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During Display Week 2023, Tianma demonstrated its latest microLED display prototypes - all of which are transparent displays, stating that the main application for such displays is in the automotive sector.

The first display is a 8.75" panel, offering a resolution of 880x480 (114 PPI), a brightness of 800 nits and high transparency of over 70%. The display is an active-matrix microLED produced on an LTPS backplane.

AUO has demonstrated its latest microLED displays at Display Week 2023. Most of these displays have been shown before, but this was an impressive lineup for the Taiwanese display maker, and we'll detail the displays below.

So first up we have the 13.5" 1920x1080 (163 PPI) transparent microLEDs, which AUO says is the highest-resolution transparent microLED display ever demonstrated. The display offers a transparency of 55% and a high brightness of 5,000 nits. The microLEDs used in this display are 30 micron in size.

AR microLED microdisplay developer Mojo Vision announced that it has achieved a process milestone and has lit-up its first 300 mm GaN-on-Silicon blue microLED array wafer. The company says it is on track to maturing its 300 mm CMOS fab process.

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Mojo Vision is developing microdisplays based on blue LEDs and quantum dots color conversion. The company developed the world's highest density microLEDs, achieve up to 28,000 PPI (sub-micron LEDs).

US-based Q-Pixel announced that it has developed a 5000 PPI full-color microLED microdisplay, based on its proprietary Polychromatic microLED technology.

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Q-Pixel's technology enables a single-pixel color-tunable microLED device. The displays are produced using a monolithic process. As the company is still in stealth-mode, we do not have more information, it will be interesting to know how this technology compares to Porotech's DPT color-tunable microLED technology.

AU Optronics is demonstrating several display at Touch Taiwan 2023, including an interesting new laptop microLED display. The display is a 14.6" 2560x1440 (QHD, 202 PPI) foldable panel, that can reach a brightness of over 1,000 and a bending radius of 4 mm.

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In addition to this display AUO is showing its 17.3" transparent microLED prototype.

Hon Hai Precision Industry (Foxconn) has announced that it has developed a new microLED microdisplay, in collaboration with Ennostar and Unikorn Semiconductor (a part of Ennostar). The company is showcasing the display at Touch Taiwan 2023 - a monochrome blue 0.12" 6500 PPI 200,000 nits display.

Foxconn says that the companies have optimized the structure of the microLED chips in a join project, and developed a new thin film protection technology tat reduces surface defects, improves external quantum efficiency, and increases product reliability. Foxconn has also developed its own quantum dots based color conversion technology that enables it to convert the display to full-color (that achieved a PPI of 3,600).

MicroLED microdisplay developer Mojo Vision announced that it has raised $22.4 million in a Series A investment round, to further develop and commercialize its microLED display technology. 

Researchers from the US and Korea, led by MIT, developed full-color vertically-stacked microLEDs that achieve the highest array density (5100 PPI) and the smallest size (4 µm) reported to date.

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To end up with such high resolution and small microLED chip size, the researchers used a 2D materials based layer transfer (2DLT) technique. The resulting microLEDs, that have near-submicron thickness, are grown on 2D material-coated substrates, removed, and then stacked.

Taiwan's Industrial Technology Research Institute (ITRI), is introducing its latest microLED microdisplay technologies, and unveils its latest microdisplay prototype.

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The 0.5" display offers full-color images (using blue LEDs and quantum-dots based color conversion), high resolution (over 2,000 PPI) and high brightness (over 20,000 nits). The display offers high power efficiency - ITRI says it consumes less than half the energy of current solutions (likely compared to OLED microdisplays).

LG Display demonstrated a 12" 100 PPI (pixel pitch 40 um) full-color stretchable MicroLED display. The display can stretch up to 20% (to create a 14" display).

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LGD says that this display can be commercialized soon, as it is highly flexible, durable, and reliable. The new display is produced on a "highly resilient film-type substrate made of special silicon used in contact lenses".