Design And Implementation Of Iris Image Acquisition System Based On FPGA

Iridology is a kind of medical diagnosis assistant technology.By analyzing detailed structure of iris variation in human body,diagnosis of related diseases can be achieved.Effective acquisition of iris image is premise of further diagnosis.According to request of iris diagnosis for iris image acquisition,aiming at high-speed characteristic of FPGA in image acquisition and processing,this paper designs an iris image acquisition system based on FPGA.Function of collecting and transmitting iris image data is realized.Main work of this paper is as follows:1.Design of system hardware.It is made up of FPGA core circuit,SDRAM data buffer circuit,USB2.0 interface circuit,VGA driver circuit,power circuit,GPIO interface circuit and other related circuits.Optical assistant module is designed.After circuit design is finished,relative parameters are obtained by calculation of stack and impedance.Reasonable layout and wiring of system PCB are carried out,and reference plane of power supply is divided.Integrity of key signals is analyzed.Finally,welding of circuit board is completed.2.Design of system logic and software.It includes design of image acquisition module,logical design of color image restoration using interpolation algorithm,controller design of image buffer module SDRAM,USB 2.0 interface and firmware design and VGA display module driver design.3.Debugging and testing of the system.Hardware test includes testing output voltage,ripple voltage and crystal oscillator waveform of system power supply.Logic part includes analysis of sample data waveform of each module.USB2.0 transmission speed is simulated and tested.Finally,function of system is tested and collected images that fully meet needs of iris diagnosis.