The Apple Watch display could become safe from screen burn, if a newly revealed patent comes to fruition. The patent, spotted by Apple Insider, shows that Apple has been working on this topic. It was filed in February last year but published by the US Patent & Trademark Office this month
Patent Application 20200218204 refers to electronic devices with display burn-in mitigation and talks about
“An electronic device such as a wristwatch device or other device may have a display. The display may be used to continuously display information such as watch face information. A watch face image on the display may contain watch face elements such as watch face hands, watch face indices, and complications. To reduce burn-in risk for watch face elements, control circuitry in the electronic device may impose burn-in constraints on attributes of the watch face elements such as peak luminance constraints, dwell time constraints, color constraints, constraints on the shape of each element, and constraints on element style. These constraints may help avoid situations in which static elements such as watch face indices create more burn-in than dynamic elements such as watch face hands.
In other words, that lovely Mickey Mouse Watch face has plenty of movement in it, from Mickey’s gyrating hips and tapping toes to his hands pointing at the time. But the clock elements are completely static, so could lead to image burn-in
See, this wasn’t an issue before, because the Apple Watch display automatically dimmed and turned off after just a matter of seconds, so burn-in didn’t happen.
But with Apple Watch Series 5 and its glorious always-on display, everything changed. Although the nature of what’s on screen changes after a short period of inactivity, with elements like digital second counts or second-hands disappearing from view, other parts of the Watch face remained.
While I’m not convinced that the dimmed version would have caused screen burn in less than a very long period of use, it’s obviously something Apple has been taking seriously
Reading patents isn’t easy and I won’t make you look at much more, but essentially, there are plans to ensure things work even better. For instance, “the control circuitry is configured to reduce burn-in risk for the watch face indices by performing a burn-in risk mitigation operation selected from the group consisting of: dynamically shifting a position of the watch face indices on the display and dynamically altering a shape associated with the watch face indices.”
If you ever had a plasma TV, or a cathode ray tube computer, you’ll know that screen burn is a painfully obvious, distracting display artefact you can never get rid of.
Some TVs had screen savers where what was on screen was subtly moved up a pixel, then right, then down, then left so the image was moving frequently but almost imperceptibly. The same principle seems to be one of the prospects here, though my guess is that it will be even subtler, so no movement at all will be apparent
In a series of remarkably casual-looking sketches, the patent lists different mitigation operations to protect the display.
I’ve literally never seen screen burn on any Apple Watch (or iPhone or iPad) I’ve used, but it’s the sort of thing that once seen can never be ignored, so the fact that Apple is aiming to prevent screen burn from taking hold can only be good news.