The proliferation of touch screens, a technology that has been around for many years, can be seen in common consumer electronic devices. The growth of the touch screen market is being driven primarily by demand in the mobile phone and consumer electronics industries - especially personal digital assistants, portable game consoles, and portable navigation devices.
An increasing number of vendors are developing new technologies to improve the performance characteristics of touch screens. At present, touch screens use resistive- and capacitive-based technologies that have a few drawbacks. Some of these cons are that they perform poorly in outdoor conditions, they suffer battery drain and that they require slightly high pressure for touch sensation.
Frost & Sullivan has however taken note that RPO Technologies, based in Australia, has introduced its novel digital waveguide touch (DWT) products, developed using its polymer optical waveguide technology. The optical waveguides are made using RPO's proprietary 'inorganic polymer glass', which allows RPO to manufacture flexible substrate-based waveguides of large sizes and at very low costs.
DWT does not use touch panel overlays; rather, it relies on invisible light rays immediately above the display surface. The advantage of using these light rays is the lack of impact on screen clarity and reflectivity. The origin of the light beams is a low power semiconductor light source, while the distribution is performed through light channels.
The channelled light passes through the polymer optical waveguide into the bezel of the flat panel display where it is projected through the free space above the display surface. Each of the channels is contained in discrete digital beams and is fed to a pixel on a semiconductor light sensor camera. When one or more light beams are blocked, no light is detected by the camera and it indicates the position of a touch.
According to RPO sources, the resolution of the touch technology can be changed to suit different applications by varying the number of lights beams, resulting in very good accuracy and positioning.
Unlike most touch screens in the market, DWT can detect multiple touches. This allows for multiple simultaneous touch points through various spontaneous gestures, which provide a richer experience through direct mapping compared to single point detection through a finger or a stylus.
As resistive touch screen technologies are by far the most widely used and manufactured, competition among vendors is bringing prices down.
Keeping this in mind, RPO is developing the technology on its own, while working with component suppliers and electronic assembly groups, to help ensure a good cost to performance ratio for the consumer market.
Source: Frost & Sullivan Technical Insights