Low-Temperature Polycrystalline Oxide, or LTPO, is an OLED display backplane technology developed by Apple. LTPO combines both LTPS TFTs and Oxide TFTs (IGZO, Indium Gallium Zinc Oxide). LTPO is applicable for both OLED and LCD displays, actually, but this backplane technology is likely to be used exclusively in high-end OLED displays
In LTPO, the switching circuits are using LTPS while the driving TFTs will use IGZO materials. This could lead to a power saving of around 5-15% compared to the currently-used LTPS backplanes. The main drawback of LTPO, however, is that the IGZO TFTs are larger and so the display density may be compromised.
In September 2014 Apple introduced the world's first device to use an LTPO backplane - the Watch Series 4. Compared to the current-generation Watch, the new series has a larger AMOLED display - 1.78" 448x363 on the 44 mm watch and a 1.57" 394x324 one on the 40 mm model.
The latest LTPO OLED news:
Towards the end of 2021, it was reported that Visionox has finalized its LTPO R&D project and is ready to start producing LTPO OLED displays. The company now officially launched its first LTPO AMOLED dipslay, that can offer a dynamic refresh rate, from 1Hz to 120Hz. Visionox expects the first phones to adopt these new displays to be released soon.
The new LTPO AMOLED displays are produced at Visionox's Hefei 6-Gen flexible AMOLED line. This is the first LTPO OLED displays produced in China (previously only Samsung and LG produced such advanced panels).
BOE has been aiming to supply OLED displays for Apple for a long time. In 2020 BOE did not pass Apple's OLED quality test for the iPhone 12 , but later it it did manage to enter Apple's supply chain, only for aftermarket (refurbished models) 6.06" LTPS AMOLED displays.
According to reports in Korea, for Apple's 2014 models, which will be introduced in 2022, BOE aims to supply similar panels (to standard models). BOE is also aiming to be the producer of Apple's iPhone 15 Pro series in 2023. The company is looking to introduce LTPO technology at its B12 AMOLED line at Chongqing, the line which has only recently started production.
According to reports from China, Visionox has finalized its LTPO R&D project and is now starting to produce LTPO OLED displays. This will enable the company to compete with Samsung and other leading OLED producers for the high-end smartphone display segment.
Low-Temperature Polycrystalline Oxide, or LTPO, is an OLED display backplane technology developed by Apple. LTPO combines both LTPS TFTs and Oxide TFTs (IGZO, Indium Gallium Zinc Oxide) to enable variable refresh rate displays, and power savings of up to 15%. LTPO AMOLED displays are widely used today in high-end smartphones and other mobile devices.
DSCC posted an interesting article, comparing the production costs of OLED vs mini-LED panels for IT. DSCC estimates that for tablets and notebooks, a tandem structure will be used, and the panels will be based on rigid substrates.
In the chart above you see a production cost comparison, between 2021 and 2025, for 12.9" panels. DSCC looks at two OLED production options: a tandem OLED panel with an LTPO backplane produced in a 6-Gen fab, and a similar panel that uses an Oxide-TFT backplane and produced in a larger 8.5-Gen fab. As you can see, OLED panels are more cost effective, and will remain so throughout the forecast period.
According to a new report from Korea, Samsung has decided to build a new flexible OLED 6-Gen (1500x1850 mm) production line (A4E, although this could be a tentative name), which will be located at Samsung's Asan production complex.
The new fab will have a monthly capacity of 30,000 substrates. The first phase (15,000 substrates) will enter production by the end of 2022, and the second phase a year later. Total investment is estimated at over 1 trillion KRW (around $854 million USD).
A few days ago we posted that Apple has reportedly decided to delay its iPad OLED launch to 2023, and the company canceled its current joint development project with Samsung Display, as SDC could not develop what Apple wanted - a tandem stack structure, which would have improved the lifetime and performance of the AMOLED display.
According to a new report from Korea, LG Display is also developing a tablet display for Apple - a 12.9" AMOLED panel. LG's iPad display will be ready for mass production by 2023-2024, and it will use a tandem (2 stacks) architecture on an LTPO backplane. As SDC's project is canceled, it is likely that LG's 12.9" will be the first OLED adopted by Apple's tablets.
Our friends at DisplayMate posted an in-depth technical review of the iPhone 13 Pro Max display. The 6.7-inch 1284x2778 10Hz-120Hz 1200 nits LTPO AMOLED receives DisplayMate's highest display performance grade of A+.
DisplayMate says that the new display outperforms the display adopted by Apple in last year's iPhone 12 Pro Max. The iPhone 13 Pro display's new adaptive 120Hz refresh rate which results in a 25% boost to power efficiency. The new display is also brighter by 27% and enjoys a higher absolute color accuracy. The size of the notch was also reduced by 20%.
Apple introduced its latest iPhones, with four models, all featuring AMOLED displays. We'll start with the iPhone 13 which features a 6.1" Super Retina 1200 nits 1170x2532 (460 PPI) AMOLED display. The iPhone 13 mini offer similar specifications, with a 5.4" 1080x2340 1200 nits AMOLED (476 PPI) displays.
According to reports, Vivo will soon release its latest IQOO smartphone (IQOO 8 Pro). The phone will use an AMOLED display produced by Samsung Display. This panel, in fact, will be the first one to adopt Samsung's latest E5 OLED stack.
We do not have any information on this new stack, but OLED companies keep improving the material stack to enable higher efficiency - and sometimes to increase the color gamut, reduce costs or improve other performance points. Hopefully Samsung will announce the E5 stack officially soon.
Samsung Display has recently announced two design wins for its smartphone LTPO AMOLED displays - the Oppo Find X3 series and the OnePlus 9 Pro. Both adopt the same 6.7-inch 1440x3216 120Hz HDR10+ (1,300 nits peak) LTPO AMOLED display.
Samsung also announced that in the past the company's priority was to improve the image quality and the design of its OLED displays. Moving forward, SDC will focus on lowering the power consumption of its OLED displays. SDC will do so by developing low-power materials and "optimizing power-efficient technologies".