Rain and other fluids have the potential to wreak havoc on touch screen performance, but for most non-consumer designs – think medical, laboratory, industrial, and a whole host of outdoor information and kiosk applications – operating only on clear, sunny days is not really an option!
While resistive touchscreens can operate with water or other fluids on the screen, the durability of resistive membrane may mean that they are not suited for operation in environments where dust, dirt and abrasive materials could damage them. Surface and projected capacitive touchscreens are more durable, but rain and other, nastier fluids containing dissolved solids and gases that can make them conductive can degrade performance. And optical systems may be prone to detecting droplets on the screen as a touch, leading to erroneous performance.
At andersDX we develop and offer a wide range of solutions to protect touch screens from these problems, which is why we are so taken with Baanto’s patented optical position sensing technology, ShadowSense™.
As the company’s white paper ‘Rain and Fluid Detection for Touch Screens’ explains, ShadowSense touch screens report not just the position of a touch object but also the size and opacity of that object, which is known as the shadow density. This information, coupled with a dashboard application that enables the designer to define the size limits of a touch point, the opacity and separation distance between adjacent touch points, helps to reduce or even eliminate false touch reporting due to fluids on the touch screen.