Sheng Zhong, Wang Yun, Zhao Weiqian, Qiu Lirong, Sun Yingbin
Appl Opt. 2016 Sep 1;55(25):6903-9. doi: 10.1364/AO.55.006903.
Based on the optical arrangement of a bipolar differential confocal microscopy (BDCM), laser differential fitting confocal microscopy (DFCM) is proposed in this paper using the feature of BDCM that a zero-crossing point (ZCP) of the axial response curve precisely corresponds to the focus of the system objective. A linear segment of the DFCM axial response around the ZCP is used to fit a straight line. Focus can be determined by solving the equations of the fitting lines, and then, the sample surface could be measured and reconstructed with a high resolution. Compared with the curve-fitting peak detection, which is an algorithm for focus detection widely used in conventional confocal microscopy, the line-fitting zero solution method used in DFCM has several advantages, such as high precision and sensitivity. Most importantly, precise focus detection can be realized using less data, i.e., DFCM has a high measurement efficiency. Furthermore, DFCM can effectively eliminate common-mode noise in a confocal microscopy system and has good noise suppression and disturbance resistance capability.
基于双极差分共聚焦显微镜（BDCM）的光学配置，本文提出了激光差分拟合共聚焦显微镜（DFCM），利用BDCM的轴向响应曲线的过零点（ZCP）精确对应于系统物镜焦点的特性。DFCM轴向响应在ZCP附近的线性段用于拟合一条直线。通过求解拟合线的方程可以确定焦点，然后，可以高分辨率地测量和重建样品表面。与传统共聚焦显微镜中广泛使用的用于焦点检测的曲线拟合峰值检测算法相比，DFCM中使用的线拟合零解方法具有高精度和高灵敏度等优点。最重要的是，使用较少的数据即可实现精确的焦点检测，即DFCM具有较高的测量效率。此外，DFCM可以有效消除共聚焦显微镜系统中的共模噪声，具有良好的噪声抑制和抗干扰能力。
