1. The virtual touch screen keyboard executes commands through resistors.
2. The capacitive touch screen executes commands through temperature sensing.
3. Capacitive touch screens are more sensitive Nowadays, most smart devices use capacitive touch screens.
Borrowing: A resistive touch screen is a sensor that converts the physical position of the touch point (X, Y) in a rectangular area into voltages representing X and Y coordinates. Many LCD modules use resistive touch screens. This screen can use four, five, seven or eight wires to generate screen bias voltage and read back the voltage at the touch point.
The capacitive touch screen technology uses the current induction of the human body to work. The capacitive touch screen is a four-layer composite glass screen. The inner surface and the interlayer of the glass screen are each coated with a layer of ITO. The outermost layer is a thin layer of silica glass protective layer. The interlayer ITO coating is used as the working surface, and the four corners are led out Four electrodes, the inner layer of ITO is a shielding layer to ensure a good working environment. When a finger touches the metal layer, due to the electric field of the human body, a coupling capacitor is formed between the user and the surface of the touch screen. For high-frequency current, the capacitor is a direct conductor, so the finger draws a small current from the contact point. This current flows from the electrodes on the four corners of the touch screen, and the current flowing through these four electrodes is proportional to the distance from the finger to the four corners. The controller calculates the position of the touch point by accurately calculating the ratio of these four currents. .
