Surface acoustic wave touch panel system

摘要

A system for recognizing and locating a touch induced perturbation of a surface acoustic wave propagating along one of a multiplicity of paths disposed transverse to a predetermined coordinate axis on a surface of a touch panel and for utilizing the magnitude of the perturbation to produce a control effect. The system comprises a substrate having a surface capable of propagating surface acoustic waves and is so characterized that a touch on that surface causes amplitude damping of a surface wave passing through the region of touch which damping is related to touch pressure. A transducer, responsive to touch-perturbated surface waves develops an output signal having a first characteristic indicative of the position of the touch on the substrate surface and having a second characteristic indicative of touch pressure. A control system, which includes a memory and a computer, upon receipt of the output signal, responds to the first characteristic to develop a first control signal reflecting the location of the touch and responds to the second characteristic to develop a second control signal reflecting touch pressure.