A touch screen is a display device that allows the user to interact with a computer by using their finger or stylus. They're a useful alternative to a mouse or keyboard for navigating a GUI (graphical user interface). Touch screens are used on a variety of devices, such as computer and laptop displays, smartphones, tablets, cash registers, and information kiosks. Some touch screens use a grid of infrared beams to sense the presence of a finger instead of utilizing touch-sensitive input.
How is a touch screen different than a mouse?
A computer mouse and touch screen have many similarities. Many of them are mentioned in the how do you use the touch screen section above.
One of the most significant differences between a mouse and a touch screen is the ability to hover. Almost all touch screens can only detect input when your finger is in direct contact with the screen. However, a computer mouse uses a cursor that allows the user to view information by moving the pointer over an object, but not clicking on it. For example, this link to Computer Hope shows the text "Visit the Computer Hope Page" when hovered over using a computer mouse. However, a user with a touch screen cannot see this text because if they place their finger on the link, it opens the link.
Where are touch screens used?
Today, the touch screen is one of the most popular types of input devices. Below are some places and examples of where touch screens may be used.
- All-in-One computer
- Arcade game
- ATM
- Car GPS
- Camera
- Car stereo
- Cash register
- Digital camcorder
- E-book
- Electronic whiteboard
- Factory machine
- Fitness machine
- Gas station
- Grocery self-checkout machine
- Handheld game console
- In-flight entertainment screen
- Kiosk
- Laptop
- Large interactive screen
- Medical equipment
- POS machine
- Sewing machine
- Signature pads
- Smartphone
- Tablet
- Ticket machine
- Touch screen printer
Why are touch screens used?
Below are the reasons a manufacturer may decide to use a touch screen, instead of another input method, such as physical buttons.
- Touch screens are intuitive, especially to younger generations of users.
- Having one touch screen instead of several buttons can make a device smaller.
- Cheaper to design and manufacture a device with one screen instead of on with a screen and buttons.
Touch screen technologies
Not all touch screens are the same. Different technologies can be utilized to allow a user to interact with a screen. Some technologies may work with only your finger, and other technologies may allow other tools, like a stylus. Below is a brief description of each of these technologies.
Capacitive
A capacitive touch screen is coated with a special material that stores an electrical charge that is monitored by circuits at each corner of the screen. When you touch a capacitive touch screen, a small amount of the electrical charge is drawn from the point of contact to indicate where you touched the screen.
To use a capacitive screen, you must use your bare finger or a specially designed capacitive stylus. Most users experience this type of screen technology when attempting to use a smartphone touch screen while wearing gloves and being unable to do anything.
There are specially designed gloves that allow one or more fingers to interact with a capacitive screen.
Resistive
A resistive touch screen is coated with a metallic electrically conductive and resistive layer that detects the pressure of your finger or another object. This technology is often a more affordable solution compared to capacitive, but can be damaged by sharp objects touching the screen.
Surface acoustic wave
A SAW (surface acoustic wave) or surface wave touch screen sends ultrasonic waves and detects when the screen is touched by registering changes in the waves. This technology is more advanced than the other two, but does not work with hard materials, and can be affected by outside elements.
Infrared
Infrared touch screens utilize a matrix of infrared beams that are transmitted by LEDs with a phototransistor receiving end. When a finger or other object is near the display, the infrared beam is blocked. That interruption gives the device input to where your finger or another object is positioned.