Ever since the invention of the LCD screen back in 1996, constant innovation in the sector has lead to bigger and better versions over the years.
LCDs come in various architectures. They are classified as TFT (Thin Film Transistor), TN (Twisted Nematic) and VA(Vertical Alignment).VA is further divided into MVA (multi-domain vertical alignment), PVA (patterned vertical alignment) and ASV (advanced super view).
TN displays are used in a variety of applications such as Mobile Phones, Computer Monitors, Handheld Gaming Devices and PDAs. Twisted Nematic Displays work by twisting the liquid crystal molecules in the panel 90 degrees between polarizers and are placed vertically to the panel plane.A downside to this is that the molecules in the Liquid Crystals alter the further away they are from the electrodes. This causes diminishing contrast, brightness and colour definition at wider viewing angles and provides a poor viewing experience if viewed at an angle.
TN displays are not the best for photo editing due to a limited viewing angle and also the color and contrast change to a fair degree if the viewing angle is not dead center. A way around this problem is the introduction of Vertical Alignment (VA) displays.VA displays offer a wide viewing angle, There are several variations of the VA architecture such as such as MVA (multi-domain vertical alignment), PVA (patterned vertical alignment) and ASV (advanced super view). But the VAs suffer from poor image quality at the cost of a wide viewing angle.
Another issue that plagued earlier productions was ghosting or trailing in fast moving pictures; these were an eyesore and resulted in blurry pictures and watery eyes for the viewer. The problem is now fixed by faster response times, which remove any trace of ghosting and provide a blur-free viewing experience. Nowadays, response times are advertised as G2G (Grey To Grey) as the previous emphasized response times did not reflect the performance across the entire range of possible colour changes. Today 4ms and 2ms are commonplace for TN-based displays.
Once IPS (In Plane Switching) technology was invented, a lot of the problems associated with poor viewing angles and colour reproduction were resolved to a great extent.
The way it works, is that unlike TN displays where crystal molecules move perpendicular to the panel, the crystals used in IPS displays move parallel to the panel plane. An IPS display offers a wide viewing angle and accurate colour reproduction.
IPS technology innovatively aligns liquid crystal horizontally to increase the viewing angle and changes the LCD transmittance. This provides true wide viewing angles and the colours are consistent and accurate when viewed even from an angle. The images produced are closest to the actual colour, and IPS displays place very little stress on the eyes which greatly enhances your viewing experience. IPS based LCD monitors also feature high bit-depth and an ultra wide colour gamut, which is defined as equal or greater than the Adobe RGB (1998) color space. This technology nullifies any ghosting or trailing.
One interesting variation of the IPS technology is the AH-IPS architecture.. This type of IPS panel uses AFFS (advanced fringe field switching) technology. This architecture performs really well for smaller screens with high resolutions, great for devices such as the Apple iPad.
AH-IPS also has the advantage of greater light transmission, which in turn translates into lower power consumption. So far, this technology has been limited to small screens due to higher manufacturing costs for larger screens.
Published Date: Nov 01, 2010 12:47 pm | Updated Date: Nov 01, 2010 12:47 pm