Power consumption - Page 47

An interesting Inquirer article, discussing the differences between OLEDs, LCDs and Plasma displays.
"In general, OLEDs deliver brighter images, higher contrast ratios, wider viewing angles and, without the need for a backlight, require less power to run. This makes them ideal for phones, notebooks etc. But we are here to talk about big screens that will be plugged in so forget power savings. Even better, OLEDs will allow for even thinner screens - around three centimetres - and are cheaper to produce than LCDs because they use less materials and the polymers can be "printed" onto plastic or glass sheets using a process similar to inkjet printing. Theoretically, they will be cheaper to produce and so should be cheaper to buy."

Cambridge Display Technology (CDT) announced that the EU-funded STEPLED project has concluded - with "outstanding success". The STEPLED project was undertaken with the aims of understanding the science which controls the spin states of polymer-based OLED (PLEDs), critical to developing more power efficient displays.

The STEPLED project focused on establishing high efficiency materials using high singlet-ratio fluorescent polymers, but also worked on soluble phosphorescent emitter. CDT said that STEPLED achieved the production of a standard two-layer device structure with an external quantum efficiency (EQE) of 6%. This has been described as 'outstanding', being almost twice the efficiency of previous materials. The impressive performance was achieved using red emitting polymers, typically the lowest efficiency color in RGB displays.

Universal Display announced a new $750,000 SBIR Phase II project from the US Department of Energy (DOE) to develop light extraction technology for energy-efficient, solid-state lighting. The new project is titled "Novel Light Extraction Enhancements for White Phosphorescent OLEDs".

Extraction efficiency defines the amount of generated light that can be extracted, or emitted, from the device as useful light. In current OLED panels about 20% to 30% of generated light is effectively extracted as useful light.

This is the second $750,000 OLED lighting efficiency project awarded to UDC this month, the first one was about lowering the OLED device voltage.

Universal Display was awarded a new $750,000 Department of Energy (DOE) SBIR II contract to lower their white phosphorescent OLED device operating voltage. The program, titled "Low Voltage, High Efficiency White Phosphorescent OLEDs for Lighting Applications" is a continuation of a DOE SBIR Phase I program awarded in 2003.

A lower voltage is important because it leads to reduction in power consumption.