激光共焦显微光束的偏转扫描

Beam deflection scanning for laser confocal microscopy

为了提高激光共聚焦系统的扫描速度,本文提出一种逐场扫描的场同步扫描方法。构建了激光共焦显微系统,将美国THORLABS公司的GVS002型二维检流计振镜应用于该系统,根据光学系统参数以及扫描范围要求计算振镜的整场扫描波形。借助NI公司的PCIe6353多功能数据采集卡,输出行同步的扫描波形,同时,对共焦显微系统共焦位置上针孔处的光强信号进行采集,先后扫描一幅256×256和512×512的图像,记录扫描图像和成像时间;然后,在相同的硬件结构下,以场同步的方式输出扫描波形,记录扫描图像和成像时间。实验结果表明:场同步方式扫描256×256图像的速度可提高10倍,扫描512×512图像的速度可提高5倍,且满足共焦显微成像的清晰、抗干扰能力强等要求。与行同步扫描方法相比,场同步扫描方法可以消除行与行之间转换的停留时间,在不改变硬件的情况下大幅提高扫描速度。

To improve the scanning speed of the laser confocal system,a field synchronous scanning method was proposed.The laser confocal microscopy system was implemented with a GVS002 two-dimensional galvanometer from the THORLABS Company.The scanning waveforms of galvanometer were calculated in accordance with the parameters and scanning range of the optical system.The synchronous scanning waveform was output from a PCIe6353 multi-functional data acquisition card of NI Company.Meanwhile,it collected the optical intensity signals at the pinhole at the focus of the confocal microscopy system and scans a 256×256 image and a 512×512 image successively,recording the scanning images and imaging time;then,the scanning waveforms were output in field synchronization under the same hardware structures,recording the scanning images and imaging time.The experimental results show that the speed of the 256×256 image scanning through field synchronization can be increased by 10 times and the speed of the 512×512 image scanning can be increased by 5 times.In addition the field synchronous scanning can meet such requirements of the confocal microscopy imaging as the clearness and strong capacity of resisting disturbance.Compared with the line synchronization scanning,the field synchronous scanning can eliminate the retention time during the line to line conversion and significantly improve the scanning speed without changing the hardware.