tandem architecture

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).

Samsung Display had a rather large booth at Displayweek 2024, showing its latest OLED displays and technologies. Samsung showed several displays - including foldable smartphone panels, laptop and tablet displays, two QD-OLED displays, its 9.4" round automotive AMOLED, and more.

One interesting display was a panel that combines a foldable and a rollable display, that can open up to an impressively large display. Samsung brands it as a Flex Note Extendable Display.

Yesterday Apple officially announced its 2024 iPad Pro devices, Apple's first tablets with AMOLED displays. There are two devices, a 11" model (1668x2420) and a 13" model (2064x2752). Both OLEDs offer 120Hz and 1600 nits peak brightness - and a tandem architecture. Apple brands these displays as Ultra Retina Tandem OLEDs.

The new iPad Pro 2024 devices will ship next week, starting at $999 for the 11" model. Some of the models offer a matte finish (nano-texture glass coating).

In 2022, Japan Display (JDI) announced that it has developed a "historic breakthrough in display technology" - a new OLED deposition process which they refer to as eLEAP, that is said to be cost effective and can be used to create freeform OLEDs that are brighter, more efficient, and longer lasting compared to OLEDs produced using mask evaporation (FMM).

JDI is planning to establish a 8.7-Gen eLEAP fab in China, and it is also building a smaller-scale 6-Gen eLEAP production line in Mobara, Japan. The company announced that the 6-Gen Mobara fab is advancing ahead of schedule, and production of eLEAP panels will begin before the end of 2024. JDI developed 14" laptop panels that are three times brighter than other OLEDs (at 1,600 nits), and is also targeting smartwatches, smartphones and automotive displays. JDI is also looking into adopting a tandem structure, to increase brightness even further to 3,000 nits.

In January 2024 we reported that Samsung Display and LG Display have started to produce AMOLED displays for Apple's future iPads, to be announced later this year. Earlier expectations were for Apple to order a total of 10 million iPad AMOLED displays in 2024 from both LGD and SDC, with LGD getting around 60% of the orders. 

Apple was aiming to launch the new OLED iPads this month, but have now reportedly delayed the release to May, as Samsung is suffering from low yields for the 11" AMOLED panels, mostly due to the tandem stack architecture.