Industrial LCD touch screen is divided into non-touch, resistive touch and capacitive touch and other touch methods, and capacitive touch is the more common touch, when the industrial capacitive screen failure how to solve? What are the principles to follow?
Capacitive screen so-called "drift", mainly refers to the following situations.
1. The touch operation to make the wrong action, that is, touch the A point, but the B point to make a touch response
2. No touch but make a wrong action, that is, the body or conductive objects such as close to the screen, has not touched, made a touch response
3. No action on the touch operation, that is, the finger has touched the touch screen, but the screen did not make a touch response
In the introduction of the causes of "drift" before, it is necessary to introduce - the working principle of the capacitive screen.
Capacitive screen is the use of the body's current induction work. Capacitive touch screen is a four-layer composite glass screen, the inner surface of the glass screen and the interlayer is coated with a layer of ITO (transparent conductive film), the outermost layer is a thin layer of silica glass protection layer, the interlayer ITO coating as a working surface, four corners lead to four electrodes, the inner layer of ITO shielding layer to ensure a good working environment.
When the finger touch on the metal layer, due to the human body electric field, the user and the touch screen surface to form a coupling capacitance, for high-frequency current, capacitance is a direct conductor, so the finger from the contact point to suck away a small current. This current is divided from the four corners of the touch screen electrodes, and the current flowing through the four electrodes is proportional to the distance from the finger to the four corners, the controller through the precise calculation of the proportion of the four currents, the location of the touch point.
It is because of this working principle of the capacitive screen, which led to the existence of the phenomenon of screen jumping. After clarifying the working principle of the capacitive screen, it is easy to know the cause of the capacitive screen "drift".
About the capacitive screen "drift" phenomenon is probably the reason, regardless of what equipment, the first thing to find out the cause of the failure before the right remedy.
