The US Patent and Trademark Office on Thursday released Apple's patent application for an OLED display with built-in sensors that will dynamically adjust the brightness of various areas of the screen to compensate for uneven ambient lighting or LED brightness loss due to aging.
Apple does not even use OLED technology in its devices yet, but it is already solving possible problems that are inherent in this type of screens, namely, LED burnout over time. Also, the patent contains a description of the technology for compensating external lighting.
OLED has a number of advantages over LCD screens used in most consumer electronics devices. One of the main ones is that the OLED screen itself emits light, and does not selectively transmit certain colors. Therefore, displays made using OLED technology are thinner and lighter than their LCD counterparts, not inferior to them in color reproduction, brightness and viewing angles. In addition, according to another Apple patent, OLED displays can be placed on both rigid and flexible surfaces.
A significant disadvantage of OLEDs compared to LCDs is that such screens degrade faster - frequently used LEDs “age” faster than others, which leads to non-uniformity of the displayed picture. This effect is called "image stability".
Apple's patent called OLED Photodiode System describes a method for installing light sensors on top, below, or flush with an OLED layer to measure and further compensate for matrix changes. In some versions, photodiodes are located only in certain areas of the screen, while in others they are evenly distributed over the entire area.
Based on the data received from the photodiodes, the controller can determine the difference in picture quality in different parts of the screen. Also, if the ambient light is dim or absent, the controller can adjust the screen brightness accordingly.
But weren't iOS devices able to dynamically adjust screen brightness before? What is the novelty? - Since the sensors are located directly in the screen itself, this improves the detection accuracy and response speed of such a system.
Also, the patent pays attention to the fact that in some cases one light sensor may not be enough, for example, when part of the screen is covered or a shadow falls on it. Using new technology, you can make the darkened part of the screen less bright and extend the battery life.
Also, built-in photodiodes will allow tracking OLED aging and the controller will be able to change the brightness of the “burned out” pixels, which will make the picture on the screen even, regardless of the service life.
Another application of the technology is also possible - during a conversation, the sensors will turn off only those areas of the screen that are directly in contact with the user, leaving visible areas on.
The patent application was filed in 2012 as the inventors are claimed: Stephen Brian Lynch, Paul Stephen Drzaic, Benjamin Mark Rappoport, Fletcher R. Rothkopf, John Patrick Ternus and Scott Andrew Myers.
See also:
- iOS 7 lets you recognize facial expressions in photos.
- The planet is running out of supplies of indium, the main material for touch screens.
- Apple is working on a built-in projector for iPhone and iPad.
- Apple patents a new camera system.
