Touch screen and contact positioning method thereof

Abstract

The invention provides a touch screen which comprises a touch screen body and a control circuit. The touch screen body comprises a working layer, a detection layer, an insulating layer, a base layer and a touch layer; the control circuit comprises a power supply, an analog-to-digital converter and a main control chip; the detection layer is a transparent conductive film on which a detection electrode is arranged; the working layer is provided with a resistance strip line; the two ends of the strip line are arranged on the edge of the working layer; the strip line occupies the whole working layer in a certain shape; the power supply is selectively conducted with the two ends of the strip line under the control of the main control chip and forms a loop through the detection electrode when the touch screen body is touched; and the main control chip obtains a resistance value of the touch screen body through the analog-to-digital converter and determines a contact position according to the resistance value.

Description

technical field [0001] The invention relates to a touch screen, in particular to a resistive touch screen capable of supporting single-point or two-point input and a contact point positioning method thereof. Background technique [0002] Existing touch screens can generally be classified into several types according to their working principles: resistive, capacitive, infrared, surface acoustic wave, electromagnetic, and pressure sensing. In surface acoustic wave technology, ultrasonic waves are sent horizontally and vertically on the surface of the touch screen through a transducer. When the panel is touched, the acoustic wave energy at the contact point is absorbed, and the sensor detects the change of the acoustic wave to locate the contact point. In infrared technology, light beams are sent horizontally and vertically on the surface of the touch screen through light-emitting diodes. When the panel is touched, the light beams at the touch points are blocked, and the photod...

AI Technical Summary

Problems solved by technology

In this scheme, the two layers of conductive film are divided into several rectangular conductive strips, and the conductive strips on each layer of conductive film are parallel to each other and insulated, and multiple rows and columns are arranged in a matrix to form conductive areas at the intersections to correspond to Multiple touchable positions, but this solution has the following defects: 1. Only one point can be identified in each conductive area, and only one point can be identified when multiple contacts fall in the same conductive area; 2. Each rectangular conductive area Both ends of the strip need to be provided with electrodes, which are connected to the control circuit through leads. An increase in the number of conductive strips will increase the number of control circuit components, resulting in increased volume and increased manufacturing costs. Too few conductive strips will affect the resolution of the touch screen.

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