Technical / Research - Page 57

Canada's Ignis Innovation posted new job openings for their OLED TV development group, and in the job description they mention that the group is "currently working on two AMOLED television designs, targeted for mass production in 2012".

3.5-inch a-Si AMOLED prototype

IGNIS developed a-Si based AMOLEDs and reportedly RiTdisplay is starting to mass produce AMOLEDs based on this design - but these are 3.5" (320x480) panels - it seems unlikely that they'll be able to scale up to OLED TV size in such a short time frame. But it's also unlikely that either Samsung or LG Display are using Ignis technology in their upcoming OLED TVs (which use LTPS and Oxide-TFT, not a-Si).

A couple of days ago MicroOLED announced their next-generation 0.61" OLED microdisplay which features 5.4 million pixels. Today we have some more information and the product's data sheet. The most interesting info is that samples of the new products are already available - with volume production expected in 10 weeks.

It turns out that MicroOLED will offer two versions. The MDP02APFC offers full-color (using 4 sub white OLED subpixels and RGBW filters) and 1,300x1,044 resolution (just a little over SXGA which is 1,280x960). The sub-pixel pitch is 4.7x4.7 micrometre, the maximum brightness is 250Cd/m2 (typical brightness: 120 Cd/m2), the maximum contrast is 100,000:1 (typical contrast: 10,000:1) and the power consumption is 200 mW (minimum) in video mode.

There are reports that LG Display decided to built a pilot 3.5-Gen (730 × 460 mm) flexible OLED production line. They have ordered the equipment, which will arrive by 3Q 2012, and the line will become active by the end of 2012. An official from LGD is quoted saying that it will take 1-2 years to develop and verify the process and produce prototypes. The company hasn't decided on a production schedule yet.

LG Display's flexible OLEDs will use the same technology as Samsung's flexible prototypes - a polyimide coated substrate and direct-emission RGB sub-pixels (as opposed to LG's OLED TV which use WOLED with color filters).

Tanaka Kikinzoku Kogyo announced that their conductive silver ink is now available commercially, and they say they are the first company to offer such a prOduct. The silver ink is hardened using UV light - there's no need for thermal hardening, and can be used in a broad range of products - including OLED panels.

The ink needs to be exposed to UV light for around 0.3 seconds, and it then hardens instantaneously even at room temperature to form a current-carrying circuit. For a 5 µm film thickness, wiring was formed with an electric resistivity of 10^-3 ohm cm. The ink can be used on both a glass base and a flexible base (PVC or PET films).

Digitimes Research posted about Philips lighting unit, and they said that the company's goal is to reach an efficiency of 120 lm/W for their OLED lighting panels by 2019. We talked to Philips and indeed they confirm this number. Philips is gearing up to start production in their new Aachen production plant which will increase production capacity tenfold and will also lower prices considerably.

This is quite an increase from the panels Philips make today. The regular Lumiblades offer around 12 lm/W, while the Lumiblade Plus (a phosphorescent panel, developed by Konica Minolta and produced by Philips) offers 45 lm/W. We reviewed Philips' new Lumiblades recently, here's the short hands on video:

Researchers from Cambridge University and Ignis Innovation developed a new energy harvested that sits inside a mobile phone with an OLED display and harvests energy from the light that is projected to the display's sides. The researchers say that up to 64% of the light is lost in typical OLED displays - much of it projected to the edges of the display. The idea is simple - to place an array of thin-film hydrogenated a-Si solar cells around the OLED. These cells can also harvest ambient light.

The researchers made a complete system design - instead of charging the battery with the power generated (which would be quite complex) they added a supercapacitor for intermediate energy storage. They say the system achieves an average efficiency of 11% and peak efficiency of 18%, while the PV array converts around 5% of the ambient light to electricity. They say that on a typical 3.7" OLED display the maximum power output is 5 milliwatts. Useful, but not significant compared to the phone's power needs, so it's not clear whether this is worth the extra cost, size and weight.

The Holst Centre and imec announced a new high-resolution flexible OLED displays research program. This new program builds on the existing research fields such Organic and Oxide Transistors and Flexible OLED lighting. The new program aims to develop an economically scalable route to flexible AMOLED mass production, facing challenges such as high resolution, low power consumption, large area, outdoor readability, flexibility and light weight.

The partners will develop a mechanically flexible encapsulation film and TFT backplane, a printed high-efficiency OLED, new materials and processes that will allow cheaper production at better quality and driver design. They will also develop a new manufacturing equipment such as fine patterning equipment for backplanes and tools for integrated roll-to-roll manufacturing. This new program follows up on the FLAME project. Above you can see a prototype Polymer-Vision made flexible OLED made together with imec and the Holst Center.

Japan's Oji Paper developed a new microfabrication technology that can be used to enhance the light extraction efficiency of OLEDs. The idea is to use microparticle coating to form a regular pattern that is several-nanometer-wide on the surface of the metal part of the negative electrode in an OLED panel. The nanostructure turns the plasmon energy (that is sometimes released from an OLED) into light.

Oji paper says that this technology was used to improve a red OLED's light extraction efficiency by about 100%. They are now working to apply this to a white OLED.

Researchers from the University of California San Diego managed to develop "biopxels" - made from bioluminescent E. coli bacteria. The researchers managed to sync a colony of bacteria using quorum sensing. Each colony is thus a single "pixel". The researchers produced a "chip" which holds 13,000 colony-pixels (a total of about 50 million bacteria).

This technology isn't likely to lead us to biology TVs, but the researchers do hope to develop this technology for biological sensors.

Update: LG Electronics revealed the model number (55EL9600) and posted some new photos and more details on the OLED TV...

LG Display announced that they will unveil a new 55" OLED TV panel at CES 2012, and offered some more details and a couple of photos. Last month LG said that their OLED TVs will be available in the middle of 2012. The panel is only 5mm thick, and is also lighter than LCD panels. It features a 100,000:1 contrast ratio, fast refresh rates and a wide color gamut (wider than LCD, according to LG). They also say that the TV is more power efficient than an LCD TV, but they wouldn't give any details yet.

LG Display's panel uses an Oxide-TFT backplane (this was announced before). According to LG this backplane offers an identical image to LTPS panels, while being significantly cheaper. The TV uses a white-OLED with color filter design (this was the technology LGD acquired from Kodak back in 2009).