How to Detect Capacitive Multi-touch Screen?

Views : 316
Author : Capacitive Touchscreen supplier
Update time : 2021-07-06 15:09:39
In order to achieve multi-touch, the capacitive screen depends on increasing the electrode of mutual capacitance. To put it simply, it divides the screen into blocks, and a set of mutual capacitive modules in each area works independently, so the capacitive screen can independently detect the touch of each area, and after processing, it can simply achieve multi-touch.

CTP (Capacity Touch Panel) uses the current induction of the human body to work. The capacitive screen is a four-layer composite glass screen, the inner surface and interlayer of the glass screen are coated with a layer of ITO (nanometer indium tin metal oxide), the outermost layer is only 0.0015mm thick silica glass protective layer, the sandwich ITO coating is used as the working face, four electrodes are drawn out from the four corners, and the inner layer ITO is the screen layer to ensure the working environment.

When the user touches the capacitive screen, due to the human electric field, the user's finger and the working face form a coupling capacitance, because there is a high-frequency signal connected to the working face, so the finger absorbs a very small current. This current flows out from the electrodes on the four corners of the screen, and in theory, the current flowing through the four electrodes is proportional to the distance from the fingers to the four corners. The controller obtains the position through the precise calculation of the four current ratios. It can achieve 99% accuracy and has a response speed less than 3ms.
Related News
Market Prospect of Outdoor LCD Advertising Machine Market Prospect of Outdoor LCD Advertising Machine
May .25.2022
The outdoor LCD advertising machine uses LCD monitors to play video advertisements, which is especially suitable for the comprehensive multimedia technology of high-end brands to deliver a full range of product information and promotional information to consumers. Different from newspapers, magazines, radio, television and other media, LCD advertising machine has a wide range of applications and remarkable effects.
Comparison of 3 Different Models of BOE 18.5-inch LCD Screen Comparison of 3 Different Models of BOE 18.5-inch LCD Screen
Apr .21.2022
There are 3 outstanding models of BOE's popular 18.5 inch LCD screen, namely the DV185WHM-NM1, QV185FHB-N81 and MV185WHB-N20, of which the MV185WHB-N20 is available in both normal and high brightness versions. So what's the difference among them?
3 Common Problems of Using Capacitive Touchscreen 3 Common Problems of Using Capacitive Touchscreen
Feb .24.2022
Users may encounter some problems when using capacitive touch screens. When using it for the first time, the user first correctly installs the driver needed for the capacitive touch screen according to the requirements of the relevant instructions, and then runs the screen calibration program to calibrate the screen. In fact, the touch screen will be calibrated before it leaves the factory, so end users don't have to worry. In addition, users may encounter the following three situations when using a capacitive touch screen.
3 Differences Between Assembly LCD Module and Original LCD Screen 3 Differences Between Assembly LCD Module and Original LCD Screen
Feb .17.2022
In the LCD display screen industry, LCD has been called two ways, one is the assembly LCD module, the other is the original LCD screen. Do you know the difference between them? To sum up, there are three main obvious differences.
Know more about LCD technology?