Remember when LG stunned the world at CES 2017 with the introduction of its Wallpaper series of TVs? They were so thin they could be mounted on your wall alongside your picture frames. The TV wasn’t wallpaper thin, but thin enough to mark a major milestone in the development of home entertainment systems.
LG made headlines earlier this year when they unveiled the world’s first rollable TV at CES 2019. The LG Signature OLED TV R9 boasts 4K HDR, an LG α9 Gen 2 Intelligent Processor, and a 100W 4.2-channel Dolby Atmos sound system. But the real show-stopper at this year’s CES is its rollable 65” OLED display.
So how does a rollable TV work? In this post we’ll dive into the technologies that make a 4K rollable TV possible.
What is an OLED?
Before you can understand how a flexible TV screen is even possible, one must first understand the inherent advantages of OLED technology. Conventional LCDs (liquid crystal displays) and LED displays require a backlight to function—even when you’re viewing the color black on your screen, light is still technically being emitted from those pixels.
OLED is short for organic light emitting diode. It consists of an organic layer sandwiched between two electrodes (at least one of them transparent) that emits light in response to a current—eliminating the need for a backlight. When an OLED pixel displays black, it is truly black because the organic layer has ceased to emit light. This results in darker blacks, whiter whites, and better contrast overall.
Inside the rollable OLED display
The elimination of the backlight does more than just improve the contrast of your images. OLEDs are also inherently lighter, thinner, and more flexible—allowing them to be deposited onto a variety of substrate materials. This allows designers to be more flexible with display form factors.
The organic materials in OLEDs are highly susceptible to damage when exposed to water or oxygen. The core technology behind LG’s rollable OLED display is likely OLED thin-film encapsulation (TFE) which involves alternating organic layers with protective inorganic layers which serve as barriers to moisture.
How does a rollable TV work?
While much of the technology that goes into LG’s rollable TV is proprietary, here’s what we know about the device.
The bulk of the TV hardware, including the α9 processor, is packaged in its base which doubles as a Dolby Atmos speaker. A proprietary connector links the rollable screen to the TV’s internals.
The screen itself is supported on the backside by a series of interlocking bars that run the width of the screen. This prevents the screen from rolling in an unintended direction, while allowing the screen to stand rigid when extended.
Further support is provided by a frame guide that extends with the screen and folds neatly back into the box when retracted.
LG’s rollable TV boasts three viewing modes: the full 65” display, a “line view” where it sits partially emerged with audio controls and other diagnostics on display, and zero view where the base speaker is all you see.
Rolling the screen makes the TV easier to store and opens up new possibilities for how consumers design their living spaces—eliminating that ominous black mirror from your living room.
LG’s rollable TV represents the pinnacle of flexible circuit design
As LG has yet to announce an official release date for the LG Signature OLED TV R9, it will be some time before the hobbyist community is able to peek under the hood of the world’s first commercially viable rollable TV. One thing that is for certain, however, is that flexible circuit technology has come a long way.