Research On The Precise Alignment System For The PDP Production

The precise alignment technology is one of the supportive technologies in the production of the Shadow-Mask Plasma-Display Panel (PDP), and makes it possible that the PDP can display good images. The front base board, back base board and the shadow-mask board must match accurately, and then its high-clear display can be realized. This paper presents a scheme that detects the position and alignment of the boards by moirésignal of laser. It analyzes the relationship between the displace error of two gratings and intensity of moirésignal, deduces the equation of double gratings diffraction, builds mathematics model of high precise position detection and simulates it with digital computer. Next this technology is applied to the PDP accuracy alignment system, x-y-θplane precision positioning is realized. Linear position accuracy of±2μm is achieved now and it can fit the request of production of the PDP. In order to improve the dynamic performance and its anti-jamming capability, fuzzy theory and RBF network are applied to the alignment process. In the end, the author brings up the new research way in this task.