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Quantum Dots developer Nanosys announced that it acquired 3D Nanowire microLED display developer Glo. The financial details were not disclosed.

Glo has been developing GaN microLED displays on both LTPS and CMOS (microdisplay) backplane. The company, founded in 2003, has invested (according to Nanosys) over $200 million in its technology - which includes epitaxial LED growth, transfer technology and chip processing.

MicroLED developer PlayNitride introduced interesting new display prototypes at SID Displayweek 2021.

The first display is a 89-inch 5K (59 PPI) curved display, produced from tiled microLED panels. The display has a 32:9 aspect ratio with the microLEDs driven by PCB. The 89-inch display is build from 168 tiles, and it achieves a brightness of over 2,000 nits.

Tianma demonstrated several new microLED display prototypes at SID Displayweek 2021. First up is a 7.56" 720x480 (114 PPI) flexible MicroLED display, developed in collaboration with PlayNitride. The display is driven by an LTPS backplane and achieves a brightness of over 600 nits. The bending radius is 50 mm.

The second display is a tiled display that combines two 5.04" 480x320 (114 PPI) LTPS microLED displays. This one was develop again in collaboration with PlayNitride. The border (bezel) of the panel is less than 0.03 mm - although looking carefully at the display you can see a black line separating the two panels.

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.

AUO Optronics will demonstrate several new MicroLED display prototypes at Touch Taiwan 2021. AUO now brands its microLED displays as ALED displays.

The first display, which you see above, is a 1.39-inch 472x472 (338 PPI) full-circle microLED display. AUO says that this is the highest-density MicroLED display ever developed. AUO did not disclose more about this display (which was developed together with PlayNitride) but the company says that it offers ultra-wide viewing angles and high brightness.

PlayNitride introduced several new display technologies at SID DisplayWeek 2020. First up we have the PixeLED Matrix, which is a tiled microLED display module based display, each produced on its own PCB.

Each PixeLED module is made from 16 pixels (4X4), and can reach pitches of 0.3-0.4 mm. PlayNitride says that this technology can compete with mini LED displays, and says that it achieves a superior contrast and can also be fitted on curved surfaces. PixeLED displays can be used for TV displays, for commercial signage displays and also for automotive lighting. The display can currently achieve a maximum brightness of 2,000 nits.

AU Optronics and PlayNitride announced that the two companies have developed a 9.4" 228 PPI flexible microLED display. The new display is driven by an LTPS backplane and the two companies say it delivers a large color gamut, is weather resistance and it is suitable for automotive applications.

AUO and PlayNitride has been collaborating on microLED display technologies for many years. In early 2019, AUO announce it plans to accelerate its development of Micro-LED products. The company previous prototype was a 12.1" 1920x720 (169 PPI) panel. In September 2019 AUO's president said that he expects Micro-LED displays to enter the market within 1-2 years, starting with large-area signage and small-sized VR displays.

Canada-based VueReal is a startup company that develop Micro-LED based microdisplays. The company's Continuous Pixelation micro-printing technology offers high density displays, high production yields and a simple design.

VueReal's founder and CEO, Reza Chaji, was kind enough to answer a few questions we had on the company's technology and business.

Reza, thank you for your time. Can you explain VueReal's micro-printing process and technology?

VueReal’s solution is a true printing process where you do not need to pick LEDs for each transfer. It is based on a cartridge design by VueReal that releases the LEDs selectively into the substrate.

Shanghai-based Micro-LED microdisplay developer JBD unveiled two new Micro-LED microdisplay prototypes. First up is the JBD5UM720P-G, a 0.31" 720p (1780x720, 5,000 PPI) display that features a typical brightness of 3 million nits (!). This is a monochrome green (530 nm) display.

The second display, the JBD25UMFHD-B is a higher density display, at 10,000 PPI it achieves a 2560x1440 resolution in the same 0.31" size. This is a monochrome blue (455 nm) display that has a brightness of 150,000 nits. The display's refresh rate is 360Hz.

Researchers from the Korea Advanced Institute of Science and Technology (KAIST) developed a new process that enables the fabrication of highly dense MicroLED displays - up to 63,500 PPI (!).

The technique involves stacking RGB LEDs in three dimensions and a semiconductor patterning process. Stacking LEDs one on top of the other creates color interference issues, and to overcome this the researchers deposited an insulating film between the layers. This also improved the efficiency of the microLED devices.