Technical / Research - Page 59

Jusung Engineering reports that they managed to developed a a new metal organic chemical vapor deposition (MOCVD) technology to apply IGZO for use on flat panels. Jusung says they are the only company to develop an 8-Gen MOCVD IGZO tool, and that this technology will be compatible with future OLED display processes. We talked to Jusung and they say that they are already in talks with several potential clients (in Japan, China and Korea) and they hope to get purchase orders and start shipping equipment in the middle of 2012.

There are other methods (such as sputtering) for IGZO production. Sharp will soon start to produce IGZO displays in their upcoming production line, and over the past year we've seen IGZO OLED prototypes by Sony, Toshiba, AUO and other companies. Most (or all) of these prototypes have been developed using sputtering. Jusung claims that MOCVD will enable higher resolution than sputtering - indeed 4 or even 5 times higher! They also say that scaling sputtering to 8-Gen will be difficult, while their own MOCVD tool will be scalable up to these sizes easily.

Back in August Visionox officially launched their AMOLED project, which includes a 4.5-Gen production line which will start production in 2013. Today we hear that they have successfully developed a 7.6" AMOLED panel that features WVGA (800x480) resolution, 16.7 million colors, 84% NTSC color gamut and 500cd / m² brightness. Visionox says that when 30% of the pixels are lit the panel consumes 4.8W.

Visionox AMOLED pilot production line

The 7.6" panel was developed at Vixionox's Pilot line (completed in June 2010) was co-developed with the Kunshan Industrial Technology Research Institute (K-ITRI).

A few weeks ago we reported that Sumitomo Chemical began construction of a PLED material factory (which will be operational in 2012) in a several billion yen investment. These materials are aimed towards large panel (OLED TV) production. Today we have a new report that say that Sumitomo made a breakthrough in its PLED material technology - which will eventually enable production cost to be slashed by up to 50% (compared to SM-OLED based displays).

Sumitomo 6.5-inch AMOLED prototype

The annual output of their new Osaka plant will be enough to produce 4-5 million 40" OLED TVs. Sumitomo plans to offer these materials to TV makers in Japan, South Korea, and Taiwan. PLEDs (or Polymer-OLEDs, sometimes called PLED too) are OLED devices made from polymer (large-molecules) materials and are more easily adapted for printing (solution-processable) compared to Small-Molecule OLEDS (SM-OLEDs). Some companies believe that PLEDs are the best way to create large OLED panels using printing methods. You can read more about PLEDs here.

Nokia's ClearBlack Display technology has been announced in September 2010, but only now did they explained this technology fully. We knew that CBD adds a polarizing filter to a display (which can be either an LCD or an OLED) - but Nokia now tells us that the filter is placed between the touch layer and the actual display - which enables it to block incoming light and not harm the contrast or color quality. In the photo below, we can see a normal C6-01 phone with a CBD display (on the left) and the same phone without the CBD layer (on the right):

While the technology behind CBD displays is quite different to the one used in Samsung's Super AMOLED displays (which uses an on-cell touch layer) - the resulting image quality and behavior under sunlight is pretty similar in both display technologies.

Sim4tec has released a new version (v4.0) of their OLED simulation software, SimOLED. The major new addition is the FITTING modules which generates reliable physical organic material parameters like HOMO, LUMO, mobilities and traps based on simple experimental data like I-V curves.

Other new features:

• Enhanced super-fast steady-state solver for quick extraction of electrical material parameters
• New, fast steady-state solver for calculating electrical and optical key figures of complete OLEDs in a matter of seconds
• Switching of light direction for bottom and top emission configuration

OSRAM announced that they developed a new flexible OLED with an efficiency of 32 lm/W - which makes is the world's most efficient OLED lighting panel (according to OSRAM). The new panel is made on a thin steel foil with a thickness of approximately 100 micrometers - like a sheet of paper. OSRAM developed a new electrode design for this top-emitter OLED panel, which brightness is fixed at 1,000 cd/m².

OSRAM's flexible OLED research was conducted as part of the TOPAS 2012 project - the same project in which OSRAM developed the 87 lm/W white OLED panel back in June.

Apple filed a new patent that discusses using an OLED backlighting unit (BLU) for an LCD display. According to the patent filing, an OLED BLU unit may be thinner than a LED BLU and also have an improved light uniformity without using light guides. The BLU may act like a 'one large white pixel', but Apple also discusses the option that it may have several controllable 'areas' which will receive grayscale image information which may be used to modulate the light brightness (like local-dimming in full-array LED panels). Finally Apple says that the BLU will include one or more 'OLED units' bonded between two glass pieces. We're not entirely sure what they mean.

Using an OLED BLU for an LCD display has been discussed before, although it seems that it will not be a very efficient design - if you have a white OLED, why not use color-filters and not an LCD at all? This is the architecture that LG Display proposes for its upcoming OLED TVs.

Researchers from the Korea Advanced Institute of Science and Technology (KAIST) developed a flexible non-volatile resistive random access memory (RRAM) on plastic. The team used memristors integrated with high-performance single-crystal silicon transistors - which solves the problem of cell-to-cell interference while still providing the performance needed to drive the memristor cells.

This is the first time such a flexible memory is achieved, and this can be an important step towards flexible devices.

Apple filed a new patent describing a new display system which incorporates a transparent OLED on a solid white background. The idea is to conserve battery use - and when there's a need to display a white pixel, you simply switch the OLED pixel off, which then shows the white background beneath. The system also includes a switchable layer between the OLED and the white background. This layer can be either transparent or black - which will allow to see black pixels (which is not possible in normal transparent OLEDs).

Apple has filed several OLED patents in the past years. In July the company filed a patent for a 3D multiple transparent OLED displays device, and in February the company filed three different OLED patents, the main one being an OLED with an integrated touch sensor.

DuPont announced that it has signed a OLED production technology licensing agreement with a leading Asian AMOLED maker. This technology will be used to make large size OLED TV panels. We don't have any financial details on this agreement, but a leading asian AMOLED maker probably means Samsung, LG or Sony. In fact Bloomberg claims that the company is probably Samsung (which makes sense).

DuPont 4.3-inch printed OLED prototype

DuPont's nozzle-printing (or "spray-printing") technology uses a continuous stream of ink (unlike the droplets used in regular inkjet printing) to deposit OLED materials. This is a very fast process - DuPont says it can print a 50" TV in under 2 minutes, but the display isn't optimized in the sub-pixel level and is so less efficient than in other patterning technologies. But the faster throughput can lead to cheaper displays - in fact DuPont claims that this technology may make an OLED TV cheaper than an LCD TV.