Research could spark ‘next generation’ screens

Researchers have developed a proof of concept technology that they believe could lead to ‘next generation’ screen displays beyond current LCDs and LEDs.

Dr Lei Xu, a team member from Nottingham Trent University
Dr Lei Xu, a team member from Nottingham Trent University

The researchers, from Nottingham Trent University, the Australian National University and the University of New South Wales Canberra in Australia, believe that their technology could enable screens and electronic devices to become thinner, offer higher resolution and be much more energy efficient.

They have engineered electrically tuneable arrays of nanoparticles called ‘metasurfaces’ which could offer significant benefits over current liquid crystal displays.

Today’s display market offers a large range of choices, but factors such as production costs, lifespan and energy consumption have kept liquid crystal technology the most popular for screens such as TV sets and monitors.

Liquid crystal cells are responsible for switching the transmitted light on and off and are lit by a backlight, with polarising filters in the front and behind the pixels. They determine the dimension of pixels – the resolution – and play a significant role in managing the device’s power consumption.

According to the team, the newly-engineered metasurface cells have ‘extraordinary’ light scattering properties. They would replace the liquid crystal layer and would not require the polarisers, which are responsible for a large amount of wasted light intensity and energy use in displays.

Researchers confirmed that the metasurfaces are 100 times thinner than liquid crystal cells and offer a tenfold greater resolution as well as consuming 50 per cent less energy.

As part of the study, they demonstrated that pixels could be electrically-programmed and the light could be switched almost 20 times faster than human aversion response time by changing the temperature of the material.

Researchers believe their technology is compatible with modern electronic displays and fills a technological gap for tuneable metasurfaces capable of switching light effectively at high frequencies.

MORE IN ELECTRONICS

“The most important metrics of flat panel displays are pixel size and resolution, weight and power consumption. We have addressed each of these with our meta-display concept,” said project leader Mohsen Rahmani, professor of engineering at Nottingham Trent University’s School of Science and Technology and a Royal Society Wolfson Fellow.

“Most importantly, our new technology can lead to a huge reduction of energy consumption – this is excellent news given the number of monitors and TV sets being used in households and businesses every single day.”

Rahmani explained that the team believes it is time for LCD and LED displays to be phased out in the same way as former cathode ray tube (CRT) TVs over the past ten to 20 years.

Dr Lei Xu, a team member from Nottingham Trent University, added that artificial intelligence and machine learning techniques could be employed to design and realise even smaller, thinner and more efficient metasurface displays.

“Our pixels are made of silicon, which offers a long life span in contrast with organic materials required for other existing alternatives,” added Professor Andrey Miroshnichenko, a team member from the University of New South Wales Canberra.

- Khosro Zangeneh Kamali, Australian National University

“Moreover, silicon is widely available, CMOS compatible with mature technology, and cheap to produce.”

The work is reported in the journal Light: Science & Applications.