Based On Usb2.0 High-resolution Linear Ccd Image Acquisition System

Machine vision technology is a combination of optical, mechanical, electronic, hardware and software. It involves a computer, image processing, pattern recognition, artificial intelligence, signal processing, optical electromechanical integration, and other fields. Since the start of development, it has been more than 20 years of history, the automatically detects in the industrial production line of products is one of most representative application, such as grain appearance quality inspection, plate fracture detection, thin-film transistor liquid crystal display (TFT-LCD) mura detection etc.But the corresponding report about machine vision system applied to organic light-emitting display (OLED) defect inspection is not many. As we all know, OLED because of its light weight, thin thickness in response to higher speed and excellent contrast characteristics, it occupies an important position in the flat panel display industry. So the development of the corresponding defect detection systems are another application of machine vision research.Completed the design of a complete set of OLED defect inspection machine vision system hardware circuit and the corresponding driver.Firstly, the work principle and main features of CCD are presented briefly. Then the work principle of main chip and function circuit design are analyzed detailedly, implementation of various functional modules with Verilog HDL and the underlying drivers. The main chips used in this system include linear CCD sensor TCD1500C, special purpose image processing chip AD9822, complex programmable logic devices EPM7128S, and USB2.0 interface chip CY7C68013A. During the design process and give full play to each chip's outstanding performance, with EPM7128S completed TCD1500C driving pulse, the circuit implementation simple and flexible and can work with different CCD. In image acquisition, AD9822 is a dedicated CCD image processing chip, in the CCD signal to do high-precision A / D conversion before the first signal optimization and pre-processing, improve the image acquisition of the reliability and stability. Interface uses USB2.0, give full play to the Universal Serial Bus has a plug-and-play, easy to expand and so on.Firstly, paper introduces the frame the whole system design and implementation of programs; in the follow-up, the two sections of the system hardware circuit design and system software design for an in-depth research; the last to come out sampling OLED picture, a detailed analysis of the system encountered in debugging some typical problems and solutions, and noted that the system problems, improve the methods are given.