There are different monitor technologies that each affect picture quality in their unique way. Each panel technology has its strengths and weaknesses, and choosing the best one for you usually depends on your usage and personal preferences.
In this article, we'll look at the main differences between three of the most common panel types used today: IPS, VA, and TN. We'll break down different aspects of picture quality and motion handling to ensure you have the information necessary to make an informed purchasing decision.
Almost all monitors use LCD (Liquid Crystal Display) panels lit by LED backlights. There are three main types of LCD panels: In-Plane Switching (IPS), Vertical Alignment (VA), and Twisted Nematic (TN). The general idea of each panel type is the same: liquid crystals react to an electric charge, controlling how much light is allowed to pass through and reach each of the three colored sub-pixels.
For this article, we'll take a look at three recent high-performance gaming monitors: the LG 27GP950-B, the Samsung Odyssey G7 LC32G75T, and the ASUS TUF Gaming VG258QM. We'll compare a few aspects of their performance, including picture quality and motion handling.
IPS, which stands for in-plane-switching, uses a different crystal orientation compared to VA and TN. While TN and VA twist the crystals, IPS crystals are parallel with the glass substrate, and they rotate within the plane of the substrate to let light through, similar to the shutter on a camera. IPS panels are by far the most common on today's monitors.
VA, or vertical alignment, uses vertically aligned crystals that tilt to allow light to pass. While IPS crystals are parallel with the glass substrate, VA crystals are perpendicular to the substrate. Although VA panels aren't as common as IPS panels for monitors, they're one of the most common choices for TVs.
TN, or twisted nematic, was the first LCD technology on the market. TN panels consist of liquid crystals sandwiched between two polarizing filters. When an electric current is applied, the crystals twist and allow light to pass through. TN panels are by far the cheapest, but they're also a bit out of date and not as common.
It can be hard to generalize how each LCD type performs. In most cases, the difference between each type is pretty minor, but there are a few key areas where one type is consistently better than the others. We won't be talking much about extra features or design elements, as these vary depending on the overall market context of the monitors you're looking at. There are high-end and low-end models of each, and the feature sets and performance vary accordingly.
Although most monitors today look pretty good, there are some noticeable differences, depending on the type of LCD used. The most significant differences between the different LCD panels are in their contrast ratios and viewing angles, but there can be some subtle differences in other aspects of the overall picture quality.
VA panels have the clear advantage here. TN panels have the worst contrast by far, typically in the 600:1 - 1200:1 range. IPS panels are slightly better, ranging between 700:1 - 1500:1, but they're still not as good as VA panels. Most VA panels on monitors have contrast ratios above 2500:1, with some as high as 5000:1 - 6000:1. Newer monitors even use local dimming to achieve much higher contrast ratios. Even with local dimming, IPS monitors aren't able to produce blacks as deep as VA panels. In short, if you're often using your computer in a dark room, a VA panel is the way to go, as it's the only LCD panel type that can produce deep blacks in a dark room. If you're not in a dark room, the difference in contrast is hardly noticeable, especially since many monitors have anti-glare coatings that can reduce the effective contrast ratio of the display.
Of the three monitors shown here, the Samsung has the best contrast, at nearly 4x the contrast ratio of the other two. We measure contrast at a fixed white level of 100 cd/m², so this means the Samsung's blacks are, on average, 4x darker than the others. The other two are about what we expect from TN and IPS displays, but the ASUS is at the upper end of the range for TNs. Most TN monitors we've tested are much worse than this one.
Since the brightness is controlled by a backlight behind the LCD layer, the type of LCD used has essentially no impact on the peak brightness of the display. That said, there's a difference between TN and VA/IPS, but it has more to do with market limitations than technological ones. TN monitors aren't nearly as popular as they used to be, and the remaining models tend to target high-performance gaming, so there's less of a focus on brightness. Because of this, almost all high-end monitors currently on the market use VA or IPS panels, so if you're looking for a very bright image, especially for HDR, chances are it'll be either VA or IPS.
Winner: IPS and VA
IPS is the clear winner here, as the image remains accurate even at a wide angle. VA and TN monitors usually perform much worse. Color accuracy generally remains good on VA monitors, but TNs have a slight shift in color accuracy at moderate angles. They both usually show a decrease in brightness at moderate angles and gamma shift at a small angle, causing the image to appear washed out. Panel manufacturers came out with curved panels to compensate for this image degradation, as the curved screen reduces the viewing angle to the edge of the screen, meaning that the image appears more uniform if you're sitting up close. Most curved monitors are VA, but there are a handful of TN panels as well. Unfortunately, we measure the viewing angles from the center of the screen and rotate the monitor while still measuring in the center, so any advantages from the curve aren't apparent in our test results.
Some manufacturers have started adding wide-angle filters to VA panels used in TVs. These filters significantly improve viewing angles, but come at the expense of contrast. We haven't seen any VA monitors with this technology yet, but we wouldn't be surprised if manufacturers started adding wide-angle filters to some high-end monitors.
Again, IPS is the clear winner here. The vertical viewing angles are very similar to the horizontal ones on both IPS and VA panels. Unfortunately, this is one area where TN panels are usually much, much worse. TN monitors degrade rapidly from below, and colors actually inverse - resulting in a negative image that can be distracting. For this reason, if you decide to buy a TN monitor, look for one with an excellent height adjustment, or consider buying a VESA mounting arm, as you should mount TN monitors at eye level. Even when mounted properly, larger TN displays can appear non-uniform at the edges.
There's usually not much difference between VA and IPS panels in terms of gray uniformity. It's rare for monitors to have uniformity issues, and even on monitors that perform worse than average, it's usually not noticeable with regular content. TN monitors tend to perform a bit worse than usual, though, and the top half of the screen is almost always darker than the rest, but that's an artifact of the bad vertical viewing angles.
Winner: VA and IPS
Black uniformity tends to vary significantly, even between individual units of the same model, and there's no single panel type that performs the best. It's rare for monitors to have good black uniformity, and almost every monitor we've tested has some noticeable cloudiness or backlight bleed. IPS and TN panels can look slightly worse due to their low contrast ratios, as the screen can take on more of a bluish tint when displaying dark scenes. Like with contrast, black uniformity issues usually aren't very noticeable unless you're looking at dark content and you're in a dark room. If you only use your monitor in a bright environment, generally speaking, you don't need to worry about black uniformity.
Winner: VA, but not by much.
Historically, TN panels used to have the worst colors, as many of them were cheaper models that only supported 6-bit colors or used techniques like dithering (FRC) to approximate 8-bit colors. Most displays today, including TN models, are at least 8 bit, and many of them are even able to approximate 10-bit colors through dithering. New technologies, like LG's Nano IPS and Samsung's Quantum Dot, add an extra layer to the LCD stack and have significantly improved the color gamut of modern IPS and VA displays, leaving TN a bit behind. Between them, NANO IPS is slightly better, as it tends to offer better coverage of the Adobe RGB color space. Although the difference is minor, IPS panels still have a slight edge over VA and TN displays.
Although TN panels have caught up a bit in the SDR color space, they're far behind when it comes to HDR, so if you're looking for a good HDR color gamut, avoid TN panels. Between VA and IPS panels, the difference isn't as significant; however, IPS panels still have a slight edge. The best VA panels top out at around 90% coverage of the DCI P3 color space used by most current HDR content. IPS panels go as high as 98% coverage of DCI P3, rivaling even some of the best TVs on the market. Due to the very high coverage of DCI P3 on both VA and IPS, the difference isn't that noticeable, though, as most content won't use the entire color space anyway.
Although not necessarily as noticeable to everyone as the differences in picture quality, there can also be a difference in motion handling between IPS, VA, and TN displays. TN panels historically offered the best gaming performance, as they had the highest refresh rates and extremely fast response times. Manufacturers have found ways to drastically improve the motion handling of VA and IPS panels, though, and the difference isn't as pronounced.
Winner: TN & IPS
LCD panel technology has changed drastically over the last few years, and the historical expectations for response time performance don't necessarily hold anymore. For years, TN monitors had the fastest response times by far, but that's started to change. New high refresh-rate IPS monitors can be just as fast.
VA panels are a bit of a strange situation. They typically have slightly slower response times overall compared to similar TN or IPS models. It's especially noticeable in near-black scenes, where they tend to be significantly slower, resulting in dark trails behind fast-moving objects in dark scenes, commonly known as black smear. Some recent VA panels, such as the Samsung Odyssey G7 LC32G75T, get around it by overdriving the pixels. It results in much better dark scene performance but a more noticeable overshoot in brighter areas.
The examples listed above aren't perfect. The average response time metrics shown don't necessarily show the whole picture. Monitors also usually offer a certain level of control over the pixel overdrive, so it's possible to adjust the response time to match your usage and personal preference. Some overdrive settings deliver a sharper image but introduce overshoot and reverse ghosting artifacts, while other modes might not be as sharp but have no distracting artifacts. You can learn more about our response time testing here.
Within each of the three types of LCD we mentioned, other related panel types use the same basic idea but with slight differences. For example, two popular variants of IPS panels include ADS (technically known as ADSDS, or Advanced Super Dimension Switch) and PLS (Plane to Line Switching). It can be hard to tell these panels apart simply based on the subpixel structure, so we'll usually group them all as IPS, and in the text, we'll usually refer to them as IPS-like or IPS family. There are slight differences in colors, viewing angles, and contrast, but generally speaking, they're all very similar.
There's another display technology that's growing in popularity: OLED. OLED, or organic light-emitting diode, is very different from the conventional LCD technology we've explored above. OLED panels are electro-emissive, which means each pixel emits its own light when it receives an electric signal, eliminating the need for a backlight. Since OLED panels can turn off individual pixels, they have deep, inky blacks with no blooming around bright objects. They also have excellent wide viewing angles, a near-instantaneous response time, and excellent gray uniformity.
OLED panels aren't perfect, though. There's a risk of permanent burn-in, especially when there are lots of static elements on screen, like the UI elements of a PC. There aren't many OLED monitors available, either, but they've started to gain popularity as laptop screens and for high-end monitors, but they're very expensive and hard to find. They're also not very bright in some cases, especially when large bright areas are visible on screen. The technology is still maturing, and advances in OLED technology, like Samsung's highly-anticipated QD-OLED technology, are promising.
As you can probably tell by now, no one panel type works best for everyone; it all depends on your exact usage. Although there used to be some significant differences between panel types, as technology has improved, these differences aren't as noticeable. The two exceptions to this are viewing angles and contrast. If you're in a dark room, a VA panel that can display deep blacks is probably the best choice. If you're not in a dark room, you should focus on the other features of the monitor and choose based on the features that appeal to your exact usage. IPS panels are generally preferred for office use, and TN typically offers the best gaming experience, but recent advancements in VA and IPS technology are starting to change those generalizations. For the most part, the differences between each panel type are so minor now that it doesn't need to be directly factored into your buying decision.