Capacitive Touch Screen

Definition - What does Capacitive Touch Screen mean?

A capacitive touch screen is a device display screen that relies on finger pressure for interaction. Capacitive touch screen devices are typically handheld, and connect to networks or computers via an architecture that supports various components, including satellite navigation devices, personal digital assistants and mobile phones.

A capacitive touch screen is activated by human touch, which serves as an electrical conductor used to stimulate the electrostatic field of the touch screen. However, special gloves that produce static electricity or specialized stylus pens may be used.

Capacitive touch screens are built into input devices, including all-in-one computers, smartphones and tablet PCs.

Techopedia explains Capacitive Touch Screen

The capacitive touch screen is built with an insulator-like glass coating, which is covered with a see-through conductor, such as indium tin oxide (ITO). The ITO is attached to glass plates that compress liquid crystals in the touch screen. User screen activation generates an electronic charge, which triggers liquid crystal rotation.

Capacitive touch screen types are as follows:

Surface Capacitance: Coated on one side with small voltage conductive layers. It has limited resolution and is often used in kiosks.
Projected Capacitive Touch (PCT): Uses etched conductive layers with electrode grid patterns. It has robust architecture and is commonly used in point-of-sale transactions.
PCT Mutual Capacitance: A capacitor is at each grid intersection via applied voltage. It facilitates multitouch.
PCT Self Capacitance: Columns and rows operate individually via current meters. It has stronger signal than PCT mutual capacitance and functions optimally with one finger.

Other touch screen technologies include resistive, surface acoustic wave (SAW) and infrared (IR).