Research On The Electrical Control System Of PDP Assembly Machine (Ⅱ)

With the advent of digital information age, the use of flat-panel display as a digital information display device has become the trend. Plasma display panel (PDP) is an ideal device to achieve large-screen wall-mounted display. When compared with others, it has many advantages such as thin in thickness, light in weight, large screen, wide viewing angle, quick response and so on. This paper is based on the assembly machine equipment, which is one of equipments in 42" and 50" PDP display production line of Sichuan Changhong Electric Co. Ltd. It achieves the purpose of the automatic alignment of the front and the back PDP display glass substrates. The project got much support from the National Development and Reform Committee and the Industry and Information Technology Ministry.This paper introduces the principle of PDP displays and the production processes of AC-PDP color display at first. Then, it gives the detailed hardware design and software design of the control system in the PDP assembly machine. The hardware design mainly includes a detailed discussion of the electrical system design, the main features and specifications, hardware implementation and the control methods of various implementing agencies. And the software design of the whole control system mainly includes the action processes in auto mode and the control methods in manual mode. Finally, it studies the visual positioning system, which is a key part of the device.This paper studies a scheme which uses the image as a detection signal, to achieve the precise positioning between the front and the back PDP glass substrates. By collecting and amplifying the marks on the front and the back glass substrates through the CCD cameras, the visual positioning system will automatically calculate the displacement difference between the front and the back glass substrates. And then the visual positioning system drives the visual positioning platform to achieve the precision positioning in three degrees of freedom which are X, Y andθ. The positioning accuracy is±5μm . Finally, this paper studies the method of finding the center location of the mark and makes the simulation.