A team at Kyushu University in Japan recently announced a new combination of emitter molecules that can produce an efficient emission of pure blue light that remains bright for a certain period of time, overcoming the challenge of previous OLED displays that lacked efficient blue light.
Current OLED displays face challenges with blue light sources. While there are high-performance red and green organic light-emitting diodes, there is a lack of blue light sources with similar performance.
The researchers said that while red and green OLED options are growing, there is still a lack of components capable of emitting efficient blue light.
Blu-ray components are often tradeoffs in terms of efficiency, color purity, cost and life span.
The researchers added that although Fluorescence based blue light emitters currently on the market are relatively stable and have been used in commercial displays, they have low Maximum Efficiency.
Phosphorescent Emitters, which achieve the desired 100 percent Quantum Efficiency, have a shorter life span and must use expensive metals such as Iridium or Platinum.
The team from the Center for Organic Photonics and Electronics (Opera) at Kyju University has developed a molecule based on Thermally Activated Delayed Fluorescence (TDAF), which can achieve the same luminous efficiency without the presence of metal atoms and exhibit emission capabilities for a wide range of colors.
The researchers used a bimolecular method called hyperfluorescence, in which molecules quickly convert non-luminous triplet states into singlets and transfer energy to molecules called v-dabna for pure blue emission.
The researchers point out that compared with most transmitters, v-dabna can absorb wavelengths very close to the color of its emission.
This unique property allows it to absorb most of the energy from the emission intermediaries and still emit a pure blue color, further improving color purity and longevity.
The researchers estimate that at milder intensification, the device can maintain 50 percent brightness for more than 10,000 hours;
While this is still a short time for practical applications, a tightly controlled manufacturing environment offers the opportunity to achieve a longer life.
It is hoped that this blue OLED will soon replace the existing blue light emitter to meet the demand for ultra-high resolution displays.