Research On Realization Scheme Of Single Layer Multi - Point Projection Capacitive Touch Screen

With the birth of iphone, the transmission of capacitive touch technology gets rapid development and application, especially in the field of mobile phone. Compared with traditional resistive touch screen mobile phone, it has the use of long time and high light transmittance, short response time, etc. Because the capacitance touch screen technology starts relatively late in domestic, some of the core technology and patent protection shielding on the development of domestic technology have formed certain obstacles for its development.In this work, firstly the design of the capacitive screen radiation pattern of ITO thin film is in-depth investigated, because it is the start of the touch screen design, and determine the final performance of the touch screen. This work designs several single-layer self-capacitance and single-layer mutual capacitance patterns, with different characteristics. Corresponding visual optimization design of the line of the screens carried out.Second, the rigid circuit board (PCB) hardware simulation design and soft circuit board (FPC) hardware design are carried out based on the cost considerations for actual touch screen. The design rules and matters needing attention of the whole circuit are illustrated.Third, the corresponding software programming in the multi-touch system is given. The program first collects the data, and processes the data and carries other basic flows, which makes the whole system operates normal. Then, the software design for the filter and power handling are carried out.Final, this work demonstrates the design of the multi-touch system, and the corresponding experimental results are shown.