A method for realizing multi-touch on a surface acoustic wave touch screen

Abstract

The invention discloses a method for realizing multi-touch of a surface acoustic wave touch screen. The method comprises the following steps of step a: controlling a transmitting transducer to transmit acoustic signals to an X axis and a Y axis respectively, wherein when the acoustic signals transmitted to the X axis pass through a reflecting unit in one of the reflection stripe arrays on the X axis, each reflecting unit reflects the acoustic signals into a plurality of acoustic signals in different directions; when the acoustic signals transmitted to the Y axis pass through a reflecting unit in one of the reflection stripe arrays on the Y axis, each reflecting unit reflects the acoustic signals into a plurality of acoustic signals in different directions; step b: when N touch points are touched synchronously, N*N two-dimensional coordinates can be obtained, and orderly judging the N*N two-dimensional coordinates, when the acoustic signals passing through any one two-dimensional coordinate are blocked, then judging the coordinate to be a true touch point. The method for realizing multi-touch of the surface acoustic wave touch screen provided by the invention can support multiple touch points to be touched synchronously and can quickly determine the true touch point.

Description

technical field [0001] The invention relates to a surface acoustic wave touch screen, in particular to a method for realizing multi-point touch on a surface acoustic wave touch screen. Background technique [0002] The current touch screens mainly include surface acoustic wave, infrared, and capacitive types. Among them, the surface acoustic wave touch screen has become the most popular among several mainstream touch screens due to its advantages such as high resolution, short response time, strong environmental adaptability, good stability, and good light transmission. A touch screen with promotional value. [0003] The existing ordinary surface acoustic wave touch screen only has two physical positioning axes perpendicular to each other, the X axis and the Y axis. Based on the principle of axis intersection, a touch point can be accurately identified and a unique set of position coordinate data can be obtained. However, for two or more When the touch points are operated a...

AI Technical Summary

Problems solved by technology

[0010] The patent adds a Z-axis that can assist in screening ghost points. After adding the Z-axis, a maximum of two physical touch objects can be recognized at the same time, and a set of U-axis perpendicular to the Z-axis can be added, and a maximum of three physical touch objects can be recognized at the same time. , so theoretically there are N groups of coordinate axes, and N-1 physical touch objects can be identified at the same time, but increasing the number of coordinate axis groups also requires adding corresponding reflection stripe arrays around the touch screen body, and the surface acoustic wave signal passes through multiple groups of reflection stripes A lot of messy signals are generated behind the array, and the transducers are easy to be received, which seriously affects the firmware system’s recognition of coordinate points. At the same time, adding multiple sets of reflective stripe arrays requires a wider touch screen around the body to meet the spatial layout requirements of the reflective stripe array. It runs counter to the current market demand for light weight, narrower, borderless and flat touch screens, and the existing processing technology cannot produce surface acoustic wave touch screens with N sets of coordinate axes

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