We’ve been subjected to a deluge of touch screen phones ever since the release of the iPhone, and whilst some provide a smooth and slick experience, others don’t always feel quite up to snuff.
That is because in reality, there are two different types of touchscreen technology that these phones take advantage of – resistive and capacitive.
Whilst capacitive touch screens offer a faster and more responsive experience, resistive touch screens tend to be cheaper to manufacture and have a greater degree of accuracy.
Also, resistive touch screens can also be used with a stylus, which is important for handwriting recognition and writing Asian characters, and arguably a major contributing factor to why capacitive touch phones like the iPhone haven’t gotten such a warm response in the East.
Windows phones have resistive touchscreens as standard, whilst high end devices from companies like LG and Samsung tend to be capacitive. The Windows Mobile operating system is currently unable to support the capacitive touch screen, but all that is set to change with Windows 7 on phones, and steps are being made toward this even on the forthcoming ’6.5′ update.
Resistive touchscreens are composed of several layers of plastic, and input is registered when two of these layers become joined by the external pressure of a finger or stylus, creating an electrical connection.
Capacitive touchscreens are traditionally a glass panel coated with a transparent conductive material. As the human body conducts electricity, any touch on the surface of the screen triggers the electric field and registers the location of the input. Capacitive touchscreens can more readily accept continuous input across the surface, and also track multiple fingers on a single display.
Haptic feedback, the reassuring vibration of menu or item selection, can be done on both resistive and capacitive touchscreens. Resistive touch screen phones include Windows-powered devices like the HTC Touch Diamond 2 and HTC Touch Pro 2.
What does the future of touch phones have in store? Well, the recently released Samsung Jet may have a resistive display, but relies on the internal processor to provide a super-responsive interface rivalling that of capacitive devices. Also, BlackBerry makers RIM have been working hard on a new hybrid interface that is the best of both worlds.
The outer of the two layers has a conductive coating, allowing both types of interaction through a single controller-integrated circuit. According to the company’s application, “the capacitive and resistive functions of the touchscreen do not interfere with each other”.
“Advantageously, a touch of the touchscreen display can be detected prior to contact with the touchscreen display,” the application continues. “Thus, a signal can be sent to the processor for providing a timely response when the touchscreen is touched. For example, a tactile feedback can be provided more quickly, providing a better user feel.”
So, a mobile device marrying the responsiveness of a capacitive interface with the accuracy and stylus support of a resistive touchscreen could well be around the corner…