology based on spatial light modulators and its applications in the field of additive manufacturing

With the rapid advancements in science and technology, the field of micro/nano-manufacturing places higher demands on the fabrication precision and production efficiency of devices. Femtosecond laser technology, leveraging its unique advantages, including ultra-narrow pulse width, high peak power, and nonlinear absorption, has emerged as a core technique for high-precision micro/nano-fabrication. It demonstrates substantial potential in frontier fields such as micro-optical devices and biomedical engineering. However, the traditional point-by-point scanning method is limited by low efficiency, making it difficult to meet the requirements for high-throughput and cross-scale manufacturing. To address this, researchers have introduced light field modulation technology. By employing a spatial light modulator to manipulate the femtosecond laser's optical field, this approach enables the transformation of single-focus processing into multi-focus arrays, line focus processing, or plane field processing, significantly enhancing the fabrication efficiency of functional micro/nano-structures. This paper introduces the physical mechanism of femtosecond laser two-photon polymerization, elaborates on the research progress and applications of light field modulation technology, and outlines future research directions such as expanding the range of processable materials. This work serves as a reference for innovating light field modulation technology within femtosecond laser micro/nano-processing.