High-Fidelity Micro-Pattern Printing Based on Non-Uniform Sampling Holographic Femtosecond Laser

Holographic femtosecond laser printing has been widely used for the fabrication of micro-patterned structures owing to its high efficiency and flexibility. However, conventional pixel-based patterns rely on high-density uniform sampling, which imposes limits on pattern fidelity and computational efficiency. In this work, a high-fidelity micro-pattern printing method is proposed based on a non-uniform sampling holographic femtosecond laser. Precise control of pattern contours is achieved at a low global sampling number by performing local non-uniform sampling, which is enabled by replacing the Fast Fourier Transform with a non-uniform matrix triple product formulation for diffraction calculation. In addition, an adaptive holographic field modulation strategy is established, where amplitude-weight compensation is introduced to address the diffraction imbalance arising from differences in sampling point area. Based on the method, vector-defined patterns generated from functional expressions and engineering drawings are fabricated with high fidelity. For a representative “B” pattern, the computational efficiency improves by ≈9.4 times compared with the uniform-sampling method, and the edge roughness is reduced from 330 to 120 nm. Finally, a millimeter-scale Fresnel zone plate is fabricated by splicing multiple non-uniform sampling holographic patterns, demonstrating the potential of the method for precision optical device manufacturing.