What is an OLED?
OLED is a light-emitting diode built from thin films of organic electroluminescent material sandwiched between electrodes. Since the materials are luminescent, they produce light when the current is run through them. No other display technology creates light directly like this: LCDs use color filters and light-blocking liquid crystals above a light-creating backlight. Plasmas use UV light created by igniting pockets of gas to excite phosphors.
This means that OLED screens are thinner, lighter, more efficient and offer better performance and color quality than other existing technologies. Each pixel can be shut off, providing absolute black and amazing contrast ratio.
OLED televisions are the newest technology in the TV world. They deliver the best picture quality available today, outdoing LED LCD. But on top of being thinner, lighter and more efficient than other TVs, they can also boast a curved form.
Curved OLED TVs hold unique advantages. It can enhance the viewer’s immersive experience with its curved form, as the screen "wraps around”. The curved screen has a curved trajectory similar to a person’s ‘Horopter Line’ allowing the maintenance of a constant focus.
Another advantage of a curved TV is that the distance from the viewer is constant (unlike a flat TV in which the middle is closer than the edges). This means that in a flat TV there's a subtle image and color distortion which does not occur in a curved panel. The larger the flat screen and the closer the distance from the screen, the distortion becomes more noticeable.
A curved screen also feels larger and brighter compared to a flat TV. This, again, enhances the viewing experience. It is said that a viewer will feel that the size of a curved TV screen is larger than its actual size. Curved OLED TV also feels brighter because the light coming from the screen is focused on the center of the screen.
One final, and crucial advantage, is reduced reflections. The curved display eliminates reflections from ambient lighting on the sides, and it also reduces specular (mirror) reflections.
Nonetheless, voices arise arguing the disadvantages of curved OLED TVs: there is a claim that in order to get the benefit of a wraparound image, you need to be sitting in a pretty specific place. That sweet spot can be very small, possibly fitting only one viewer. Other faults arguably include limitation of viewing angles, elevated prices and, of course, looking less attractive mounted on a wall.
Curved TV launched at around 2013, but quickly fell out of fashion - and today very little curved TVs are sold, if at all.
Bendable OLED TVs
When people actually considered buying curved TVs, flexible OLED makers started to discuss the option of building bendable OLED TVs - a novel concept that allows a shift from flat to curved screen and vice versa at the press of a button. This enables viewers to enjoy both the flat and curved experiences in one set, encompassing both OLED’s superior image quality and the immersive experience of a curved TV. It can be neatly attached to a wall in its flat form, but curved at will to grant the ultimate viewing experience.
The bendable OLED TV market
While bendable TVs are quite cool, following the falling out of grace of curved TVs at around 2015, TV makers stopped discussing and developing bendable TVs.
In January 2014, LG unveiled a bendable 77’’ OLED TV, that can change from flat to curved (using a "combination of water and motors" - according to company statements). When at full curve, the curve is eight centimeters in total. LG said it will release a bendable OLED TV in 2015 - but this never materialized and LG evidently stopped developing the technology.
In 2014 Samsung also showcased a 55’’ bendable OLED TV prototype, and also an 85’’ bendable model that might be an OLED. Samsung pulled out of the OLED TV market later, though (it is set to return with its QD-OLED TV technology in 2019 - but it is highly unlikely it will ever offer a bendable TV).
Rollable OLED TVs
While bendable OLED TVs seem to be out of focus at this stage, a more promising technology is rollable OLED TVs. In 2017 LG Display demonstrated a 77" flexible and transparent OLED display for the first time, and in early 2019 LG Electronics announced the Signature 65" OLED TV R - and will release this TV commercially by the end of the 2019.
The latest bendable OLED TV news:
LG already announced it will be showing several new OLED TV models at CES (including new 55", 65" and 77" models), but today at CES the company unveiled a bendable 77" 4K OLED. As was speculated last month, this panel can change from flat to curved using a "combination of water and motors" (whatever that means).
Engadget says the new TV is gorgeous. They were told by LG that they actually plan to ship this TV to the US soon - at H2 2014 or maybe at the beginning of 2015. It'll be interesting to see how all this bending effects the OLED structure. The TV anyway moves 7.5 cm to bend (it's eight centimeters narrower in total at full curve).
In January 7 CES 2014 will begin, and it'll be very interesting to see what kind of new OLED products and prototypes will be launched during this exciting event. Highlights from CES 2013 included LG's OLED TV launch, Samsung's YOUM flexible OLED launch and 4.99" FHD mobile OLED (which was later adopted in the GS4) - and finally Sony's and Panasonic's 56" 4K OLED prototypes.
But what should we expect from CES 2014? So first, let's look at OLED TVs. LG and Samsung are bound to show their current flat and curved 55" OLED TV products at CES, and LG will most likely bring their 77" curved UHD OLED prototype, but we do not expect them to launch this as a product yet. The two Korean companies are quite likely though to unveil ready-to-market 4K OLED TVs, curved and flat. Samsung already showed a 55" 4K OLED prototype at IFA 2013.
Back in May, The US PTO granted a new patent to Samsung that describes a bendable OLED TV. The idea is that you can use a remote control to bend the television so you'll get a better viewing angle. The TV will include special software that adjusts the image so it is not distorted by the bending. Today the Korea Times reports that Samsung will unveil a prototype bendable OLED TV at CES 2014 (January 7). LG will also unveil a similar unit.
The report does not include more technical information, they only say that the the display size will be "huge". The OLED TV will have a plastic substrate and a back panel that can deform the display. It is possible that SDC will only unveil their prototype in closed meetings.
The US Patent Office granted Samsung a new patent (#537228) that describes a bendable TV. The idea is that you can use a remote control to bend the television so you'll get a better viewing angle:
Samsung says that this TV uses a flexible display panel (probably an OLED TV, but it is not mentioned in the patent) and a back panel that can deform the display. In addition, the whole TV sits on a unit that can be rotated. The TV will include special software that adjusts the image so it is not distorted by the bending.
The Korean government is funding a new program ("Future Flagship Program") that will develop transparent and flexible OLED technologies with an aim to produce ultra high-definition 60" flexible OLED displays by 2017. The project will be led by LG Display, and will also include equipment-maker Avaco.
The Korean Ministry of Knowledge Economy is spearheading the program, and they say that this technology may have a large impact on the Korean economy, creating 840,000 jobs and $56 billion in yearly exports. It will also help to widen the technological gap between Korea and China in the display sector. The Korean government chose several key technologies that will help to further develop the industry, and OLED is one of them.
Sony published an interesting interview with their display unit team about rollable OLED displays. Back in May (during SID 2010) Sony unveiled a new 4.1" rollable OLED display (with 423x240 resolution at 121ppi, 16.8 million colors - and the whole thing is just 80um thick). In the interview, Dr. Kazumasa Nomoto reveals that Sony's end target is a rollable large-screen OLED TV: "The time will come when the very idea that an enormous black box (TV) was ever placed in rooms will seem strange."
In the interview, the team discusses the new technologies that Sony created for this new display. First was a new Organic TFT based on a new material: a peri- Xanthenoxanthene (PXX) derivative (this took Sony 5 years to develop!). Sony also developed a flexible gate driver circuit. Finally, an insulating layer for the O-TFT and OLED materials using flexible organic materials. Those three technologies enabled sony to create a rollable video display.