共路剪切数字全息自参考聚焦显微成像  

Self-reference focusing imaging for common-path shearing digital holographic microscopy

作　　者：黄琳琳 刘丙才[1] 王红军[1] 张雪灵 张萍[1] 张瑞轩 田爱玲[1] HUANG Linlin;LIU Bingcai;WANG Hongjun;ZHANG Xueling;ZHANG Ping;ZHANG Ruixuan;TIAN Ailing(Shaanxi Province Key Laboratory of Thin films Technology and Optical Test,Xi'an Technological University,Xi’an 710021,China)

机构地区：[1]西安工业大学陕西省薄膜技术与光学检测重点实验室,陕西西安710021

出　　处：《光学精密工程》2024年第23期3416-3423,共8页Optics and Precision Engineering

基　　金：陕西省科技厅资助项目(No.2023-YBGY-136);陕西省教育厅资助项目(No.23JY034)。

摘　　要：提出了一种基于共路剪切的数字全息自参考聚焦显微成像方法。该方法利用偏振光栅的分光特性,设置了双偏振光栅的剪切装置,并实现了对携带样品信息的物光复制。通过调节双偏振光栅之间的距离,灵活控制相机上显微像和全息干涉像之间的距离,实现了显微像和全息干涉像的同时记录。在显微像和全息干涉像同时记录的基础上,记录多幅离焦-聚焦-离焦图像,再利用Brenner梯度法对相机记录的多幅离焦-聚焦-离焦图像中的显微成像区域进行聚焦评价,找出最佳聚焦图像,完成自参考聚焦。同时,采用角谱法对最佳聚焦图像中的干涉区域进行相位重建。最后,以相位分辨率板作为实验样品来验证所提方法的可行性。实验结果表明:相位分辨率板的高度为0.336μm,平均绝对误差为0.023μm,所提方法具有准确性高、稳定性好以及结构紧凑等优点。This paper presents a self-reference focusing digital holographic microscopy method based on common-path shearing.The method employs a dual-polarization grating shearing device that utilizes the polarization grating’s spectral properties to replicate the object wave carrying sample information.By adjusting the distance between the dual-polarization gratings,the spacing between the micrograph and the holographic interference image on the camera can be flexibly controlled,enabling simultaneous recording of both.Through recording multiple images from defocus to focus to defocus,the Brenner gradient method is applied to determine the optimal focus,achieving self-reference focusing.The ASM is then used to reconstruct the interference region’s phase at the best focus.Experimental verification,using a phase resolution plate,demonstrated a measured phase height of 0.336μm with an average absolute error of 0.023μm.The proposed method features high accuracy,stability,and a compact design.

关 键 词：数字全息 显微成像 自参考聚焦 共路剪切 

分 类 号：O438.1[机械工程—光学工程]