快速并行激光显微切割方法

A rapid parallel laser microdissection method

针对传统激光显微切割采用单激光焦点与工件相对运动形成加工轨迹,存在切割效率低、切割轨迹首尾不易闭合等局限性,提出基于数字微镜器件的无机械运动激光显微切割方法。通过调控数字微镜阵列,对激光光束的振幅进行调控,配合光路设计在样品区域得到任意的光场强度分布,实现强度近乎相同的面投影并行切割。阐述了关键参数设计、模拟仿真、系统搭建过程。先对聚酯薄膜进行直线、空心圆环、空心矩形等多种图案的切割,再对冷冻切片的细胞组织进行切割。实验表明,通过一次投影并行切割可设计的图案化结构,目标图形准确,切割效率高。在20×物镜下,最小切割线宽达到亚微米,最小圆环直径小于单细胞直径。该方法可为提高激光显微切割系统的效率和精度提供新思路和新方向。

With regard to the traditional laser microdissection using the relative motion between the single laser focus and the workpiece,there are limitations in forming the machining trajectory,such as the low cutting efficiency and the difficulty in closing the cutting trajectory.To address these issues,a laser microdissection method based on digital micromirror device without mechanical movement is proposed.By adjusting the digital micromirror array,the amplitude of the laser beam can be adjusted,and the arbitrary light field intensity distribution can be obtained in the sample area with the optical path design.In this way,the parallel cutting of plane projection is realized with almost the same intensity.Meanwhile,the process of key parameter design,simulation,and system construction is described.Specifically,the polyester film is first cut with various patterns such as straight line,hollow ring and hollow rectangle.Then,the frozen section of cell tissue is cut.Experiments show that,by one projection,designable patterned structures can be cut in parallel with accurate target graphics and high cutting efficiency.Under the 20×objective lens,the minimum cutting line width reaches sub-micron,and the minimum ring diameter is smaller than the single cell diameter.This method can provide new ideas and new directions for improving the efficiency and accuracy of the laser microdissection system.