Research On Super-resolution Imaging System With Lensless Using Dual-line Array Image Sensor

The acquisition of biological cell images is an important means in pathological analysis,disease diagnosis,health monitoring and drug development.In community medicine,telemedicine and other real-time diagnosis,cell image acquisition equipment with lensless imaging technology is more conducive to promotion and popularization because of its miniaturization and low cost.However,compared with microscope,its spatial resolution is still low,so it is of great significance to study the super-resolution imaging system of lensless imaging technology.In this paper,aiming at the problems of single line array super-resolution scanning imaging,,a super-resolution scanning imaging method using dual-line array image sensor for real-time measurement of cell flow velocity is proposed.In order to study the performance of the super-resolution scanning imaging system of the dual-line array image sensor theoretically,the scanning imaging model of dual-line array super-resolution imaging method is established firstly by comprehensively considering the characteristics of the light source,diffraction light path,pixel size of the image sensor,frame rate,cell sample flow rate,etc.,and the factors affecting the imaging quality of the dual line array are deeply analyzed.Secondly,the reconstruction model of the dual-line array scanning image is established.Combined with the scanning imaging model,the influence factors and characteristics of the imaging are analyzed based on theoretical simulation,and the models are optimized according to the simulation results.Then,combined with the characteristics of dual-line array super-resolution imaging,the diffraction recovery algorithm based on angular spectrum theory is improved.Based on the above model,a dual line array super-resolution cell scanning image acquisition system is built,a two-dimensional focused microfluidic chip is designed,and the acquisition experiments of microspheres,red blood cells and white blood cells are completed.The super-resolution reconstruction of the collected image data is carried out by using the scanning image reconstruction model.Aiming at the phenomenon of uneven cell velocity caused by fluid disturbance during sample flow,the reconstruction algorithm of scanning image is improved by calculating the instantaneous velocity of cells flowing through the linear array,and the imaging effect is improved.Finally,a dual-line array super-resolution imaging system is designed and implemented based on the embedded system,in which the size of the miniaturized acquisition device is 49.40×49.40×78.55mm3.The simulation results of circular and striped patterns show that the spatial resolution of the dual-line array super-resolution imaging system is at least 2.8 times higher than that of the area array system.Meanwhile,the structural similarity and peak signal-to-noise ratio are both improved by 5%-15%The test results of microspheres,red blood cells and white blood cells show that the microsphere diameter error of the dual-line array super-resolution imaging system is only 2.04%,compared with the area array imaging system,and the cell features are more and more obvious.Therefore,the lensless super-resolution imaging system using the dual-line array image sensor in this paper is feasible,effective and accurate.