Touchscreen

Hear Music touchscreen

Ecobee4 on the wall from an angle showing home screen

CERN-Stumpe Capacitance Touchscreen

Keypad-Touchscreen

Comdex 1986

Comdex 1986

Touchscreen technology is a method of input on a display that allows users to operate a device by touching its screen. The technology has become ubiquitous in the modern world, found in a wide range of devices from smartphones and tablet computers to information kiosks, ATMs, and point of sale systems.

History

The development of touchscreen technology began in the 1960s, with the first touchscreen invented by E.A. Johnson at the Royal Radar Establishment, Malvern, UK. The early touchscreen could only read one point of contact at a time, and it was used in air traffic control. The technology evolved over the decades, with significant advancements such as the invention of the capacitive touchscreen in the 1980s, which could process multiple points of touch simultaneously.

Types of Touchscreens

There are several types of touchscreens, each using different methods to detect touch.

Resistive Touchscreens

Resistive Touchscreens work by pressing two conductive layers together, typically a flexible top layer and a rigid bottom layer. When a user touches the screen, the two layers make contact at that point, and the change in electrical current is used to determine the touch location.

Capacitive Touchscreens

Capacitive Touchscreens operate by sensing the electrical properties of the human body. These screens are coated with a material that can store electrical charges; when the screen is touched, a small amount of charge is drawn to the point of contact, altering the electrostatic field, which is measured to determine touch location.

Infrared Touchscreens

Infrared Touchscreens use an array of X-Y infrared LED and photodetector pairs around the edges of the screen to detect a touch point. When an object interrupts the infrared light, the sensors can determine the touch location.

Surface Acoustic Wave (SAW) Touchscreens

Surface Acoustic Wave (SAW) Touchscreens utilize ultrasonic waves that pass over the touchscreen panel. When the panel is touched, a portion of the wave is absorbed, and the change in the waves is used to determine the touch location.

Applications

Touchscreen technology has a wide range of applications. In consumer electronics, touchscreens are used in devices such as smartphones, tablet computers, and laptops. In retail, they are found in point of sale systems and self-service kiosks. In the automotive industry, touchscreens are used in car infotainment systems. They are also used in industrial settings for control panels and in healthcare for patient monitoring systems.

Advantages and Disadvantages

Touchscreens offer several advantages, including ease of use, accessibility, and the ability to interact directly with what is displayed, eliminating the need for a separate input device like a mouse or keyboard. However, they also have disadvantages, such as susceptibility to physical damage, fingerprints, and in some cases, less accuracy than traditional input methods.

Future of Touchscreen Technology

The future of touchscreen technology is likely to see further innovations, including more advanced multi-touch capabilities, improved durability, and the integration of tactile feedback to simulate the feel of physical buttons. Developments in materials science, such as the creation of flexible and stretchable touchscreens, could lead to new device form factors and applications.