Based On The Linear Array Ccd Image Detection System

OLED(Organic Light Emitting Display) is one of the most prospective panel display in the future because it has many advantages, such as light quality, thin thickness, high contrast, fast response and actively light emitting. But the point, line, plane defects will unavoidably exist dueing to the fabricating technology and circuit structure and so on. And these will make the observer uncomfortable when he or she looks at the panel. At present, most of the inspections have been done by the experienced inspectors according to the sample. This way will add subjective factors unavoidably. The related reports about defect inspection system applied to OLED panel are very few, so it is very important to develop OLED defect inspection system.According to the defects of OLED panel, the OLED defect inspection system has been designed. This system composes of the front-end image acquisition and the back-end image processing. Firstly, the dissertation gives the whole block diagram and every part of the system, introducing the function and application of the linear CCD(Charge-coupled Device)TCD1705 produced by TOSHIBA company, the image and video processing A/D(Analog/Digital convert) chip VSP2212 produced by TI company, the FIFO(First Input First Output) chip IDT72225 produced by TI company, and PCI (Peripheral Component Interconnect) interface chip PCI9054 produced by PLX company. Secondly, the circuits are given and simulated. The PCB(Printed Circuit Board) is drawn with Protel99 SE software and debugged. The image acquisition hardware system mainly composes of three parts: the CPLD (Complex Programmable Logic Device)development board, the image acquisition board and the PCI image transmission board. The programs are tested and the images are acquired based on the CPLD development board and the image acquisition board, and the local bus communicates with the PC based on the PCI image transmission board.The CPLD chip EPM7128 produced by ALTERA company is chosen as the controller. First the CPLD chip controls the stepping motor location and scanning, and drives CCD to work. And then the analog signal of CCD output is converted into digital signal by A/D chip. The digital signal is transmitted into FIFO buffer. At last, the system communicates with PC. Internal control logic is designed with Verilog language (Hardware Description Language). Its functional simulation is done by Quartus7.0 and CPLD is filled successfully.The hardware system is detected by the computer, and then the driving program is developed on WinDrive software. At last the application program is developed with VC++ 6.0 and the image has been processed on MATLAB software ( Matrix Laboratory).