A research team from the UK's Nottingham Trent University, the Australian National University and the University of New South Wales Canberra has developed a proof-of-concept display technology that could replace the LCD panels common to many of today's big-screen TVs.
Though some modern high-end televisions may sport quantum-dot displays or OLED panels, many of the cheaper models available will use LCD (liquid crystal display) technology, polarizing filters and LED backlighting. But the researchers say that the limit has been reached for development of this kind of technology.
"The capability of conventional displays has reached its peak and is unlikely to significantly improve in the future due to multiple limitations," said Dragomir Neshev, Professor in Physics at the Australian National University. "Today there is a quest for fully solid-state flat display technology with a high resolution and fast refresh rate. We have designed and developed metasurface pixels that can be ideal for the next-generation display. Unlike liquid crystals, our pixels do not require polarized lights for functioning, which will halve screens’ energy consumption."
To control individual pixels at a high modulation rate, the proof-of-concept platform employs transparent conductive oxide to serve as an electrically driven heater that can quickly change the optical properties of the silicon metasurface cells, which are said to be 100 times thinner than liquid crystal cells or 200 times thinner than a human hair. The technology results in response times of under a millisecond – reported as 10 times faster than the detection limit of the human eye.
"Our pixels are made of silicon, which offers a long life span in contrast with organic materials required for other existing alternatives," noted Professor Andrey Miroshnichenko of the University of New South Wales Canberra. "Moreover, silicon is widely available, CMOS compatible with mature technology, and cheap to produce."
This technology could also be used for dynamic VR holography, in LiDAR technologies, and make for the production of thinner flat panels at 100x higher resolution than current LCD-based screens, while cutting power consumption by half.
Additionally, since the metasurface array could effectively just replace the liquid crystal layer in today's displays, the researchers reckon that manufacturers won't need to invest in brand new production lines to make panels.
The project will now look at scaling up the technology for big screen TVs, as well as further improving the performance of the metasurfaces using AI and machine learning.
"We have paved the way to break a technology barrier by replacing the liquid crystal layer in current displays with a metasurface, enabling us to make affordable flat screens liquid crystal-free," said lead researcher Mohsen Rahmani, Professor of Engineering at Nottingham Trent University’s School of Science and Technology. "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.
"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. We believe 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 10 to 20 years."
A paper on the research has been published in the journal Light: Science & Applications.
Sources: Nottingham Trent University, Australian National University, University of New South Wales Canberra