Plessey Semiconductors and Nanoco Technologies have announced a partnership to shrink the pixel size of monolithic microLED displays using Nanoco’s cadmium free quantum dot (CFQD quantum dots) semiconductor nanoparticle technology.
Plessey is a UK-based developer of advanced optoelectronic technologies and Nanoco harnesses the power of advanced nano-materials by producing innovative quantum dots.
Using its existing monolithic process, Plessey will integrate the Nanoco CFQD quantum dots into selected regions of blue LED wafers to add red and green light. This shrinks the smallest practical pixel size from today’s 30µm (micrometre) to just 4µm, a reduction of 87%. The process will enable the production of smaller, higher-resolution, microLED displays in applications such as AR/VR devices, watches, and mobile devices, while enhancing both colour rendition and energy efficiency.
For pixels of 30µm or greater, colour conversion is currently performed by adding phosphors to the blue die. However, since the smallest phosphor particle is around 30µm, the efficiency of colour conversion deteriorates as the pixel size shrinks. Nanoco’s CFQD quantum dot technology overcomes this limitation while facilitating efficient, compact device packaging.
“Quantum dots offer the best solution for today’s emerging display requirements,” said Mike Lee, president of corporate and business development at Plessey. “The nano-sized emitters with narrow band emission make them a suitable solution for Plessey’s microLED display roadmap, which will see pixels being driven down to 4µm in size by 2019.”
Dr. Brian Gally, Nanoco’s head of product commented: “We are thrilled to be working in close collaboration with Plessey, who lead the global field in the development and production of mircroLED arrays. The combination of Plessey’s blue microLEDs with Nanoco’s red and green cadmium free quantum dots gives display customers the performance they require to rapidly commercialise products.”
MicroLEDs are considered by many to be brighter, smaller, lighter, more energy-efficient compared to other display technologies and have a longer operating life. Where they replace OLEDs, for example in AR/VR goggles or head-up displays, Plessey microLEDs are said to offer 10 times the resolution, 100 times the contrast ratio, and up to 1,000 times the luminance. They do so at half the power consumption, doubling battery life in portable devices. They also feature perfect blacks, realistic colour, and immunity to burn-in or decay over time.