全自动推扫式高光谱显微成像系统设计与研究

Design and research of fully automatic push-broom hyperspectral microscopic imaging system

为了将光谱成像技术更方便地引入显微成像领域,本文将高光谱成像技术与显微成像技术相结合,搭建出一套全自动推扫式高光谱显微成像系统。系统以倒置显微镜为主体进行设计,采用棱镜-光栅元件进行光谱分光,利用高精度二维电动运动平台进行推扫,同时结合电动对焦组件完成对焦,最后成像在高灵敏sCMOS科学相机上。根据大多数生物样本光谱检测需求,系统的光谱范围选择420~800 nm。经光谱定标和空间分辨率测试,确定系统的光谱采样率为2.06 nm,光谱分辨率均值优于3.5 nm,空间分辨率优于0.87μm。系统引入激光自动对焦系统作为主动对焦模块,以HE染色的乳腺癌病理切片为研究对象,实验分别采用被动对焦和主动对焦方式进行推扫成像,并比较分析两种方式的优劣,认为两者均可以满足大视场成像需求,但主动对焦成像更快速、更清晰,更加适合推扫式高光谱显微成像系统。通过对全自动推扫式高光谱显微成像系统的设计与研究,解决了高光谱显微成像中无法实时对焦的难题,实现了40倍显微物镜下3.25 mm×3.25 mm范围内全自动成像,有利于促进光谱技术在生物医学等领域中的应用。

To apply hyperspectral technology to the field of microscopic imaging more conveniently,we de-signed and built a fully automatic push-broom hyperspectral microscopic imaging system.In this system,an inverted microscope was designed as the main body,a prism-grating component was used for spectrum split-ting,a high precision two-dimensional motorized stage was applied for a push-broom.A motor focus module was used to control the focus,and a hyperspectral microscopic image was collected through a highly sensit-ive sCMOS scientific camera.The system has the advantages of low cost,easy installation and adjustment,real-time focusing and large-field-of-view imaging.The spectral range of the system is from 420 nm to 800 nm to meet the spectrum detection requirements of most biological samples.The spectral resolution was better than 3.5 nm,and the spatial resolution was better than 0.87μm through the monochromatic collim-ated light scanning calibration method.Then,the HE-stained breast cancer pathological slices was as the re-search object.The samples were investigated and compared using passive and active focusing for push-broom imaging.The advantages and disadvantages of the two focusing methods were analyzed and summar-ized.The results showed that both methods can meet the needs of large-field-of-view imaging,but active fo-cus imaging is faster and clearer,and is more suitable for push-broom hyperspectral microscopy imaging sys-tems.Through the design and research of a fully automatic push-broom hyperspectral microscopy imaging system,real-time focusing in hyperspectral microscopic imaging was realized and 3.25 mm×3.25 mm field of view imaging of biological samples with a 40X objective lens was achieved.This system could be beneficial for promoting the application of hyperspectral technology in the biomedical field.