The Basics of Waterproofing Capacitive Touchscreens | Cypress Semiconductor
The Basics of Waterproofing Capacitive Touchscreens
Author: Erik Anderson
Touchscreens get wet from time to time. It is frustrating to a user if the touchscreen controller cannot handle water appropriately. It’s important to understand what waterproofing really means for capacitive touchscreens, how the physics of capacitive sensing is affected by water, and why your choice of touchscreen controller makes a difference.
What Does Waterproof Mean, Exactly?
There are international standards that cover waterproofing in detail. The International Electrotechnical Commission (IEC) standard IEC-60529, for example, contains definitions for Ingress Protection (IP) ratings. One of the highest ratings a product can have is IP-67, meaning it can handle a significant amount of dust (dust rating of 6) and can be immersed in water up to 1m (water rating of 7) without damage. Few mobile devices can meet this requirement, however, and the IP rating is not widely used for capacitive touchscreen product requirements. Waterproof requirements for touchscreens usually revolve around the user experience and how the product behaves in the presence of water, rather than by using destructive tests. Although not formally standardized, two subset definitions of waterproofing are becoming widely used in the industry: Water Rejection and Wet Finger Tracking.
To read more, visit www.eetimes.com.