How do Touch Screens Work

Touch screens have become the most popular interface between computers and their users. Owing to the comfort they provide, they are used in a variety of applications like computers, mobile phones, video games. In essence, touch screen is an input device and for it to function effectively, a display is required. Just a touch screen is of no use unless it is installed with the peripherals like PC monitor and the software. The three main parts that constitute these phones are:

• Touch Sensor
• Controller
• Software Driver
• Computer/Laptop/Other Devices

Touch screens are similar to monitors wherein they've a bezel or an overlay on the screen. They in the first step act as a computer monitor. When the screen is touched, the sensitive layers on the screen are designed to convert touch into a signal, as the layers transfer electrical signals between each other. The signal usually is identified by various sensors that are installed in such phones. The touch driver on the screens identify your touch similar to the cursor of a desktop mouse.

Working
In essence, the touch drivers are like the computer mouse. Generally, the left click mouse button functions are performed by touching the screen. The only disadvantage is you can't use the touch screen to right click, as is done by a conventional mouse. If you're playing games or using any software, then it won't identify if your using a mouse or just your fingers!

Resistive Touchscreens
Considered to be the most innovative touch screen technology, resistive technology can be called a transparent keyboard. There are two layers under the touchscreen, the upper layer of polyester and the lower one, made of glass. When you touch the screen, the polyester is touched and it completes the circuit, thereby sending corresponding signals. The integrated chip in such screens helps in figuring out the specific area on the screen or buttons you touch.

Capacitive Technology
These touch screens are made of many layers of glass and it acts like a capacitor, creating electric fields between glass plates and conducting the signal. When the fingers are brought close to the screen, the electric field varies depending on the touching position on the screen.

Ultrasonic Sound Beam
In these type of touch screens, ultrasonic sounds are used instead of light. The ultrasound frequency is generated from the edges of the screen and when we touch the screen, the sound is interrupted and the signal is established.

Near Field Imaging (NFI)
In military and other places were it is difficult to intercept signals, NFI employs the principle of electromagnetic interference. NFI responds to the change in electrical field of glass plates. When we bring the fingers close to the object, the electric field changes and so it registers our touch. For example, electromagnetic waves of a radio are affected when we place our hands or body in front of a radio. Similarly, in this technologies, the closer your hand is, the larger the effect will be.

With innovative technologies making their way into the electronic market, it won't be surprising that in future, the mouse will become non-existent.