30 Aug Display Week unveils innovations in microLEDs and foldable screens
Display Week, the industry’s annual conference in Los Angeles, which took place at the end of May this year, focused on two transformational technologies – microLED screens and foldable displays.
Celebrating its 60th anniversary this year, this is a key event for the display industry where technologists rub shoulders with designers, academics mingle with marketers and device manufacturers such as Apple and Samsung look out for the latest innovations.
Attendees are united by a passion for displays and most have a PhD in a relevant area. While it may not be an ideal location for non-experts or display industry novices, when a new technology makes a splash at Display Week, it is well on its way to becoming the next big thing. So we can expect that by the end of this decade, microLED displays will be everywhere and many of our screens will be foldable – and may even have more than one fold.
Smartkem was out in force at this year’s event, with our chief marketing officer Sri Peruvemba briefing journalists on the proceedings and handing out awards. Our chief executive Ian Jenks delivered the keynote address “The next generation of microLED displays” for the business conference. Ian’s speech made the case for the industry to adopt Smartkem’s TRUFLEX® semiconductor inks in the manufacture of microLED displays.
Billed as the screen technology of the future, microLED displays promise superior quality to current displays such as LCD and OLED. Offering exceptional brightness and clear contrasts between black and lighter shades, they also have a wide colour gamut, low energy use and can be viewed clearly from every angle.
MicroLEDs are emissive – like OLEDs, the microLEDs emit their own light source so do not need the panel of backlights essential for lighting up liquid crystal displays. This means the displays can be much thinner than LCDs.
Adding to the excitement over the nascent technology, this year could be a turning point for microLED displays with rumours of a new smartwatch launch within the next few months using a microLED screen. The low power consumption of microLED displays makes them ideal for portable devices such as watches and AR/VR devices which cannot accommodate large batteries.
But the technology must overcome some significant hurdles before it achieves mass production. The displays consist of millions of tiny LEDs – each the breadth of a human hair – which are grown on a silicon wafer. They are then transferred on to a glass substrate from which the display is cut. This “mother glass” could be up to 10 ft square and is then cut into screens for the relevant device, whether TVs, mobiles or tablets. One sheet could probably create 1,000 watch screens.
Each LED transferred on to the mother glass must sit on top of a transistor, which controls its light emissions to create the overall picture. The microLEDs and transistors are welded together through a high temperature process. This is a highly complex and difficult operation with huge scope for error – transferring and welding millions of tiny LEDs and transistors needs constant correction. The difficulty of standardising this process is currently holding back the commercialisation of microLEDs.
This is where Smartkem’s solution could transform the fortunes of microLED displays, as Ian Jenks showed in his keynote address. Through Smartkem’s lower temperature process using semiconductor inks, organic thin film transistors can be laid directly on top of the microLEDs, eliminating the need for mass transfer and laser welding. This process can be carried out using low-cost manufacturing tools currently used for LCD backplane manufacturing.
This revolutionary process is lower cost and, importantly, is carried out at 80 degrees centigrade rather than the 300 to 400 degrees of existing processes. The lower temperature means the process can be used on plastics and light substrates which would melt at the higher temperatures. These flexible substrates are ideal for lightweight displays that can be cut into a variety of shapes.
Smartkem’s process opens the way for the commercialisation of microLED displays and offers the industry a way forward with the new technology.
But this is already a crowded market. LCD displays account for 70% of the $150 billion display market, with OLED taking up most of the rest. The manufacturers of LCD and OLED displays are likely to put up considerable resistance to the spread of micro-LED displays.
It could take some time for manufacturers to switch to microLEDs, though once they see the superior image quality on offer, they are likely to seek competitive advantage by commercialising them.
Another theme of this year’s Display Week is the growing use of foldable screens. Foldable phones are already commonplace, and the industry is now looking to create foldable laptops and tablets.
Most foldable screens are made using OLED screens. This is another area where Smartkem’s technology can offer a low cost and low temperature solution. TRUFLEX® inks lend themselves very well to these flexible substrates. The low temperature process means the displays can use plastic substrates.
Foldable screens are an important development in unlocking screen space and allowing for ever larger screen viewing. A laptop folds across a hinge and one half contains the keyboard while the other half contains the screen. A screen that can cover the whole of this area effectively doubles the screen space. The keyboard could be called up on the screen as occurs with a smart phone, then once a video plays, the keyboard disappears allowing the screen to cover the entire area.
Once again, Display Week has offered a glimpse into the future of screen technology.