Optical Microscopy Pattern Measurement System Based On The Camera Link Interface, The Image Acquisition Card Design

Optical Microscope Pattern Measuring System is a kind of machine vision system which contains optical system, CCD, image acquisition technology, digital image processing and software technology. The line width, line separation and hole diameter on the PCB can be detected accurately; the disadvantages brought by the traditional methods are overcomed; the precision, resolution, efficiency of manufacturing are improved; cost of the production is decreased.Optical Microscope Pattern Measuring System is composed of light source, lens, CCD camera, image acquisition card and computer. This dissertation developes an image acquisition system using Camera Link, DDR SDRAM, FPGA and PCI BUS. Digital signal from CCD camera can be imported into this system directly. The speed of data transmission and the anti-jamming performances are also improved. The image acquisition card has been designed and fabricated as the image acquisition module in this system. What's more, the photoelectric image can be processed with the related processing algorithm. This design puts the image acquisition card based on Camera Link into use in Optical Microscope Pattern Measuring System, which has not been reported in China as far as we know.Firstly, the whole project of the image acquisition system has been introduced, then the principle of system and the characteristics of the chips have been analysed. Three modules including the data collecting module based on Camera Link, the data storing module based on DDR SDRAM and the data transferring module based on PCI interface have been designed, then the function and realization have been discussed in detail. Taking into account the performance of antijam and the global distribution of lines, the printed circuit has been designed. Finally, the internal logic of FPGA has been designed using Verilog HDL, and the control of each module has been realized.