建立全场光学相干层析系统(OCT),可对生物细胞进行高分辨率层析成像。该系统基于Linnik干涉结构,采用低相干白光光源卤钨灯照明和大数值孔径的显微物镜,理论分辨率可达0.7μm×0.7μm(横向×轴向)。系统采用电荷耦合元件(CCD)采集数张样品和参考镜的干涉图,通过三步移相算法获取层析图,最后合成三维图像。与荧光标记细胞等其他生物组织成像的方法相比,全场OCT成本低廉、对细胞无损伤、分辨率高。该系统能够完成对洋葱表皮细胞和猪肝组织切片细胞等生物组织实现层析成像,且分辨率高、成本低、结构简单便于调节,为实现高分辨率光学相干层析成像提供了简单易行的方法。
Aninterference microscope for ultrahigh-resolution full-field optical coherence tomography (FFOCT) system was developed for imaging of biological media. The experimental setup is based on a Linnik-type interferometer illuminated by a low coherence tungsten halogen lamp and equipped with high numerical aperture microscope objectives. The theoretical resolution of the system is 0.7μm×0.7μm(lateral×axial). En-faee tomographie images were obtained by a combination of interferometric images recorded by a smart CCD camera and 3-step phase-shifting algorithm. Previous studies usually used 4-step phase-shifting algorithm with less speed of shifting the phase. Three-dimensional images can then be generated from these tomographic images. Compared with fluorescence labeling image, FFOCT has advantages of low cost, no damage, and ultrahighresolution. En-faee images of onion surface cellsand liver biopsy tissue cells showed the excellent performance of the system for generating en-face images of biological tissues. Our system is characterized by its high resolution, low cost and simple arrangement for adjustment, providing a practical method for FFOCT imaging.