tandem architecture

According to a new report by Business Korea, LG Display is finalizing the development of its 3rd-gen tandem-stack automotive OLED technology, and aims to start mass producing these panels by 2026. LGD believes the new panels will improve the brightness and efficiency of its OLEDs by 20% (compared to its current 2nd-gen tandem OLEDs).

LG Display believes it is leading the industry with its tandem OLED technology (and we tend to agree) and it hopes to accelerate its technology development to widen its lead. LG Display is enjoying a lead in the automotive display market with its OLED solutions and has already achieved design wins with many companies, including Genesis, Mercedes-Benz, Cadillac and GM.

DSCC says that the OLED materials market will reach $2.12 billion in 2024, rising 24% over 2023. The market will continue growing at a 6% CAGR until 2028, reaching about $2.7 billion. DSCC details the revenue split between single-stack, tandem and multi-stack panels, saying that materials used in tandem OLED panels will grow at a fast rate of 30% CAGR from 2024-2028. 

The leading materials makers by revenue in 2024 will be UDC, DuPont, LG Chemical and Samsung SDI, holding a market share of 51% together. DSCC says that Chinese materials makers will increase their market share in the future. 

OLED displays have been gaining popularity rapidly, and are already the dominant smartphone display technology. OLEDs are also the display technology of choice in the smartwatch market, making inroads into the TV, monitor, laptop and tablet markets. The future of the OLED industry looks bright.

In recent years, the focus of the industry, beyond increasing capacity and reducing production costs, has been improving the performance of OLEDs in the areas of display brightness, efficiency, and lifetime. Brightness is required in many applications - from TVs (for HDR and to view in ambient lighting) through smartphones (outdoor viewing) to automotive, and efficiency is a plus in any scenario (but mostly in mobile displays). Display lifetime is already good enough for many applications, but in some cases (like automotive, and IT displays) it is critical. These three properties usually go together - if you can make more efficient OLED displays, you can drive them at a lower current to achieve the same brightness, and so lifetime increases, or you can achieve higher brightness, etc. 

Since Samsung started mass producing AMOLED displays in 2007, most people believe that the company is not only the leader in OLED production capacity, but also in the performance of its displays. In most cases, Samsung has been the first company to develop and manage to mass produce the most advanced OLED displays, and the first to adopt the latest OLED materials, architectures, and processes.

There are some signs that this could be changing, although honestly it's a bit too early to know. In May 2024, Apple launched its first OLED Tablets, and according to reports, Apple chose LG Display as its main supplier, ordering around 60% of its iPad OLEDs from LGD (with all of the 13" model orders going to LG), and the rest from Samsung. Later it was reported that Apple had to delay the introduction of its 2024 iPad Pro devices as Samsung faced low production yields and could not deliver displays in time.

LG Display says that it has started to mass produce tandem OLED laptop panels, the first company to do so. LGD says its tandem architecture double the lifetime of its OLEDs, reduce power consumption by up to 40%, and enable up to three times the brightness.

LGD has been producing tandem OLED displays since 2019, mainly for the automotive industry. This expertise has enabled it to be Apple's main tandem OLED display suppler for its 2024 iPad Pro devices, and now to be the first one to produce tandem laptop panels. 

According to a report from Korea, LG Display has started to produce 13.4" tandem AMOLED panels for Dell, to be used in the upcoming 2024 XPS 13 laptop. LGD will produce 100,000 such panels for Dell at its E6 production line (the same line used to produce Apple's iPad Pro displays).

The tandem OLED displays will enable longer lifetimes, and also increased brightness / efficiency. Interestingly, Dell says the displays will only feature a brightness of 400 nits. The full display specification: 13.4" 3K+ (2880x1800) 60Hz 400 nits AMOLED panels. 

China-based Tianma had an impressive booth at Displayweek 2024, showing numerous OLED and microLED displays and prototypes.

For the automotive market, Tianma showed three new display prototypes. First up is a 13" slidable OLED, with an embedded touch panel, aimed towards car dashboards or center controls.

Japan's Semiconductor Energy Laboratory (SEL) demonstrated its latest OLED microdisplay technology at Displayweek 2024. The 1.5" 3840x2880 (3207 PPI) display achieves a brightness of 15,000 by using a tandem architecture and a direct-emission design. The OLED deposition was performed using photo-lithography. 

This is an impressive display, with very high brightness. It surpasses LGD's 10,000 nits microdisplay also shown at Displayweek, which uses a white-OLED with color filter design, and a microlens array. It matches eMagin's 15,000 nits microdisplay, demonstrated back in 2023 - which is a single stack device.

TCL CSOT demonstrated its latest displays, technologies and prototypes at Display Week 2024. The company is focused on inkjet printing technologies, and a lot of the displays on show were indeed printed.

So first up, we TCL demonstrated a 14" 2880x1800 400 nits 30-120Hz ink-jet printed LTPO AMOLED display. The display is produced on a glass substrate, with thin film encapsulation (a 'hybrid OLED').

LG Display demonstrated its latest OLED display prototypes and commercial panels at Displayweek 2024. The company showed flexible panels, automotive displays, transparent OLED, gaming monitors, a 10k nit microdisplay and more.

So first up, LG Display shows its automotive Advanced-Thin-OLED (ATO) displays, which are produced on glass substrates and use a tandem structure. These OLEDs are lower in cost compared to LGD's flexible automotive p-OLED panels, but still enable low-weight and thin profile, and the excellent image quality of an OLED display. The smaller display was a 12.3" 2400x900 (209 PPI) 1,000 nits panel, while the other panel was larger at 17" 1920x2560 (188 PPI).