How does a capacitive touchscreen work?

https://www.irtouch.net/product_p5.html

A capacitive touchscreen works by detecting the electrical properties of the human body. It relies on the fact that the human skin conducts electricity.

 

Here's how it works in simple steps:

 

Layered Structure: The screen is made of several layers, including a protective outer layer of glass or plastic and a conductive layer underneath it.

 

Electrical Field: The conductive layer creates an electrostatic field across the screen by applying a small electrical charge. This layer is usually made of materials like indium tin oxide (ITO).

 

Touch Detection: When your finger touches the screen, it disturbs the electrostatic field at that specific point. Your body, being conductive, pulls some charge away from the screen.

 

Location Tracking: Sensors located at the edges or behind the screen detect the change in the electrical field. The system uses this information to pinpoint the exact location of the touch.

 

Processing Input: The touchscreen controller then processes the coordinates and sends them to the device’s operating system, which interprets your touch as a specific command (tap, swipe, etc.).

 

Capacitive touchscreens are sensitive to light touches and support multi-touch gestures (like pinching to zoom), unlike resistive screens that require pressure.