Design And Implementation Of An Multi-field Parallel Independent Focusing Array Microscopic Imaging Device

Microscopic imaging and pathological diagnosis of pathological samples are indispensable clinical testing methods.The digital pathology method based on slice digital imaging,transmission and analysis improves the work efficiency of pathologists.However,the current slice digital imaging usually uses large-scale digital scanners based on traditional microscope objectives and microscopic imaging systems,and slice digitalization is usually concentrated in the pathology department or inspection center of the hospital.With the advancement of imaging devices and mobile phone performance,researchers are also trying to use mobile phones as imaging platforms,plus a low-cost microscope or microscope head,to achieve a more inexpensive and miniaturized microscopic imaging device,hope to be able to conduct digital sample collection in grassroots communities and even families.In order to improve imaging throughput,there is also a method using a micro lens array,multiple areas of the sample are imaged in parallel with a fixed focal length.In response to the needs of small portable microscopy imaging,based on a dedicated image processing chip,this paper designs a multi-imaging unit array microscopy imaging scheme with independent focus adjustment and further expansion of the imaging unit,which realizes a small and low-cost array microscopic imaging device,demonstrates its application in slice imaging.The main tasks include:(1)This paper designs an array microscopic imaging scheme with multiple microscopic imaging units.Image acquisition adopts a modular approach,and each image acquisition module is composed of an image acquisition board and two microscopic imaging units,which can acquire images of two channels in parallel.Multiple image acquisition modules can be cascaded and synchronized for image acquisition.The image acquisition board using a dedicated image processing chip can control the imaging hardware more flexibly and realize the automatic focusing of the imaging unit by calling the image contrast statistical function.Using miniature image sensor and miniature lens module to assemble into a microscopic imaging unit,the imaging field of view is 3.4mm×2.5 mm,and the resolution is 2 μm.Using the voice coil motor to drive the micro lens,multiple microscopic imaging units can be independently adjusted to focus,so as to adapt to focal plane fluctuations caused by changes in sample thickness at different positions.(2)Taking a 2×2 array as an example,an array microscopic imaging device composed of four microscopic imaging units is realized.The sample is moved by the self-designed electric translation stage,and the focal plane fitting method is adopted to realize the rapid auto-focusing of each area.The microscopic imaging of the circular sample area with a diameter of 20 mm can be completed in about 2 minutes,and the imaging effect is close to that of a conventional microscope’s 10×/0.25 NA objective lens.The overall size of the imaging device is 125 mm × 85 mm × 73 mm.The array microscopic imaging device designed in this paper is expandable and cropped in hardware and software.By cascading more image acquisition modules,it can quickly acquire microscopic images of samples with a larger area and can also dynamic imaging of multiple samples.The research in this article provides a feasible and fast imaging solution for micron-resolved large samples or multi-sample microscopic imaging.