Twisted nematic or TN panel, vertically aligned or VA panel, and in-plane switching or IPS panel are three broad types of thin-film-transistor liquid crystal display or TFT LCD that have become very popular screen display technologies used in an array of consumer electronic devices.
Among these three variants, IPS is a more recent LCD technology. Furthermore, the advantages of an IPS panel over a TN panel or a VA panel have made it a more popular LCD option used in modern consumer electronic devices such as smartphones and tablet computers.
Depending on the functional scope of a particular device however, a TN panel or a VA panel can have more advantage over an IPS display. This article compares and contrasts these three LCD technologies using six common display characteristics: color reproduction, viewing angle, contrast ratio, pixel response time, power consumption, and cost and price.
TN panel vs. VA panel vs. IPS panel: Which one is better?
1. Color reproduction: Poor color reproduction is one of the disadvantages of twisted nematic LCD. Therefore, one of the advantages of a VA panel and an IPS panel over a TN panel is color accuracy and better image quality due to better color reproduction.
Most VA and IPS panels have an 8-bit RGB color depth compared with the 6-bit RGB color depth of TN panels. Among the three however, IPS panel has the better color reproduction. Several IPS panel variants have featured 16-bit to 24-bit RGB color depth.
Note that a 6-bit display panel means that the red, green, and blue channels of its single pixel are capable of 64 levels, thus producing 262,144 possible colors. Meanwhile, an 8-bit display has 256 levels in each single pixel, thus producing 16.7 million possible colors.
The color reproduction advantage of VA panel has made it a popular LCD technology used in high-end computer monitors and large HD television sets. But IPS panels are becoming more popular in smartphones and tablet computers. Because of its superior color reproduction, IPS is also a favorable LCD option for color critical works such as graphic design and video editing.
2. Viewing angle: Strong dependence on viewing angle is another disadvantage of twisted nematic LCD. A user needs to view a TN panel from a straight up 90-degree angle to maximize its visual performance. When viewed from other angles, colors and images on a TN panel will appear duller and darker.
However, a close comparison between a VA panel and a TN panel will reveal that the former has a better viewing angle. But most VA variants suffer from color shifting. This means that uneven brightness levels across a VA screen become noticeable when viewed from a slightly different angle.
Wide viewing angle is an advantage of an IPS panel over TN and VA panels nonetheless. High quality IPS panels produce consistent brightness and contrast levels when viewed from different angles. This is the reason why in-plane switching has become an ideal LCD technology for entertainment devices such as television sets and mid-range to high-end smartphones and tablet computers.
A narrow viewing angle provides some privacy and security however. This can be an advantage of TN panel over an IPS panel. This means that a TN panel can be an ideal LCD option for individuals or organizations that handle sensitive information in the presence of other people.
3. Contrast ratio: Contrast ratio is the ratio between the luminance of the brightest color and that of the darkest color. In other words, it is the difference between the brightest whites and the darkest blacks.
Low contrast ratio is another disadvantage of twisted nematic LCD technology when compared against vertical alignment and in-plane switching LCD technologies. However, between a VA panel and an IPS panel, the former has a better contrast ratio.
Backlighting can be blocked effectively in a vertical alignment LCD technology, thus producing deeper blacks and a higher contrast ratio compared to in-plane switching LCD technology.
Higher contrast ratio naturally corresponds to better display panel quality and manufacturers have banked on this to promote the superiority of their product over their competitors. Still, some argues that contrast ratios are all hype because of the absence of testing standards in the industry.
4. Pixel response time: Pixel response time refers to the duration it takes a single pixel to transition from one state to another. Measured in milliseconds, the lower the number, the better. Long pixel response time creates ghosting effect or motion blur around a moving object, thus producing an unsuitable viewing experience for rapidly moving images.
A shorter and better pixel response time is a very notable advantage of TN panel over a VA panel and an IPS panel. Both vertical alignment and in-plane switching LCD technologies inherently suffer from longer pixel response time. However, a comparison between a typical VA panel and a typical IPS panel will reveal that the former has the worse pixel response time.
The response time advantage of TN panel makes it a perfect LCD option for fast-paced gaming and hardcore gamers. Although there are VA and IPS variants that feature reduced pixel response times, these panels are more expensive than TN panels.
5. Power consumption: Low power consumption is another advantage of twisted nematic LCD technology over vertical alignment and in-plane switching LCD technologies.
TN technology does not require a current to flow during operation. It also uses low operating voltages. These advantages make TN panels popular in low-powered LCDs found in portable and miniscule electronic devices such as digital watches and calculators.
Note that VA panels and IPS panels are largely popular in power-intensive devices such as computer monitors, smartphones and tablet computers, and television sets.
6. Cost and price: Among the three LCD technologies, twisted nematic LCD technology is easier to implement. This means that twisted nematic panels are inexpensive to manufacture, thereby resulting in low prices for end users.
VA panels are more expensive than TN panels. However, they are relatively inexpensive when compared against IPS panels. This is the reason why VA computer monitors and television sets were very popular before the advent of IPS panels.
Because IPS panels are more expensive among the three LCD technologies, they are usually found in mid-range to high-end consumer electronic products. But the growing popularity of in-plane switching LCD technology is currently driving down the prices of IPS panels. Some IPS units are actually considerably cheaper than high-end VA panels.
Conclusion: TN panel vs. VA panel vs. IPS panel
The aforementioned comparison among TN panel, VA panel, and IPS panel revealed that there is no LCD type that is better at everything. Each type of LCD technologies has its own advantages and disadvantages.
From the list above, TN panels have remained an ideal LCD option used in minuscule electronic devices such as digital watch and calculator because they are very cheap to manufacture and consumes less power. They also remain a popular computer monitor option because of their affordability and fast response time.
On the other hand, IPS panels have the best color reproduction, color accuracy, and wider viewing angle compared with TN and VA panels. These panels have been featured in mid-range and high-end consumer electronic devices such as laptops, smartphones, and tablet computers. IPS is also an ideal computer output display for color critical tasks.
VA panels are situated between TN panels and IPS panels. They are more expensive than TN but are relatively cheaper than IPS panels. They offer better color reproduction and more decent viewing angle than TN panels although these characteristics are not superior over IPS panels.