Hardware System Design Of Multispectral Fundus Imager Based On FPGA

With the development of optoelectronic technology and the advancement of medical equipment,new technologies are constantly being applied to actual surgery.In the field of retinal imaging,the transformation from the earliest ophthalmoscope to the more convenient fundus camera technology was realized.However,traditional fundus cameras have great limitations due to their simple functions,and screening for many eye diseases cannot provide accurate information.Therefore,this paper relates to a fully automatic multi-spectral fundus layered camera.Multi-spectral fundus layered imaging has the advantage of acquiring tissue images at different depths of the fundus,and many diseases such as retinopathy of prematurity and diabetic complications can occur in different depths of the fundus,thus obtaining multispectral The fundus layered image can detect the condition earlier and provide a medical basis to avoid missing the best treatment time.The paper focuses on the control system design and circuit design of the fully automatic multi-spectral fundus layered camera,including LED control module and HDMI to LVDS signal switching module.The LED timing control module includes peripheral circuits required for normal operation of the FPGA,interface circuits for communication between the computer and the FPGA,I/O port circuits of the FPGA,level conversion circuits,FPGA signal enhancement circuits,and high-power LED drive circuits.The HDMI to LVDS signal switching module mainly includes an HDMI interface circuit,an HDMI receiving circuit and an LVDS interface circuit.The device selection and characteristics of each functional circuit are introduced in detail,and the circuit schematic and PCB design of the two control modules are completed.The paper designs the FPGA program for the two control modules designed,and adds the logic design module to realize the functional requirements.The two modules in this article are primarily implemented in the PL(FPGA Logic)portion of the FPGA using the Verilog language.The FPGA program design of the LED control module mainly includes the system clock module,the button detection and debounce module and the LED timing control module.HDMI to LVDS conversion module programming mainly includes HDMI acquisition chip ADV7611 acquisition PC data debugging and LVDS LCD driver display.The paper carried out a variety of test experiments on the FPGA development board and program designed and produced.The test results show that the development boards of the two control modules are functioning properly and are connected to each other correctly.Each module can work in coordination and can complete the task of system delivery.