Research On The Detection Technology Of Lensless On-chip In-line Holographic Imaging

With the continuous development of modern medical technology,biomedical testing equipment is developing towards miniaturization and portability.As an emerging technology,lensless on-chip detection technology is widely used.Small size,low price,easy to operate and other advantages make the biological miniaturization detection equipment using lensless detection technology suitable for application in poor or remote areas.To improve the low-resolution characteristics of traditional lensless shadow imaging systems and to meet the high-resolution needs of point-of-care testing(POCT),this paper studies and designs a new miniaturized detection platform based on in-line holographic imaging detection technology.Under the condition of fully verifying the imaging resolution of the system,holographic imaging of biological particles and cell smears is carried out.After that,the phase of the holographic image was reconstructed on the personal computer(PC),and the application of cell identification and counting(CIC)was realized.The United States Air Force(USAF)resolution test board was used to test the resolution performance of the lensless holographic imaging detection platform,and compared with the traditional lensless shadow imaging platform and optical microscope platform,the resolution of the holographic imaging platform was higher than that of the shadow imaging platform.The resolution is increased by 1.59 times,which is the same as the high-definition contrast image taken by a ×10 microscope.Take 15μm polystyrene microspheres and mouse ascites tumor cell mixed solution smears,after the phase recovery is achieved through the iterative phase recovery(IPR)algorithm,the cells and particles contained in the image are identified and counted using the machine learning-based cell segmentation recognition and automatic cell counting methods,and the results showed that this platform can realize high-precision biological applications of counting cells,which is consistent with the number of cells in the manual counting microscope image.This lensless holographic imaging detection platform has the ability to detect,identify and count various biological cells including blood cells with high accuracy.As a basic medical detection application,it lays the foundation for the development of miniaturized and portable POCT equipment.It has the prospect of being applied in remote areas and epidemic areas.