Technical / Research - Page 83

Sony is showing a beautiful 4.1" flexible-rollable OLED display at SID - with 423x240 resolution (121ppi), 16.8 million colors and a 1000:1 contrast ratio. It's only 80um thick. Today they revealed some more technical details.

Sony said that the most distinctive technological feature of the panel is the organic semiconductor material "PXX (peri-Xanthenoxanthene) derivative," which Sony developed. The OTFT has a carrier mobility of 0.4cm²/Vs (four times higher than that of pentacene, which is commonly used). As a result, it became possible to use organic TFTs to form a gate-driver circuit on a resin substrate. Because there is no need to embed a driver chip, the entire panel can be folded. Sony did however embed a driver chip (it isn't easy to form a source 
driver circuit on a resin substrate) - and so the OLED on display can be folded only to one side.

NHK has improved the resolution of their organic TFT (OTFT) flexible OLED panel by four times. The flexible OLED is a 5" 320x240 (QVGA), 80ppi panel. In its 318um-wide pixel (their previous panel's pixel size was 600um) the red, green and blue subpixels are transversely arranged. Its frame frequency is 60Hz.

NHK flexible OTFT OLED panel photo

The gate insulating film was formed by a coating method, which is suited for a large-area panel. The OLED layer was formed by an evaporation method using a low-molecular phosphorescent material.

Universal Display has more news for us at SID 2010. They have already announced the new light-blue light-blue phosphorescent OLED emitter system, suitable for both display and lighting applications. Today they are presenting an all-phosphorescent white OLED to address initial commercial niche white lighting applications

UDC is showing a 15cm x 15cm OLED lighting panel using the company’s highly-efficient phosphorescent OLED technology and materials. UDC believes that this panel is the most energy-efficient performance, at this scale, reported to date. This panel emits a warm-white light with a color rendering index (CRI) of 87 and a correlated color temperature (CCT) of 3055K. It also has a luminous efficacy of 50 lumens per Watt using an optical outcoupling treatment with a modest 1.5x enhancement factor. With an operating lifetime of approximately 10,000 hours to 70% of an initial luminance of 1,000 cd/m², this panel performance has the potential to meet the requirements for a number of initial commercial niche OLED lighting applications, and is an important step toward white OLED panel performance that achieves Energy Star
targets.

Back in CES 2010, Samsung has shown a transparent-laptop prototype, with a 14" display. Today they are revealing the structure of that display. The screen has a 960x540 resolution, and a brightness of 200cd/m².

The top-emission OLED panel uses a LTPS TFT for its drive element. About 75% percent of each pixel is transparent, says Samsung, and this can be achieved by forming drive elements and organic EL elements (anode electrode, luminescent layer) on gate or source wiring. The OLED elements are made by using a metal stencil mask, and the cathode electrodes are made from a newly developed metal material.

The Printable Electronics Technology Centre (PETEC) has announced plans for a new prototyping line to support the lighting and Organic Photovoltaic sectors. The new line is targeted at industries needing large area coating capability alongside the need for reproducible uniform and low defectivity thin film coating onto glass and plastic substrates.

It is designed to be an automated batch tool based on cassette handling of samples to minimise manual intervention. The specification has been aligned with the needs of the SSL and PV industry. It will produce up to 20 samples per day with a panel size from 100mm to 200mm square. The line will have slot-die and spin coating modules, metal and organic evaporation and encapsulation.  It will enable the deposition of solution and small molecule OLED material technologies. It will target fine coating active layers of 10-200nm thinness with uniformity of +-5% across the full panel width.

Last week we reported that PolyPhotonix plans to launch a 8" 60lm/W OLED Lighting panel. They will be using this line at PETEC.

A couple of days ago, Universal Display has announced a new light-blue phosphorescent OLED emitter system, suitable for both display and lighting applications. Today they are presenting the all-phosphorescent AMOLED architecture that uses the light-blue OLED as a fourth light-blue sub-pixel.

The introduction of a light blue sub-pixel can significantly extend the operational lifetime of an OLED display and reduce the display's power consumption by as much as 33%, as compared to an RGB OLED display using a fluorescent blue sub-pixel.

Sony is showing off a new 4.1" rollable OLED display at SID 2010. The new display has a 423x240 resolution (121ppi) with 16.8 million colors and a 1000:1 contrast ratio. It's only 80 um thick...

Sony has developed an organic thin-film transistors (OTFTs) that use a peri-Xanthenoxanthene (PXX) derivative, and then integrated the OLED on the substrate.

Cymber says they are beginning to roll out lasers for OLED manufacturing, through their TCZ display division. They have already installed their first system in an unnamed customer in South Korea (probably Samsung Mobile Display. If all goes as planned, consumers could see the first OLED displays made with TCZ tools in time for Christmas), and it plans to deliver the 2nd one in another unnamed customer in China by the end of October.

One of the key innovations underlying TCZ’s OLED technology is a process that creates a uniform grid of transistors on the semiconducting material that forms a thin-film base layer on a screen’s backplane, or control layer. Each transistor in the grid controls a light-emitting diode, and each LED illuminates a single pixel. Another key innovation involves depositing one of three proprietary organic compounds precisely atop each LED to make a red, green, or blue pixel.

Universal Display has announced a new light-blue phosphorescent OLED emitter system, suitable for both display and lighting applications. Today they are giving us more information about the new material.

Universal Display’s new light-blue emitter system offers CIE coordinates of (0.17, 0.37) and a peak wavelength of 472 nm. It also provides a luminous efficiency of > 45 candelas per Ampere, corresponding to > 20% external quantum efficiency at 1,000 candelas per square meter (cd/m²). Under accelerated test conditions, this new emitter system demonstrates an operating lifetime of approximately 9,000 hours, to 50% of an initial luminance of 1,000 cd/m². These performance gains are significant, representing a 30% increase in luminous efficiency and an almost 100% increase in operating lifetime, as compared to Universal Display’s earlier-generation light-blue PHOLED emitter system.

Samsung is demonstrating a new 19" transparent AMOLED displays (with a 30% transparency), which they say is the world's largest.

Samsung are really into transparency, and may release a transparent AMOLED laptop soon.