Sebastian Reineke, professor of organic semiconductors at Dresden University of Technology in Germany, said: 'The screen will be more energy-efficient and its service life will be extended.' The technology was invented by the cooperation between Dresden University of Technology and the Autonomous University of Barcelona.
Several years ago, smart phones introduced OLED screens, and Apple iPhone X installed OLED screens. Compared to LCDs, OLED screens are thinner, lighter, and brighter. However, OLEDs also have shortcomings and their life span is shorter. What about improving OLED screens? They didn't use new organic polymer materials to make screens, they didn't redesign the screen structure, they simply changed the OLED manufacturing process.
It turns out that when the raw material is deposited on the substrate, it only needs to raise the temperature to improve the OLED screen. When the temperature reaches a certain condition, the material changes from a glassy state to a rubbery state. For many organic materials, this temperature is about 100. Celsius. The researchers heated the polymer to a temperature of 80-90% of the conversion temperature to produce 'ultra-stable glass'.
In general, OLEDs use polymers that are loosely bound and not perfectly aligned, and may react with each other. If it is 'superstable glass', the molecular arrangement is more perfect and it is in the lowest energy state, so it will be more stable. .
If there is a defect, the lifetime of the OLED screen will be shortened, and the probability that the ultra-stable glass will be defective will be much lower. Moreover, the vibration amplitude of this glass will be much smaller, so the OLED screen will generate fewer photons, and these photons will be fused with the charge carriers. , adversely affecting the screen; not only that, in the new screen, excess energy is dissipated as heat rather than light.
The researchers used four kinds of commonly used phosphor emitters to test and found that the life span was increased by 15% and the energy saving rate was 15%. If installed on a mobile phone, how long can the battery life be extended? There are many factors that determine the battery life, and different usage methods will also affect Life time. Reineke said: 'For each product, life is an important consideration, such as display, solid-state lighting device, if you can extend the service life, the market will accept.'
Next, the researchers will use more OLED materials to test new technologies. Then it depends on whether or not heating technology can be used in the manufacturing process, and it can not increase too much cost. Reineke and German OLED manufacturer Cynora are testing new technologies.