Under-display cameras, once regarded as the ultimate solution for full-screen displays, have recently made new headlines.

Following the official debut of Apple's first foldable phone, the iPhone Duo, under-display cameras — a technology that had lain dormant for years — have once again been thrust into the public eye. At nearly the same time, RedMagic also announced the upcoming launch of its 9th-generation under-display camera technology, reaffirming its commitment to a true full-screen design for its new flagship devices.

(Image source: Apple Official)

It is worth noting that under-display cameras entered mass production as early as six years ago, and many manufacturers at the time saw them as the final form of full-screen displays. Yet years later, most phone makers that were once keen on exploring true full-screen solutions have reverted to the traditional punch-hole design. Only gaming phone brands like RedMagic have stuck with the technology to this day.

Now that Apple is also experimenting with under-display cameras, this once-overlooked technology seems to be gaining new momentum. But what Xiao Lei wonders is: what intractable problems have led so many manufacturers to abandon the technology one after another? And will it ever become a mainstream market offering again?

Why Have Under-Display Cameras Never Caught On?

In 2020, ZTE launched the Axon 20 5G, the world's first mass-produced phone with an under-display camera. Later, brands including Xiaomi and OPPO also showcased related technologies one after another. Back then, many believed that as screen manufacturing processes matured, notches, waterdrop cutouts and punch-hole designs on the front of phones would soon be a thing of the past. But six years on, the reality has turned out quite differently. Far from breaking out of the niche market, under-display cameras remain adopted by only a handful of brands such as RedMagic.

The root cause is that under-display cameras have yet to meet users' daily needs.

A standard punch-hole display leaves an opening at the camera's position, allowing light to reach the sensor directly. An under-display camera, by contrast, requires light to pass through the pixels, electrodes and other structures of an OLED screen. For all the screen's thinness, the amount of light that can actually penetrate these layers and reach the camera is quite limited. When light intake is insufficient, the camera has to boost its sensitivity or extend exposure time, resulting in photos with heavy noise and poor image quality. The gap between under-display cameras and traditional front cameras becomes even more pronounced in low-light environments such as indoors or at night.

(Image source: Xiaomi Official)

Furthermore, the regularly arranged pixels and circuits inside the screen can also interfere with light. For example, when taking a photo of a street lamp at night with the front camera, a regular phone may only produce slight glare, while a phone with an under-display camera may capture noticeable halos that even degrade the overall clarity of the image.

To tackle these issues, manufacturers have had to adjust the screen structure above the camera — for instance, by reducing obstructions and rearranging pixels to allow more light to reach the sensor. But this brings new problems: once the pixel structure above the camera is altered, the display quality in that area may differ from the rest of the screen. Some early under-display camera phones suffered from obvious graininess, color deviation, and even a visible circular patch over the camera.

(Image source: Apple Official)

This ends up being counterproductive. Users want under-display cameras simply for a seamless front surface, yet hiding the camera ends up making the whole screen look odd. Even today, this problem has not been fully resolved. Even on the newly released iPhone Duo, the camera area is still clearly visible under certain viewing angles and display backgrounds.

At the end of the day, manufacturers always have to strike a balance between light transmittance and display quality. To make the camera capture clearer images, transmittance must be improved; to make the screen look more detailed and uniform, sufficient pixel density and an intact display structure are required. Excelling at both is no easy feat.

Of course, under-display camera technology has not stood still. Over the past few years, RedMagic has been optimizing pixel arrangement, display uniformity and front-facing imaging algorithms. Today, under normal usage, the under-display camera area is barely perceptible, and the overall screen experience is much better than that of early products. In the words of a Lei Technology review: "In indoor and outdoor daytime environments, I can't tell where the front camera is no matter what angle I look from. It's only in completely dark environments that you can barely make out its presence."

(Image source: LeiTech)

However, improved display quality does not mean the imaging problems are solved. The image quality captured by under-display cameras is still susceptible to the screen structure. Manufacturers can only rely on algorithms for noise reduction, sharpening, color restoration and diffraction correction to bring photos up to a usable standard.

But algorithms have their limits, especially in complex scenarios such as backlighting and night scenes, where lost details in the original image can hardly be fully restored. What's more, users now have increasingly high demands for smartphone selfies. Beyond basic photography, front cameras also need to handle video calls, portrait shots, HDR and high-definition video recording. It will clearly take some time for under-display cameras to match the performance of traditional solutions in these scenarios.

There is also another unavoidable issue for under-display cameras: cost. To balance light transmittance and display quality, they usually require redesigns of the screen structure, camera module and imaging algorithms, which naturally drives up R&D and manufacturing costs. In contrast, today's punch-hole displays are highly mature, with ever-smaller cutouts and solid front-camera performance. Users' obsession with full-screen displays has also cooled compared to a few years ago, and most would not reject a phone simply because of a tiny hole on the screen.

(Image source: LeiTech)

Ultimately, the biggest dilemma for under-display cameras is that manufacturers spend heavily on them, yet users may not perceive much of an upgrade. Since traditional punch-hole displays are already good enough, there is little incentive for makers to keep investing in under-display camera technology.

RedMagic Targets Gaming, Apple Aims to Elevate Foldable Screen Experience

If under-display cameras have so many flaws, why are Apple and RedMagic still willing to keep investing in them?

Starting with RedMagic: as one of the few brands still committed to the gaming phone segment, it has always prioritized screen integrity. For average users, a tiny hole on the screen may not affect daily use, but for gamers who frequently hold their phones horizontally, the camera cutout does somewhat compromise the viewing experience.

(Image source: Red Magic Official)

This is especially true in games that require frequent attention to information at the edges of the screen — an unobstructed display truly delivers a more immersive visual experience. While most games today have been optimized for punch-hole screens, given the choice, most gamers would still prefer a display without any cutouts.

Moreover, RedMagic is a distinctive brand that has always been willing to make bold attempts for the sake of gaming experience. Active cooling fans, touch-sensitive shoulder triggers and gaming-specific systems — features rarely seen on regular flagship phones — are precisely what draw core gamers to RedMagic. The same goes for under-display cameras. After all, gamers generally have lower demands for front cameras; many are willing to accept slightly worse selfie quality in exchange for a more complete gaming display. The fact that RedMagic has iterated its under-display camera technology to the 9th generation is largely because its target audience genuinely values the full-screen design.

Apple's choice to adopt under-display cameras, meanwhile, comes with an advantage RedMagic does not have: foldable form factors.

Instead of rushing to put under-display cameras on standard iPhones, Apple chose to debut the technology on the inner display of the iPhone Duo. Xiao Lei believes this approach makes sense. After all, the biggest selling point of foldable phones is the large screen when unfolded, which delivers a wider field of view than regular phones for watching videos, playing games or working on documents.

(Image source: Apple Official)

Having a prominent camera cutout on such a large screen would detract from the aesthetic. For a company like Apple that places great emphasis on product appearance and design consistency, under-display cameras hold genuine appeal.

Foldables also have an advantage over regular slab phones: they can use a combination of inner and outer displays and cameras to circumvent the biggest shortcomings of under-display cameras. The iPhone Duo retains a traditional front camera on its outer screen and uses a hidden camera on the inner display. Users can take selfies with the outer camera as usual, and switch to the inner camera for video calls when the phone is unfolded.

(Image source: Apple Official)

Additionally, foldables allow users to take selfies using the rear cameras with the outer screen as a viewfinder, delivering even better image quality than regular front cameras. This trade-off — achieving a more seamless inner screen without significantly compromising the selfie experience — is clearly much more sensible.

Interestingly, to make the under-display camera work, Apple has apparently broken with its long-standing tradition by ditching Face ID in favor of a side-mounted fingerprint sensor. After all, Face ID requires additional depth-sensing components, and hiding the entire module under the screen is far more difficult than concealing just a front camera. Side-mounted Touch ID, by comparison, is much simpler: it works whether the phone is folded or unfolded, and there is no risk of the screen form factor affecting the unlocking experience.

Of course, the loss of Face ID is regrettable. For iPhone users who have grown accustomed to face unlock, switching back to fingerprint recognition will take some getting used to. But if it means a more seamless foldable display, it is an understandable trade-off — at least for this particular product.

So while both Apple and RedMagic have opted for under-display cameras, their priorities differ. RedMagic aims to enhance gaming experience through a seamless screen while reinforcing its product identity; Apple seeks to further leverage the large-screen advantage of foldables. For both, the benefits of under-display cameras are significant enough to make the current drawbacks acceptable.

Will Under-Display Cameras Ever Go Mainstream?

Looking back at the development of the smartphone industry over the past few years, manufacturers have tried many approaches to achieve a true full-screen experience — from pop-up cameras and slider designs to today's under-display cameras. Yet most of these once eye-catching designs never went mainstream, while the seemingly unremarkable punch-hole display has endured to this day.

The smartphone market has also changed considerably in recent years. In earlier years, manufacturers could attract consumers by increasing screen-to-body ratios or changing device form factors, but today people are noticeably less sensitive to cosmetic innovations. Users may care more about camera quality, battery life and price than whether there is a tiny hole on the screen. While under-display cameras do make phones look sleeker, that alone is unlikely to be reason enough for most people to upgrade.

Still, Xiao Lei believes Apple's entry is meaningful. In the past, under-display cameras were mostly found on niche products like gaming phones. Now, as the foldable phone market gradually matures, the technology has a chance to find more applications. If the iPhone Duo performs well in the market, more manufacturers may reconsider the value of under-display cameras.

Of course, Apple's adoption of the technology does not mean other manufacturers have to follow suit. In Xiao Lei's view at least, under-display cameras will likely coexist with punch-hole displays for a long time to come: the former serving specific users who pursue a seamless screen, and the latter continuing to meet the daily needs of the vast majority of consumers. As for when true full-screen displays will become truly universal, we will probably have to wait a while longer.