皮肤反射式共聚焦显微成像扫描畸变校正

皮肤反射式共聚焦显微成像扫描畸变校正
刘创1,2，张运海1，黄维1,2，唐玉国1
(1.中国科学院苏州生物医学工程技术研究所江苏省医用光学重点实验室，江苏苏州215163；
2.中国科学院大学，北京100049)
摘
要:皮肤反射式共聚焦显微镜是一种重要的皮肤影像学诊断工具，其采用共振型振镜扫描成像会
带来非线性畸变，为校正这种畸变，提出一种像素值反正弦过采样信号重建的RCM 图像畸变校正方法，对间距为20μm 的矩形光栅扫描成像实验表明，在校正畸变前光栅图像间距的标准差为7.78μm ，图像的畸变率达到38.9%，经过像素值反正弦过采样信号重建后，光栅图像间距的标准差缩小为0.85μm ，畸变率缩小到4.2%。

结合分辨率板和实际人皮肤成像情况，表明文中提出的畸变校正方法能够较好地校正共振型振镜引起的图像畸变，满足人皮肤实时无创影像学诊断要求。

关键词:共聚焦显微镜；共振型振镜；非线性畸变中图分类号:TP391.4
文献标志码:A
DOI :10.3788/IRLA201847.1041003
Correction of reflectance confocal microscopy for skin imaging
distortion due to scan
Liu Chuang 1,2,Zhang Yunhai 1,Huang Wei 1,2,Tang Yuguo 1
(1.Jiangsu Key Laboratory of Medical Optics,Suzhou Institute of Biomedical Engineering and Technology,
Chinese Academy of Sciences,Suzhou 215163,China;
2.University of Chinese Academy of Sciences,Beijing 100049,China)
Abstract:Reflectance Confocal Microscopy for skin (RCM)is an important skin imaging diagnostic tool,which uses resonant galvanometer that will result in nonlinear distortion at image.In order to correct the distortion,a method of anti -sine signal oversampling based pixel using isochronous sampling system to correct the distorted RCM image caused by resonant galvanometer was presented.The results of experiments on the rectangular grating with a pitch of 20μm indicate that,the standard deviation of the grating spacing is 7.78μm.The distortion rate of image before being corrected is 38.9%.The standard deviation of the image corrected by the anti⁃sine signal over⁃sampling based pixel method is 0.85μm,so the distortion rate is reduced to 4.2%.According to the results of a resolution plate and the actual human skin imaging,the distortion correction method proposed in this paper can correct the image distortion caused by resonant galvanometer and meet the human skin real⁃time non⁃invasive imaging diagnostic requirements.Key words:confocal microscopy;
resonant galvanometer;nonlinear distortion
收稿日期:2018-05-05;
修订日期:2018-06-03
基金项目:(2017YFC0110303);(ZDYZ2013-1);(BK20160363);
(SYG201510);(SS201643)作者简介:(1992-),,,。

Email:patersonliu@ 导师简介:(1975-),,,,、(STED)、。

Email:zhangyh@
第47卷第10期红外与激光工程
2018年10月
Infrared and Laser Engineering
0引言
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1皮肤共聚焦成像系统的畸变产生与仿真。

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Method Arcsine over sampling
Distortion
4.2%
Before 38.9%
Sine [8]Curve fitting [8]10.7%
7.9%。