Li Yupeng, Li Yifan
College of Metrology Measurement and Instrument, China Jiliang University, Hangzhou 310018, China.
Sensors (Basel). 2025 Apr 21;25(8):2620. doi: 10.3390/s25082620.
Micro-nano measurement represents a critical engineering focus in the advancement of micro-nano fabrication technologies. Exploring advanced micro-nano measurement methods is a key direction for driving progress in micro-nano manufacturing. This study proposes a confocal measurement method utilizing a liquid crystal spatial light modulator (LC-SLM) to simulate a binary Fresnel lens for 3D focusing, enabling the non-mechanical measurement of spatial positions on sample surfaces. Specifically, it introduces a 3D focusing method based on LC-SLM, constructs a confocal microscopy 3D focusing system, and conducts lateral focusing experiments and axial focusing experiments. Experimental results demonstrate that the system can freely adjust lateral focusing positions. Within an axial focusing range of 900 μm, it achieves axial measurement accuracy exceeding 1 μm, with a maximum resolution capability of approximately 16.667 nm. Compared to similar confocal microscopy systems, this method allows rapid adjustment of lateral focusing positions without regenerating phase grayscale maps, achieves comparable axial measurement accuracy, and enhances measurement speed.
微纳测量是微纳制造技术发展中的一个关键工程重点。探索先进的微纳测量方法是推动微纳制造进步的关键方向。本研究提出一种利用液晶空间光调制器（LC-SLM）模拟二元菲涅尔透镜进行三维聚焦的共焦测量方法，实现对样品表面空间位置的非机械测量。具体而言，介绍了基于LC-SLM的三维聚焦方法，构建了共焦显微镜三维聚焦系统，并进行了横向聚焦实验和轴向聚焦实验。实验结果表明，该系统能够自由调节横向聚焦位置。在900μm的轴向聚焦范围内，轴向测量精度超过1μm，最大分辨率能力约为16.667nm。与类似的共焦显微镜系统相比，该方法无需重新生成相位灰度图即可快速调节横向聚焦位置，轴向测量精度相当，且提高了测量速度。
