Microscopic Imaging System Based On FPGA Controlled Programmable LED Array

As a general observation and measurement instrument,optical microscopes have long been infiltrated into all works of life around us.It is the "materialization judge" of today's society,but also a "key to explore the micro-world",it can be said throughout the "eat and wear and use,agriculture and light and heavy industry,sea and land and air".However,with the continuous innovation of function and performance,the current microscope system has three major problems which become increasingly prominent:rely on dyeing and marking and other invasive methods to imaging;it is difficult to take both resolution and field size into account;the system is increasingly expensive,cumbersome,complex and difficult to maintain The no mark,high resolution,large field of view,easy operation,low cost is the goal of optical microscopy that developing so far.In this paper,a micrographic imaging system based on FPGA which controls programmable LED array.Unlike the traditional microscopes which use fixed illumination,the system uses a programmable LED array as an illumination source,which gives the ability of flexible and adjustable to the microscope's illumination aperture,illumination angle and light source coherence.In this paper,the following work is done:Firstly,the optical system is built by using programmable LED array,and you can achieve multi-mode imaging by changing the radius or the position of center of the light source.Secondly,the algorithm of bright field,dark field,differential phase contrast and light field imaging is designed and then draw the imaging flow chart.Thirdly,I select the FPGA and other chips by the chip manual and design the hardware circuit,and then draw the PCB board,and design program to drive and lit the programmable LED array,thus you can control the illumination source accurately.Fourthly,design the software system,it is much more convenient and intuitive for users to control of the entire system.Finally,built the whole system and use different magnification objective lens and samples to realize four kinds of microscopic imaging methods.Analyze the experimental results and propose improvement methods of the system.The experimental results show that the system is simple in structure and easy to operate,it don't need any special microscopic objective lens to realize the microscopic functions of bright field,dark field and differential phase contrast.In addition,it achieves a high-resolution multi-angle light field imaging by using the programmable LED array without any loss of spatial resolution.Compared with the traditional micro-system which can only provide a single front view,the system can realize a flexible control of the imaging perspective,that the samples can be viewed and tested by multiple perspectives from the three-dimensional space,this feature gives the traditional microscope additional degrees of freedom.The observer can change the radius and center of the LED illumination source according to its own requirements and select an imaging mode to achieve the direct observation of the samples to be measured..