What Cables Are Needed with a Touch-Screen?
By Peter Hall
Touch-screens are everywhere these days, from your cellular phone, to the ATM machine, to casinos all over the country. With the explosion of touch-based computing, many people are considering adding a touch-screen monitor to their home computers. Because a touch-screen monitor is an input as well as an output device, connecting one to your computer is more complex than connecting a normal display.
Mostly the same
The display portion of a touchscreen monitor connects to a computer like any standard monitor, with either a VGA or a DVI cable. The monitor also needs power, so it plugs into a standard wall outlet. Some touchscreen monitors have built-in speakers, they will use a 3.5-millimeter headphone jack to plug into any computer audio card.
Because a touch-screen needs to be able to communicate your touches back to the computer, there must be a data connection from the display to the host computer. Some older models of touch-screen use a serial cable, while most newer models use a standard USB cable.
Depending on the how a touch-screen monitor is going to be used, there are four major different technologies that allow the screen to record touches. The Apple iPhone uses a capacitive technology, which monitors changes in the electrical field caused by the human body. This is very accurate, but does not record touches if you are wearing gloves. There are acoustic technologies, which recognize touch by sound, by calculating the difference in time that each of four acoustic transducers "hear" the touch. Resistive touch-screens have been on the market the longest. They work by placing a flexible touch screen panel in front of the screen. The downside is that this panel can distort images or colors on the display. There are also infrared screens that place infrared emitters on the bottom and side of the display and receivers on the top and other side. When your finger breaks the beams, the display records the position. These displays can only record one touch at a time, and the touch points have to be fairly large; however, there is no layer that obscures the image.
More options to consider
Touch-screens tend to have a lot more case options because of where they are installed. Touch screens installed in a casino-style game machine don't need he plastic bezel that a desktop monitor does, so they have mounting brackets to mount the monitor inside an enclosure. Some touch-screen monitors are used as public kiosks; they have security mounting bases to lock them to the counter on which they are installed.
Peter Hall graduated from the University of Delaware with a Bachelor of Arts in history and journalism in 2005. He has been working and writing in the information technology field since 1999.