Touch screen is very common in our day-to-day life including mobile phones, laptops, ATM machines, ticket vending machines etc. We can interact with our device via touch screen and it works both as input and output devices. It has reduced the use of mouse and keyboards with our daily used personal computers.
Types of touch screen
There are several types of touch screen technology we use today. Some of these types of touch screens are given bellow.
- Resistive touch screen
- Surface capacitive touch screen
- Projected capacitive touch screen
- SAW touch screen
- Infrared touch screen
- Optical imaging touch screen
Resistive touch screen
Resistive touch is the most popular and most used touch screen technology. This is also a lowest cost touch screen technology we use today. It needs low power to run.
This touch screen is consisting of a glass panel and a film. These glass panel and film is covered with a thin metallic layer. They are also separated by a narrow gap. If we touch the screen then the two-layer come contact with each other. It makes the flow of electrons. Thus, a resistive touch screen works.
Surface capacitive touch screen
Surface capacitive touch screen has the popularity just after resistive touch screen technology. Here, a transparent electrode layer is placed over a glass which is protected by a cover.
When we touch the screen, it reacts with the static electrons of our body. Then some electrons come to our body from the screen which creates a decrease of electron on that place of the screen. This reduction of electron is detected by a sensor. These types of touch screen give more clear images than resistive touch screen but it requires direct or indirect contact with our body to work.
Projected capacitive touch screen
Projected capacitive touch screen gives very high-quality image clarity. It is similar to surface capacity touch screen. These types of touch screens can be activated by surgical gloves also. It consists of a sheet of glass which embedded transparent electrode films and an IC chip.
SAW touch screen
SAW stands for Surface Acoustic Wave which based upon two transducers and a reflector placed on the glass surface. Transducer receives the bouncing wave and absorbed, for which the touch is detected. SAW give high touch life and better scratch resistance than capacitive one. These types of touch screens have also excellent image clarity.
Infrared touch screen
Infrared touch screen technology does not overlay the display with additional screen rather they use IR emitters and receivers. It has unlimited touch life and highest image clarity and light transmissions.
It gives us the best image quality but it is sensitive to water or other liquids. In infrared touch screen we can set up a grid of infrared beams across the panel.
Optical imaging touch screen
Optical imaging touch screen is designed to detect touch through infrared cameras and disruption of light strips. This is the most versatile options to touch screen technology. They use optical sensors to detect the touch. Here two infrared imaging sensors are positioned at the top.