Multi-point touch identification method for infrared touch screen

Abstract

The invention discloses a multi-point touch identification method for an infrared touch screen, which comprises the steps of determining a rectangular plane coordinate system by taking one corner of the touch screen as the origin of coordinates; scanning the infrared germinate transistors on the screen in the X axis and Y axis directions of the rectangular coordinate system, forming orthogonal light paths according to the shield signals of touch points, and primarily determining the touch point by the crossing point of the orthogonal light paths; performing oblique axis light path scanning in the X or Y axis, and calculating the linear distance between the lowering points, wherein crossing lines are formed by the oblique axis light path at the crossing point of the orthogonal light paths in the X or Y axis and the lowering points are formed by the crossing lines at an infrared receiving tube; and determining the position of the real touch point according to the crossing point of the orthogonal light paths and the linear distance between the lowering points. The multi-point touch identification method for the infrared touch screen has the advantages of accurately determining the real touch point by scanning the primarily determined point by an oblique axis light path scanning mode, and being fast in computing speed without causing errors due to the abnormity of a certain LED (light emitting diode) on the touch screen.

Description

technical field [0001] The invention relates to the technical field of touch screen identification, in particular to an infrared touch screen multi-touch identification method. Background technique [0002] The infrared touch screen uses a pair of infrared emitting tubes and infrared receiving tubes to detect whether there is an obstruction between the two tubes to identify the touch point. Currently, infrared touch screens get more logical touch points than actual touch points when performing multi-touch. A large part of these logical touch points are "false points", that is, the position is not actually touched, so these "false points" need to be removed to confirm the position of the real touch point. [0003] Generally, the existing multi-touch recognition method is: adopt infrared scanning to scan vertically and obliquely one by one. When scanning, one infrared emitting tube corresponds to one infrared receiving tube, and the corresponding infrared emitting tube and in...

AI Technical Summary

Problems solved by technology

Generally speaking, this method can accurately determine the position of the real touch point, but because the number of LED lights on the X-axis and Y-axis is very different, if there is an error of an LED light on the X-axis or Y-axis, after this calculation, we get The coordinates of the touch point will vary by thousands of miles, resulting in the inability to accurately identify the position of the touch point. This shortcoming is particularly serious on small-sized touch screens.

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