Technical / Research - Page 99

IGNIS Innovation unveiled a prototype display using its Driver IC  MaxLife. The MaxLife solution compensates not only for the thin film transistor (TFT) degradation, but also for OLED as well.

IGNIS showed its prototype of a cutout of a 32 1080p HDTV, with an operating device lifetime of 75,000 hrs and no image burn-in over that period, which is equivalent to 20 years when watching for 10hrs/day.

The growth of the AMOLED industry has been constrained due to the technological hurdles associated with achieving a truly reliable, uniform and scalable TFT backplane. Our MaxLife platform now enables our customers, the display manufacturers, to accelerate their market introduction of large, visually stunning and affordable AMOLED HDTVs and other large area applications in the very near future, said Paul Arsenault, President and CEO of IGNIS.

Bayer MaterialScience AG, a unit of Bayer AG, signed a technology and patent license agreement with Add-Vision. Bayer will be able to manufacture and sell flexible Polymer based printable OLEDs. 

Bayer says that the technology is an important component for many applications in the coming years - such as active packaging and labels, gift cards, electronic toys and games, promotional products or point-of-sale signage.

Financial details have not been disclosed.

Scientists from the RIKEN Advanced Science Institute in Wako have developed a way to eliminate precise doping limits from the OLED manufacturing process. By using a metal dopant containing molecular groups that block the self-quenching interactions, the scientists have, for the first time, fabricated high-efficiency OLEDs with a wide range of doping concentrations.

Hou and colleagues modified a phosphorescent iridium metal complex with a class of molecules known as amidinates. These molecules bind to iridium through a nitrogen atom that localizes electrons near the center of the metal complex. Bulky carbon groups on the edges of the complex are inert and prevent the materials from attaching and self-quenching their phosphorescence.

Corning is showing their latest Silicon-On-Glass (SiOG) technology. SiOG is used to transfer a thin-film of silicon into a display substrate. SiOG is scalable, and currently Corning can make it on a Gen2 substrate, Gen4 by the end of the year.

Corning SiOG prototype

The SiOG process would permit the fabrication of stable OLED pixel switches with higher yield and much greater performance than LTPS, and on larger substrates. Corning claims that costs will be lower, because this enables manufacturers to integrate the circuitry on the display substrate easily. 

Some panel makers are already trying this out, and hopefully we'll see prototype OLED displays based on SiOG by the end of 2009.

Universal Display and Samsung Mobile Displays present advances in green Phosphorescent OLEDs at SID. This new material will be used in both hand-held devices and OLED TVs, extending lifetime and efficiency. UDC's red materials are already used in Samsung's AMOLED displays, and it's likely that we'll see Samsung use their green materials as well.

The companies showed a highly-efficient, green
UniversalPHOLED material that has been used in a top-emission PHOLED
device architecture. Using this approach, they achieved two
milestones. A green PHOLED with NTSC color at CIE(0.20, 0.73), high
luminous efficiency of 110 candelas per Ampere (cd/A), and a low voltage
of 3.6 V at 3,000 candelas per square meter (cd/m2) was
achieved.

A second device structure using this green PHOLED material
system also achieved an ultra-high luminous efficiency of 160 cd/A along
with CIE(0.28, 0.69) and low voltage of 3.8 V at 3,000 cd/m2.
These compare to a standard bottom-emission device with CIE(0.33, 0.62)
and 52 cd/A using this same green PHOLED material system. Replacing the
green fluorescent OLED material typically used today in an AMOLED with
this new green PHOLED can result in a significant 37% power savings.

The operational lifetime for this green PHOLED material system is also
very good. A bottom-emission device using this material system offers >
300,000 hours to 50% (extrapolated) and 15,000 hours to 90% of the
initial luminance of 1000 cd/m2 (defined as LT90). With these
top-emission devices, the LT90 lifetime is 28,000 hours and 6,400 hours,
respectively, for the 110 cd/A and 160 cd/A devices.

3DIcon filed a patent for a high-resolution projection screen that could replace current cinema and other existing reflective display screens.

Their idea uses an OLED display driven by any front projection system to produce high-image-reproduction quality, brightness under ambient light with high contrast, and exceptional color fidelity.

In addition to the new OLED TV panels, Samsung Mobile Displays is showing new smaller mobile OLED displays. These range from 3.2" to 7". The 3.2" is the one with 310ppi, reported earlier. Actually on their site, they list panels ranging from 2.2" to 5".
 

Samsung are also showing 4.82" and 12.1" transparent displays, ID card OLEDs and other displays.

Universal Display and the Flexible Display Center at Arizona State University has announced a significant milestone towards a manufacturable flexible OLEDs. The new display is the first a-Si:H AMOLED display to be manufactured directly on DuPont Teijin’s polyethylene naphthalate (PEN) substrate.

The companies will be showing a 4.1" monochrome QVGA flexible OLED at SID. This display has the same brightness as normal displays with extremely low power consumption. The flexible backplane display was manufactured at the Flexible Display Center utilizing a 180°C thin film transistor process. The FDC’s facility implements traditional flat panel and semiconductor tools and processes to achieve flexible displays, enabled by its proprietary bond-debond technology to secure the plastic substrate to a rigid carrier during manufacture.

Wuhan National Laboratory for Optoelectronics (WNLO) in China say they developed new OLED display materials that are "quite something" in terms of light efficiency and chromaticity. We don't have any more details yet...

A few years ago, lifetime was the biggest issue with OLEDs, but it seems companies are showing very rapid advances. Dupont announced today that they developed new (third Generation) printable, solution process OLED materials.

The Green Gen3 material has over one million hours lifetime (that's over 100 years of constant use!) with 25 cd/A efficiency. The color coordinates are 0.26, 0.65. 

The light-blue Gen 3 (color coordinates 0.14, 0.12) has 38,000 hours from 1000 cd/m2, efficiency of 6.0 cd/A, and a lifetime of 38,000 hours. A deeper blue (color coordinates 0.14, 0.08) was developed with 7,000 hours. Due to its deep blue color, the lifetime of this material at the luminance required for a 200 cd/m2 display is calculated to be approximately 41,000 hours. 

The Gen-3 red has a lifetime of 62,000 hours, current efficiency of 13 cd/A, and color coordinates (0.68, 0.32).