Are LG’s OLED screens terrible, or are they the best in the business? Reading tech reviews, you’ll see both of those statements. That’s because you’ll get two wildly different stories about OLED depending on whether you’re reading a TV or phone review.

Phone critics say LG OLED panels have quality issues. Meanwhile, TV critics say the opposite—that LG’s OLED panels are marvelous. It’s confusing for the consumer, so let’s clarify right now. The critics aren’t contradicting each other, because LG makes industry-leading, amazing OLED TV panels, and, at the same time, the same company makes highly problematic OLED phone panels. That’s not to say that LG’s OLED TVs are perfect—every technology has tradeoffs, like very minor color banding in this case. But at a minimum, they’re up there with the best consumer TVs the market has yet seen.

So why did the Pixel 2 XL and LG V30 have bad phone displays, when LG clearly can make a good OLED screen for TVs? And why do the Galaxy S8+ and iPhone X have better OLED screens than the Pixel 2 or the LG V30, but still not as good as LG’s TVs?

What is OLED?

OLED stands for “organic light-emitting diodes,” and it’s very different from the popular LCD screen technology seen in most phones and TVs in recent years. For a robust description of the tech, read our previous explainer article about OLED. But here’s what matters to most users and viewers: unlike LCD panels used in most phone and TVs, OLED panels don’t have a backlight. Each pixel is individually lit.

Because each pixel can be controlled individually, OLED TVs can display true, actual blacks—something LCD displays simply aren’t capable of and never will be. This could have implications for battery life in the long run, but, in the meantime, it definitely leads to better picture quality thanks to increased contrast ratios. Response times are often quite good, as well—as are viewing angles, in some implementations.

OLED TVs entered the market at very high price points. This was because certain materials used to make them, like iridium, are comparatively expensive. And many of those materials are wasted in the manufacturing process; manufacturers would produce the equivalent of several television panels but would have to discard the majority of those materials in pursuit of just one panel. This gap has closed over time, bringing down prices.

There have been experiments from various manufacturers with OLED phone screens in recent years, but with the Pixel 2 XL, the iPhone X, the Samsung Galaxy S8, and more, this seems to be OLED’s mobile moment at long last.

POLED vs. AMOLED vs. OLED

LG calls its phone OLED displays POLED and its TVs OLED, while Samsung calls its phone displays AMOLED. It turns out that, at least between POLED and AMOLED, there’s little difference; it’s mostly marketing speak.

There are two types of OLED displays—passive- and active-matrix. The “AM” in AMOLED stands for active-matrix. Passive-matrix OLED panels are cheaper and easier to make, but quality moving images all but require the use of active matrix OLED panels. So for the purpose of smartphone comparisons, Samsung’s nomenclature is pointless—virtually all modern OLED smartphones or TVs are active-matrix. You could really just say OLED.

LG’s POLED is also irrelevant as terminology goes. OLED displays can be made with a variety of different substrate materials. They can be plastic, or they can be glass. Glass substrates are generally better for image quality, but plastic is cheaper, more durable, and more easily bendable into unusual shapes—think about those curved edges on Samsung’s Galaxy S8+ display. On modern smartphones, both LG and Samsung use plastic substrates. So the P for “plastic” is also useless for comparison. They’re all plastic, at least where phones are concerned.

That doesn’t mean there aren’t differences between Samsung’s panels and LG’s, though. We’d love to specifically diagnose why LG’s panels are worse than Samsung’s, but there are many possible culprits in both known and unknown differences. That said, neither company shares all the details of its manufacturing process publicly.

But Samsung’s panels—as used in the Samsung Galaxy S8+ and the iPhone X—have been better received than LG’s. Just look at these comparisons captured and written by Ars’ own Ron Amadeo in his Google Pixel 2 and Pixel 2 XL review, plus his comparison between an LG OLED-equipped LG V30 and both an LCD-equipped LG G6 and a Samsung OLED-equipped Galaxy S8:

When I reviewed the iPhone X, which uses a Samsung-made OLED panel, I found it had much more in common with the Galaxy S8 where the screen was concerned, and DisplayMate’s analysis called it the best smartphone display out there. It had some noticeable color shifting at an angle, and burn-in may be a risk. But blotchiness, low-light performance, and color inaccuracy were not significant concerns.

But in any case, none of these displays hold a candle to LG’s OLED TVs.

TVs and phones

LG’s OLED TVs have few of the problems endemic in phone displays. Yes, there’s color banding. But an LG C7 or B7 consumer OLED TV’s image appears nearly the same whether viewed from a hard angle or directly from the front. Burn-in is a concern, but it takes many hours of a certain image’s persistent presence—like say, the always-visible UI elements in a video game over dozens or more likely hundreds of hours of play—to create an issue. In most cases, the screen returns to normal and clears up fairly quickly after viewing other content. And compare the gray uniformity image in Rtings.com’s LG B7 OLED TV review to the images from OLED smartphones above. It’s not even close.

The approaches, materials, and technologies at play in these TVs are sometimes different in fundamental ways compared to phones. For example, many (but not all) phone OLED displays have used what’s called a “diamond pixel arrangement,” which is markedly different from the WRGB arrangement used in LG’s OLED TVs.

In LG’s OLED TVs, each pixel is a white OLED point of light made out of three colored layers, but color filters actually create the red, green, and blue subpixels. It might seem like an odd approach, but it has advantages in longevity, viewing angles, and cost.

But even though the OLED TVs make compromises, OLED phones make bigger ones. There is no beating around the bush: the diamond pixel arrangement used in Samsung’s phones, in the iPhone X, and in many other OLED phones sacrifices accuracy and quality.

So many factors are at play, though, that we can’t just blame the differences on that. Phone manufacturers have to worry about power consumption more. LG TV panels are made using different materials and production processes than LG phone panels. And there are likely numerous differences that are not publicly known.

Samsung has been working for several years to mature its phone OLED panel technologies. LG has been working for years doing the same on TVs. LG’s display division reportedly wanted to focus on larger panels for a long time, so the company is now playing catch-up on mobile. But regardless of the manufacturer, not all OLED panels are created equal; that picture gets even clearer when comparing phones and TVs. The technology may have been around for years now, but it’s still only just maturing—especially when it comes to mobile.

So don’t write off OLED TVs just because the Pixel 2 XL and LG V30 have poor OLED screens. And expect OLED to keep getting better in all types of products.