What is capacitive touch screen?
A capacitive touch screen is a device screen that works to interact with the touch of a finger. Capacitive touchscreen devices are typically handheld devices and can be connected to networks or computers through an architecture that supports various components, including satellite navigation devices, personal digital assistants, and cell phones.
A capacitive touch screen is activated by human touch, which acts as an electrical conductor used to stimulate the electrostatic field of the touch screen. However, special gloves that generate static electricity or special stylus pens can be used.
Capacitive touchscreens are built into input devices, including all-in-one computers, smartphones, and tablets.
The capacitive touchscreen consists of an insulator-like glass coating that is covered with a transparent conductor such as indium tin oxide (ITO). The ITO is attached to glass plates that compress the liquid crystals in the touchscreen. Activation of the user screen creates an electronic charge that causes the liquid crystal to rotate.
Capacitive touch screen types are as follows:
Surface capacitance: Coated on one side with a small voltage conductive layer. It has limited resolution and is often used in kiosks.
Projected Capacitive Touch (PCT): Uses etched conductive layers with electrode grid patterns. It has a robust architecture and is widely used in point of sale transactions.
PCT Mutual Capacitance: A capacitor is located at each grid intersection over the applied voltage. It makes multitouch easier.
PCT self-capacitance: Columns and rows work individually using current counters. It has a stronger signal than PCT mutual capacitance and works optimally with one finger.
Other touch screen technologies include resistive, surface acoustic waves (SAW), and infrared (IR).