OLED Lifetime: introduction and market status - Page 12

According to UBI Research, the AMOLED market reach $2.3 billion in Q1 2014, up 42% from Q4 2013 (which was a soft quarter, 36% lower than Q3 2013). Samsung Display is still of course the major AMOLED producer.

LGD's market share was only 2% - producing flexible OLEDs and 55" OLED TV panels. But UBI expects LGD's market share to expand gradually. UBI says that LGD sold 50% more OLED TVs in the quarter compared to Q4 2013 (this is by revenue, which means that shipments almost doubled as the price keeps dropping). UBI expects LGD's OLED TV sales to grow by more than 60% in Q2 2014 as Chinese TV start marketing TVs with LGD's OLED panels, and LG Electronics expand OLED TV sales to more countries.

On March 2014, Konica Minolta announced it developed the world's most efficient OLED lighting panel - at 131 lm/W. Only two months later, the Japanese company announced it developed an even more efficient panel at 139 lm/W.

Konica's new panel has an emitting area of 15 square centimeters, a lifetime of 55,000 hours (LT50) at a brightness of 1,000 cd/m² and a CRI of 81. The color temperature is 2857K.

Universal Display report several OLED technology advances at DisplayWeek. First up, the company is showing several advances in OLED lighting. UDC is presenting a new approach to make white OLEDs. The panels are based on RGB stripes, each controlled with a separate current driver. UDC says that this approach potentially improves the OLED panel performance, manufacturing yield, brightness uniformity and color-tunability.

UDC calls this new architecture "RGB monochrome striped", and they demonstrate a 15x15 cm color-tunable white OLED that features an effifacy of 63 lm/W and a color temperature of 3000K. UDC is also showing a 100 lm/W all-phosphorescent warm white OLED with a lifetime (LT70) of 60,000 hours at 1,000 cd/m². Finally, UDC is also showing a remarkable high R9 warm white WOLED with CRI of 96.

IGNIS Innovation announced today that they are going to collaborate with Shenzhen China Star Optoelectronics Technology (CSOT) to develop a 5.5" HD AMOLED panel that will use Ignis's MaxLife Lite driving scheme.

The AMOLED panel will be produced by CSOT using an LTPS backplane. Ignis's MaxLife Lite will enable high yields, low cost, low-power consumption, and long life time. CSOT hopes that Ignis' technology will enable them to quickly ramp up production.

Fraunhofer COMEDD is looking to advance flexible OLED lighting device lifetime, and towards that goal the German institute developed flexible OLED lighting panels on flexible glass substrates. COMEDD reports that flexible glass can enable curved panels that has high OLED lifetime - much higher than can be obtained with polymer-based encapsulation and substrate technologies.

Fraunhofer developed those new panels on their own Roll-to-Roll R&D line in collaboration with Von Ardenne (on the development of process equipment) and Nippon Electric Glass (they provided the "G-Leaf" flexible glass rolls). The G-Leaf glass is less than 35 um thick and can be used in roll-to-roll processes.

During a conference in Korea, LG Display's OLED technical strategy team leader Lim Joo-son said that the company's WRGB technology does not place any limits to the size of the OLED TVs they can make, and once the M2 goes into operation, the company will be able to produce 110" TVs.

LG Electronics 77-inch OLED TV prototype

LG also managed to increase the pixel density, and can now produce 8K (7680x4320) panels - but they admit that the smaller aperture in such panels limits the lifetime and they urgently need to develop longer lasting OLED materials.

Researchers from Kyushu University (led by Chihaya Adachi) developed a highly efficient blue OLED TADF (Thermally Activated Delayed Fluorescence) emitter that achieves almost 20% external quantum efficiency - similar to the best blue phosphorescent emitters.

TADF OLEDs are free from the heavy metals used in phosphorescent emitters and so they could be cheaper and better for the environment. The main problem with blue phosphorescent OLEDs is the short lifetime which still makes it impossible to use them in commercial applications. The new TADF blue OLEDs has about the same lifetime as the blue PHOLEDs, but researchers are hopeful that it will be easier to improve the lifetime of the TADF emitters.

LG Chem announced the world's largest OLED lighting panel at 320x320 mm (and it's only 1 mm thick!). The N6SD30 features 60 lm/W, 850 lumens brightness (max 1,000), a high CRI (>90) and a color temperature of 3000K.

The lifetime of the N6SD30 is 40,000 (LT70) at 3,000 cd/m². LG Chem says they managed to extend the panel's lifetime (compared to their older panels) mainly by using the company's own  Face Seal encapsulation technology. In fact, LG Chem upgraded all of their OLED panels to feature this new encapsulation and so all of their panels now feature 40,000 (LT70) lifetime hours.

The SID Display Week, the world's leading display industry showcase is scheduled for June, but the organizers already published the list of papers to be presented in this show. Hiding in this long list of technical achievements and research projects are some interesting new OLED developments. So here's some of the achievements to be announced during the show (at no particular order).

TCL's China Star Optoelectronics Technology (CSOT) managed to fabricate a 7" QVGA (320x240) flexible PMOLED display. The display uses a thin PEN substrate, processed at Gen-4.5. The company also proposes a design for a 14" QVGA PMOLED panel. CSOT also developed a 31" Full-HD AMOLED panel that uses a IGZO backplane. The 31" direct-emission panel was produced on a Gen-4.5 glass substrate using FMM.

In October 2013 Mitsubishi Chemical and Pioneer announced that they plan to start producing printed OLED lighting panels in 2014. Now Verbatim announced that it will bring an OLED panel produced using a "web coating process" to the Light + Building exhibition in April. Verbatim will also demonstrate a flexible OLED lighting panel for the first time.

We don't have any more information regarding Verbatim's new panels. In October 2013, however, Pioneer and Mitsubishi said that their panels use coating only for the bottom layer, while the emissive and top layers are deposited using VTE.