The kind of panel utilized by the display tells a lot about how the monitor will behave and function. The most popular display panel types are TN, IPS, and VA.
The liquid crystal layer is sandwiched between a backlight and polarising filters in an LCD. This liquid crystal layer controls the backlight’s strength and hue, whether red, green, or blue. A voltage is supplied to the liquid crystals to regulate their intensity. The arrangement of these crystals and their movement when voltage is applied distinguishes TN, IPS, and VA.
In the last three years, we’ve witnessed the debut of quicker IPS displays and significant improvements to VA panels, especially from Samsung Odyssey gaming monitors. Since then, we’ve evaluated over 100 monitors and have a lot more to say about performance.
So, let’s start with a quick overview before diving into the specifics of each technology.
TN stands for Twisted Nematic and is the earliest LCD technology. The twisted nematic effect enables voltage control of liquid crystal molecules. The TN-effect LCD uses a voltage to alter the alignment of liquid crystals. When the crystal is “off,” the liquid crystal molecules are twisted 90 degrees, allowing light to flow through. When a voltage is supplied, the crystals become untwisted and block light.
Vertical alignment (VA)
This technique utilizes vertically aligned liquid crystals that tilt when a voltage is applied. The crystals are perpendicular to the substrates in VA but parallel in IPS.
In-plane Switching (IPS)
In-plane Switching (IPS) utilizes voltage to align liquid crystals, much like other LCDs. IPS LCDs, unlike TN LCDs, have crystals parallel to the glass substrates, thus the name ‘in the plane.’ IPS crystals are rotated rather than ‘twisting’ to change the quantity of light allowed through.
These technologies come in a variety of sub-variants, and the brand names vary depending on the panel maker. For example, AU Optronics calls an IPS panel an “AHVA,” not a VA panel. Samsung uses PLS, whereas LG uses “IPS.” On the VA side, there’s AU Optronics’ “AMVA” and Samsung’s “SVA.”
In summary, TN panels twist, IPS panels rotate, and VA panels tilt. Now let’s look at some performance aspects and see how each technology differs and which technology is superior in each area.
The most noticeable difference between TN, IPS, and VA panels is the viewing angle. This is one area that hasn’t altered much since these technologies were introduced.
In both the horizontal and vertical orientations, TN panels have the worst viewing angles. Normal viewing angles are 170/160. However, you’ll have severe shifts if you don’t look dead center. While higher-end TNs tend to be better, this is a major flaw that may affect productivity when it comes to tasks like picture editing.
It is widely agreed that VA and IPS screens have superior viewing angles. Viewing angles are typically rated as 178/178, and although there may be some color and brightness shifts at off-center angles, this will be less apparent than on a TN panel. The bulk of the IPS panels we’ve tested have great viewing angles, which isn’t a problem with contemporary IPS displays.
VAs are excellent but not as good as IPS and may have more contrast shifting. However, many VA displays nowadays are curved, and any insertion of a curve decreases viewing angles. Remember it while choosing between IPS and VA.
Color & Contrast
No technical reason why TN, IPS, and VA displays should be brighter than any other. The average SDR brightness for IPS panels was 385 nits, compared to 367 nits for TN and 346 nits for VA across our current test suite’s 100 screens.
The contrast ratio, on the other hand, is a significant difference. The twisting method used in TN panels does not provide deep blacks. In the best instances, contrast ratios are about 1000:1, although, after calibration, they are usually in the 700:1 to 900:1 range. The typical TN has a contrast ratio of 872:1, which is low, so if you want deep, gorgeous blacks, acquire an OLED, but if you want LCD, avoid TNs.
IPS is the next step up, but IPS contrast ratios are similar to TN. In the worst instances – particularly LG’s current Nano IPS panels – contrast performance will be similar to a TN, with a ratio below 1000:1. It’s far more usual to observe contrast at or over 1000:1, with some best-case instances going up to 1500:1, which I’ve seen with IPS. Our IPS panels had an average contrast ratio of 1037:1, which is 19% greater than a TN.
To get deep blacks from an LCD, you’ll need a VA panel. The architecture of these panels allows for greater contrast ratios, usually starting at 2000:1 than even the finest IPS panels.
Anti-glare, matte coatings on almost all monitors decrease the effective contrast ratio in brighter settings. The contrast ratio difference between TN, IPS, and VA will be less apparent if you use your monitor during the day or under artificial light. If you frequently use your monitor in a dark setting, like gaming with the lights off or browsing incognito late at night, you’ll notice the huge advantage VAs offer in this area.
While IPS panels are a good compromise for contrast, they suffer from a phenomenon known as “IPS glow,” which is an apparent white glow when viewing black images from an angle. The finest panels have little glow, although it affects all screens of this kind and varies across units.
We’ve already discussed the distinctions between TN, IPS, and VA panels in terms of bit depth — or the difference between 6-bit, 8-bit, and 10-bit panels. But we think this is less important now that most displays are native 8-bit, with the exception of a few low-end 6-bit and professional-grade high-end 10-bit panels.
Most displays marketed as “10-bit” or “1 billion colors” are not genuine 10-bit panels but rather use FRC or dithering, and the LCD panel technology used makes no difference.
The coverage of “standard” color spaces like sRGB or Rec. 709, which is used by default in Windows and extensively utilized for video content, is also similar across LCD kinds these days.
Even TN panels, which traditionally had the “worst” color fidelity, now cover over 95% of the sRGB color gamut. However, it’s uncommon for a desktop monitor to go below 90% sRGB coverage, and you shouldn’t purchase it if it does.
Native 10-bit requires an IPS panel, which is the majority of native 10-bit screens. Only a few VA panels can accomplish that. Most 10-bit displays are really 8-bit+FRC, with few high-end professional monitors providing a true 10-bit experience.
Because there has been a great deal of emphasis on developing TN, IPS, and VA panels in recent years, it is considerably more difficult now than it was in past years to summarise each of the three major LCD technologies. This has resulted in much-improved gaming monitors for everyone, as well as a plethora of additional displays to examine and keep us occupied, which is always a good thing.