What is capacitive and resistive touch screen?
Apr 19, 2024
Capacitive and resistive touchscreens are two common technologies used in touchscreen devices, each with its own principles of operation:
Capacitive Touchscreen:
Capacitive touchscreens work based on the electrical properties of the human body. They are made of layers of glass coated with a conductive material like indium tin oxide (ITO).
When you touch a capacitive touchscreen with your finger (which is conductive), it disrupts the screen's electrostatic field, causing a change in capacitance at the point of contact.
The device detects this change in capacitance and calculates the touch point. This technology allows for multi-touch gestures (e.g., pinch-to-zoom) because it can detect multiple points of contact simultaneously.
Capacitive touchscreens are generally more responsive and durable than resistive touchscreens. They are commonly used in smartphones, tablets, and other modern touchscreen devices.
Resistive Touchscreen:
Resistive touchscreens consist of several layers, typically two flexible sheets separated by a small gap. The inner surface of each layer is coated with a resistive material, and the outer layers are conductive.
When you press on a resistive touchscreen, the two layers come into contact at the point of touch, creating a circuit. This changes the electrical current running through the screen.
The device detects this change in electrical current and calculates the touch point. Resistive touchscreens typically only support single-touch input.
Resistive touchscreens are less expensive to produce compared to capacitive touchscreens, but they are generally less responsive and have poorer visibility because of the additional layers.
They are commonly found in older devices such as some GPS units, industrial control panels, and certain types of kiosks.
In summary, capacitive touchscreens rely on changes in capacitance to detect touch, while resistive touchscreens rely on changes in electrical resistance. Each technology has its own advantages and is suitable for different types of applications.