If you have ever tried to watch any video on a tablet on a sunny day, you know you have to tilt it at just the right angle to get rid of glare or invest in a special filter. Now it seems like this problem could be solved soon, all thanks to the new technique invented by Imperial scientists.
OLEDs (organic light emitting diodes) are largely used to lit the pixels of many modern screens for TVs, smartphones, tablets, and laptops. These OLED screens are covered with anti-glare filters to make sure the images or videos can be viewed from such screen on a bright sunny day.
However, because of the physics of how the anti-glare filter works, half of the light generated by each OLED pixel remains trapped within the display. And this reduces the energy efficiency of the OLED.
Smartphones would not be popular if their screens cannot be read outside. So, the manufacturers of these displays have chosen to sacrifice energy efficiency to increase usability.
A new type of OLED – developed by a team of Imperial scientists from the Departments of Physics and Chemistry – avoids this shortcoming. By controlling the chemistry of the OLED materials, the team shows it is possible to produce OLEDs that give off a special type of polarised light, which can bypass the anti-glare filter.
According to the team, displays made from such OLEDs should be more energy efficient, which means they will have longer battery life and lower carbon footprint.
“Our study suggests, for the first time, that by changing our OLED recipe we can generate efficient polarising OLEDs. The findings could make screens of all kinds brighter, with better contrast and longer life,” said Dr. Wade, of Imperial’s Department of Physics.
The study was mainly focused on OLEDs for displays, but the team also notes that their newly developed materials and approaches could have further applications elsewhere. The polarised light generated by their materials has potential applications in the storage, transmission, and encryption of information and so could be useful in computing and the data revolution.
Their results are detailed in the journal ACS Nano.