Stacking red, green and blue MicroLED emitters directly above one another can free pixel area otherwise taken up by side-by-side subpixels. In a 2023 laboratory demonstration, researchers reported a vertically stacked array with 4-micrometre pixels at 5,100 pixels per inch (PPI). Those are research results, not specifications for a retail display or headset; the approach is a possible route to denser microdisplays for applications such as AR and VR.
What vertical RGB stacking changes
A conventional RGB pixel places its red, green and blue emitters beside one another. As pixels shrink, those neighboring emitters take up a larger share of each pixel’s lateral area, constraining how closely pixels can be packed. A vertical stack places the colour emitters in the same footprint, addressing that space constraint.
The 2023 team described each stacked pixel as capable of generating the full commercial range of colours. That is a capability reported by the study, not certification against a particular display standard.
How the 2023 MicroLED stack was made
- Grow thin LED layers: The researchers grew near-submicrometre-thick red, green and blue LED layers on substrates coated with two-dimensional materials.
- Release the layers: Using remote, or van der Waals, epitaxy, they mechanically released the LED membranes from their growth substrates.
- Stack and fabricate: They stacked the membranes and fabricated the device from the top down. The paper also demonstrated vertical integration of blue MicroLEDs with silicon membrane transistors for active-matrix operation.
This is the process reported by the authors; it should not be taken as a description of how all MicroLED displays are made.
The Tool Desk
Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
What the reported pixel figures mean
| Reported measurement | What it describes |
|---|---|
| 5,100 pixels per inch | The array density reported for the 2023 vertically stacked MicroLED demonstration. |
| 4 micrometres | The reported pixel size in the 2023 demonstration. |
| Around 9 micrometres | The reported stack height; the 2023 authors identified the thin stack as important to achieving the array density. |
These measurements describe a research array. They do not establish that a consumer display or headset has the same density or pixel size, or that the process is commercially ready. The cited reports do not establish product-level cost, manufacturing yield, lifetime or power consumption.
How this differs from an earlier vertical-stacking study
Vertical stacking was not new in 2023. A 2019 study by Geum and colleagues described a separate method: bonding-interface-engineered monolithic integration, using SiO2/SiNx distributed Bragg reflectors as both a bonding layer and colour filter. It reported an optically pumped array with a 0.4-micrometre pitch, corresponding to 63,500 PPI. That figure belongs to the 2019 demonstration, not the 2023 transferred-membrane array; the distinct methods and demonstrations should not be treated as a like-for-like comparison.
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
Why AR and VR are a possible application
High pixel density is relevant to small displays used close to the eye, making compact AR and VR microdisplays a potential application for stacked MicroLEDs. In MIT News’ 2023 report, associate professor Jeehwan Kim called the result “the smallest micro-LED pixel, and the highest pixel density reported in the journals.” That is Kim’s claim as attributed in the report, not a statement that a product with those specifications is on sale.
MIT News also quoted postdoctoral researcher Jiho Shin saying, “For virtual reality, right now there is a limit to how real they can look.” The proposed immersive benefit remains prospective: the study reported a fabrication demonstration, not a shipping VR display. A separate January 2026 KAIST news item discusses work on red MicroLED efficiency and resolution, illustrating that colour-specific performance remains an active research area; it does not show that the 2023 stacked process became a commercial product.
Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
Are vertically stacked MicroLED displays available?
The cited studies and institutional reports establish research demonstrations, not the availability of a named commercial screen or headset made with the 2023 process. They also do not provide a controlled comparison against retail displays. Treat the reported density and pixel dimensions as evidence of what the laboratory array achieved—not as a buying specification or proof of performance, price, or readiness in a consumer device.
Quick Recap
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
Sources
- Nature, “Vertical full-colour micro-LEDs via 2D materials-based layer transfer” (2023)
- MIT News, “Engineers invent vertical, full-color microscopic LEDs” (2023)
- Georgia Tech News Center, “Researchers Pioneer Process to Stack Micro-LEDs” (2023)
- Nanoscale / KAIST record, “Strategy toward the fabrication of ultrahigh-resolution micro-LED displays by bonding-interface-engineered vertical stacking and surface passivation” (2019)
- KAIST News Center, “KAIST Solves Key Micro-LED Challenges, Enabling Reality Like Visuals for AR/VR Devices” (January 2026)
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
