Working of Touchscreens

• 23 Dec 2023

A touchscreen is a surface that combines two functions: to receive inputs for a computer (say, tapping on an app) and to display the output (launching the app).

• There are two most common types of touchscreens: capacitive and resistive.
  • Capacitive touchscreens are used in most smartphones and tablets.They work by sensing the electrical properties of the human body when a finger touches the screen.
    • Such a touchscreen consists of a surface with a grid of capacitors. Capacitor stores electric charges and when a finger touches the screen, sensors detect the distortion and relay the information to determine the touch location.
  • Resistive touchscreens are pressure-sensitive and work by sensing the pressure applied to the screen.
    • Resistive touchscreens are cheaper to make and require less power to operate.
    • A resistive touchscreen uses resistance. That is, there are two sheets, both conductors, separated by a small gap. When a finger touches one sheet, it moves it at that point to touch the underlying sheet, allowing a current to pass there.