What They Say
LEDInside.com (Trendforce) has reported on Opto Taiwan, the only international optical and optoelectronic exhibition in Taiwan this year. MiniLED and microLED took centre stage, it said.
Innolux showed a 24.6″ microLED display with 960 x 360 resolution, and was made from four sub-modules. The LEDs used QDs for colour conversion. The company also showed a 55″ based on 32 9″ modules with 1.2mm pitch LEDs giving an overall 960 x 540 resolution. This was a CoB architecture with a PCB backplane.
A display for the desktop was shown by the firm that had a 31.5″ diagonal and 2,000 miniLEDs in the backlight and is reported to have FullHD backlight modulation using dual cells. It is said to support 144Hz and UltraHD resolution. A 120″ 8k TV featured 14,400 Mini LED chips and 4,800 local dimming zones.
PlayNitride has been a leader in development of microLED in Taiwan and showed a 0.39″ diagonal microLED display using PCBs for AR applications. Dot density is 3,000ppi and brightness is 30,000cd/m². A second demo for larger displays, called PixeLED used PCB modules. Each PCB has 48 microLEDs (RGB) to give 16 pixels.
AeroTrans, a newcomer, talked about its mass transfer solution for microLED using lasers and laser-curable adhesive. However, it is reported to only for chips from 50 µm and above.
Lasersel of Korea has a system of IR lasers that can heat-up LED chips to allow die bonding.
At the co-located Laser & Photonics Taiwan 2020 event, Coherent showed its excimer laser used for LLO of the GaN layer from sapphire wafers with only one exposure, minimising damage.
What We Think
By our calculations, the 24.6″ display has a pitch around 0.6mm and has a 24:9 aspect, so not quite what we would call a microLED display. (BR)
