University of Utah, new achievements: 25% is the upper limit of OLED efficiency

University of Utah scientists Christoph Boehme and John Lupton latest research results show that OLED get high luminous efficiency is not as easy as imagined. According to the study, OLED was previously thought to be the most capable of converting 63% of the electrical energy into light energy, rather than thermal energy, and now it appears that OLED's photoelectric conversion rate is only about 25%. The research has been published in the August 17th issue of the Journal Nature Materials.

Lupton said that this is the first time someone to do the basic OLED quantum mechanics research, this is a hard work. OLED is one of the most important luminescent materials because they are cheaper and easier to manufacture than inorganic LED (including inorganic materials such as gallium, arsenic, indium). The inorganic LED photoelectric conversion rate can reach 47% -64%, but the high cost limits its development.

In the past for a long time, the industry generally believe that 25% is the upper limit of the efficiency of OLED, but in 2001, some physicists in the University of Utah Nature magazine published an article that OLED efficiency is expected to reach 41%-63%.

However, the new study suggests that the upper limit of 25% may be true, at least for pure MEH-PPV, which may be true for other materials. Perhaps the efficiency of organic semiconductors doped with other chemicals may be above 25%, but Boehme is still skeptical.

However, Boehme does not negate the value of OLED, he believes that even if the OLED is less efficient than LED, short life, but the cost is lower than LED. In addition, the biggest advantage of OLED is not in the lighting itself, but replace the LCD TV and computer screens display (LCD) technology, OLED cheaper, can be made of a flexible material, perspective and color range is wider, and more efficient than LCD.

Source: China Semiconductor Lighting Network