Research of parallel data processing, anti-light interference infrared touch technology

摘要

Large-size infrared touch screen has long response time and external light interference problems. To solve these problems, this paper proposes a method that divides whole infrared touch screen into several separate scanning units and a master module. Each scanning unit completes touch scanning and touch information processing within its own range. Scanning units are parallel working. Master module gets touch information from each scanning unit through UART bus, processes touch information to get final touch coordinates of the whole screen and reports them to host computer. Through parallel working among scanning-units rather than sequential scanning on full-screen, this method improves the response speed. Through using photodiode and crystal resonator to constitute received signal processing circuit, this method achieves anti-light interference. After response time tested and anti-light interference tested, it has proved that this method achieves a fast response and anti-light interference infrared touch screen system.