At COMPUTEX TAIPEI 2018, ITRI demonstrated the new Micro LED signage module which transfers Micro LED chip directly on PCB substrate. This achievement suggests that the display module has a great potential to reduce the cost and can be applied on products like video wall and indoor signage through splicing.

CLEDIS, Micro LED display introduced by SONY in 2017, applied similar technology using PCB substrate as backplane, but the Micron-size chips needed to be packaged before transferring to PCB as the substrate was not smooth enough for direct transfer. The solution introduced by ITRI in COMPUTEX 2018 has overcome the difficulty and provide possibility to produce Micro LED display module with lower cost in the future.

According to LEDinside, with the technology, the cost of the module could be reduced up to 30% comparing to fine-pitch display, thus it could change the commercial display market once the technology becomes more mature.

ITRI partners with Macroblock, Unimicron and PlayNitride to realize the production of Ultra-Fine Pitch Micro LED Signage Module by 2019

The product displayed by ITRI was developed together with Taiwanese companies, Macroblock, Unimicron and PlayNitride. Macroblck , LED driver IC Company, is responsible for passive matrix driver to drive and correct Micron-size LED chips. Then Unimicron produces the requested PCB substrate. And the semiconductor producer, PlayNitride, helps to mass produce the Micro LED chips designed by ITRI.

ITRI cooperated with the three producers and developed passive matrix driver “Ultra-Fine Pitch Micro LED Signage Module for Displays”, the size of LED chip die is between 50 µm - 80 µm, the pitch is below 800 µm, and the module size is 6 cm x 6 cm with definition 80 x 80 pixels. It could be combined and connected to fit different size video wall and indoor signage.

However, currently there are still some technical obstacles to be overcome. Ultra-Fine Pitch Micro LED Signage Module can display colors but not yet “’R’GB full color” due to the material limitation of red LED and the color is easily effected after transferred because of the roughness of conventional PCB substrate. These issues stress the complication of directly transferring Micro LED to PCB substrate and the difficulty to control the uniformity. Currently the team is working to break through the restrictions.

Macroblock will be in charge to commercialize Ultra-Fine Pitch Micro LED Signage Module and to carry out the request skills into the application of signage for the market. LEDinside speculate that by 2019, Micro LED signage will appear in our life.

Transparent Micro LED Signage Module

There is another transparent Micro LED signage module demonstrated in COMPUTEX 2018, the specification is the same as Ultra-Fine Pitch Micro LED Signage Module but the transparent signage module is based on ultra-thin glass substrate, on which RGB full color can be displayed. Also, as Micro LED takes smaller portion of the pixel area, the transparency could reach 60% and higher, plus the ultra-lightness, this transparent Micro LED signage module is suit for outdoor area and to be applied on windows, interactive screens and vending machines.

(Media source: TechNews, Angela Yang )