Apple has just been credited with a new patent. The purpose of this is to facilitate the use of a touch screen when it is wet. This patent covers several types of touch screens, whether resistive or capacitive, as well as those equipped with a pressure sensor, such as the 3D Touch screens of certain iPhones. The system would be able to measure humidity and adapt the operation of the tactile layer.
If you have ever tried to use a capacitive touch screen in a humid environment or with wet hands, you know that its behavior is, in these conditions, very complicated. Either the screen does not capture your finger when you ask for it, or it records phantom interactions, with what this can have as a consequence on the interface (untimely opening and closing, in particular).
Read also – Waterproof smartphones: IP67, IP68 standards, how does it work?
Activate a swimming program on a connected watch? Impossible. Answer a call after cleaning a smartphone? Infeasible. Writing a message in the rain? Very complicated. And yet, these are not delusional uses. These are rather commonplace situations. But the nature of today’s touch screens prevents us from taking advantage of them. Fortunately, Apple might have the solution.
Apple files patent for screen that stays useful when wet
The USPTO, the American agency responsible for intellectual protection, validated on June 28, 2022 a patent that the Cupertino company filed in March 2021. It bears the name “modification of the functioning of an electronic product during exposure to humidity”. In the description, Apple explains how a capacitive or pressure-sensing screen can change its mode of operation when covered in water.
The firm even goes a little further by integrating a humidity sensor which would be able to measure the amount of water on the touch surface. Thanks to this detector, the screen would be able to modify the way it detects an interaction with the user. The document includes the illustration that you can find opposite. The drawing represents an iPhone held by a user who films a scene in the sea. On the screen of the iPhone, you can read ” Wet Mode (Wet mode) on the interface.
It remains to be seen whether this project will really succeed and which electronic devices will benefit from it. The iPhone obviously seems included in the list. But the Apple Watch should be too. Remember that all iPhones have been certified IP67 or more since the iPhone 7 and 7 Plus. Sealing was provided by removing the mechanical Touch ID button on the front, which then became a touch surface with pressure sensor.
Here’s why water drives our touchscreens a little crazy
Why does water drive our touch screens crazy? Because the water is both electrically conductive and resistive (i.e. the inverse of the conductivity). Let’s first recall how a capacitive screen works. You naturally have a slight electric current on the surface of the skin. When you touch a capacitive screen, it will pick up this current and position your finger on its surface. And this system can very precisely locate several fingers at the same time.
Water can conduct electricity. But it does it less well than other elements. We then say that it is conductive, but also resistive. The conductivity of water depends on the elements that make it up: the more minerals there are dissolved in it, the more electricity it lets through. This means that the behavior of a wet screen may also depend on the quality of the water. Which makes it all hard to control.
Source : USPTO