An OLED display uses a new technology called OLED (Organic Light Emitting Diodes). OLED screens are brighter, more efficient, thinner and feature better refresh rates and contrast than LCD or Plasma.
OLEDs are made by placing thin films of organic (carbon based) materials between two conductors. When an electrical current is applied, a bright light is emitted. Since the OLED materials emit light, a backlight is not required (unlike LCDs).
OLEDs in mobile phones
Mobile phones that boast OLED screens are rapidly becoming more prevalent, with over 500 million AMOLED screens produced in 2018 - mostly to satisfy demand from mobile phones. Samsung has been using AMOLEDs in its high-end phones for many years, and most phone makers are also starting to adopt OLED displays (including Apple, LG, Xiaomi, Huawei, Oppo, Vivo, Lenovo, Motorola, and others.
As Samsung, BOE and Visionox are already starting to produce foldable OLEDs (for Samsung Electronics, Huawei and Xiaomi and Nubia, respectively), AUO is not be left behind, and the Taiwan-based display maker announced it is working with clients to develop foldable OLEDs, with aims to start production in the second half of 2019.
AUO is developing an in-folding display (similar to Samsung's Galaxy Fold). According to CLSA, AUO is developing its foldable OLEDs in collaboration with Lenovo. AUO aims to produce these OLEDs in its 4.5-Gen AMOLED AFPD fab in Singapore - which commenced low-volume AMOLED production in 2013. AUO is currently producing mostly wearable glass-based OLEDs in its AFPD fab.
Last month Samsung unveiled its first foldable OLED device, the Galaxy Fold - with its inside-folding 7.3" 1536 x 2152 Infinity Flex AMOLED display. The GFold is not shipping yet - but according to Bloomberg, Samsung is already developing two more foldable devices.
One of the two devices will look like a clamshell phone (an inside-folding OLED, but with a different form factor) - and the second will fold outside, in a similar fashion to Huawei's Mate X. The clamshell phone will be unveiled towards the end of 2019, or early in 2019. The out-folding device seems to be closer to commercialization and Samsung has already produced prototypes as it considered using this design in the first generation Galaxy Fold.
In October 2018, during the company's OLED Forum in china, Samsung detailed its future OLED technology roadmap, highlighting its sensor integration technologies. Samsung's vision includes putting a fingerprint sensor, a camera, speaker (Sound on Display) and also Haptic capabilities - all under or inside the OLED display.
In the Galaxy S10, Samsung drilled a small hole in the AMOLED display around the camera module. This is quite an achievement, and Samsung's Mobile Communication VP Yang Byung-duk now ways that the company aims to develop a full-screen smartphone display that will put the camera under the OLED without a hole. Byung-duk says that this is a challenging technology - and it will take at least 3 years to develop.
Sony launched its Xperia 1, the world's first 4K OLED smartphone, at MWC 2019, and the company did not yet disclose the price or release date. Amazon now lists this new smartphone, with a $999.99 price tag (for the 128GB model). The shipping date is set at December 2019, but this is likely just a placeholder as Sony said it will ship the phone towards the end of spring (at around May).
The Xperia 1 features a tall 6.5-inch 21:9 3840x1664 AMOLED "CinemaWide" display which supportss HDR (BT.2020). The Xperia 1 also features a Snapdragon 855 chipset, 6GB of RAM, 64/128 GB of storage, a microSD slot and a triple camera. The phone is also waterproof (IP68) and it has a fingerprint sensor on the side.
Last month LG Electronics announced its G8 ThinQ with its 6.1" 1440x3120 Crystal Sound OLED. According to a new trademark filing, LG now aims to brand its CSO OLEDs as "Display Speaker".
A Crystal Sound OLED, or Display Speaker turns the flexible OLED display into high end speakers. This innovating OLED technology works for smartphones, TVs and also OLED lighting panels. In LG's trademark filing, it also hints that this technology will be used in future wearable displays.
DisplayMate posted an extensive review of the new Samsung Galaxy S10 display - the 6.1" 3040x1440 (550 PPI) flexible AMOLED. SDC's AMOLEDs are excellent displays - and it is not a surprise that DisplateMate found this newest AMOLED to be the best mobile display it ever tested.
Korea's ETNews reports that Samsung has shipped foldable OLED display samples to both Apple And Google. According to the report, the displays sent to Apple were 7.2" in size (just slightly smaller than the Galaxy Fold OLED display).
This is hardly a surprise - it's highly likely that all smartphone brands are now looking into foldable displays for next generation devices - and all leading brands are also likely to want to design prototypes and start looking at displays.
China-based TCL has unveiled a new foldable OLED phone prototype at MWC 2019. The device uses a 7.2" 2048 x 1546 AMOLED display that folds inwardly (in a similar way to the Samsung Galaxy Fold). TCL's device, however, is a prototype and not a product.