Projected capacitive touch screens
Published: 4 January 2016 - Lisa Peake
EDT’s projected capacitive touch panels, available from Manhattan Skyline, provide exceptional interaction capabilities through the most durable materials. Projected capacitive touch panels sense input through a protective layer in front of a display, making them durable and nearly vandal-proof. EDT’s projected capacitive touch panels feature a technology that allows them to be 'tuned' to operate through glass or polycarbonate facings of a variety of thicknesses.
In addition to their exceptional durability, EDT's projected capacitive touch panels support Windows 7 native gesturing and are highly accurate. They are available in various sizes from 3.5 inch to 15.4 inch..
The basic capacitive touch panel structure is made of two parts: touch sensor and cover lens. There are two types of touch sensors. First we have the glass sensor which has advantages in optical performance, durability, and narrow border, then the film sensor which has advantages in thinness, lightness and facilitates (or eases) production.
There are two type of cover lens: glass and plastic.
Typical cover lens thickness varies from 0.55, 0.75, or 1.1 mm for mobile devices, up to 3 mm or even thicker for industrial applications.
The dielectric constant of the cover lens and its thickness have a direct impact on the sensitivity of the capacitive touch panels – a thinner cover lens and/or a higher dielectric constant results in better performance. Plastic (PMMA) has a lower dielectric constant and must behalf the thickness of glass to achieve the same performance.
EDT has developed various types of sensor and cover lens combinations for the capacitive touch panels: Glass to Glass, Glass to film and One Glass only.