Market rumors surrounding Apple’s interest in OLED technology have resurfaced this week. The company has applied for an OLED patent with integrated thermal sensors, according to an article by Patently Apple. Although, Apple CEO Tim Cook has been repeatedly quoted as showing no interest in OLED technology in February during the Goldman Sachs Conference, the company just cannot ignore the advantages OLED technology presents in wearable electronic devices, such as the iWatch.

The Apple patent noted that while OLED emits its own colored light, the displays are thinner and lighter than lighting that requires backlighting and offered viewing advantages and color saturation. However, OLED displays appearance might degrade over time through age and use. Their colors and brightness also changes over time, especially for blue OLEDs that tend to deteriorate at a much faster rate than others.  Heat can also accelerate aging in OLEDs. 

While OLED displays do not require backlight, other electronic components and devices might be placed underneath the display. Some of the components underneath the display include processors, radio transmitters, batteries, speakers, cameras, and others. Some components especially processor or radio transmitter might warm up during extended use, and heat up certain parts of the display. Heat might be distributed unevenly on the display, as some components might be warmer than others.  

Operating temperatures can also affect OLED performance, especially for red OLEDs as brightness might decrease due to increased temperatures. In addition to accelerated aging, images might become distorted. Controllers might make changes to compensate for shifts in brightness and color, but the deviations in brightness and color might vary across different regions of the display. 

In response, Apple has applied for a thermal sensor patent that is integrated into the display to determine present temperature, temperature history, and or a thermal profile of individual OLEDs or zones of OLEDs that control signals to the OLED or zones. OLEDs can be readjusted to compensate for temperature and or thermal aging. Please click link for further details.