The Lenovo ThinkVision M14d portable monitor ($499) has much in common with its 14-inch predecessors—the ThinkVision M14 and touch-enabled M14t—but fills a niche all its own. It skips the 16:9 widescreen aspect ratio format of most notebooks and mobile displays in favor of a slightly taller 16:10 ratio that's become increasingly popular among laptops of late. It has a higher native resolution than most portable panels, a sturdy hinged stand, and dual USB-C ports that support both data and power delivery. It's not cheap, but the M14d earns our latest Editors' Choice award among portable monitors.

The Design: Squaring Things Away

The ThinkVision M14d is nearly identical in appearance and features to the M14 and M14t; the most obvious difference is the housing that accommodates its extra vertical screen space. Although we've seen several monitors with 16:10 aspect ratios—including the Acer ConceptD CM2241W and Dell UltraSharp 30 (U3023E)—recently, the M14d is the first 16:10 portable monitor we've reviewed.

Actually, 16:10 panels were common in the early years of the century, but by 2010 most monitors had followed laptops' migration to the widescreen 16:9 format used for digital television. That aspect ratio gives notebooks a small advantage in compactness and portability, and 16:9 is ideal for movie and video viewing and editing. But 16:10 monitors are a better fit for photo editing because they're closer to the 3:2 aspect ratio of full-frame and APS-C digital SLRs and the 4:3 aspect ratio of Micro Four Thirds and many point-and-shoot digital cameras. The taller layout is also good for office productivity, as a 16:10 monitor lets you see more rows of a spreadsheet or more lines of a Word document or webpage without scrolling.

Among 16:10 monitors, while the Acer CM2241W packs 1,920-by-1,200-pixel (WUXGA) resolution and the Dell U3023 has 2,560 by 1,600 (WQXGA), the Lenovo M14d has an IPS panel with 2,240-by-1,400-pixel resolution (and no alphabet-soup acronym to go with it). The only other device I've encountered with this resolution is the Lenovo IdeaPad 5 Pro laptop.

The ThinkVision M14d is a good match in color (raven black) and design for Lenovo laptops, especially in the ThinkPad and ThinkBook lines. Counting its stand, it measures 8.5 by 12.4 by 4.2 inches (HWD) and weighs 1.3 pounds. The frame holding the panel attaches to a flat base, which extends behind the screen and supports it via two hinges. This gives the stand a sturdy feel and a full range of tilt adjustment; the top of the screen can be moved anywhere from 5 to 90 degrees away from the user. This is preferable to many portable monitors' "origami" folding stands that support only two or three specific tilt angles.

As for the monitor's ports and controls, on the left side of the base are the power button and a USB Type-C port, along with a notch for a Kensington cable lock. On the right are a second USB-C port, a button that launches the onscreen display (OSD) menu, and a rocker switch that helps navigate it. From the OSD, you can control settings such as brightness, contrast, display mode (sRGB, Neutral, Warm, or Cool), language, and aspect ratio. In testing with a 16:9 aspect ratio laptop, with the M14d set to Original AR (aspect ratio), the mirrored image of the computer screen fills the display's width with black bars above and below; the Full Screen setting vertically stretches the image to fill the panel's height. I preferred using the Original AR setting to avoid the minor distortion inherent in stretching the image.

The Lenovo's range of OSD settings are about average among recent portable monitors. The ViewSonic TD1655 and the Asus ZenScreen Touch (MB16AMT), both rival touch-enabled portable monitors, feature mini joystick controllers for navigating their OSDs. The gaming-centric Asus ROG Strix XG16AHPE has a robust OSD that includes gaming-related settings. The ThinkVision M14t's menu is largely centered on its touch features. The ThinkVision M14's controls are limited to a rocker switch to increase or decrease brightness and a button to toggle low-blue-light mode, as with the Dell 14 Portable Monitor (C1422H).

You can connect the M14d to a laptop using either the right- or left-side USB-C port, depending on which side of the laptop you want to put the display. You can even connect to an Android smartphone if it has a USB-C port. The ports support both DisplayPort over USB Alternate Mode and USB power delivery, letting you power or charge a laptop connected to the monitor with the latter plugged into a wall outlet.

The M14d comes with a soft, charcoal-gray carrying sleeve that provides a measure of protection when the display is being transported in a bag or backpack.

Testing the Lenovo M14d: Bright, Strong Contrast, Good Color

As usual, I did our color and brightness testing using a Klein K10-A colorimeter and Portrait Displays' CalMAN 5 software. Lenovo rates the ThinkVision M14d's luminance at 300 nits (candelas per square meter); it came up just short of that at 287 nits in my testing. This is in the upper tier of brightness for portable monitors; the Asus Strix comes close at 272 nits, while the ThinkVision M14 delivers 280.

The monitor's advertised contrast ratio is 1,500:1; I measured it at 1,231:1, which is obviously less but still among the best we've seen from a mobile display. Most competitors have contrast ratios somewhere between 700:1 and 1,000:1.

The M14d has good color gamut coverage for a portable monitor, covering 96.3% of the sRGB space in my testing (see the chromaticity chart above). That's slightly lower than the Asus Strix's 97.7% or the 97% and 97.9% of the Lenovo M14 and M14t respectively, but considerably better than the ViewSonic TD1655's measly 61.1% sRGB coverage.

In addition to our formal testing, I viewed a selection of film clips and photos using both a 16:9-aspect-ratio Lenovo ThinkPad T490 (using the monitor's Original AR setting) and a 16:10 HP Pavilion Aero 13. In both cases, videos were bright, with well-saturated colors, and showing very good contrast in both light and dark areas. Photos also looked bright, with natural-looking colors and excellent contrast.

An Excellent, if Costly, Mobile Monitor

If you own one of the many laptops now on the market with a 16:10 aspect ratio, and you want to pair it with a portable monitor, you can't do better than the Lenovo ThinkVision M14d. It will match your notebook's screen, letting you take full advantage of the extra vertical space that the taller ratio brings. Of course, you can use the display with a 16:9 laptop as well, though you'll either get a little blank space above and below the image or a slightly mismatched (or possibly stretched) view.

The display includes the features we've applauded in other ThinkVision M14 models—a sturdy stand with a wide tilt range, dual USB-C ports that let you position the monitor on either side of the laptop, and support for USB power delivery as well as DisplayPort over USB. Its screen is bright, with good contrast and color coverage, and it has the handy onscreen display the original M14 lacks.

The M14d's only real sticking point may be its price, which puts it alongside the ThinkVision M14t, the Asus XG16AHPE, and the 15-inch espresso Display in the realm of premium portable monitors. Still, it's money well spent, especially if you have a 16:10 laptop. The ThinkVision M14d is our latest Editors' Choice winner.