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AUO had an impressive booth at Displayweek, showing some of its latest microLED prototypes. It is clear that the company is highly focused on microLED technology as its next-gen display strategy.

First up, with a 31" large area single-panel microLED, which AUO says is the world's largest. The display is produced on a single glass LTPS backplane, and offers 120Hz and a brightness of 500 nits. AUO calls this a Large Size A.R.T. MicroLED display.

Towards the end of 2020, Samsung announced it's first "consumer" 110-inch 4K MicroLED TV, and then in early 2021 it said it will release smaller microLED TVs, including 77" and 88" models.

According to a new report from Korea, Samsung Electronics canceled its plans to release these smaller microLED TVs, as the company could not reduce prices enough and the asking price for a 77" microLED would not be attractive to customers.

According to a new report from Korea, Samsung plans to build a new TV production line in Vietnam, that will be dedicate to microLED TV production. The new plant will begin production in 2022, and will be used to produce its upcoming smaller 77-inch and 88-inch TVs. Samsung is also expanding its facility in Vietnam which is currently used to produce the 110-inch microLED TVs.

Samsung aims to reduce the production costs of its MicroLED TVs, and has launched a project that will develop a TFT backplane for its future TVs (to replace the currently used PCBs). The company hopes that this will enable it to reduce the production costs of its microLED TVs to the level of its 8K QLEDs. This sounds a bit optimistic, at least for TVs in sizes such as 77-inch or 88-inch.

Last week we reported that Ennostar Incorporation (formed by a merger of Taiwan's Epistar and Lextar in 2020) demonstrated a 10.6" transparent microLED display at Touch Taiwan 2021. We now have more information on Lextar's new display prototype.

Global digital signage solution provider STRATACACHE is constructing the first US-based complete display production facility in Eugene, Oregon. The future MicroLED E4 fab is planned to commence production in 2022, and the fab will be a complete microLED production line, from epiwafer (on 300 mm silicon wafers), through transfer process and to final module assembly.

This project is extremely interesting, and we set out to discuss it with STRATACACHE's founder and CEO, Chris Riegel. At STRATACACHE, Chris leads strategic direction, technology development and engineering operations, and the MicroLED fab project seems to be personally spearheaded by him.

In June 2019 Micro-LED developer Glo announced a partnership with Japan-based display maker Kyocera to demonstrate a 1.8" Micro-LED display. Here's Kyocera's booth at CEATEC 2019 that features this display (03:00):

The Glo microLED display features a resolution of 256x256 (200 PPI), a peak luminance of 3,000 nits and a color gamut of 81% Rec.2020. The display's frame rate is 240Hz and the response time is 7 usec or less. For this demonstration panel, Kyocera provided the LTPS backplane and driving technology while glo provided its InGaN RGB micro-LEDs and its transfer technology.

US-based Lumiode has been developing MicroLED Microdisplays for many years, but the company has been very quiet and did not disclose much about its technology. We have recently met with Vikas Dhurka (VP Marketing) and Eddy Hsu (director of Display Systems) who explained and demonstrated the company's technology.

Lumiode has developed a unique technology for the fabrication of TFT backplanes directly on top of Micro-LED arrays. This enables an entirely monolithic process (with no wafer bonding) to create highly bright and efficient microdisplays.

AU Optronics announced that it will demonstrate a 12.1" LTPS micro-LED display prototype next week that features a resolution of 1920x720 (169 PPI). It seems that this is the same display shown at IFA 2018.

The 2018 display used blue LEDs with color conversion, which achieved "marvelous color performance", according to AUO.

Researchers from the University of Waterloo have demonstrated the successful integration of a-Si:H TFTs and high-efficiency micro-LED chips on large-area flexible substrates. This is the first time that an amorphous silicon was used to drive Micro-LEDs which could pave the way for lower-cost micro-LED display fabrication using existing LCD technology.

the researchers use a 2-TFT pixel circuit, with blue GaN-based micro-LED chips. The low-temperature TFT production process enabled the direct integration onto a flexible flexible polyethylene naphthalate (PEN) substrate. After the TFT fabrication, the micro-LED chips were flip-chip bonded on the TFT, and then transferred onto the flexible pixel circuit using a selective laser lift-off process.

TCL subsidiary China Star (CSoT) demonstrated a 3.3" 232x116 transparent Micro-LED prototype display. The display is built on an Oxide-TFT (IGZO) backplane - CSoT says that this is the first such display ever demonstrated. The transparency is around 45%.

CSoT says that it developed the display in collaboration with PlayNitride that provided the transfer technology for CSoT.