Discussion: OLED lighting can exceed LED

Organic EL lighting manufacturers in the field of organic EL Technology International Symposium "OLEDs World Summit 2012" on the show said, "in theory, organic EL luminous efficiency and the same LED. The efficiency of organic LED lighting can be significantly more than LED". He said that organic EL elements in theory can achieve up to 249lm/W luminous efficiency.

According to its introduction, the theoretical limit value of the luminous efficiency of white light-emitting organic EL elements in the color temperature of 4000K and the use of single-layer light-emitting structure for the 249lm/W, using a series of 184lm/W". The theoretical limit value is the assumption that the light extraction efficiency and the internal and external quantum efficiency are all 100%. The luminous efficiency of white LED theoretical limit value of about 260lm/W. If the organic EL is single layer light emitting structure, the luminous efficiency can also be close to this value. Organic EL is also known as organic light-emitting diodes (organic LED, OLED), there is no fundamental difference from the light-emitting principle and LED. From this point of view, the luminous efficiency of the two theoretical value is not strange.

Prior to the actual production of organic EL devices, there have been examples of internal quantum efficiency close to 100%, but the light extraction efficiency of up to about 60%, has not yet paved the way to improve the theoretical path to 100%.

Moreover, Tian Yu in the comparison of organic EL and LED lighting appliances, said, even if the use of the current organic EL technology, luminous efficiency of lighting appliances can also compete with LED lighting". Tian Yi quoted the U.S. Department of energy (DOE) published in March 2010 LED technology survey report DOE MultiyearPlan pointed out that (before 2009) LED lighting luminous efficiency is only LED light source (packaging) 32.3%". Lighting bare LED light source, it will cause harm to the eyes, in order to prevent this and the use of the diffuser plate will lead to reduced luminous efficiency. The organic EL lighting is often used as a lighting panel as a lighting device, rarely cause a significant reduction in luminous efficiency.

But the future development goal of DOE's report is to increase the luminous efficiency of the LED lighting device to 62.9% of the LED light source.