Large Field Of View Super-resolution Fluorescence Multimode Imaging Based On Micro-lens

Cell is the basic unit of higher life,which can reflect the state of living individuals.Collecting and analyzing cell profile and internal structure information is an important means of medical research,such as disease diagnosis and drug development.Fluorescence imaging,as an imaging technique using probe labeling,is currently the only way to obtain the internal structure information of cells.However,the drawbacks of the existing fluorescence imaging system greatly limit its application scenarios and cannot meet the needs of various detection in the limited experimental conditions.Therefore,it is quite vital to study a simple,convenient and costeffective fluorescence multimode imaging system.Based on the analysis of lensless fluorescence imaging system and traditional fluorescence microscope,a large-field fluorescence multi-mode imaging system based on micro-lens is proposed to solve the problems of the two kinds of fluorescence imaging systems.In order to theoretically study the feasibility and imaging quality of the fluorescence imaging system in this paper,firstly,the imaging principle and optical path model of fluorescence microscope and lensless fluorescence imaging system were analyzed.After considering the system characteristics of image sensor,such as the frame area,pixel size and sample characteristics,combining the advantages of the two kinds of existing systems,the optical path structure model and the mathematical model of single frame fluorescence image are established,and the factors affecting the quality of fluorescence image are discussed.Secondly,according to the optical path structure of the system and the requirement of expanding the imaging field of view,a two-dimensional scanning imaging model for panoramic fluorescence images was established,and the scanning trajectory was analyzed according to the application background of the system,for obtaining a better scanning imaging mode.In addition,according to the characteristics of the micro-lens fluorescence imaging system,two kinds of optimization and reconstruction algorithms for panoramic cell fluorescence images are proposed and discussed.Based on the above model,a large-field fluorescence imaging system of micro-lens based on two-dimensional mobile platform was built in this paper,a configurable multi-mode imaging lens and a micro-darkroom were designed,a collection experiment of single frame fluorescence images and large-field multi-frame fluorescence images was completed,and the registration experiment of the acquired multi-frame fluorescence images was carried out by using the optimization reconstruction algorithm proposed in this paper.Then the reconstructed panoramic fluorescence images were processed with super resolution to further improve the image resolution.Finally,the integration of the control and drive circuit of the two-dimensional mobile platform is designed and realized based on the single chip microcomputer.At the same time,the miniaturization scheme of the large-field fluorescence multi-mode imaging system of the micro-lens is given.The device size is 108×108×156mm3.The results of two imaging experiments of 20μm fluorescence microspheres show that the optical path model of the micro-lens fluorescence imaging system has the correct structure and can accurately reflect the real information of the samples.The average error of the diameter of the microsphere in the fluorescence images collected by the system is only 5.16%.The imaging resolution of 1.34μm in～193mm2 can be obtained by expanding the field of view with two-dimensional scanning imaging.The experimental results of panoramic fluorescence image reconstruction show that the proposed algorithm based on SURF feature points can effectively solve the registration failure problem caused by high mismatching rate.The average registration rate is 23.46%,about 6.4 times that of traditional SURF matching algorithm.The binary template fast matching algorithm based on the improved search strategy also greatly improves the matching efficiency.Its registration time is only 20.14%of the mean value of the traditional template matching algorithm,and it is easier to implement in hardware.Therefore,the large field super resolution fluorescence multi-mode imaging system based on micro-lens is feasible and simple.The proposed optimization and reconstruction algorithm for panoramic cell fluorescence images has high efficiency.