A Method for Automatic Elimination of Temperature Difference Drift by Ultrasonic Propagation

Abstract

The invention discloses a method for automatically eliminating temperature difference drift through ultrasonic transmission. First, set the initial velocity of ultrasonic waves as V0, the initial temperature of the ultrasonic pen as T0, the real-time temperature of the ultrasonic pen as T0', the initial temperature of the touch screen body as T1, and the real-time temperature of the touch screen body is T1'; when the temperature difference between the real-time temperature T0' of the ultrasonic pen and the initial temperature T0 of the ultrasonic pen is greater than the set threshold, the initial velocity V0 of the ultrasonic wave is corrected to the real-time propagation speed V1. After correction, the ultrasonic wave enters the touch screen at the real-time propagation speed V1 When the temperature difference between the real-time temperature T1' of the touch screen body and the initial temperature T1 of the touch screen body is greater than the set threshold, the real-time propagation velocity V1 is corrected to the real-time propagation velocity V2, and after correction, the touch coordinates are determined according to the real-time propagation velocity V2. The invention can automatically compensate the transmission speed of the ultrasonic wave according to the change of the external temperature, so as to achieve the purpose of accurate touch.

Description

technical field [0001] The invention relates to the technical field of touch screens, in particular to a method for automatically eliminating temperature difference drift through ultrasonic wave propagation. Background technique [0002] As we all know, the input system of the touch screen is composed of a touch screen body, a touch screen control system, a corresponding control device and a corresponding program. Among them, the touch screen controller detects touch information from the touch point, converts the touch point into touch coordinates, and then sends it to the CPU, and it receives and executes commands from the host CPU at the same time. The basic principle of the touch screen is: when a finger or other object touches the touch screen body at the front of the display, the touched position (in the form of coordinates) is detected by the touch screen controller and sent to the host CPU through the serial port (RS232) or USB, thereby Confirm the input information....

AI Technical Summary

Problems solved by technology

However, in the actual use process, since the electrical parameters of the touch screen body and touch detection electrical equipment will change with the change of temperature, the propagation speed of the ultrasonic wave in the pen core and the touch screen body will also change accordingly, that is, the propagation speed of the ultrasonic wave It is easy to change with the temperature drift of the touch screen body, and the final result is that the touch coordinates are prone to drift and the touch accuracy is poor.

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