Identification method of multi-touch of infrared touch screen

Abstract

The invention relates to an identification method of multi-touch of an infrared touch screen, which comprises the following steps: determining blocking coordinate points of two adjacent edges thereof at X-edge or Y-edge of the touch screen through scanning by a vertical echelette and determining infrared transmitting tubes of the two coordinate points; respectively moving inwards the infrared transmitting tube with one bit from the infrared transmitting tubes to blocking point width and positioning the two infrared transmitting tubes to give out light; according to that the transmitting tubesgive out light, determining two new coordinate points at X-edge or Y-edge of the touch screen again; calculating the distance between the two coordinate points at two adjacent edges and the two new coordinate points at two adjacent edges after moving and giving out light; and judging the blocking point with large distance to certainly be below the blocking point with small distance. The contribution of the invention to the prior art lies in that a relative position of the multi-point combination can be rapidly and exactly positioned, thereby increasing speed by more than 50% compared with theprior art; and the invention has simple steps, saves software resources and reduces cost.

Description

technical field [0001] The present invention relates to an electronic touch screen, in particular to a multi-touch recognition method of an infrared touch screen. The method provides an effective judgment method by changing the scanning mode without changing the existing screen structure, and solves the problem of multi-touch X , the accurate positioning of the relative position of the Y coordinate point. Background technique [0002] With the rapid development of electronic technology, the electronic touch screen has developed from the previous single point to the current multi-point, such as the current popular electronic products such as Apple tablet computers. These multi-point touch screens use capacitive multi-point touch screens, and Capacitive multi-touch screens are basically applied to electronic touch screens below 5 inches, and to apply multi-point electronic touch screens to screens above 5 inches, you need to use infrared electronic touch screens. Infrared touc...

AI Technical Summary

Problems solved by technology

[0004] Second, quickly scan to distinguish the coordinates generated at different times (assuming that two points cannot be clicked at the same time), in this way, relying on the rapid scanning of the infrared screen, it is possible to distinguish the small time difference between the two scanned objects, and judge according to the sequence of clicks In this case, it relies on fast scanning to distinguish the sequence of touches. The faster the scanning speed, the more accurate it is. However, this method may produce wrong judgments when encountering simultaneous clicks. At the same time It needs to be combined with other methods to judge the continuous touch point

Pre-judge the position of the next click through the fitting algorithm, and then combine the scanning results to determine the correct coordinates. This method predicts the position of the next touch point based on the previous movement trend, and selects the closest point based on the scanning results. As the current touch position, in this method, when two touch positions cross and turn, it is easy to make a judgment error

[0006] The above-mentioned several or several software identification methods can eliminate certain ghost points, but because these methods are realized through certain assumptions, the problem of ghost points cannot be completely eliminated in practical applications, resulting in frequent occurrence of touch points in actual use. Large jitter of points, wrong judgments, etc.; making the existing multi-point infrared touch screen unable to achieve smooth and accurate touch effects when performing multi-touch, it can only be used in simple applications such as display

[0007] In addition, the above judgment method will use a large amount of software resources and take a long time. In actual applications, there will be a phenomenon of delayed response, which cannot meet the requirements for applications such as two-point writing and multi-touch games.

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