New QD technology to make screens brighter

Researchers from the University of Illinois at Urbana-Champaign, have developed a new method to extract more polarised light from quantum dots (QDs) over a large-scale area.

Of late, QDs - nano-sized semiconductor particles that produce bright, sharp, colour light - have made their way into products like high-end televisions, e-readers, phones and laptops.

However, QDs are expensive to make so there is a push to improve their performance and efficiency, while lowering their fabrication costs.

The new discovery could lead to brighter and more efficient mobile phone, tablet, and computer displays, as well as enhanced LED lighting.

"Since screens consume large amounts of energy in devices like laptops, phones, and tablets, our approach could have a huge impact on energy consumption and battery life," said lead author Gloria See.

The research team, led by professor Brian Cunningham, embedded QDs in novel polymer materials that retain strong quantum efficiency.

They then used electrohydrodynamic jet (e-jet) printing technology to precisely print the QD-embedded polymers onto photonic crystal structures.

These photonic crystals limit the direction that the QD-generated light is emitted, meaning they produce polarised light, which is more intense than normal QD light output.

With polarised light, the optical efficiency is doubled, said researchers.

"If you put the photonic-crystal-enhanced quantum dot into a device like a phone or computer, then the battery will last much longer because the display would only draw half as much power as conventional displays," See explained.